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Neuroendocrine tumors (NET) of the thymus are rare, usually aggressive, and prone to metastatic lesion. Ectopic adrenocorticotropic hormone (ACTH) secretion in thymic NET (TNEN) is associated with poor prognosis. Most of TNET express somatostatin receptors, it allows the use of somatostatin receptor scintigraphy (SRS) and SPECT/CT or PET/CT with 68Ga-labeled peptides for diagnosis and staging of the disease. Surgery (macroscopic-complete resection) is the mainstay treatment for TNET. Now, there are no unequivocal data in adjuvant therapy and its effectiveness. We present a case report of the pediatric patient with well differentiated atypical ACTH-producing thymic carcinoid. This localization was verified by whole body somatostatin receptor scintigraphy with 111In-DTPA-octreotide (Octreoscan). The patient proceeded with the surgical treatment followed by remission of hypercorticism without adjuvant chemotherapy. Tumor recurrence with redevelopment of ACTH-ectopic syndrome was detected after 67 months of observation.

Abstract Background This study investigated the frequency of diabetic gastroparesis and associated risk factors in a real-world clinical setting. Methods This retrospective cross-sectional study included patients who underwent assessments of solid gastric emptying time (GET) by technetium-99 m scintigraphy between May 2019 and December 2020. We categorized patients into three groups according to gastric retention of technetium-99 m: rapid ( 60% at 2 h and/or > 10% at 4 h). Results Patients with diabetes mellitus (DM) were more likely to show abnormal GET than those without DM (119 [70.8%] vs. 16 [44.4%]). The mean glycated A1c was 10.3% in DM patients. DM patients with normal GET were significantly younger (57.2 years, P = 0.044) than those with delayed (65.0 years) or rapid GET (60.2 years). Fasting glucose levels were the lowest in the normal GET group and the highest in the rapid GET group (delayed: 176.3 mg/dL, normal: 151.2 mg/dL, rapid: 181.0 mg/dL, P = 0.030). However, glycated A1c was not significantly different among the delayed, normal, and rapid GET groups in patients with DM. Patients with delayed and rapid GET showed a higher frequency of retinopathy (6.0 vs. 15.5%, P = 0.001) and peripheral neuropathy (11.3 vs. 24.4%, P = 0.001) than those with normal GET. In the multinomial logistic regression analysis, retinopathy demonstrated a positive association with delayed GET, while nephropathy showed a significant negative correlation. Conclusion DM gastroparesis in the clinical setting was not uncommon. Abnormal GET, including delayed and rapid GET, was associated with DM retinopathy or peripheral neuropathy.

Key Clinical Message We report a patient with nonimmune fetal hydrops and multiple pathologic fractures. RNA analysis revealed a novel PIEZO1 variant. This report is the first to elucidate PIEZO1's role as a critical regulator of bone mass and strength.

Multimodality reporter gene imaging combines the sensitivity, resolution and translational potential of two or more signals. The approach has not been widely adopted by the animal imaging community, mainly because its utility in this area is unproven. We developed a new complementation-based reporter gene system where the large component of split NanoLuc luciferase (LgBiT) presented on the surface of cells (TM-LgBiT) interacts with a radiotracer consisting of the high-affinity complementary HiBiT peptide labeled with a radionuclide. Radiotracer uptake could be imaged in mice using SPECT/CT and bioluminescence within two hours of implanting reporter-gene-expressing cells. Imaging data were validated by ex vivo biodistribution studies. Following the demonstration of complementation between the TM-LgBiT protein and HiBiT radiotracer, we validated the use of the technology in the highly specific in vivo multimodal imaging of cells. These findings highlight the potential of this new approach to facilitate the advancement of cell and gene therapies from bench to clinic.

Sarcoidosis is a systemic granulomatous disease; however, the incidence of bone sarcoidosis is relatively rare. The short tubular bones of the hands and feet are most frequently affected, while the vertebrae and the pelvic bones are rarely involved. We hereby report a rare case of multiple bone sarcoidosis involving the vertebrae and pelvic bones, evaluated before and after steroid therapy using two different imaging modalities: bone scintigraphy and A 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT). FDG-PET/CT is effective for detecting bone lesions; however, whole-body imaging is recommended to detect the short tubular bones of the hands and feet, which are most frequently affected.

The iodine-131 (I-131) content in the thyroid of staff members working with this radionuclides has been measured with about 500 employees in about 25 hospital’s departments of nuclear medicine performing therapy and diagnosis of thyroid disease in Poland. The measurements were performed with portable detection unit for in situ measurements of radioiodine. This is consist with scintillation detector sodium iodine activated by thallium (NaI(Tl)) – battery-powered and portable tube base Multichannel Analyzer Canberra UniSPEC. Based on direct measurements of the iodine content, the effective dose equivalent for workers due to inhalation of I-131 was estimated. All individuals actively working with iodine show measurable amounts of this isotopes in their thyroids. The average measured activity in the thyroid of the nuclear medicine staff was found to be equal at average 550 Bq within the range 70 Bq–2.5 kBq. There is no apparent correlation between the measured I-131 levels and risk categories. Nevertheless the technical and nuclear medicine staff show higher I-131 thyroid level comparing to hospital services staff. Calculated maximum committed effective dose for particular exposed person is

Breast cancer is one of the most prevalent cancers worldwide, and early diagnosis and screening are vital to its successful treatment. Although medical imaging methods can assist in the early detection of breast cancer, imaging methods that are currently used for clinical diagnosis have drawbacks, such as low sensitivity and accuracy. Contrast agents are often used in diagnostic imaging to address these drawbacks. Nanocontrast agents have attracted considerable attention in recent years due to their unique physicochemical characteristics. Among these agents, inorganic nanoprobes have been substantially developed through improvements in synthesis techniques and pairings with other organic molecules. This paper mainly summarizes the specific applications of inorganic nanoprobes in the magnetic resonance imaging, fluorescence imaging, radionuclide imaging, and bimodal/multimodal imaging of breast cancer.

Gastrointestinal (GI) bleeding is not a single disease but a symptom and clinical manifestation of a broad spectrum of conditions in the GI tract. According to its clinical presentation, GI bleeding can be classified into overt, occult, and obscure types. Additionally, it can be divided into upper and lower GI bleeding based on the Treitz ligament. Variable disease entities, including vascular lesions, polyps, neoplasms, inflammation such as Crohn’s disease, and heterotopic pancreatic or gastric tissue, can cause GI bleeding. CT and conventional angiographies and nuclear scintigraphy are all radiologic imaging modalities that can be used to evaluate overt bleeding. For the work-up of occult GI bleeding, CT enterography (CTE) can be the first imaging modality. For CTE, an adequate bowel distention is critical for obtaining acceptable diagnostic performance as well as minimizing false positives and negatives. Meckel’s scintigraphy can be complementarily useful in cases where the diagnosis of CTE is suboptimal. For the evaluation of obscured GI bleeding, various imaging modalities can be used based on clinical status and providers’ preferences.

A planar nuclear medicine image can be used to estimate dosimetry during iodine therapy. To this end, radionuclide activity distribution should be quantified in the patient’s body in terms of a calibration coefficient. This coefficient allows the net counts to correlate with the image’s activity. This study aims propose a simple and easy calibration protocol to quantify 131I activity in thyroid phantom by molecular planar images. Were acquired 13 planar images of different phantoms: thyroid phantom of symmetrical lobes; thyroid phantom of asymmetrical lobes; the Jacszack cylinder phantom with a syringe surrounded by air and water, and finally a plastic bottle containing a syringe with radionuclide. We applied the 131I radionuclide in a General Electric gamma camera, model Discovery NM/CT 670 with a high energy general purpose parallel hole collimator above the phantoms positioned at camera bed. The calibration coefficient of the gamma camera and the standard deviation were determined for each phantom; the average calibration coefficient obtained was 0.062±0.006 MBq/cps. The results suggested that the phantoms applied as too the calibration coefficient obtained by them can provides reasonable value for the gamma camera calibration factor for iodine 131, therefore an accurate evaluation of the scattering media as the source detector distance could impose higher variability and uncertainties on results.

AbstractPurpose Thyroid nodules are a kind of common endocrine system disease, with approximately 5% of them developing into malignant lesions, the most common of which belong to differentiated thyroid carcinoma (DTC). Accurate differential diagnosis using reliable methods and targeted treatment of benign and malignant thyroid nodules are of great significance to improve patient outcomes. This study mainly investigates the diagnostic value of thyroglobulin (Tg) and anti-thyroglobulin antibody (anti-TgAb) combined with emission computed tomography (ECT) in the adjuvant diagnosis DTC.Methods All the data of 387 histopathologically diagnosed DTC patients (observation group) and 151 patients with nodular goiter (control group) admitted between June 2019 and June 2021 were collected and retrospectively analyzed. Serum Tg and anti-TgAb levels were detected in all subjects. In addition, all patients in the observation group underwent thyroid ECT, and the results were compared with the pathological findings. The receiver operating characteristic (ROC) curve was drawn to analyze the diagnostic performance of Tg, TgAb and thyroid ECT, either alone or in combination, in patients with thyroid cancer (TC).Results The consistency test showed that Tg (Kappa-value = 0.370) and anti-TgAb (Kappa-value = 0.393) had generally consistent efficiency with pathological findings in the diagnosis of DTC; ECT (Kappa-value = 0.625) and the combined diagnosis of the three (Kappa-value = 0.757) showed higher consistency than the pathological diagnosis, of which the combined diagnosis contributed to an even higher consistency. The combined diagnosis of Tg, anti-TgAb, and thyroid ECT outperformed either of these alone in DTC diagnosis, with a sensitivity of 91.5%, a specificity of 86.1%, and an accuracy of 90%.Conclusions The combination of Tg. anti-TgAb, and RNI can effectively improve the diagnostic accuracy of DTC and reduce the missed diagnosis rate, which has important reference significance for clinical diagnosis and treatment of TC.

Objective(s): While increased uptake at the bone fractural site gradually decreases over time on bone scans, the rate of change has not been quantitatively evaluated. The purpose of this study was to quantify the extent of bone metabolic changes in fractural lesions on bone SPECT/CT. Methods: We reviewed bone scans acquired by dedicated SPECT/CT and chose those scans in which quantitative SPECT/CT of the same range was acquired twice or more. We set the region of interest on lesions of bone fracture and degeneration, and measured the maximum standardized uptake value (SUVmax). From the SUVmax of lesions and the interval between scans, a value for 30-day change in SUVmax was calculated as DSUVmax30d. The relationship between preSUVmax, SUVmax for the first scan of the comparison, and DSUVmax30d was evaluated utilizing a linear least-squares method. Furthermore, we assessed the ability to differentiate between fracture and degeneration using receiver operating characteristics (ROC) analysis and the Mann-Whitney U test. All cases were then categorized into five groups according to preSUVmax. Values of p

Primary aldosteronism (PA), a significant and curable cause of secondary hypertension, is seen in 5–10% of hypertensive patients, with its prevalence contingent upon the severity of the hypertension. The principal aetiologies of PA include bilateral idiopathic hypertrophy (BIH) and aldosterone-producing adenomas (APAs), while the less frequent causes include unilateral hyperplasia, familial hyperaldosteronism (FH) types I-IV, aldosterone-producing carcinoma, and ectopic aldosterone synthesis. This condition, characterised by excessive aldosterone secretion, leads to augmented sodium and water reabsorption alongside potassium loss, culminating in distinct clinical hallmarks: elevated aldosterone levels, suppressed renin levels, and hypertension. Notably, hypokalaemia is present in only 28% of patients with PA and is not a primary indicator. The association of PA with an escalated cardiovascular risk profile, independent of blood pressure levels, is notable. Patients with PA exhibit a heightened incidence of cardiovascular events compared to counterparts with essential hypertension, matched for age, sex, and blood pressure levels. Despite its prevalence, PA remains frequently undiagnosed, underscoring the imperative for enhanced screening protocols. The diagnostic process for PA entails a tripartite assessment: the aldosterone/renin ratio (ARR) as the initial screening tool, followed by confirmatory and subtyping tests. A positive ARR necessitates confirmatory testing to rule out false positives. Subtyping, achieved through computed tomography and adrenal vein sampling, aims to distinguish between unilateral and bilateral PA forms, guiding targeted therapeutic strategies. New radionuclide imaging may facilitate and accelerate such subtyping and localisation. For unilateral adrenal adenoma or hyperplasia, surgical intervention is optimal, whereas bilateral idiopathic hyperplasia warrants treatment with mineralocorticoid antagonists (MRAs). This review amalgamates established and emerging insights into the management of primary aldosteronism.

Abstract Background False negative myocardial perfusion images on single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a substantial problem in the interpretation of MPI. To explore possible parameters from gated SPECT that could detected coronary artery disease (CAD) in patients with normal perfusion images, we retrospectively selected patients who underwent a 2-day Tc-99 m MIBI adenosine stress/rest MPI and a subsequent invasive coronary angiography. Gated SPECT parameters, including end systolic volume (ESV), end diastolic volume (EDV), left ventricular ejection fraction (LVEF), and transient ischemic dilation (TID) ratio of patients with and without CAD were compared and assessed for their respective diagnostic performance using receiver operating characteristics (ROC) area under the curve (AUC). Results Among 22 patients with normal perfusion images, 7 patients had CAD. Despite the small number of patients, we found significant differences between the ESV, the EDV, and the LVEF between patients with and without CAD. The analysis of ROC curve showed the stress ESV could excellently detect CAD (AUC = 0.900). The rest ESV, the stress EDV, the rest EDV, the stress LVEF and the rest LVEF could likewise perform well in the detection of CAD (AUC = 0.833, 0.819, 0.790, 0.862, and 0.838, respectively). In contrast, the change in LVEF and the TID ratio (AUC = 0.667 and 0.524, respectively) did not seem as reliable as other parameters. Optimal cutoffs for detection of CAD in patients with normal perfusion images from our study were ≥ 20.0 mL for the stress ESV, ≥ 71.0 mL for the stress EDV, ≤ 66.3 EF units for the stress LVEF, ≥ 18.0 mL for the rest ESV, ≥ 67.0 mL for the rest EDV and ≤ 70.0 EF unit for the rest LVEF. Conclusions Gated SPECT parameters could facilitate detection of CAD in patient with normal perfusion images on Tc-99m MIBI MPI. These parameters should be carefully interpreted to improve diagnostic accuracy and reduce false negative MPI.

Parathyroidectomy is the treatment of choice for primary hyperparathyroidism when the clinical criteria are met. Although bilateral neck exploration is traditionally the standard method for surgery, minimally invasive parathyroidectomy (MIP), or focused parathyroidectomy, has been widely accepted with comparable curative outcomes. For successful MIP, accurate preoperative localization of parathyroid lesions is essential. However, no consensus exists on the optimal approach for localization. Currently, ultrasonography and technetium-99m-sestamibi–single photon emission computed tomography/computed tomography are widely accepted in most cases. However, exact localization cannot always be achieved, especially in cases with multiglandular disease, ectopic glands, recurrent disease, and normocalcemic primary hyperparathyroidism. Therefore, new modalities for preoperative localization have been developed and evaluated. Positron emission tomography/computed tomography and parathyroid venous sampling have demonstrated improvements in sensitivity and accuracy. Both anatomical and functional information can be obtained by combining these methods. As each approach has its advantages and disadvantages, the localization study should be deliberately chosen based on each patient’s clinical profile, costs, radiation exposure, and the availability of experienced experts. In this review, we summarize various methods for the localization of hyperfunctioning parathyroid tissues in primary hyperparathyroidism.

Objective To investigate the diagnostic value of xSPECT/CT-based tomographic fusion imaging in children with bone metastases. Methods Clinical and imaging data of 152 children with suspected bone metastases examined in our department were collected. All children underwent whole-body bone imaging, xSPECT/CT, and SPECT/CT tomographic fusion imaging. xSPECT/CT and SPECT/CT tomographic fusion images were compared and analyzed to evaluate the diagnostic value of xSPECT/CT tomographic fusion imaging in children with bone metastases. The diagnostic confidence of nuclear medicine physicians of two methods was also compared. Results The sensitivity, specificity, and accuracy of xSPECT/CT tomographic fusion imaging in the diagnosis of bone metastases in children were 93.3%, 91.5%, and 92.8%, respectively; the sensitivity, specificity, and accuracy of SPECT/CT tomographic fusion imaging in the diagnosis of bone metastases in children were 85.7%, 85.1%, and 85.5%, respectively. xSPECT/CT tomographic fusion imaging could improve the diagnostic confidence of nuclear medicine physicians and the difference was statistically significant [5 （2-5） vs. 3 （2-4）, P < 0.05]. Conclusion xSPECT/CT tomographic fusion imaging can effectively enhance the diagnostic confidence and diagnostic efficacy of nuclear medicine physicians in the diagnosis of bone metastases in children, which can help to diagnose bone metastases in children at an early stage, and further improve their clinical prognosis.

Objective To evaluate the diagnostic efficacy of triple‐phase bone scanning and the temporal impact of prosthesis implantation on the diagnostic efficacy of triple‐phase bone scanning for periprosthetic joint infection (PJI). Methods Patients who were admitted to our hospital for joint pain and dysfunction after total joint arthroplasty between 2014 and 2020 were retrospectively included. Triple‐phase bone scanning was performed, and the blood pool images were evaluated to obtain the semi‐quantitative criteria. The patients were then grouped into six groups according to the time interval from index primary arthroplasty to triple‐phase bone scanning. We examined whether there were significant differences in sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy between the groups. Results Overall, 66 patients who underwent total hip arthroplasty (THA) and 74 patients who underwent total knee arthroplasty (TKA) were analyzed. No significant differences were observed between visual analysis and semi‐quantitative measurement in terms of sensitivity, specificity, PPV, NPV, and accuracy. For patients with a time interval from prosthesis implantation to bone scanning of >1 year, visual analysis had a higher PPV (100%) in patients who underwent THA and the use of semi‐quantitative criteria had a higher NPV (85.7%) in patients who underwent TKA. Conclusion The semi‐quantitative criteria showed no advantages in the diagnosis of PJI. In addition, triple‐phase bone scanning demonstrated good clinical diagnostic efficacy when the time interval from prosthesis implantation to bone scanning was >1 year.

KP46 (tris(hydroxyquinolinato)gallium(III)) is an experimental, orally administered anticancer drug. Its absorption, delivery to tumours, and mode of action are poorly understood. We aimed to gain insight into these issues using gallium-67 and gallium-68 as radiotracers with SPECT and PET imaging in mice. [67Ga]KP46 and [68Ga]KP46, compared with [68Ga]gallium acetate, were used for logP measurements, in vitro cell uptake studies in A375 melanoma cells, and in vivo imaging in mice bearing A375 tumour xenografts up to 48 h after intravenous (tracer level) and oral (tracer and bulk) administration. 68Ga was more efficiently accumulated in A375 cells in vitro when presented as [68Ga]KP46 than as [68Ga]gallium acetate, but the reverse was observed when intravenously administered in vivo. After oral administration of [68/67Ga]KP46, absorption of 68Ga and 67Ga from the GI tract and delivery to tumours were poor, with the majority excreted in faeces. By 48 h, low but measurable amounts were accumulated in tumours. The distribution in tissues of absorbed radiogallium and octanol extraction of tissues suggested trafficking as free gallium rather than as KP46. We conclude that KP46 likely acts as a slow releaser of gallium ions which are inefficiently absorbed from the GI tract and trafficked to tissues, including tumour and bone.

Objective(s):The normal range of the frequency of antral contractions, similar to other gastric motility parameters, are different depending on the population and the test meal. We, therefore, conducted the analysis to establish the normal ranges for the frequency of antral contractions derived from dynamic antral scintigraphy (DAS) following an Asian-styled solid meal in Thai healthy volunteers.Methods:We retrospectively analyzed the data from the study on normal gastric emptying values. The dynamic scintigraphic images had been obtained in a 45 degree left anterior oblique view during the first 32 minutes following the ingestion of a 267-kcal steamed rice, a technetium-99m-labeled microwaved egg and 100 mL of water. A polynomial normalization model was used to analyze and to calculate the frequency of antral contractions. The data analysis was repeated by the same operator 1 month apart to assess reproducibility.Results:Data of 18 volunteers (10 males and 8 females) were eligible for analysis. The mean±SD of the frequencies of the antral contractions were 3.06±1.08 cycles/min on the first and 3.04±1.10 cycles/min on the second analysis. Comparison of the two analyses revealed a moderate agreement (ICC=0.632, 95% CI 0.329-0.818) without significant difference (p-value=0.942). No significant effect of gender, menstruation status, smoking or age was demonstrated in this study.Conclusion:DAS is a non-invasive technique that can measure the frequency of antral contractions. The technique is reproducible and consistent. Future study may be required to assess the effect of gender, menstruation status, smoking and age.

At present, one of the difficulties in the clinical diagnosis and treatment of tumors is to find specific targets and highly selective targeted inhibitors. Fibroblast activation protein (FAP) is a type Ⅱ transmembrane serine protease of the proline oligopeptidase family. A large number of studies have shown that FAP is overexpressed in cancer associated fibroblasts (CAFs) of various tumor entities, and plays important a role in the growth, invasion, metastasis, angiogenesis and immune escape of tumor cells. This suggesting that FAP may become a specific target for tumor diagnosis and treatment. In addition to being highly expressed in inflammation and fibrosis-related diseases, FAP is not normally expressed in normal tissues and organs of adults, so radionuclide-labeled FAP inhibitors have low background activity and can obtain high-contrast images. This article mainly describes the research progress of radionuclide-labeled small molecule FAP inhibitors in terms of affinity, selectivity, structure-activity relationship, in vivo metabolism, and clinical research of FAP inhibitors, in order to benefit clinical diagnosis and treatment.

Background: Recent research on photon detection has led to the introduction of a silicone photomultiplier (SiPM) that operates at a low voltage and is insensitive to magnetic fields. Objective: This work aims to model a scintillation camera with a SiPM sensor and to evaluate the camera reconstructed images from gamma ray projection data.Material and Methods: The type of study in this research is experimental work and analytical. The scintillation camera, modelled from an SiPM sensor array SL4-30035, coupled with a scintillation material Caesium Iodide doped with Thallium (CsI(Tl)), is used in the experimental part. The performance of the camera was evaluated from reconstructed images by a back-projection technique of a radioactive source Caesium-137 (Cs-137). Results: The experiments conducted with a 1 µCi Cs-137 radioactive source have revealed that the bias voltage (Vbias) of the SiPM needs to be set to 27.8 V at an operating temperature between 43 °C to 44 °C. The radioactive source has to be placed within a 1 cm distance from the sensor to obtain the optimum projection data. Finally, the back-projection technique for image reconstruction with linear interpolation pre-processing has revealed that the Ram-Lak filter produces a better image contrast ratio compared to others. Conclusion: This research has successfully modelled a scintillation camera with SiPM that was able to reconstruct images with an 86.4% contrast ratio from gamma ray projection data.

Background: UTI (urinary tract infection) is a leading case of renal scarring. Most of nephrons are found in kidney cortex, so it is important for early diagnosis of scarring. In this study, we investigated if scarring affects GFR (glomerular filtration rate) and serum level of creatinine through dual multipurpose 99mTc-GH (99mTc-Glucoheptonate) scintigraphy in patients with UTI. Methods: During this study 21 patients with UTI were studied by 99mTc-GH scan. For performing scintigraphy, the patient was injected by 370-555 MBq of 99mTc-GH and studied through two steps including dynamic (immediately after injection) and static (2-3h after injection) phases. The results were evaluated by appropriate analytical methods. Moreover, five patients were studied by both 99mTc-DMSA/GH (99mTc-dimercaptosuccinic acid and 99mTc-Glucoheptonate) to show 99mTc-GH scan is beneficial for detection of additional problems. Results: The results showed that there is an association between right/left kidney scarring and related GFR. Furthermore,, the odds of decreased right and left kidney GFR with scarring is 12.64 and 11.89 times more than normal kidney, respectively. Also, there is a significant association between renal scarring and serum level of creatinine. The study showed that the odds of increased serum level of creatinine in patients with scarring are 6.75 times more than patients without scarring. Moreover, the survey of five patients with both 99mTc-DMSA/GH scans showed 99mTc-GH could be helpful with diagnosis of some renal problems as well as scarring. Conclusion: Through this study by 99mTc-GH, it was demonstrated that kidney glomerular filtration rate and serum level of creatinine are associated with renal scarring. Furthermore, it was shown that 99mTc-GH scintigraphy could detect dilatation and abstraction of collection system in addition to renal scarring through static/dynamic renal scintigraphy.

Purpose. This work aimed at evaluating the possibility of performing renal exams of dynamic renal (DRS) and static renal (SRS) scintigraphy on the same day (one-day protocol, ODP), exams that are currently performed in two days. Approach. 25 infants (50 kidneys) of both genders, aged 8.4 ± 5.9 years, underwent an F+20 DRS protocol with [99mTc]TcDTPA2- followed by [99mTc]TcDMSA2- administration for the performance of SRS images at 3, 6 and 24 h. Dynamic images (DRS) were classified as dilated (D), undetermined (U), and non-dilated (P). Static images (SRS) were classified as: depressed in accented degree (DA); depressed in moderate degree (DM); depressed in mild degree (DL) and normal (NL). Results. Out of the 25 patients (50 kidneys), 7 (14 kidneys) were excluded by functional exclusion, hence 18 patients (36 kidneys) were clinically compared regarding their static images after 3, 6 and 24 h, resulting in 33.0% of dilated and 66.7% non-dilated. Only two patients of the dilated group were classified as obstructed. At the group with non-dilated and dilated but non-obstructed kidneys, 100% of them had the same clinical classification at 6 and 24 h images. Conclusions. Performance of both DRS and SRS exams in a single day for pediatric patients, when medical requests are carried out jointly, is feasible in a population with or without dilatation, when the difference between dynamic and static images is of at least 6 h. Due to the small number of obstructed kidneys in this study, further evaluation in this population is needed.

Abstract Background Common cold symptoms may be mitigated by products in caplet, nasal spray, and oral solution formulations, although variations exist in the bioavailability of the active ingredients contained within these products. Rapid gastric emptying (GE) of these active ingredients is important for reducing the delay between drug absorption and onset of cold symptom relief. Hot drink cold remedies are associated with greater comfort and may enhance the bioavailability of active ingredients. The objective of this study was to characterize the gastrointestinal transit of powder (reconstituted in hot water) and caplet formulations of commercially available multisymptom cold medications. Methods This was an open-label, single-dose, parallel-group study. Healthy male adults under fasted conditions were randomized 1:1 to receive a single dose of radiolabeled Theraflu Daytime Severe Cold and Cough powder for oral solution or radiolabeled Theraflu ExpressMax Daytime Severe Cold and Cough caplet. External gamma scintigraphy was utilized to monitor GE and intestinal transit of two radiolabeled drug formulations. Results A total of 28 participants completed the study. The mean ± SE GE onset times were 1.1 ± 0.3 min and 8.5 ± 1.8 min for powder and caplet formulations, respectively. The mean ± SE GE completion times were 121 ± 13 min and 65 ± 13 min, respectively. Despite the similar mean times to GE25%, the powder had later mean GE50% (23 ± 3.0 vs 16 ± 3.2 min, respectively) and GE90% (85 ± 12 vs 36 ± 9 min, respectively) than caplets. Caplets had a shorter overall GE half-life, lower total gastric exposure, and faster transit time through the small intestine versus the powder formulation. No serious safety events were observed. Conclusion The results of this study in healthy male adults suggest that the Theraflu powder formulation had a more rapid GE onset but longer time to GE completion than the caplet formulation. Trial registration ClinicalTrials.gov NCT03415243

Background/Aim. Gastric emptying (GE) scintigraphy provides a physiologic and noninvasive measurement of GE. Although GE scintigraphy has been standardized, preparing a meal is still complex and not practical in daily routine. The aim of the study was to prepare a simple, practical, and easily standardizable semisolid meal and investigate its role in estimating the GE function in of rabbits. Methods. In the first part of the study (basal condition), the mixture of the macroaggregated albumin (MAA) labeled with 37 MBq (1 mCi) of technetium-99m (99mTc) and 40 g of barium sulfate (1g/mL) was applied to animals via a nasogastric catheter. A series of images (frame/min, 60 min) in the anterior and posterior projections were dynamically acquired, and the motion was corrected after the radiopharmaceutical application. A few days later, the same rabbits were scanned under the same protocol after a 1 mg atropine injection to simulate gastroparesis condition. Eleven rabbits were included according to inclusion and exclusion criteria, and a total of twenty-two imaging data sets were analyzed for quantification. Results. In the basal study, total counts of the mixture decreased from 87,800.83 ± 12,622.76 to 42,733.14 ± 6,591.53 at 30 min and to 13,684.19 ± 1,774.90 at 60 min, and these decreases were statistically significant (p = 0.003). Emptying percentages were 51.39 ± 0.78% at 30 min and 84.32 ± 1.56 at 60 min and were statistically significant (p = 0.003). After intravascular atropine sulfate injection, total counts of the mixture decreased from 84,508.78 ± 11,871.48 to 64,995.18 ± 9,298 at 30 min and to 53,507.17 ± 7,258.98 at 60 min, and these decreases were statistically significant (p = 0.003). Emptying percentages were 23.10 ± 1.11% at 30 min and 36.63 ± 1.42 at 60 min and were statistically significant (p = 0.003). The difference between basal and post-atropine sulfate gastric emptying percentage at 30th (p = 0.003) and 60th (p = 0.003) min was statistically significant. Conclusion. The meal, used in this study, is non-nutrient, fatty-free, and semisolid and is easy to prepare and administer. Due to its semisolid nature, it offers a chance to evaluate the quantification of regional and total GE as well as the separate roles of the fundus and antrum.

Thyroglossal duct cysts, which are the most frequently encountered congenital cervical anomalies in children, occur due to embryologic remnants of the thyroglossal duct. Although diagnosis may be challenging, clinicians can be aided by imaging and fine-needle aspiration biopsies. We describe the clinical management of a two-year-old boy with a thyroglossal duct cyst mimicking a goitre on a pertechnetate thyroid scan.

Abstract Background Biliary atresia (BA) and neonatal hepatitis (NH) are the two major causes of neonatal cholestasis (NC). However, both conditions had entirely different therapeutic schedule and prognosis. Considering BA as a surgical emergency, it is pretty important to accurately differentiate the two entities. The aim of the study is to evaluate the diagnostic utility of hepatobiliary scintigraphy (HBS) using a semi-quantitative technique as well as 15-point histopathological scoring system in differentiating BA from NH. Results The sensitivity, specificity, and overall accuracy of HBS in the diagnosis of BA was 90.5%, 80%, and 83.6%, respectively. The median values of kidney-liver ratio (KLR), intestinal-liver ratio (ILR), and background-liver ratio (BLR) were significantly higher in patients with BA, while that of the liver-kidney ratio (LKR) was significantly lower in cases with BA. Moreover, KLR had the largest area under curve (AUC); advocates it to be the best of the semi-quantitative parameters that can predicts BA. Histopathological scoring using a cutoff point ≥ 7 was helpful in discriminating BA from NH with 85.7% sensitivity, 95% specificity and 91.8% accuracy. Conclusions HBS is a non-invasive diagnostic tool frequently used in diagnosis of BA, yet it has a relatively low specificity. To overcome this challenge, we kindly recommend the use of semi-quantitative parameters that could possibly improve the accuracy of HBS for diagnosing BA. Additionally, the use of 15-point scoring for liver biopsy was useful.

Jeongmin Lee,1 Jeonghoon Ha,2 Sang-Kuon Lee,3 Hye Lim Park,4 Sung-Hoon Kim,5 Dong-Jun Lim,2 Jung Min Lee,1 Sang-Ah Chang,1 Moo Il Kang,2 Min-Hee Kim1 1Division of Endocrinology and Metabolism, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; 2Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; 3Division of Pancreatobiliary Surgery, Department of Surgery, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; 4Division of Nuclear Medicine, Department of Radiology, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea; 5Division of Nuclear Medicine, Department of Radiology, Seoul St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of KoreaCorrespondence: Min-Hee KimDivision of Endocrinology and Metabolism, Department of Internal Medicine, Eunpyeong St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of KoreaTel +82-2-2030-4348Fax +82-2-2030-4641Email benedict@catholic.ac.krPurpose: Primary aldosteronism (PA) is mainly comprised of aldosterone-producing adenoma and bilateral idiopathic adrenal hyperplasia. Current guidelines recommend adrenal venous sampling (AVS) as a gold standard method to classify the subtypes. However, because of technical challenges in AVS including invasiveness of AVS and a wide range of success rate for cannulation, it is not uncommon that appropriate decisions could not be made depending on AVS. The aim of this study is to elucidate the proper role of I‑131‑6β‑iodomethyl‑norcholesterol (NP-59) scintigraphy in management of PA.Patients and Methods: Between January 2009 and October 2018, patients with PA were retrospectively reviewed for the study. Five patients were included in the study who had NP-59 scintigraphy with non-conclusive AVS results or without AVS. We described the clinical outcome of patients in whom clinical decisions were made according to NP-59 scintigraphy results.Results: Patients in the presenting cases were diagnosed for PA. AVS, the most reliable test to identify unilateral APA, were not applicable because of hypersensitivity to contrast dye (patient 1), and use of antiplatelet agents after acute cerebral infarction (patient 2). NP-59 scintigraphy was performed in patients 3 and 4 whose result of AVS and CT scan were inconsistent. In patient 5, who had bilateral adrenal adenomas (two in the left and one in the right adrenal gland), both unsuccessful catheterization and coexistence of cortisol overproduction made AVS results unreliable.Conclusion: Based on clinical outcomes of these case series, it is noticeable that NP-59 scintigraphy could play a substantial role in management of PA in selected cases.Keywords: hyperaldosteronism, angiography, aldosterone, radionuclide imaging

Background/Aim. The most frequent therapeutic method for achalasia is balloon dilatation (BD). Esophageal scintigraphy is potentially the most convenient method for the evaluation of achalasia by quantifying esophageal transit. The aim of this study was to present the results of esophageal scintigraphy (ES) in achalasia treated by BD for a long period of time, from 1997 to 2016, and to set parameters suitable for predicting treatment outcomes. Methods. Two-phase ES in anterior projection was performed. The first phase involved swallowing 10 mL of water with 18.5 MBq 99mTc in a supine position. The second phase was performed in a standing position after swallowing 100 mL of water. The retention index (RI) of esophageal radioactivity was calculated after the imaging using registered esophageal and gastric counts. ES was performed in 52 patients (34 males and 18 females, aged 22–75 years, the median age 44 years) before and after BD. In 31 patients, only two scintigraphies were performed. In the remaining 21 patients, follow-up and repeated scintigraphies were continued including the patients with therapeutic failure and repeated BD. BD was repeated in 8 patients, and those were followed up and evaluated over time. Modified BD was performed with Rigiflex balloon dilators. Results. A typical scintigraphic finding in the supine position was passive esophageal filling without the evidence of motility, and in most patients, 43 of them (83%), radionuclide elimination in the stomach was absent. Evaluating values before and long after the first BD, it was shown that certain values of RI indicated remission or relapse of the disease. The RI difference higher than 50% after BD was a reliable indicator of a longer remission. The age and gender of patients had no impact on the outcome of dilatation, but younger patients were with a higher risk of early failure (6 patients during the first year after BD). ES showed that the first BD was initially successful in 50 patients and after the follow-up in 41 (79%) patients. Conclusion. A two-phase supine/standing ES is most suitable for diagnosing and the follow-up of achalasia. RI represents an important parameter for the evaluation and prediction of therapeutic response. The RI difference of more than 50% after BD is a reliable predictor of a longer remission. Age and gender have no impact on dilatation outcome, but patients younger than 40 years have a higher risk of early therapeutic failure.

Background/Aim. There is a constant and dramatic in-crease in hip and knee prosthetic implantations worldwide. However, a decrease in the percentage of failed (infected) prosthetic implantations is not significant (0.5% up to 2%). The real challenge is whether prosthetic joint loosening was caused by aseptic inflammation or by infection. The aim of the present study was to attempt to distinguish sterile inflammation from infection in patients with a painful hip or knee prosthetic joint. Another objective was to determine the accuracy of cumulative bone scintigraphy with methylenediphosphonate (MDP) and ciprofloxacin in diagnosis of periprosthetic joint infection (PJI). Methods. Three-phase bone scintigraphy with 99mTc-MDP and 99mTc-ciprofloxacin was used. The patient selection criterion for this study was a suspicion of PJI followed by painful and limited movement of the prosthetic joint, accompanied by elevated unspecific inflammatory factors. Forty five patients with 39 implanted hips and 24 knee prostheses were included and evaluated. All prosthetic joints were examined (although some of them were asymptomatic) and underwent plain radiography. An average time span between the two nuclear medicine imaging procedures was 3–5 days. Three-phase 99mTc-MDP bone scintigraphy was performed first. Scintigraphy with 99mTc-ciprofloxacin was necessarily involved calculation of the accumulation index. The obtained results were confirmed by microbiological findings as a gold standard. Statistical analysis of the results was performed using SPSS version 20 software (descriptive statistics, χ2-test). Sensitivity, specificity, and predictive values were also calculated. Results. Microbiologically confirmed PJI was found in 16 out of 39 hip prostheses. Positive scintigraphy was obtained in 15 out of 39 prosthetic hip joints. PJI was found using scintigraphy of the knee, and microbiologically con-firmed in all 13 out of 24 suspected joints. Estimated sensitivity/specificity of 99mTc-MDP bone scintigraphy alone (for both joints) was 90%/69%, for 99mTc-ciprofloxacin scintigraphy it was 93%/97%, and for cumulative results it was 96.5%/97%. Conclusion. Cumulative 99mTc-MDP scintigraphy with 99mTc-ciprofloxacin scintigraphy increases the ability of differentiation between aseptic loosening and PJI, with high accuracy of 97%.

ABSTRACT Introduction: secondary forms of lymphedema may occur as consequence of tumors, surgeries, radiotherapy, trauma and infections. Degloving injuries are severe and infrequent forms of trauma, with avulsion at the level of muscular fascia, and consequent injury of the lymphatic system. Objective: to evaluate the alterations in lymphatic circulation in patients being victims of circumferential degloving injuries in the lower limbs, using lymphoscintigraphic. Patients and Methods: retrospective analysis of the cases treated in the period from 2010 to 2016. Segmental, circumferential and unilateral injuries with involvement of the lower limbs were included. Lymphoscintigraphy was performed after a minimum interval of 12 months after the end of treatment. The non-injured lower limb was used as control. The Kleinhans Semiquantitative Index (KSI) was used for the semiquantitative evaluation of the lymphoscintigraphic findings. Results: eighteen patients were evaluated, six of whom were female and 12 were male. The mean age was 28.11 years. The average vertical extension of the circumferential traumatized segment was 29.33cm. The injured area presented variations of 5 to 15% of the body surface, with an average of 8.95%. Lymphoscintigraphy was performed after an average interval of 22.55 months. Alterations were observed on the traumatized limb (TL) in 13 patients. All control limbs (CL) were normal. The mean KSI observed in TL was 8.32, while in CL, the average value was 0.58 (p

Purpose: To report a single surgeon experience with one year follow-up after open ureteroplasty with buccal mucosa graft (OUBMG) in the rare situation of long segment proximal ureteral strictures. Materials and Methods: Four patients with long segment proximal ureteral stricture underwent OU-BMG between February and July 2017. Functional outcome was assessed by pre- and postoperative serum creatinine, ultrasound and renal scintigraphy as well as patient reported outcomes. Results: Four patients with an average stricture length of 4 cm underwent OU-BMG between February and July 2017. No major postoperative complications occurred. Retrograde uretero-pyelography 6 weeks postoperatively revealed a watertight anastomosis followed by immediate emptying of the renal pelvis and ureter in all four patients. Ureteroscopy at this time showed a wide lumen with well-vascularized pink mucosa. After a mean follow-up time of 12.5 (12–14) months, postoperative serum creatinine was unimpaired. Renal scintigraphy revealed no signs of renal obstruction. With regard to intraoral surgery, no difficulties with mouth opening or intraoral dryness or numbness were reported. Conclusions: For patients with long segment ureteral strictures OU-BMG is a safe technique with excellent surgical and functional outcomes. Hence, the application of this technique should be encouraged and regarded as one of the standard options in case of this rare problem.

Abstract Background 4-(N-(S-glutathionylacetyl)amino) phenylarsonous acid (GSAO) when conjugated at the γ-glutamyl residue with fluorophores and radio-isotopes is able to image dead and dying cells in vitro and in vivo by binding to intracellular 90-kDa heat shock proteins (hsp90) when cell membrane integrity is compromised. The ability to image cell death has potential clinical impact especially for early treatment response assessment in oncology. This work aims to assess the biodistribution and tumour uptake of diethylene triamine pentaacetic acid GSAO labelled with 111In ([111In]In-DTPA-GSAO) and 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid GSAO labelled with 67Ga ([67Ga]Ga-DOTA-GSAO) in a murine subcutaneous tumour xenograft model and estimate dosimetry of [67Ga]Ga-DOTA-GSAO. Results There was good tumour uptake of both [111In]In-DTPA-GSAO and [67Ga]Ga-DOTA-GSAO (2.44 ± 0.26% injected activity per gramme of tissue (%IA/g) and 2.75 ± 0.34 %IA/g, respectively) in Balb c nu/nu mice bearing subcutaneous tumour xenografts of a human metastatic prostate cancer cell line (PC3M-luc-c6). Peak tumour uptake occurred at 2.7 h post injection. [111In]In-DTPA-GSAO and [67Ga]Ga-DOTA-GSAO demonstrated increased uptake in the liver (4.40 ± 0.86 %IA/g and 1.72 ± 0.27 %IA/g, respectively), kidneys (16.54 ± 3.86 %IA/g and 8.16 ± 1.33 %IA/g) and spleen (6.44 ± 1.24 %IA/g and 1.85 ± 0.44 %IA/g); however, uptake in these organs was significantly lower with [67Ga]Ga-DOTA-GSAO (p = 0.006, p = 0.017 and p = 0.003, respectively). Uptake of [67Ga]Ga-DOTA-GSAO into tumour was higher than all organs except the kidneys. There was negligible uptake in the other organs. Excretion of [67Ga]Ga-DOTA-GSAO was more rapid than [111In]In-DTPA-GSAO. Estimated effective dose of [67Ga]Ga-DOTA-GSAO for an adult male human was 1.54 × 10− 2 mSv/MBq. Conclusions [67Ga]Ga-DOTA-GSAO demonstrates higher specific uptake in dead and dying cells within tumours and lower uptake in normal organs than [111In]In-DTPA-GSAO. [67Ga]Ga-DOTA-GSAO may be potentially useful for imaging cell death in vivo. Dosimetry estimates for [67Ga]Ga-DOTA-GSAO are acceptable for future human studies. This work also prepares for development of 68Ga GSAO radiopharmaceuticals.

Background/Aim. Ultrasonography is a cheap, easily available and convenient method for diagnosis. The aims of this study were: to determine the utility of ultrasonography for preoperative identification and localization of enlarged parathyroid glands (PTG) in patients with different forms of hyperparathyroidism (HPT); to examine the frequency of PTG detection in patients previously non-suspected for HPT but having symptoms relevant to the disease; to determine sensitivity and positive predictive value (PPV) of ultrasonography for identification of PTG in HPT and to compare obtained results with those obtained by scintigraphy. Methods. This investigation was designed as a retrospective–prospective study. The total number of patients undergoing ultrasonography prior to surgery was 179 and the number of those subjected to scintigraphy, mostly by the 201Tl/99mTc method, was 112. The patients (52 male, 128 female) were divided into the following four groups: group A – patients with primary (p)HPT (n = 78); group B – patients with secondary (s)HPT (n = 47); group C – patients with tertiary (t)HPT (n = 13); group D – patients with unrecognized (u)HPT, but with anamnestic data implying the disease (n = 42). High resolution ultrasonography was performed by a single experienced observer. Diagnosis of HPT was based on characteristic clinical and biochemical parameters. Final proof of HPT diagnosis was surgery followed by histopathological examination. Results. Ultrasonography detected enlarged PTG in 93.85% of total patients, whereas scintigraphy uncovered 75.89% of positive cases (p < 0.05). The total number of positive PTG detected by ultrasonography was 211 vs 225 detected by surgery (sensitivity – 95.9%; PPV – 99.4%). Histopathology confirmed the predominance of adenoma in the A and D groups in comparison with the B group of patients having PTG hyperplasia. The group C was characterized by the presence of adenomas in hyperplastic PTG. The mean size of PTG measured by ultrasonography was 17.59 ± 8.0 mm (n = 164) vs 18.36 ± 8.54 mm (n = 179) measured after surgery. Ultrasonography proved itself as an accurate technique in all HPT groups, regarding its high sensitivity (range 93.6–100%) and PPV (95.6–100%). In contrast, scintigraphy was shown to be less reliable, especially in the sPTH group (sensitivity: 51.7%; PPV: 78.4%). Conclusion. Ultrasonography is more sensitive and accurate method for pre-operative localization of PTG in comparison with 201Tl/99mTc scintigraphy. It can be also efficiently used for detection of PTG and diagnosis of HPT in patients previously not suspected for this disease.

The literature review examines the historical aspects and key issues of the clinical application of new radiopharmaceuticals (RF) for positron emission tomography (PET). The gold standard for measuring effective renal plasma flow is p-[18F] fluorohippurate ([18F] PFH) due to its structure close to p-aminoimpurate one. [18F] FDS is a new potential tracer for the diagnosis of acute renal failure. PET tracers Re (CO) 3 ([18F] FEDA) and [18F] PFH are effective as surrogate markers for the selection of patients for endoradiotherapy with a potential nephrotoxic profile, in patients with hematopoietic malignant tumours and prostate cancer. PET imaging of the kidneys and urinary system can be of additional importance in difficult clinical situations and provide effective support in making diagnostic decisions, in particular in paediatric patients. Further scientific diagnostic research should focus on the synthesis of new radiopharmaceuticals that will have ideal properties for renal functional imaging, low binding to plasma proteins, high metabolic stability and low hepatobiliary clearance.

Background To provide insight into bone turnover, quantitative measurements of bone remodeling are required. Radionuclide studies are widely used in clinical care, but have been rarely used in the exploration of the bone in preclinical studies. We describe a bone planar scintigraphy method for frequent assessment of bone activity in mice across the growing period. Since repeated venous radiotracer injections are hardly feasible in mice, we investigated the subcutaneous route. Methods Repeated 99mTc-hydroxymethylene diphosphonate (HMDP) tracer bone planar scintigraphy studies of the knee region and µCT to measure femur growth rate were performed in eight mice between week 6 and week 27 of life, i.e., during their growth period. Three independent investigators assessed the regions of interest (ROI). An index was calculated based on the counts in knees ROI (normalized by pixels and seconds), corrected for the activity administered, the decay between administration and imaging, and individual weights. Results A total of 93 scintigraphy studies and 85 µCT were performed. Repeated subcutaneous tracer injections were well tolerated and allowed for adequate radionuclide studies. Mean scintigraphic indexes in the knees ROI decreased from 87.4 ± 2.6 × 10−6 counts s−1 pixel−1 MBq−1 g−1 at week 6 to 15.0 ± 3.3 × 10−6 counts s−1 pixel−1 MBq−1 g−1 at week 27. The time constant of the fitted exponential decay was equal to 23.5 days. As control mean femur length assessed by µCT increased from 12.2 ± 0.8 mm at week 6 to 15.8 ± 0.2 mm at week 22. The time constant of the fitted Gompertz law was equal to 26.7 days. A correlation index of −0.97 was found between femur growth and decrease of bone tracer activity count between week 6 and 24. Conclusion This methodological study demonstrates the potential of repeated bone planar scintigraphy in growing mice, with subcutaneous route for tracer administration, for quantitative assessment of bone remodeling.

Pharmacokinetic assessment of drug disposition processes in vivo is critical in predicting pharmacodynamics and toxicology to reduce the risk of inappropriate drug development. The blood–brain barrier (BBB), a special physiological structure in brain tissue, hinders the entry of targeted drugs into the central nervous system (CNS), making the drug concentrations in target tissue correlate poorly with the blood drug concentrations. Additionally, once non-CNS drugs act directly on the fragile and important brain tissue, they may produce extra-therapeutic effects that may impair CNS function. Thus, an intracerebral pharmacokinetic study was developed to reflect the disposition and course of action of drugs following intracerebral absorption. Through an increasing understanding of the fine structure in the brain and the rapid development of analytical techniques, cerebral pharmacokinetic techniques have developed into non-invasive imaging techniques. Through non-invasive imaging techniques, molecules can be tracked and visualized in the entire BBB, visualizing how they enter the BBB, allowing quantitative tools to be combined with the imaging system to derive reliable pharmacokinetic profiles. The advent of imaging-based pharmacokinetic techniques in the brain has made the field of intracerebral pharmacokinetics more complete and reliable, paving the way for elucidating the dynamics of drug action in the brain and predicting its course. The paper reviews the development and application of imaging technologies for cerebral pharmacokinetic study, represented by optical imaging, radiographic autoradiography, radionuclide imaging and mass spectrometry imaging, and objectively evaluates the advantages and limitations of these methods for predicting the pharmacodynamic and toxic effects of drugs in brain tissues.

Burning mouth syndrome (BMS) is a chronic disorder characterized by a burning sensation in the oral cavity, often accompanied by xerostomia, with no relevant clinical or laboratory findings. This study aimed to investigate diagnostic values of quantitative parameters of salivary gland scintigraphy for BMS in patients with xerostomia. A total of 164 patients who underwent salivary gland scintigraphy for the workup of xerostomia were retrospectively reviewed. All patients were classified into patient groups with primary BMS, secondary BMS, and non-specific xerostomia. From salivary gland scintigraphy, 22 quantitative parameters were calculated and their diagnostic values were assessed based on the area under the receiver operating characteristic curve (AUC) values. Among salivary gland scintigraphy parameters, uptake speed in the left submandibular gland showed the highest AUC value (0.647) for detecting BMS and pre-stimulatory oral activity showed the highest AUC value (0.710) for detecting primary BMS. A salivary gland scintigraphy scoring system based on these two parameters further enhanced the diagnostic ability, demonstrating AUC values of 0.731 for BMS and 0.782 for primary BMS. These results suggest a potential diagnostic value of the quantitative parameters of salivary gland scintigraphy for detecting BMS in patients with xerostomia.

The use of molecular imaging technologies for brain imaging can not only play an important supporting role in disease diagnosis and treatment but can also be used to deeply study brain functions. Recently, with the support of reporter gene technology, optical imaging has achieved a breakthrough in brain function studies at the molecular level. Reporter gene technology based on traditional clinical imaging modalities is also expanding. By benefiting from the deeper imaging depths and wider imaging ranges now possible, these methods have led to breakthroughs in preclinical and clinical research. This article focuses on the applications of magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), and positron emission tomography (PET) reporter gene technologies for use in brain imaging. The tracking of cell therapies and gene therapies is the most successful and widely used application of these techniques. Meanwhile, breakthroughs have been achieved in the research and development of reporter genes and their imaging probe pairs with respect to brain function research. This paper introduces the imaging principles and classifications of the reporter gene technologies of these imaging modalities, lists the relevant brain imaging applications, reviews their characteristics, and discusses the opportunities and challenges faced by clinical imaging modalities based on reporter gene technology. The conclusion is provided in the last section.

Abstract Atherosclerotic plaque is the primary cause of cardiovascular disorders and remains a therapeutic hurdle for the early intervention of atherosclerosis. Traditional clinical strategies are often limited by surgery‐related complications or unsatisfactory effects of long‐term drug administration. Inspired by the plaque‐binding ability of platelets, a biomimic photodynamic therapeutic system is designed to mitigate the progression of atherosclerotic plaques. This system is composed of photosensitizer‐loaded upconversion nanoparticle cores entrapped in the platelet membrane. The platelet membrane coating facilitates specific targeting of the therapeutic system to macrophage‐derived foam cells, the hallmark, and main component of early stage atherosclerotic plaques, which is firmly confirmed by in vivo fluorescent and single‐photon emission computed tomography/computed tomography (SPECT/CT) radionuclide imaging. Importantly, in vivo phototherapy guided by SPECT/CT imaging alleviates plaque progression. Further immunofluorescence analysis reveals foam cell apoptosis and ameliorated inflammation. This biomimic system, which combines plaque‐binding with radionuclide imaging guidance, is a novel, noninvasive, and potent strategy to mitigate the progression of atherosclerotic plaque.

Introduction:Low-pass filters eliminate noise, and accordingly improve the quality of filtered back-projection (FBP) in the reconstruction of single photon emission computed tomography (SPECT) images. This study aimed at selection of an optimum low-pass filter for FBP reconstruction of SPECT images of small structures. Material and Methods:Spheres A, B, and C (16 mm, 12 mm, and 11 mm in diameter, respectively) attached to capillary stems were filled with technetium-99m solution (activity concentration 300 kBq/mL). They were then mounted inside a Jaszczak Phantom forming a V-shaped structure. The phantom was then filled with distilled water. Two-dimensional (2D) projections were acquired on 128 128 pixels using a Siemens E-Cam dual-head gamma camera. The Parzen, Shepp-Logan, Low Pass Cosine filters (cut-off frequencies: 0.2-0.9), and Butterworth filter (order: 1-9; cut-off frequencies: 0.3-0.9) were employed during FBP reconstruction. The line command of ImageJ software was used to draw the point spread functions of acquired 2D transaxial central slices and for the measurement of their full-width at half-maximum (FWHM). Results:The FWHM of 2D central image slices of spheres A, B, and C reconstructed using a Butterworth filter measured 20, 20, and 10 pixels, respectively. In comparison, the reconstructed images using the Parzen, Low Pass Cosine, and Shepp-Logan filters measured to 27, 25 and, 22 pixels for sphere A, 24, 22, 20 pixels for B, and 22, 20, 18 pixels for C, respectively. Conclusion: The low-pass filters successfully suppressed noise during the FBP reconstruction of SPECT images of small structures. Accordingly, the Butterworth is a suitable choice.

The aims of this study were to determine whether post transplant renal scan performed at around 1 week can predict graft failure, and to identify the best predictive factors among easy-to-measure variables.

Splenosis refers to autotransplantation of splenic tissue into intraabdominal, intrathoracic or even any other parts of body and occurs after splenic trauma or splenectomy. Hepatic splenosis is usually incidental found during imaging workup. It can mimic other hypervascular mass because it presents vivid and heterogeneous enhancement representing that of splenic tissue. So far, about 20 cases of intrahepatic splenosis have been described in the literature. Herein we report a case of intrahepatic splenosis mimicking hepatocellular carcinoma in a patient with liver cirrhosis. The patient was finally diagnosed on the basis of specific radionuclide imaging.

BackgroundPostoperative routine radioiodine (RAI) treatment is currently debated for patients with low-risk differentiated thyroid carcinoma (DTC) patients. If performed, a low 131I activity (i.e., 1 to 2 GBq) is recommended with the aim to ablate thyroid remnant and facilitate subsequent follow-up by thyroglobulin measurement. The purpose of this study was to evaluate the relationship between postsurgical technetium-99m (99mTc)-pertechnetate scintigraphy and the rate of successful remnant ablation after low activity radioiodine ablation in patients with DTC.MethodsEnrolled were 193 patients with low risk DTC who underwent total thyroidectomy and RAI ablation with a fixed 1.1 GBq activity of 131I. 99mTc-pertechnetate scans were done and thyrotropin stimulated thyroglobulin (sTg) levels measured just before ablation. Ablation effectiveness was assessed 6 to 12 months later by sTg measurement, neck ultrasound and diagnostic whole body scan.ResultsA negative 99mTc-perthecnetate scans was the best predictor of successful ablation (P

The intermediate-risk category of papillary thyroid cancer (PTC) comprises heterogeneous patients within a wide range of stages and varied care management. Understanding the risk features of recurrence observed after the initial therapy should be emphasized. We aimed to evaluate the prognostic significance of radioactive iodine-avid lymph nodes observed during the initial treatment of patients with PTC that were considered to be at intermediate risk. Data on patients with intermediate-risk PTC treated from 2012 to 2018 were retrospectively reviewed. Post-therapeutic SPECT/CT (Rx SPECT/CT) was evaluated in the enrolled patients. The clinical, pathologic, and incidence of radioiodine-avid (RAI-avid) lymph node metastasis (mLN) on Rx SPECT/CT were reviewed, and risk factors related to recurrent disease were analyzed. After a median follow-up of 37.26 (30.90, 46.33) months, structural persistent/recurrent disease was detected in 9.81% (36/367) of patients with intermediate-risk tumors. The incidence of recurrence was higher in patients who demonstrated RAI-avid mLN after the initial therapy than in those who did not (p < 0.001). In a multivariate Cox proportional hazard regression analysis, RAI-avid mLN appeared to be a robust risk factor for recurrent disease after the initial therapy (HR: 8.967, 95% CI: 3.433–23.421, p = 0.000). RAI-avid mLN is a significant risk factor for recurrent intermediate-risk PTC after the initial treatment.

Abstract Objective: To report the case of a pediatric patient with bilateral hydronephrosis due to vesicoureteral junction obstruction (VUJO) that was treated non-surgically and to discuss the approach of this anomaly. Case Description: A 25-month-old boy was referred without complaints for consultation due to prenatal ultrasound showing kidneys with cysts. He was under antibiotic prophylaxis. No family history of kidney disease and/or inherited disorders was reported. Renal ultrasound (RUS) at 2 days of life showed bilateral hydronephrosis, thus ruling out the possibility of kidney cystic disease. Dynamic renal scintigraphy (DTPA) showed marked retention of the marker in the pyelocaliceal system bilaterally, with little response to diuretic drug. He was maintained under antibiotic prophylaxis, when a new RUS showed bilateral ureteral dilatation, abrupt stenosis in the ureterovesical transition region (0.2 cm caliber), moderate bilateral hydronephrosis, and slight renal cortical thickness, confirming the diagnosis of VUJO. At 2 years and 10 months of age, DTPA showed hydronephrosis and ureteral stasis in both kidneys secondary to stenosis at the vesicoureteral junction (VUJ) level, with preservation of kidney function and slow degree of emptying. We opted for a non-surgical approach. RUS at 10 years of age showed significant improvement of all parameters, with ureteral transverse diameter of 9 mm, preserved VUJ, and age-appropriate bilateral kidney development. Comments: VUJO is a major cause of prenatal hydronephrosis and can trigger a deterioration of kidney function. Its treatment is still controversial but should take into account the importance of clinical follow-up and serial imaging evaluation.

Purpose: To investigate whether a correlation exists between the semi-quantitative breast-specific gamma imaging (BSGI) findings and dynamic contrast-enhanced (DCE) MRI parameters assessed by a computer-aided evaluation program. Materials and Methods: Semi-quantitative index of the lesion to non-lesion (L/N) ratio in BSGI and DCE-MRI parameters was assessed by a computer-aided evaluation program, where 47 cases of invasive breast cancer were obtained. Correlations between the L/N ratio and DCE-MRI parameters were assessed by a computer-aided evaluation program. Tumor diameter (cm), angio-volume (cc), degree of initial peak enhancement (%), persistent enhancement proportion (%), and washout enhancement proportion (%) were analysed. The relationships between the L/N ratio and DCE-MRI parameters were evaluated by a univariate and multivariate regression analysis. Results: The mean L/N ratio of the 47 tumors was 3.63 ± 2.19 (range: 1–13.1). The L/N ratio was higher in tumors with larger diameters (p < 0.001), increased angiovolume (p < 0.001), higher degree of initial peak enhancement (p = 0.005) and increased washout enhancement proportion (p = 0.004). In the multivariate regression analysis, angio-volume (cc) and washout enhancement proportion (%) were associated with L/N ratio (p = 0.007 and p = 0.024, respectively). Conclusion: There was a correlation between the semi-quantitative L/N ratio in BSGI and DCE-MRI parameters assessed by a computer-aided evaluation program for breast cancer.

Abstract Purpose: To compare the influence of two metallic implants in the diagnosis of periprosthetic infection using 99m technetium-labeled ceftizoxime. Methods: Twenty rats were randomly divided into four groups, which received sterile and contaminated titanium and stainless steel implants. After 3 weeks, scintilographic images were obtained using a gamma chamber. Radioactivity counts were obtained for the region of interest (ROI) on the operated and non-operated paws. Results: Groups A, B, and C showed homogenous distribution of the radiopharmaceutical. Hyper uptake was observed in the operated paw from group D. The ROI target count was higher in the two groups with stainless steel implants. Among the control groups, the count was higher in the stainless steel group. Furthermore, among the contaminated groups, the uptake was higher in the stainless steel group, with a significant difference. The target: non-target ratio was significantly lower in the control and contaminated groups with both titanium and stainless steel, but the comparison between control groups and contaminated groups was only significant in the former. The cpm/g observed after a decay of 48h showed statistically significant differences between groups. Conclusion: Different biomaterials used in implants have an influence on the results of scintigraphy with 99mTc-CFT.

Introduction. Secondary hypertension is a relatively common form of hypertension in childhood with renovascular hypertension being responsible for 5%–10% of all arterial hypertensions in children. An early diagnosis of renovascular hypertension is important when considering an appropriate treatment of hypertension that may prevent or slow further progression of kidney damage. To validate the usefulness of a captopril renal scintigraphy in hypertensive children, we report a case of a 16-year-old female patient with a history of hypertension as a result of fibromuscular dysplasia. Case report. The patient was asymptomatic with elevated blood pressure revealed by a routine physical examination. Laboratory tests showed the increased levels of plasma renin activity with the normal levels of aldosteron. The renal ultrasound was normal. The Doppler of the renal arteries showed no significant differences of resistive index. A renal captopril scintigraphy was performed, including two day study protocol, the baseline study followed by another captopril study several days later. The scintigraphy showed the abnormal baseline and captopril renogram curve of the right kidney with significant cortical retention of radiotracer after angiotensin-converting enzyme inhibition. Following the captopril scintigraphy a renovasography was obtained confirming the presence of a 2 mm long circular narrowing of the right renal artery. It was immediately treated resulting in a significant expansion of the lumen. Conclusion. The captopril renal scintigraphy allows non-invasive functional testing in a selected group of hypertensive children, which can either confirm or rule out the existence of hemodynamically significant renal artery stenosis.