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This study was designed to assess the influence of coronary endothelial function and the serial changes of dual myocardial single photon emission computed tomography (SPECT) imaging in transient left ventricular (LV) apical ballooning.We evaluated 35 consecutive patients (8 men and 27 women; mean age, 71 +/- 13 years) with transient LV apical ballooning. All patients underwent coronary angiography with acetylcholine provocation 1 month after onset. Iodine 123 beta-methyl-p-iodophenyl-pentadecanoic acid (BMIPP) and thallium 201 dual myocardial SPECT was serially performed on day 1 of admission and 1 month and 6 months later. In 8 of 35 patients (23%), epicardial coronary spasm was induced by acetylcholine infusion. At the peak acetylcholine dose (100 microg), diffuse coronary vasoconstriction developed in 19 of 35 patients (54%). Of 19 patients, 13 had diffuse coronary vasoconstriction with chest pain and ST-segment depression. The total defect score of I-123 BMIPP and Tl-201 SPECT showed marked perfusion-fatty acid metabolic mismatches (13.7 +/- 3.6 vs 8.7 +/- 2.3, P.001) at the LV apex during the acute phase but few mismatched areas (2.1 +/- 1.1 vs 1.5 +/- 1.4, P = not significant) at 6 months.Transient LV apical ballooning might be caused by stress-induced coronary epicardial spasm or endothelial dysfunction, resulting in myocardial stunning.

Resumen —Introduccion El proposito del presente estudio fue describir las variables que se asocian a la isquemia silente en los pacientes a los que se les realiza ergometria con gammagrafia de perfusion miocardica y presentan defectos reversibles de la perfusion. Metodos Se analizan retrospectivamente de forma cuantitativa las gammagrafias con Tl201-SPECT de 522 pacientes que presentaban defectos de perfusion total o parcialmente reversibles durante la prueba de esfuerzo maxima. Se relaciono la aparicion de angina con el tamano del defecto de perfusion y la presencia de diferentes factores de riesgo. Resultados En 412 (73 %) pacientes la isquemia fue silente. En 176 (33 %) pacientes la ergometria fue electricamente positiva. No hubo diferencias en el tamano del defecto de perfusion entre los pacientes con y sin angina (27 ± 12 vs 27 ± 14), pero en los pacientes que presentaron angina durante la ergometria el grado de reversibilidad fue mayor sobre todo en el territorio de la arteria descendente anterior (ADA) (56 ± 40 vs 45 ± 40 p Conclusiones Una elevada proporcion de los pacientes con defectos de la perfusion reversibles en la gammagrafia tuvieron isquemia silente. En los pacientes con angina el grado de reversibilidad en el territorio de la ADA fue mayor. La isquemia silente es mas frecuente en los pacientes con IAM previo.

We have shown that the diagnostic accuracy of quantitative single photon emission computed tomography (SPECT) thallium 201 myocardial perfusion imaging is lower in women than in men and that much of the difference can be explained by the smaller size of the left ventricle in women. Therefore attempts at improving the accuracy of myocardial perfusion imaging in women should focus on the problem of lower accuracy in patients with small chamber size. We evaluated two strategies for this: size- and gender-based normal databases and inverse filtering with the Wiener filter.We identified 618 patients undergoing exercise SPECT TI-201 who either had a low pre-test probability of coronary artery disease or had catheterization-documented disease. Their images were analyzed on the basis of gender and chamber size: both gender and size- and gender-based normal databases were created. The studies were analyzed quantitatively, and the accuracy was evaluated by use of the area under the receiver operating characteristic (ROC) curve. Chamber size was significantly lower in women (size index 69+/-22 women vs 96+/-28 men; P.0001). The accuracy of myocardial perfusion imaging was lower in women compared with men (ROC area: 0.92+/-0.01 men vs 0.85+/-0.03 women; P = .03), and there was an even greater difference in accuracy between patients with large versus small chamber size (ROC area: 0.94+/-0.01 large vs 0.81+/-0.03 small; P.001). There was no improvement in the diagnostic accuracy either in women or in patients with small chamber size when a size- and gender-based normal database, Wiener filter, or the Wiener filter with a size- and gender-based normal database was used.The left ventricular chamber size in women is smaller than that in men. There is a significant difference in the accuracy of quantitative SPECT TI-201 between men and women and an even greater difference between patients with large versus small chamber size. Neither size- and gender-based databases nor Wiener filtering significantly improves accuracy in women or in patients with small chamber size.

In this report the usefulness of Tl-201 SPECT and modified retention images in the differentiation of lung cancer and postobstructive collapse was studied. Two-phase Tl-201 SPECT was performed in 20 lung cancer lesions in which postobstructive collapse was suspected on CT. Retention imaging was done afterward. Three types of Tl-201 images were compared with the bolus CT images. Bolus CT differentiated lung cancer from postobstructive collapse in 7 of the 20 lesions (35%). Tl-201 SPECT differentiated the two conditions in 9 of 20 lesions (45%) on early Tl-201 SPECT and in 13 of 20 lesions (65%) on delayed imaging. With modified retention images, differentiation was possible in 13 of 20 lesions (65%). By combining delayed Tl-201 SPECT and modified retention images, lung cancer alone could be demonstrated in 18 of 20 lesions (90%). Combined delayed Tl-201 SPECT and modified retention images were more effective than bolus CT in delineating the extent of lung cancer in the presence of postobstructive collapse.

Thallium-201 single-photon emission computed tomography (Tl-201 SPECT) and F-18 fluorodeoxyglucose positron emission tomography (FDG PET) are accurate and excellent methods for detecting malignant tumors and related metabolic abnormalities. However, there are still some limitations in clinical application. The major limitation of SPECT is poor image resolution. PET is less sensitive for detecting lesions of the urinary system adjacent to the bladder because of bladder radioactivity. Both T1-201 and F-18 FDG PET often provide less information than x-ray computed tomography (CT) about the anatomic landmarks needed to precisely locate lesions. Recent development of multimodality image registration and fusion has been shown to be an excellent tool to resolve these drawbacks. The authors present a rare case of residual cervical carcinoma with bladder invasion, which was detected by fusion imaging of Tl-201 SPECT and FDG PET with CT. This noninvasive image technique may become a valuable alternative to identify bladder invasion in cervical cancer.

To evaluate treatment efficacy, Tl-201 SPECT was performed in three patients with pancreatic cancer. In all of the patients, the degree of Tl-201 uptake by tumor, evaluated from the tumor-liver uptake ratio of Tl-201 activity, correlated well with alterations in serum level of a tumor marker (CA 19-9, DUPAN-2) after treatment. One of the patients showed no tumor shrinkage on CT after treatment; however, Tl-201 SPECT demonstrated reduced uptake in the tumor coupled with a decreased level of CA 19-9. These results suggest that Tl-201 SPECT may become a new tool for assessing the efficacy of treatment in pancreatic cancer.

This study aimed to determine whether Tl-201 single photon emission CT (SPECT) is potentially useful in differentiating false-positive fluorodeoxyglucose positron emission tomography (FDG-PET) findings caused by osteoradionecrosis (ORN) from recurrent head and neck cancer after radiotherapy.Five patients were recruited. Dual-phase FDG-PET and dual-phase Tl-201 SPECT were performed for each patient.All 5 patients proved to have ORN without recurrent cancer. By visual interpretation, the results were 4 positive versus 1 negative for PET, and 4 negative versus 1 positive for Tl-201 SPECT. The Tl-201 SPECT clarified 3 of the 4 false-positive PETs to be ORN. Dual-phase semiquantitative studies showed decreased standardized uptake value (SUV) over time in 3 of the 4 false-positive PETs and decreased lesion/background ratio over time in the false-positive Tl-201 SPECT.The Tl-201 SPECT may help clarify suspected false-positive FDG uptake caused by ORN. Dual-phase FDG-PET and dual-phase Tl-201 SPECT may also have some value.

Objectives: To compare with histopathological findings the findings of prostate cancer imaging by SPECT method using Tl-201 as a tumor seeking agent. Methods: The study comprised 59 patients (age range 51-79 years, mean age 65.3 ± 6.8 years) who were planned to have transrectal ultrasonography (TRUS)-guided biopsies due to suspicion of prostate cancer between April 2011 and September 2011. Early planar, late planar and SPECT images were obtained for all patients. Scintigraphic evaluation was made in relation to uptake presence and patterns in the visual assessment and to Tumor/Background (T/Bg) ratios for both planar and SPECT images in the quantitative assessment. Histopathological findings were compatible with benign etiology in 36 (61%) patients and malign etiology in 23 (39%) patients. Additionally, comparisons were made to evaluate the relationships between uptake patterns,total PSA values and Gleason scores. Results: A statistically significant difference was found between the benign and malignant groups in terms of uptake in planar and SPECT images and T/Bg ratios and PSA values. No statistically significant difference was found between uptake patterns of planar and SPECT images and Gleason scores in the malignant group. Conclusions: SPECT images were superior to planar images in the comparative assessment. Tl-201 SPECT imaging can provide an additional contribution to clinical practice in the diagnosis of prostate cancer and it can be used in selected patients.

A semi-automatical method for apical echocardiographic and myocardial Tl-201 SPECT images registration is proposed. It uses oriented ellipses extracted from the LV myocardial center line in all images of the two modalities in one acquisition direction. These geometrical models allow SPECT-slice selection and 2D-registration, leading to a fused image involving the echographic image and its corresponding SPECT slice. The method was qualitatively evaluated with six patients, showing the potential usefulness of this tool in the study of myocardial ischemia and viability disease. >

The authors evaluated the ability of dual SPECT with Tc-99m MIBI and Tl-201 chloride to differentiate malignant and benign solitary pulmonary nodules smaller than 3 cm in diameter. Forty-three patients had solitary pulmonary nodules smaller than 3 cm in diameter based on the findings of chest CT. All patients underwent dual-isotope SPECT with Tc-99m MIBI and Tl-201 chloride. Regions of interest were placed over the tumors (T) and contralateral normal lung tissue (N) on one coronal SPECT view, and T:N ratios and retention indices were calculated. The sensitivities of early and delayed Tc-99m MIBI SPECT and early and delayed Tl-201 chloride SPECT for differentiating malignant and benign lesions were 44%, 48%, 56%, and 52%, respectively. The corresponding specificity rates were 44%, 56%, 25%, and 31%, respectively, and corresponding accuracy rates were 44%, 51%, 44%, and 44%, respectively. There were no statistically significant differences between malignant and benign lesions in the early and delayed T:N ratios for Tc-99m MIBI and Tl-201 chloride and the retention index for Tc-99m MIBI. However, the retention index using Tl-201 chloride in malignant lesions was significantly higher (P < 0.01) than that in benign lesions. Analysis of semiquantitative parameters of the T:N ratio and retention index from Tc-99m MIBI SPECT appears to have little or no value for differentiating malignant from benign solitary pulmonary nodules smaller than 3 cm in diameter. However, the retention index using Tl-201 chloride seems to be a better parameter for differentiating between these malignant and benign lesions.

The aim of the study was to test the clinical value and the impact of attenuation-corrected Tl-201 SPECT (AC), using a moving Gd-153 line source, on the extent and severity of perfusion abnormalities in a clinical setup of patients planned to undergo coronary angiography because of clinically suspected coronary artery disease. 107 patients, planned to undergo coronary angiography, were included in our study. In each patient, AC and NC (non-corrected)-Tl-201 SPECT was performed. AC and NC were evaluated visually as well as by a 31-segment-semiquantitative analysis and correlated with angiographic results. Patients were assigned to two different groups: group A with angina and no previous cardiac infarction or intervention (Specificity NC 68.7 %, AC 83.9 %) and group B with known CAD because of previous myocardial infarction or intervention (Specificity NC 91.3 %, AC 100 %). The extent and the severity of perfusion abnormalities were significantly influenced using AC by demonstrating significantly less abnormal and less severe abnormal segments in the segmental analysis compared to NC, especially for the vascular territory of the LAD and RCA.

Recurrent lung cancer was detected by TI-201 SPECT showing mediastinal and hilar accumulations when the x-ray CT showed recurrence. Recurrence was confirmed by x-ray CT 3 months later. The use of TI-201 SPECT as a complementary modality to other radiological studies for the postoperative assessment of lung cancer should be encouraged.

Gating of resting Tl-201 SPECT to evaluate myocardial viability Is now clinically feasible. Two cases are presented to illustrate the additional information of wall motion and wall thickening obtained from gating. This additional information may improve the classification of viable myocardium and requires further study.

Gated myocardial SPECT may be useful for the simultaneous evaluation of myocardial perfusion and left ventricular function. The authors present a case of unstable angina pectoris with no apparent perfusion abnormality but impaired regional wall motion on gated TI-201 SPECT at rest. Although image quality of gated TI-201 SPECT is inferior to Tc-99m sestamibi SPECT, the results of this case suggest that gated TI-201 SPECT might be useful for the evaluation of viable but dysfunctional myocardium such as in unstable angina pectoris when a perfusion abnormality is obscure at rest. This protocol can be applied to patients in whom exercise is contraindicated in pharmacologic stress studies.

A case of left breast cancer which was detected incidentally by Tl-201 SPECT performed to evaluate the status of myocardial perfusion, is reported. Both stress and redistribution Tl-201 SPECT clearly delineated the tumor. It was confirmed later as scirrhous carcinoma of the breast.