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Fubin Wang Department of Ophthalmology, Shanghai Bright Eye Hospital, Shanghai, 200336, People’s Republic of ChinaCorrespondence: Fubin Wang, Department of Ophthalmology, Shanghai Bright Eye Hospital, 899 Maotai Road, Changning District, Shanghai, 200336, People’s Republic of China, Email wfb_528@163.comIntroduction: Spontaneous focal hemorrhage of optic disc in peripapillary hyperreflective ovoid mass-like structures (PHOMS) is rare. This study reports the image features of two cases of spontaneous hemorrhage of an optic disc in PHOMS.Methods: Case 1: A 51-year-old woman complained of visual fatigue for 1 week. Small patchy hemorrhage was observed in the optic disc of the right eye. Case 2: A 17-year-old female presented with complaints of experiencing floaters in the left eye for a duration of 1 day. Small patchy hemorrhage was observed in the left optic disc. The patients underwent the color fundus photograph (CFP), fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT), optical coherence tomography angiography (OCTA), and Minimum intensity projection (Min-IP) images.Results: Case 1: The right eye showed a small patchy hemorrhage of optic disc. PHOMS on SD-OCT of both eyes exhibited an ovoid shape and manifested as peripapillary hyperreflective bright regions on en-face Min-IP image, the active blood flow signal of PHOMS was detected on SD-OCT/OCTA and FAF revealed a hypofluorescent. The optic cup-to-disc (C/D) ratio of both eyes was 0.06, respectively. Case 2: Small patchy hemorrhage was observed in the left optic disc and FAF showed hypofluorescence. PHOMS on SD-OCT of the left eye showed an ovoid shape and manifested as peripapillary hyperreflective bright regions on en-face Min-IP image, the active blood flow signal of PHOMS was detected on SD-OCT/OCTA. C/D in the right eye was 0.4.Conclusion: Spontaneous focal hemorrhage of optic disc may occur in PHOMS. The space-occupying effect of PHOMS may lead to compression of surrounding tissues, resulting in the optic disc congestion and a reduced C/D ratio, thereby involving the microvascular system of the optic disc.Keywords: peripapillary hyperreflective ovoid mass-like structures, spontaneous hemorrhage, minimum intensity projection, spectral-domain optical coherence tomography

Fubin Wang,* Aijun Wang,* Xiaoyan Leng, Lin Yong Department of Ophthalmology, Shanghai Bright Eye Hospital, Shanghai, People’s Republic of China*These authors contributed equally to this workCorrespondence: Fubin Wang, Shanghai Bright Eye Hospital, 899 Maotai Road, Changning District, Shanghai, 200336, People’s Republic of China, Email wfb_528@163.comIntroduction: This study presents a rare case of multiple evanescent white dot syndrome (MEWDS) with atypical electrooculogram (EOG) findings, as well as abnormal en-face images of minimum intensity projection (Min-IP) and the en-face inner segment/outer segment-ellipsoid complex.Methods: A 25-year-old female patient presented with painless visual impairment and photopsia in her right eye for a duration of two days. Multimodal imaging was employed including color fundus photography (CFP), fundus autofluorescence (FAF), spectral-domain optical coherence tomography (SD-OCT), and optical coherence tomography angiography (OCTA), and en-face images of Min-IP and the en-face inner segment/outer segment-ellipsoid complex were performed.Results: In the right eye, multifocal small white spots were observed surrounding the posterior pole and optic disc of retina with the granular appearance of the fovea. FAF displayed of hyperfluorescence. SD-OCT appearance of MEWDS demonstrated primarily disrupted ellipsoid zone (EZ), photoreceptor outer segments, and interdigitation zone (IZ) complex within the fovea. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP exhibited hyperreflective spots in the right eye. In the left eye, interestingly, hyperreflective spots were also observed on the en-face image of the inner segment/outer segment-ellipsoid complex. EOG revealed an Arden ratio of 2.5 for the right eye, while the left eye exhibited an Arden ratio of 1.7.Conclusion: The en-face image of the inner segment/outer segment-ellipsoid complex in MEWDS exhibits aberrant features and it is noteworthy that a similar alteration may occur in the fellow eye. Further investigation is required to explore the relationship between MEWDS and EOG. The en-face images of the inner segment/outer segment-ellipsoid complex and Min-IP may help to elucidate the pathogenesis of MEWDS.Keywords: multiple evanescent white dot syndrome, EOG, inner segment/outer segment-ellipsoid complex, minimum intensity projection, multimodal imaging

Fubin Wang Department of Ophthalmology, Shanghai Bright Eye Hospital, Shanghai, 200336, People’s Republic of ChinaCorrespondence: Fubin Wang, Shanghai Bright Eye Hospital, 899 Maotai Road, Changning District, Shanghai, 200336, People’s Republic of China, Email wfb_528@163.comIntroduction: Optic disc melanocytoma (ODMC) with peripapillary hyperreflective ovoid mass-like structures (PHOMS) is rare. This study reports a case of the characteristics of multimodal imaging and Minimum intensity projection (Min-IP) images.Methods: A 25-year-old male patient was referred to our hospital due to the presence of a dark pigmented tumor located in the optic disc area of his left eye. The patient exhibited normal pupillary reactions and had a best corrected visual acuity of 1.0 (decimal) in both eyes. This patient underwent multimodal retinal imaging examination including color fundus photograph (CFP), B-scan ultrasonography, Fundus autofluorescence (FAF), SD-OCT (spectral-domain optical coherence tomography), OCTA (optical coherence tomography angiography), en-face Min-IP image and fluorescein angiography (FA).Results: CFP revealed a slightly elevated mass lesion in the inferior quadrant of the left optic disc, the lesion appeared black to dark brown in color. B-scan ultrasonography of the left eye confirmed the presence of a hyperechoic small dome-shaped lesion. Fundus autofluorescence (FAF) analysis revealed complete hypofluorescence in this area. SD-OCT (spectral-domain optical coherence tomography) and OCTA (optical coherence tomography angiography) with Min-IP were performed over the tumor and its surrounding areas. SD-OCT showed an elevated tumor mass arising from the optic disc with increased reflectivity. PHOMS appeared ovoid in shape on B-scan OCT image. PHOMS appeared peripapillary hyperreflective bright areas on en-face Min-IP image corresponding to PHOMS on B-scan OCT image. The fluorescein angiography (FA) showed the staining of PHOMS. A diagnosis of optic disc melanocytoma with PHOMS was established prompting the patient to be advised for regular follow-up.Conclusion: The optic disc melanocytoma with PHOMS is a rare benign ocular lesion that requires minimal active intervention, but demands a lifetime follow-up. The multimodal imaging and Min-IP images have clinical diagnostic value.Keywords: optic disc melanocytoma, peripapillary hyperreflective ovoid mass-like structures, minimum intensity projection, OCT, multimodal imaging

Non-confocal split-detection imaging reveals the cone photoreceptor inner segment mosaic in a plethora of retinal conditions, with the potential of providing insight to ageing, disease, and response to treatment processes, in vivo, and allows the screening of candidates for cell rescue therapies. This imaging modality complements confocal reflectance adaptive optics scanning light ophthalmoscopy, which relies on the waveguiding properties of cones, as well as their orientation toward the pupil. Split-detection contrast, however, is directional, with each cone inner segment appearing as opposite dark and bright semicircles, presenting a challenge for either manual or automated cell identification. Quadrant-detection imaging, an evolution of split detection, could be used to generate images without directional dependence. Here, we demonstrate how the embossed-filtered quadrant-detection images, originally proposed by Migacz et al. for visualising hyalocytes, can also be used to generate photoreceptor mosaic images with better and non-directional contrast for improved visualisation. As a surrogate of visualisation improvement between legacy split-detection images and the images resulting from the method described herein, we provide preliminary results of simple image processing routines that may enable the automated identification of generic image features, as opposed to complex algorithms developed specifically for photoreceptor identification, in pathological retinas.

Purpose: This study aimed to observe the changes of venous continuity using the susceptibility weighted imaging-minimum intensity projection (SWI-MinIP) images in children with primary headache. Methods: The headache types were classified following the International Headache Society's diagnostic criteria. Patients with secondary headaches were excluded. The presence of asymmetric vasculature in SWI-MinIP images was visually assessed. Moreover, the relationship between headache patterns and asymmetric hypointense signals was analyzed. Results: In this single-center, retrospective study from 2016 to 2020, among 251 cases of primary headache (male/female, 108/143; mean age, 11.4 ± 4.0 years), 137 (54.6%), 75 (29.9%), and 39 (15.5%) patients had migraine, tension-type headache, and other primary headaches, respectively. On SWI-MinIP images, 14 (5.6%) patients showed an asymmetric venous pattern. All patients with SWI-MinIP asymmetry were included in the migraine group, accounting for 10.2% of patients with migraine. Five (35.7%) and nine (64.3%) patients were included in the aura and non-aura groups, respectively, without a significant difference in the frequency of asymmetric hypointense signals between the two groups (p = 0.325). All 14 patients with asymmetric hypervascularity had brain MRI within 12 h of headache onset. Ten (71.4%) of the 14 patients showed consistency between the laterality of headache and the hemisphere of predominant vascularity in SWI-MinIP. Conclusion: Patients with migraine had increased cerebral venous perfusion in the most involved region of the headache on the SWI-MinIP view on a 3.0 T scanner, which can be used as a qualitative indicator with low sensitivity and high specificity for the diagnosis of primary headache in the acute phase (< 12 h). [ABSTRACT FROM AUTHOR]

The objective of this study is to evaluate the feasibility of a disease-specific deep learning (DL) model based on minimum intensity projection (minIP) for automated emphysema detection in low-dose computed tomography (LDCT) scans. LDCT scans of 240 individuals from a population-based cohort in the Netherlands (ImaLife study, mean age ± SD = 57 ± 6 years) were retrospectively chosen for training and internal validation of the DL model. For independent testing, LDCT scans of 125 individuals from a lung cancer screening cohort in the USA (NLST study, mean age ± SD = 64 ± 5 years) were used. Dichotomous emphysema diagnosis based on radiologists' annotation was used to develop the model. The automated model included minIP processing (slab thickness range: 1 mm to 11 mm), classification, and detection maps generation. The data-split for the pipeline evaluation involved class-balanced and imbalanced settings. The proposed DL pipeline showed the highest performance (area under receiver operating characteristics curve) for 11 mm slab thickness in both the balanced (ImaLife = 0.90 ± 0.05) and the imbalanced dataset (NLST = 0.77 ± 0.06). For ImaLife subcohort, the variation in minIP slab thickness from 1 to 11 mm increased the DL model's sensitivity from 75 to 88% and decreased the number of false-negative predictions from 10 to 5. The minIP-based DL model can automatically detect emphysema in LDCTs. The performance of thicker minIP slabs was better than that of thinner slabs. LDCT can be leveraged for emphysema detection by applying disease specific augmentation. [ABSTRACT FROM AUTHOR]

Post mortem computed tomography (PMCT) can aid in localizing foreign bodies, bone fractures, and gas accumulations. The visualization of these findings play an important role in the communication of radiological findings. In this article, we present an algorithm for automated visualization of gas distributions on PMCT image data of the thorax and abdomen. The algorithm uses a combination of region growing segmentation and layering of different visualization methods to automatically generate overview images that depict radiopaque foreign bodies, bones and gas distributions in one image. The presented method was tested on 955 PMCT scans of the thorax and abdomen. The algorithm managed to generate useful images for all cases, visualizing foreign bodies as well as gas distribution. The most interesting cases are presented in this article. While this type of visualization cannot replace a real radiological analysis of the image data, it can provide a quick overview for briefings and image reports. [ABSTRACT FROM AUTHOR]

Non-confocal split-detection imaging reveals the cone photoreceptor inner segment mosaic in a plethora of retinal conditions, with the potential of providing insight to ageing, disease, and response to treatment processes, in vivo , and allows the screening of candidates for cell rescue therapies. This imaging modality complements confocal reflectance adaptive optics scanning light ophthalmoscopy, which relies on the waveguiding properties of cones, as well as their orientation toward the pupil. Split-detection contrast, however, is directional, with each cone inner segment appearing as opposite dark and bright semicircles, presenting a challenge for either manual or automated cell identification. Quadrant-detection imaging, an evolution of split detection, could be used to generate images without directional dependence. Here, we demonstrate how the embossed-filtered quadrant-detection images, originally proposed by Migacz et al. for visualising hyalocytes, can also be used to generate photoreceptor mosaic images with better and non-directional contrast for improved visualisation. As a surrogate of visualisation improvement between legacy split-detection images and the images resulting from the method described herein, we provide preliminary results of simple image processing routines that may enable the automated identification of generic image features, as opposed to complex algorithms developed specifically for photoreceptor identification, in pathological retinas., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Kalitzeos, Michaelides and Dubra.)

A 10‐year‐old female spayed Dachshund was referred with progressive coughing for 1 month. The dog was tentatively diagnosed with right middle lung torsion based on pleural effusion, vesicular emphysema, abruptly ending bronchus in consolidated right middle lung, and no contrast enhancement of the affected lobe on radiography and computed tomography (CT). There was no evidence of torsion upon thoracotomy, and histological examination confirmed lobar pneumonia. The CT images were reevaluated using minimum intensity projection and revealed normal bronchial courses. The minimum intensity projection technique can be to assist in evaluation of the bronchial tree for dogs with suspected lung lobe torsion and other pulmonary diseases. [ABSTRACT FROM AUTHOR]

Chest physicians need to be aware about MinIP images, as these are increasingly being used for the evaluation of a wide range of lung diseases in HRCT study of lungs. MinIP images highlight the areas with reduced CT attenuation in the lung parenchyma. This allows prompt and early diagnosis of cystic lung diseases or airway, vascular or parenchymal disorders, which manifest with hypoattenuation, mosaic attenuation or air trapping. MiniP images are therefore useful for accurate pre-operative planning and disease monitoring.

OBJECTIVE: To determine the diagnostic accuracy of multidetector computed tomography cholangiography in diagnosis of biliary tract obstruction keeping Endoscopic Retrograde Cholangiopancreatogram (ERCP) as gold standard. STUDY DESIGN: A Cross Sectional Validation Study PLACE AND DURATION: The study was done in the Department of Radiology, KRL Hospital Islamabad, from 1st may 2013 to 31st October 2013. METHODOLOGY: All patients included in the study underwent contrast enhanced CT scan using Toshiba Aquilion 64 slice CT scanner. Reformated cholangiographic images were produced using a workstation (Vitrea, version 3.9)Final multidetector computed tomography diagnosis was later on compared with ERCP done and reported by an endoscopy specialist. Both qualitative and quantitative variables were calculated. RESULTS: In our study two age groups i.e 20-40years and 41-60years were included, mean age was calculated as 36.81 +/- 9.72 years, with 57.27% were male and 42.73% were females. The frequency of biliary tract obstruction diagnosed on Endoscopic Retrograde Cholangio-Pancreatography (ERCP) was recorded in 60.91%. Diagnostic accuracy of MDCT cholangiography in diagnosis of biliary tract obstruction shows 55.45% true positive,2.73% false positive, 37.27% true negative and 5.45% false negative values. CONCLUSION: From study it can be concluded that MDCT cholangiography can be reliably used as tool in diagnosis of biliary tract obstruction in comparison with ERCP. [ABSTRACT FROM AUTHOR]

Objective. Micro-computed tomography (MCT) with alternative image reformatting techniques shows complex and detailed root canal anatomy. This study compared two-dimensional (2D) and 3D MCT image reformatting with standard tooth clearing for studying mandibular first molar mesial root canal morphology. Materials and methods. Extracted human mandibular first molar mesial roots ( n = 31) were scanned by MCT (Skyscan 1172). 2D thin-slab minimum intensity projection (TS-MinIP) and 3D volume rendered images were constructed. The same teeth were then processed by clearing and staining. For each root, images obtained from clearing, 2D, 3D and combined 2D and 3D techniques were examined independently by four endodontists and categorized according to Vertucci's classification. Fine anatomical structures such as accessory canals, intercanal communications and loops were also identified. Results. Agreement among the four techniques for Vertucci's classification was 45.2% (14/31). The most frequent were Vertucci's type IV and then type II, although many had complex configurations that were non-classifiable. Generally, complex canal systems were more clearly visible in MCT images than with standard clearing and staining. Fine anatomical structures such as intercanal communications, accessory canals and loops were mostly detected with a combination of 2D TS-MinIP and 3D volume-rendering MCT images. Conclusions. Canal configurations and fine anatomic structures were more clearly observed in the combined 2D and 3D MCT images than the clearing technique. The frequency of non-classifiable configurations demonstrated the complexity of mandibular first molar mesial root canal anatomy. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To compare the performance of MDCT, including multiplanar reformation (MPR) and minimum intensity projection (MinIP) images, with that of transaxial MDCT with MR cholangiography (MRC) in the preoperative evaluation of the longitudinal extent of bile duct cancer. Methods: Twenty-seven patients with surgically proven bile duct cancer, who had undergone preoperative multiphasic MDCT and MRC, were included. Two radiologists evaluated the MDCT set with MPR and MinIP images and the image set of transaxial MDCT with MRC, regarding the longitudinal extent of bile duct cancer. The results were compared with the surgical and pathology findings. Results: The area under the receiver operating characteristic curves of the MDCT set with MPR and MinIP images and the image set of transaxial MDCT with MRC for predicting the longitudinal extent of bile duct cancer, were 0.938, 0.923 and 0.839, 0.836 for both reviewers. The differences were not statistically significant for either image set or either reviewer. The sensitivity and specificity of the MDCT image set for detecting tumor involvement of the biliary second confluences or intrapancreatic segment were similar for both reviewers to those of transaxial MDCT with MRC. Conclusions: MDCT with MPR and MinIP images showed comparable diagnostic performance to that of transaxial MDCT with MRC for predicting the longitudinal extent of bile duct cancer. [Copyright &y& Elsevier]

Summary The objective of this pictorial essay is to highlight the key role of computed tomography scanning (CT scan), particularly minimum intensity projection (MinIP) reformation, with regards to the diagnosis of hypersensitivity pneumonitis (HP) and its contribution to patients' management. MinIP enhances detecting the characteristic CT scan features of HP, particularly air trapping and ground-glass opacities, features representing the bronchoalveolar lavage or biopsy core target zones to the clinician. [ABSTRACT FROM AUTHOR]

The development of multidetector row computed tomography (MDCT) has led to the acquisition of true isotropic voxels that can be postprocessed to yield images in any plane of the same resolution as the original axially acquired images. This, coupled with rapid MDCT imaging during peak target organ enhancement has led to a variety of means to review imaging information beyond that of the axial perspective. Postprocessing can be utilized to identify variant biliary anatomy to guide preoperative planning of biliary-related surgery, determine the level and cause of biliary obstruction and assist in staging of biliary cancer. Postprocessing can also be used to identify pancreatic ductal variants, visualize diagnostic features of pancreatic cystic lesions, diagnose and stage pancreatic cancer, and differentiate pancreatic from peripancreatic disease. [ABSTRACT FROM AUTHOR]

Abstract: Navigation is important in Computed Tomography Virtual Endoscopy (CTVE) functions. Existing navigation methods involve planning and pre-calculating of a fixed path before the viewpoint flight inside the targeted organs. This includes path construction, centering, smoothing and multi-branch processing. This paper proposes a 3D navigation method which was achieved by utilizing the compatibility of the 3D navigation and the ray casting 3D rendering method, without the necessity of planning and pre-calculating a fixed path, eliminating the multi-branch problems. In our 3D navigation method, the viewpoint direction and location are tracked in real time when the viewpoint is inside the organs. At the same time it presents and controls the direction changes and location changes of the viewpoint in x, y, z dimensions. With interactive control of the viewpoint, it can fly in any direction in 3D, not only along a fixed path, thus eliminating multi-branch problems. The viewpoint locations and directions will change smoothly and will be used to calculate the current scene of CTVE. Accelerated ray casting is used to render 3D scenes, which is compatible with the 3D navigation method. In Minimum Intensity Projection (MinIP) applications, if the conventional MinIP reconstruction method is used, realistic results cannot be achieved when they are rotated in multi-directions because the Computed Tomography (CT) images always contain empty regions surrounding the tissue regions. The conventional MinIP reconstruction algorithm always chalks up a minimum intensity voxel which relates to the empty regions instead of the tissue regions. To solve such valid voxel searching problems, seed-filling algorithms are used to fill the empty regions of each slice automatically. The empty voxels are labeled automatically and are avoided in MinIP calculation to gain correct results in all directions. [Copyright &y& Elsevier]

The objective was the evaluation of minimum intensity projections (MinIP) of 16-channel multidetector computed tomography (MDCT) data for the visualization of biliary ducts with magnetic resonance cholangiopancreatography (MRCP) as reference method. Twenty-five patients with biliary obstruction who received MDCT of the abdomen and MRCP without subsequent interventions were analysed. Coronal and axial MinIP were reconstructed from the MDCT-data. The evaluation of image quality and the quantitative comparison to MRCP was performed by two observers in consensus. The additional diagnostic value of MinIP compared with conventionally visualised MDCT was assessed by three independent observers. With MRCP as the reference method, MinIP was superior to conventional MDCT concerning the visualization of the extent of bile duct dilatation (r, 1.000 vs 0.699) and the correlation of diameter measurement (r, 0.979 vs 0.942). Subsidiary to conventional MDCT, MinIP revealed an improvement of visualization of the biliary system in 73% of cases. Concerning the additional diagnostic value, MinIP allowed for a better definition of the obstruction site in 13% of patients, and in one patient a change of diagnosis was observed. Thus, MinIP can improve the diagnostic assessment of biliary obstructions in MDCT imaging. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether sliding thin slab, minimum intensity projection (STS-MinIP) imaging is more advantageous than thin-section computed tomography (CT) for detecting and assessing emphysema. Objective quantification of emphysema by STS-MinIP and thin-section CT was defined as the percentage of area lower than the threshold in the lung section at the level of the aortic arch, tracheal carina, and 5 cm below the carina. Quantitative analysis in 100 subjects was performed and compared with pulmonary function test results. The ratio of the low attenuation area in the lung measured by STS-MinIP was significantly higher than that found by thin-section CT ( P < 0.01). The difference between STS-MinIP and thin-section CT was statistically evident even for mild emphysema and increased depending on whether the low attenuation in the lung increased. Moreover, STS-MinIP showed a stronger regression relation with pulmonary function results than did thin-section CT ( P < 0.01). STS-MinIP can be recommended as a new morphometric method for detecting and assessing the severity of emphysema. [ABSTRACT FROM AUTHOR]

A sliding thin slab, minimum intensity projection (STS-MinIP) is considered to be useful for detecting diseases that decrease lung attenuation. For evaluating these diseases, it would be useful to ascertain the lower limits of normal lung attenuation, allowing a division between normal and subnormal attenuation. However, normal lung attenuation may vary depending on respiratory status, anatomical position, and patient background factors. Our aim was to determine whether the lower limits of lung attenuation, without airways, in asymptomatic subjects using STS-MinIP varies under different conditions. The study subjects were 43 volunteers without pulmonary symptoms. STS-MinIP was performed at full inspiration and full expiration at three levels of the lung. The lower limits of lung attenuation were compared among the three lung levels and between full inspiration and full expiration, the sexes, age groups, smokers and nonsmokers, and the right and left lungs. The lower limits of lung attenuation had significantly different Hounsfield unit values among lung levels, between the sexes at full inspiration, and between age groups at full expiration. This study shows that the lower limits of lung attenuation are influenced by lung fields, sex, and, on expiration, age. [ABSTRACT FROM AUTHOR]

Computed tomography (CT) is traditionally used for evaluation and staging of gallbladder carcinoma (GC). However, in the subgroup of patients with obstructive jaundice, magnetic resonance cholangiography (MRC) is generally required to assess the level of biliary obstruction. The present study was undertaken to evaluate the diagnostic potential of three-dimensional helical CT cholangiography (3-D CTC) with minimum intensity projection (minIP), to determine the presence and level of biliary obstruction.Twenty-five consecutive patients with proven GC, presenting with clinical and biochemical features of obstructive jaundice, over a 1-year period were included in the study. Dual phase helical CT data was obtained in the arterial and venous phases, respectively, after intravenous contrast injection using a pressure injector. Axial CT data (both arterial and venous phase) was studied for staging and resectability of tumor. Three-dimensional helical CT cholangiography using minIP obtained from the venous phase data set, was used to assess the level of biliary obstruction and isolation of hepatic segmental ducts. Three-dimensional helical CT cholangiography findings were compared with MRC and percutaneous transhepatic cholangiography (PTC) (gold standard). None of the patients were operated on as they were all considered inoperable on axial CT images due to extensive local disease or distant metastasis.In all patients, 3-D CTC demonstrated dilated intrahepatic ducts up to tertiary branch level. The 3-D CTC correctly diagnosed the level of biliary obstruction and demonstrated isolated segmental ducts in all patients and correlated well in all cases with MRC and PTC findings in this regard. However, the 3-D CTC did not add any additional information over the axial source images.Three-dimensional helical CT cholangiography with minIP can correctly determine the level of biliary obstruction in patients with GC and may be a strong competitor with MRC, because it gives equivalent information with regard to the level of ductal obstruction even while being a part of an overall comprehensive CT staging study. Even though 3-D CTC did not provide additional information on top of the source images, the referring physicians found them very useful for conceptualization of the 3-D biliary anatomy. [ABSTRACT FROM AUTHOR]

Abstract Background To evaluate the accuracy of the combined maximum and minimum intensity projection-based internal target volume (ITV) delineation in 4-dimensional (4D) CT scans for liver malignancies. Methods 4D CT with synchronized IV contrast data were acquired from 15 liver cancer patients (4 hepatocellular carcinomas; 11 hepatic metastases). We used five approaches to determine ITVs: (1). ITVAllPhases: contouring gross tumor volume (GTV) on each of 10 respiratory phases of 4D CT data set and combining these GTVs; (2). ITV2Phase: contouring GTV on CT of the peak inhale phase (0% phase) and the peak exhale phase (50%) and then combining the two; (3). ITVMIP: contouring GTV on MIP with modifications based on physician's visual verification of contours in each respiratory phase; (4). ITVMinIP: contouring GTV on MinIP with modification by physician; (5). ITV2M: combining ITVMIP and ITVMinIP. ITVAllPhases was taken as the reference ITV, and the metrics used for comparison were: matching index (MI), under- and over-estimated volume (Vunder and Vover). Results 4D CT images were successfully acquired from 15 patients and tumor margins were clearly discernable in all patients. There were 9 cases of low density and 6, mixed on CT images. After comparisons of metrics, the tool of ITV2M was the most appropriate to contour ITV for liver malignancies with the highest MI of 0.93 ± 0.04 and the lowest proportion of Vunder (0.07 ± 0.04). Moreover, tumor volume, target motion three-dimensionally and ratio of tumor vertical diameter over tumor motion magnitude in cranio-caudal direction did not significantly influence the values of MI and proportion of Vunder. Conclusion The tool of ITV2M is recommended as a reliable method for generating ITVs from 4D CT data sets in liver cancer.

Chest physicians need to be aware about MinIP images, as these are increasingly being used for the evaluation of a wide range of lung diseases in HRCT study of lungs. MinIP images highlight the areas with reduced CT attenuation in the lung parenchyma. This allows prompt and early diagnosis of cystic lung diseases or airway, vascular or parenchymal disorders, which manifest with hypoattenuation, mosaic attenuation or air trapping. MiniP images are therefore useful for accurate pre-operative planning and disease monitoring. [ABSTRACT FROM AUTHOR]

OBJECTIVE. The purpose of this study was to investigate the effect of slab thickness on the detection of pulmonary nodules by use of maximum-intensity-projection (MIP) and minimum-intensity-projection (MinIP) to process CT images. MATERIALS AND METHODS. Chest CT data of 221 patients with pulmonary nodules were retrospectively analyzed. Nodules were categorized into two groups according to density: solid nodules (SNs) and subsolid nodules (SSNs). Pulmonary nodules were independently evaluated by two radiologists using axial CT images with 1-mm and 5-mm section thickness and MIP and MinIP images. MIP images for SN detection and MinIP images for SSN detection were separately reconstructed with four (5, 10, 15, 20 mm) and three (3, 8, 15 mm) slab thicknesses. The numbers and locations of detected nodules were recorded, and interobserver agreement was assessed. For each reader, the differences in nodule detection rates were evaluated in different series of images. RESULTS. Among the different series of images, interobserver agreements for detecting nodules were all good to excellent (κ ≥ 0.687). For total SNs and SNs with a diameter < 5 mm, detection rates on 10-mm MIP images were significantly higher than in other series of images (reader 1, 84.5% and 83.8%; reader 2, 83.6% and 82.2%). For total SSNs and SSNs < 5 mm, detection rates on 3-mm MinIP images were significantly higher than those in other series of images, except for 1-mm (reader 1, 93.3% and 78.6%; reader 2, 95.0% and 81.0%). CONCLUSION. Ten-millimeter MIP images are extremely efficient for detecting SNs. Three-millimeter MinIP images are more useful for visualizing SSNs, the efficiency being comparable to that achieved by use of 1-mm axial images.

Background and Purpose: The susceptibility-weighted imaging form of brain MRI using minimum intensity projection (mIP) is useful for assessing traumatic brain injuries because it readily reveals deoxyhemoglobin or paramagnetic compounds. We investigated the efficacy of using this methodology in nontraumatic patients., Methods: We retrospectively analyzed the asymmetric mIP findings in nontraumatic patients. Asymmetric mIP images were first verified visually and then using ImageJ software. We enrolled patients with a difference of >5% between hemispheres in ImageJ analysis. All patients underwent detailed history-taking and EEG, and asymmetric mIP findings were compared., Results: The visual analysis identified 54 pediatric patients (37 males and 17 females) with asymmetric mIP findings. Ten patients were excluded because they did not meet the ImageJ verification criteria. The 44 patients with asymmetry comprised 36 with epilepsy, 6 with headache, and 2 with cerebral infarction. Thirty-one of the 36 epileptic patients showed definite partial seizure activities in semiology, while the remaining patients did not demonstrate a history of partial seizure manifestations. The MRI findings were normal in all patients except for five with periventricular leukomalacia unrelated to seizure symptoms. There was agreement between mIP images and semiology in 29 (93.5%) of the 31 epileptic patients with focal signs, while the other 2 demonstrated discordance. Twenty (64.5%) of the 31 patients showed consistent EEG abnormalities., Conclusions: Our data suggest that asymmetric mIP findings are an excellent lateralizing indicator in pediatric patients with partial epilepsy., Competing Interests: The authors have no potential conflicts of interest to disclose., (Copyright © 2019 Korean Neurological Association.)

We present a case of a 10-month-old girl baby with pulmonary artery sling and bridging bronchus demonstrated using multidetector computed tomography with a three-dimensional volume-rendering display and minimum intensity projections. To the best of our knowledge, this method has been helpful not only in the diagnosis and surgical planning for this rare abnormality but also in the evaluation of prognosis. After pulmonary artery reimplantation, the patient was well and discharged.