Vascular Steal Phenomenon in Lower Limb due to Reactive Hyperemia in Contralateral Limb: A Case Series and an Explanation of a Rare Phenomenon Using Continuity Equation.

In this series of three cases, we describe the vascular steal phenomenon in an otherwise normal lower limb secondary to hyperemia in the contralateral lower limb. In each of the cases, post-inflammatory hyperemia in the involved lower limb was associated with a significant reduction in blood flow in the contralateral normal lower limb. We attempt to explain the imaging findings in these three cases using the equation of continuity in fluid dynamics. To the best of our knowledge, a description of such kind is unavailable in the published literature.

Pseudomyxoma peritonei leading to "jelly belly" abdomen: a case report and review of the literature.

BACKGROUND: Pseudomyxoma peritonei is an infrequent condition with a global annual incidence of only one to two cases per million people. Mucinous neoplasms, widespread intraperitoneal implants, and mucinous ascites characterize it. Currently, most clinicians misdiagnose this condition, which leads to delayed management. CASE PRESENTATION: A 44-year-old North Indian female presented with a 1.5-month history of an abdominal lump. Physical examination revealed a sizeable abdominopelvic mass at 36 weeks. Contrast-enhanced computed tomography showed a massive multiloculated right ovarian cystic mass measuring 28 × 23 × 13 cm with mild ascites and elevated carcinoembryonic antigen levels (113.75 ng/ml). A provisional diagnosis of ovarian mucinous neoplasm was made, for which the patient underwent laparotomy. Intraoperatively, there were gross mucinous ascites, along with a large, circumscribed, ruptured right ovarian tumor filled with gelatinous material. The appendicular lump was also filled with mucinous material along with the omentum, ascending colon, right lateral aspect of the rectum, splenic surface, and small bowel mesentery. Cytoreductive surgery was performed along with an oncosurgeon, including total abdominal hysterectomy with bilateral salpingoophorectomy, omentectomy, right hemicolectomy, lower anterior resection, ileo-transverse stapled anastomosis with proximal ileal loop diversion stoma, excision of multiple peritoneal gelatinous implants, and peritoneal lavage. Histopathology and immunohistochemistry confirmed the presence of intestinal-type mucinous carcinoma. Postoperatively, the patient was given six cycles of chemotherapy. She tolerated it without any specific morbidity and had an uneventful recovery. Postoperative follow-up at 15 months revealed normal tumor marker levels and abdominal computed tomography findings and no signs suggestive of local recurrence or distal metastases. CONCLUSIONS: Pseudomyxoma peritonei is a rare disease that is frequently misdiagnosed in the preoperative phase. Therefore, radiologists and clinicians should maintain a high index of suspicion for accurate diagnosis and multidisciplinary management.

Exploring the intersection of tuberous sclerosis and precocious puberty unveiled by hematocolpos.

We present the case of a 6-year-old girl who initially presented with acute pelvic pain, ultimately diagnosed with imperforate hymen leading to hematocolpos. Further investigation revealed additional clinical features including academic struggles, mood swings, and cutaneous findings, prompting consideration of a neurocutaneous syndrome. Magnetic Resonance Imaging (MRI) revealed features consistent with tuberous sclerosis complex (TSC), including radial migration lines in the subcortical white matter and an incidental arachnoid cyst. Notably, this case exhibited a unique presentation with absence of typical TSC findings such as subependymal nodules or cortical tubers. Additionally, precocious puberty, rarely associated with TSC, was observed, suggesting a potential link between hypothalamic lesions and hormonal imbalance. This case underscores the importance of comprehensive evaluation in pediatric patients presenting with seemingly unrelated symptoms, as it may unveil underlying conditions necessitating tailored management strategies.

Clinical Spectrum of Ophthalmic Manifestations in Myelin Oligodendrocyte Glycoprotein-Associated Disease (MOGAD): A Comprehensive Case Report.

PURPOSE: To describe diverse ocular manifestations in a patient with Myelin oligodendrocyte glycoprotein-associated disease (MOGAD). METHODS: A 15-year-old Indian male had severe loss of vision in one eye, followed by a recurrent attack of optic neuritis in the fellow eye a few weeks later. He had a history of vision loss, speech disturbances, altered sensorium and was a confirmed case of Myelin oligodendrocyte glycoprotein-associated disease (MOGAD). Apart from optic neuritis, other rare ophthalmic associations, namely, macular neuroretinopathy, retinal haemorrhages, severe optic nerve head edema, peri neuritis, and orbital enhancement on magnetic resonance imaging (MRI) were noted. RESULTS: He responded dramatically to treatment with intravenous pulse steroids and relapses were controlled with long-term immunomodulation therapy. CONCLUSION: This case report reiterates the need for early treatment with pulse steroids in MOGAD and depicts the heterogeneous involvement of various ocular structures in the disease.

Neuroimaging features in Wolfram syndrome type 1.

Wolfram syndrome type 1 is a rare autosomal recessive genetic disorder which is characterized by the co-existence of diabetes insipidus, diabetes mellitus, optic atrophy, and deafness, and hence is also referred to as the acronym DIDMOAD. In this neuroimage, the typical neuroimaging features of a genetically confirmed case of Wolfram syndrome type 1 are presented. The presence of left-sided vestibulocochlear dysplasia is a novel finding in our case which has not been reported previously.

Neuroimaging Genomics a Predictor of Major Depressive Disorder (MDD).

Depression is a complex psychiatric disorder influenced by various genetic and environmental factors. Strong evidence has established the contribution of genetic factors in depression through twin studies and the heritability rate for depression has been reported to be 37%. Genetic studies have identified genetic variations associated with an increased risk of developing depression. Imaging genetics is an integrated approach where imaging measures are combined with genetic information to explore how specific genetic variants contribute to brain abnormalities. Neuroimaging studies allow us to examine both structural and functional abnormalities in individuals with depression. This review has been designed to study the correlation of the significant genetic variants with different regions of neural activity, connectivity, and structural alteration in the brain as detected by imaging techniques to understand the scope of biomarkers in depression. This might help in developing novel therapeutic interventions targeting specific genetic pathways or brain circuits and the underlying pathophysiology of depression based on this integrated approach can be established at length.

Evaluation of the Diagnostic Performance of F18-Fluorodeoxyglucose-Positron Emission Tomography, Dynamic Susceptibility Contrast Perfusion, and Apparent Diffusion Coefficient in Differentiation between Recurrence of a High-grade Glioma and Radiation Necrosis.

Background: Differentiation between recurrence of brain tumor and radiation necrosis remains a challenge in current neuro-oncology practice despite recent advances in both radiological and nuclear medicine techniques. Purpose: The purpose of this study was to compare the diagnostic performance of dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI), apparent diffusion coefficient (ADC) derived from diffusion-weighted imaging, and F18-fluorodeoxyglucose-positron emission tomography (F18-FDG-PET) in the differentiation between the recurrence of a high-grade glioma and radiation necrosis. Materials and Methods: Patients with a diagnosis of high-grade glioma (WHO Grades III and IV) who had undergone surgical resection of the tumor followed by radiotherapy with or without chemotherapy were included in the study. DSC perfusion, diffusion-weighted MRI, and PET scan were acquired on a hybrid PET/MRI scanner. For each lesion, early and delayed tumor-to-brain ratio (TBR), early and delayed maximum standardized uptake value (SUVmax), normalized ADC ratio, and normalized relative cerebral blood volume (rCBV) ratio were calculated and the pattern of lesional enhancement was noted. The diagnosis was finalized with either histopathological examination or the characteristics on follow-up imaging. The statistical analysis using the receiver operator characteristic curves was done to determine the diagnostic performance of DSC perfusion, 18-F FDG-PET, and ADC in differentiation between tumor recurrence and radiation necrosis. Results: Fifty patients were included in the final analysis, 32 of them being men (64%). A cutoff value of early TBR >0.8 (sensitivity of 100% and specificity of 80%), delayed TBR >0.93 (sensitivity of 92.3% and specificity of 80%), early SUVmax >10.2 (sensitivity of 76.9% and specificity of 80%), delayed SUVmax >13.2 (sensitivity of 61.54% and specificity of 100%), normalized rCBV ratio >1.21 (sensitivity of 100% and specificity of 60%), normalized ADC ratio >1.66 (sensitivity of 38.5% and specificity of 80%), and Grade 3 enhancement (sensitivity of 100% and specificity of 60%) were found to differentiate recurrence from radiation necrosis. Early TBR had the highest accuracy (94.44%), while ADC ratio had the lowest accuracy (50%). A combination of early TBR (cutoff value of 0.8), late TBR (cutoff value of 0.93), and rCBV ratio (cutoff value of 1.21) showed a sensitivity of 100%, specificity of 92.3%, positive predictive value of 88.9%, negative predictive value of 93.7%, and an accuracy of 96.6% in discrimination between radiation necrosis and recurrence of tumor. Conclusion: F18-FDG-PET and DSC perfusion can reliably differentiate tumor recurrence from radiation necrosis, with early TBR showing the highest accuracy. ADC demonstrates a low sensitivity, specificity, and accuracy in differentiating radiation necrosis from recurrence. A combination of early TBR, delayed TBR, and rCBV may be more useful in discrimination between radiation necrosis and recurrence of glioma, with this combination showing a better diagnostic performance than individual parameters or any other combination of parameters.

Intraluminal arterial transit artifact as a predictor of intracranial large artery stenosis on 3D time of flight MR angiography: Expanding the application of arterial spin labeling MRI in ischemic stroke.

Objectives: The objective of this study was to evaluate the diagnostic value of "intraluminal arterial transit artifact" in the prediction of intracranial large artery stenosis and to determine if this finding is predictive of ischemic stroke in the territory of the involved artery. Material and Methods: The presence of arterial transit artifact (ATA) within the lumen of an intracranial large vessel was noted on three-dimensional time of flight (3D-TOF) magnetic resonance angiography (MRA) (ATA group). The patients with stenosis but with no ATA (no-ATA group), patients with total occlusion (total occlusion group), and patients with no stenosis/occlusion (normal group) were included in the analysis. Results: There were four groups of patients included in the final analysis, the ATA group (n = 22), the no-ATA group (n = 23), the normal group (n = 25), and the total occlusion group (n = 9). Among patients with any demonstrable stenosis (n = 45), the presence of ATA within the stenotic segment was predictive of stenosis of ≥56% (Sensitivity of 100% [85.2-100, 95% CI], specificity of 100% [86.4-100, 95% CI]), with area under curve of 1.0 (0.92-.0, 95% CI). The presence of intra-arterial ATA signal was significantly associated with ischemic stroke as compared with the no-ATA group (86.36% vs. 26.08%, P = 0.0003). Intraluminal ATA was found to be an independent predictor of infarction in the territory of the involved artery. Conclusion: Intraluminal ATA is predictive of stenosis of at least 56% in the involved artery on 3D-TOF MRA. Intraluminal ATA sign may be an independent predictor of infarction in the territory of the involved artery.

Resting-State Functional MRI/PET Profile as a Potential Alternative to Tri-Modality EEG-MR/PET Imaging: An Exploratory Study in Drug-Refractory Epilepsy.

Objective The study explores whether the epileptic networks associate with predetermined seizure onset zone (SOZ) identified from other modalities such as electroencephalogram/video electroencephalogram/structural MRI (EEG/VEEG/sMRI) and with the degree of resting-state functional MRI/positron emission tomography (RS-fMRI/PET) coupling. Here, we have analyzed the subgroup of patients who reported having a seizure on the day of scan as postictal cases and compared the findings with interictal cases (seizure-free interval). Methods We performed independent component analysis (ICA) on RS-fMRI and 20 ICA were hand-labeled as large scale, noise, downstream, and epilepsy networks (Epinets) based on their profile in spatial, time series, and power spectrum domains. We had a total of 43 cases, with 4 cases in the postictal group (100%). Of 39 cases, 14 cases did not yield any Epinet and 25 cases (61%) were analyzed for the final study. The analysis was done patient-wise and correlated with predetermined SOZ. Results The yield of finding Epinets on RS-fMRI is more during the postictal period than in the interictal period, although PET and RS-fMRI spatial, time series, and power spectral patterns were similar in both these subgroups. Overlaps between large-scale and downstream networks were noted, indicating that epilepsy propagation can involve large-scale cognition networks. Lateralization to SOZ was noted as blood oxygen level-dependent activation and correlated with sMRI/PET findings. Postoperative surgical failure cases showed residual Epinet profile. Conclusion RS-fMRI may be a viable option for trimodality imaging to obtain simultaneous physiological information at the functional network and metabolic level.

A case report of successful percutaneous aspiration, injection, and re-aspiration (PAIR) technique for treatment of retrovesical pelvic hydatid cyst.

Pelvis is a rare location for occurrence of hydatid cyst with only a few cases reported in the literature. All the previous reports of pelvic hydatid cysts were managed with either surgical exploration and excision or laparoscopic intervention. In this case report, we describe the successful treatment of a large pelvic hydatid cyst located in the retrovesical space using the percutaneous aspiration, injection, and respiration (PAIR) technique. To the best of our knowledge, this is the first successful demonstration of the PAIR technique in the treatment of retrovesical pelvic hydatid cyst. Percutaneous treatment of hydatid cyst in this case yielded desirable reduction in the size of the cyst with subsequent involution and relief of the pressure symptoms on the urinary bladder and obviated the need for a surgical procedure.

Cerebrofacial venous metameric syndrome type 2+3: face is the index of brain.

We describe a rare case of a 20-year-old man who presented with an extensive facial and orbital venous malformation associated with multiple intracranial venous malformations. The co-existence of cerebrofacial venous malformations points towards a common final pathway in development of these malformations. Our findings are consistent with few previous similar case descriptions. In addition, we describe some novel observations which, to the best of our knowledge, have not been described in the literature. This case reinforces the concept of metameric and segmental distribution of cerebrofacial vasculature, and the aberrations thereof leading to the metameric venous malformations, as proposed by Lasjaunias et al.

CURVED MULTIFORMAT IMAGING OF STRUCTURAL MRI AS A BIOMARKER FOR PROFILING OF VARIOUS DEMENTIA - AN ALGORITHMIC APPROACH WITH MR/PET.

BACKGROUND: Dementia is one of the most common clinical entities for which neuroimaging is done for diagnosis and characterization of the sub-types. OBJECTIVE: Advanced neuroimaging modalities like MR-PET have added to the armamentarium of the neuroradiologists for the diagnosis of specific types of dementia syndromes. However, advanced molecular imaging is expensive and is not widely available particularly in underdeveloped countries. Structural imaging with MRI in addition to the clinical work up remains the most useful approach to the diagnosis of dementia in our setup. MATERIAL AND METHODS: We describe a simple technique of curved multiplanar reconstruction of brain images with the use of a simple reconstruction software which can help in recognition of pattern of atrophy in dementias and thus improve the diagnostic accuracy of structural MRI. RESULTS: Using this approach of pattern recognition, we suggest a simplified algorithm for diagnosis of sub-types of dementia. CONCLUSIONS: In our study, we applied this technique for demonstration of pattern of atrophy which correlated with metabolic changes on PET in a variety of dementia cases using simultaneous MR-PET imaging and may act as a low cost and reliable biomarker to profile dementia subtypes. To the best of our knowledge this is the first study to show the utility of curved multiplanar reconstruction in dementias.