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FTLD (Frontotemporal lobar degeneration) is a clinically and pathologically heterogeneous group of degenerative disorders, characterized by predominantly asymmetric degeneration of frontal and temporal lobes with selective neuronal loss and gliosis. The disease presents with variable degrees of impairment in behavior, language, executive control, and motor symptoms with progressive loss of cognition. On the basis of presenting clinical symptoms, FTLD is further divided into behavioral variant, nonfluent/agrammatic variant primary progressive aphasia (PPA), semantic variant PPA, logopenic variant PPA, progressive supranuclear palsy, and corticobasal ganglionic degeneration. Here we illustrate the utility of FDG PET with statistical parametric analysis for evaluation of these patients.

There is a plethora of Artificial Intelligence (AI) tools that are being developed around the world aiming at either speeding up or improving the accuracy of radiologists. It is essential for radiologists to work with the developers of such algorithms to determine true clinical utility and risks associated with these algorithms. We present a framework, called an Algorithmic Audit, for working with the developers of such algorithms to test and improve the performance of the algorithms. The framework includes concepts of true independent validation on data that the algorithm has not seen before, curating datasets for such testing, deep examination of false positives and false negatives (to examine implications of such errors) and real-world deployment and testing of algorithms.

PURPOSE To study the imaging patterns of Posterior cortical atrophy (PCA) and Dementia with Lewy bodies (DLB) on fluoro-deoxyglucose positron emission tomography computed tomography ([F]FDG PET/CT), identify areas of overlap and differences and to develop a prediction model to assist in diagnosis using univariate and multivariate analysis. METHODS A retrospective analysis of 72 patients clinically suspected of having posterior dementia was done. All patients underwent [FF]FDG PET/CT of the brain and dopamine transporter imaging with [[Tc]TRODAT-1 SPECT scan on separate days. The patients were divided into PCA with normal TRODAT uptake (n=34) and DLB with abnormal TRODAT uptake (n=38). The FDG PET/CT uptake patterns were recorded and areas of significant hypometabolism by z score analysis were considered as abnormal. Receiver operator characteristics (ROC) curve analysis was used to determine cutoff z scores and binary logistic regression analysis was used to determine the Odds ratio of being in the predicted groups. RESULTS Significantly hypometabolism was found in parieto-temporo-occipital association cortices and cingulate cortices in PCA patients. DLB patients showed significantly reduced uptake in the visual cortex. No significant difference was found between z score of occipital association cortex which showed hypometabolism in both groups. The cut-off z-score values derived from the ROC curve analysis were as follows- parietal association (cut-off-3, sensitivity-65.6%, specificity - 68.7%), temporal association (cut-off-2, sensitivity-78%, specificity-75%) and posterior cingulate (cut-off-0.5, sensitivity-93.7%, specificity-40.6%), their respective Odds ratio (with 95% confidence interval) for being in the PCA group as derived from univariate logistic regression were 3.66 (1.30-10.32), 10.71 (3.36-34.13) and 7.85 (1.57-39.17). The cut-off z score of primary visual cortex as derived from ROC curve was zero with sensitivity of 87.5%, specificity of 71.9%, and the Odds ratio for being the in the DLB group was 24.7 with 95% confidence interval of 5.99-101.85. CONCLUSION [F]FDG PET may be useful as a non-invasive diagnostic modality in differentiating the two posterior cortical dementias, despite significant overlap. Primary visual cortical hypometabolism can serve as an independent diagnostic marker for DLB, even in the absence of TRODAT imaging.

Multidimensional diffusion MRI (MDD MRI) is a novel diffusion technique that uses advanced gradient waveforms for microstructural tissue characterization to provide information about average rate, anisotropy and orientation of the diffusion and to disentangle the signal fraction from specific cell types i.e., elongated cells, isotropic cells and free water.To review the diagnostic potential of MDD MRI in the clinical setting for microstructural tissue characterization in patients with neurological disorders to aid in patient care and treatment.A scoping review on the clinical applications of MDD MRI was conducted from original articles published in PubMed and Scopus from 2015 to 2021 using the keywords "Multidimensional diffusion MRI" OR "diffusion tensor distribution" OR "Tensor-Valued Diffusion" OR "b-tensor encoding" OR "microscopic diffusion anisotropy" OR "microscopic anisotropy" OR "microscopic fractional anisotropy" OR "double diffusion encoding" OR "triple diffusion encoding" OR "double pulsed field gradients" OR "double wave vector" OR "correlation tensor imaging" AND "brain" OR "axons".Initially 145 articles were screened and after applying inclusion and exclusion criteria, nine articles were included in the final analysis. In most of these studies, microscopic diffusion anisotropy within the lesion showed deviation from the normal-appearing tissue.Multidimensional diffusion MRI can provide better quantification and visualization of tissue microstructure than conventional diffusion MRI and can be used in the clinical setting for diagnosis of neurological disorders.

Aims To explore the impact of incorporating a faster cardiac magnetic resonance (CMR) imaging protocol in a low–middle-income country (LMIC) and using the result to guide chelation in transfusion-dependent patients. Methods and results A prospective UK–India collaborative cohort study was conducted in two cities in India. Two visits 13 months apart included clinical assessment and chelation therapy recommendations based on rapid CMR results. Participants were recruited by the local patient advocate charity, who organized the patient medical camps. The average scanning time was 11.3 ± 2.5 min at the baseline and 9.8 ± 2.4 min (P Conclusion For thalassaemia patients in an LMIC, a simplified CMR protocol linked to therapeutic recommendation via the patient camp model led to enhanced chelation therapy and a reduction in cardiac iron in 1 year.

To assess osteotome-mediated sinus floor elevation (OMSFE) with simultaneous implant placement using an in situ hardening biphasic calcium phosphate (BCP) compared to xenograft as a control.Patient in need for sinus floor augmentation in one or both sinuses were selected for this randomised controlled clinical trial. Sites presenting a residual sinus floor height of 3-6 mm and eligible for OMSFE were randomly assigned to receive either BCP (test) or xenograft particles (control). CBCT scans were performed before and at the time of implant loading (180 days). The difference in sinus floor height gain between the two groups was set as the primary endpoint parameter for equivalence testing. The implant insertion torque (ITV) was recorded and Implant stability quotients (ISQ) was assessed upon implant placement, abutment connection (160 days) and implant loading (180 days).A total of 54 sinus lifts were performed in 42 patients including 12 bilateral cases. Four implants failed (two in each group) and a total of six patients were lost to follow-up. Statistical analysis of sinus floor height revealed no significant differences (p0.05) between groups at baseline nor at 180 days after augmentation. There was no statistical difference in sinus floor height gain between the two groups as supported by the 90% confidence intervals of the difference between groups. Good primary implant stability was confirmed in both treatment groups by ITV and ISQ measurements.Within the limits of this study, it can be concluded that OMSFE using in situ hardening BCP particles results in equivalent sinus floor height gain than using xenograft particles but offers an easier application.

Context Excess hepatic and pancreatic fat may contribute to hyperglycemia. Objective The objective of this study was to examine the effect of dapagliflozin (an SGLT2 inhibitor) on anthropometric profile, liver, and pancreatic fat in patients with type 2 diabetes mellitus (T2DM). Methods This is an observational interventional paired study design without a control group. Patients (n = 30) were given dapagliflozin 10 mg/day (on top of stable dose of metformin and/or sulfonylureas) for 120 days. Changes in anthropometry (circumferences and skinfold thickness), surrogate markers of insulin resistance, body composition, liver, and pancreatic fat (as measured by magnetic resonance imaging (MRI)-derived proton density fat fraction [FF]) were evaluated. Results After 120 days of treatment with dapagliflozin, a statistically significant reduction in weight, body mass index (BMI), body fat, circumferences, and all skinfold thickness was seen. A statistically significant reduction in blood glucose, glycated hemoglobin A1c, hepatic transaminases, fasting insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and postprandial C-peptide was noted, while HOMA-β, postprandial insulin sensitivity, and fasting adiponectin were statistically significantly increased. There was no change in lean body mass. Compared to baseline there was a statistically significant decrease in mean liver FF (from 15.2% to 10.1%, P Conclusion Dapagliflozin, after 120 days of use, reduced pancreatic and liver fat and increased insulin sensitivity in Asian Indian patients with T2DM.

Purpose The aims of this study were to evaluate Tc-TRODAT-1 SPECT imaging patterns and to assess their correlation with disease severity in clinically diagnosed patients of Parkinson disease (PD). Methods The study included 241 patients with clinically diagnosed idiopathic Parkinson disease who underwent Tc-TRODAT-1 SPECT/CT scan. Binding ratios were calculated for each striatum, caudate, and putamen individually, by drawing region of interest. Occipital cortex region of interest was taken for background correction. Correlation of binding ratio with increasing clinical stage was derived, as described by modified Hoehn and Yahr scale. Results Median binding ratio was least in the contralateral putamen for all stages of modified Hoehn and Yahr. A statistically significant negative correlation was found between increasing disease severity and binding ratio in all subregions of striatum. Patients were clinically categorized into postural instability and gait disorder group and tremor-dominant PD group. No significant asymmetry was found between the left and right striatum in patients belonging to postural instability and gait disorder group and in those with bilateral tremors without lateralization. Conclusions Tc-TRODAT-1 SPECT is useful in early detection and in assessing disease severity of PD. A significant asymmetry with the contralateral side being affected more than the ipsilateral side can be attributed to tremor-dominant patients. The binding ratio of the ipsilateral striatum may serve useful as a marker of remaining functional dopaminergic neuronal reserve in the striatum.

A 57-year-old man, on octreotide treatment for metastatic neuroendocrine tumor pancreas, was referred for whole-body Ga-DOTANOC PET/CT scan to evaluate treatment response. PET/CT scan revealed DOTANOC-avid lesion in the head of the pancreas with multiple tracer-avid soft tissue lesions in the liver, bilateral adrenal glands, and periportal lymph nodes. In addition, diffuse intense DOTANOC-avid mural thickening with intraluminal polypoidal mass formation was noted within the stomach causing significant luminal compromise, histopathological examination of which turned out be hypertrophic hypersecretory gastropathy. This case highlights the possibility of overexpression of somatostatin receptors in gastric hypertrophy, which has been little explored in literature.

We report a case of 34-year-old woman presenting with complaints of abnormal posturing of hand and tonic-clonic seizures of few days' duration, which soon progressed to psychotic episodes and injuries secondary to fall/abnormal movements. She underwent F-FDG PET for a suspicion of encephalitis, which revealed increased FDG uptake in the bilateral parietotemporal lobes (right more than left), anterior cingulate cortex, bilateral basal ganglia, thalami, and cerebellum. This atypical pattern did not conform to any known pattern of encephalitis, which was later attributed to the presence of both anti-NMDAr and anti-GAD antibodies in blood and cerebrospinal fluid.

Autoimmune encephalitis is a diverse group of neuropsychiatric disorders, which are difficult to diagnose clinically. The disorder presents acutely or subacutely with alteration of consciousness, cognitive decline, seizures, and abnormal movements. Autoantibodies are directed against intracellular antigens or extracellular domains of cell surface proteins, critical for neuronal excitability. F-FDG PET/CT has been used to diagnose the metabolic derangement in the brain due to various antibodies. Here we describe a case where acute and subacute phase of disease was visualized on serial F-FDG PET/CT.

A 63-year-old man, recently diagnosed with carcinoma of the prostate (Gleason's score 4+4), with serum prostate-specific antigen 189.2 ng/mL, underwent Ga PSMA PET/CT scan for pretreatment staging. The study revealed abnormal tracer uptake in the prostatic bed region, the pelvic, abdominal, and mediastinal lymph nodes and diffuse metastases to the bilateral lungs. The lung metastasis was proved to be metastatic adenocarcinoma from analysis of bronchoalveolar lavage.

Rationale and Objectives To explain predictions of a deep residual convolutional network for characterization of lung nodule by analyzing heat maps. Materials and Methods A 20-layer deep residual CNN was trained on 1245 Chest CTs from National Lung Screening Trial (NLST) trial to predict the malignancy risk of a nodule. We used occlusion to systematically block regions of a nodule and map drops in malignancy risk score to generate clinical attribution heatmaps on 103 nodules from Lung Image Database Consortium image collection and Image Database Resource Initiative (LIDC-IDRI) dataset, which were analyzed by a thoracic radiologist. The features were described as heat inside nodule -bright areas inside nodule, peripheral heat continuous/interrupted bright areas along nodule contours, heat in adjacent plane -brightness in scan planes juxtaposed with the nodule, satellite heat - a smaller bright spot in proximity to nodule in the same scan plane, heat map larger than nodule bright areas corresponding to the shape of the nodule seen outside the nodule margins and heat in calcification. Results These six features were assigned binary values. This feature vector was fedinto a standard J48 decision tree with 10-fold cross-validation, which gave an 85 % weighted classification accuracy with a 77.8% True Positive (TP) rate, 8% False Positive (FP) rate for benign cases and 91.8% TP and 22.2% FP rates for malignant cases. Heat Inside nodule was more frequently observed in nodules classified as malignant whereas peripheral heat, heat in adjacent plane, and satellite heat were more commonly seen in nodules classified as benign. Conclusion We discuss the potential ability of a radiologist to visually parse the deep learning algorithm generated “heat map” to identify features aiding classification.

We aimed to compare C-peptide levelsmeasures of insulin resistance in non-leannon-obese Asian Indian patients with type 2 diabetes (T2DM) vs. non-lean, non-diabetic controls and to correlate with anthropometric measures, volumes of abdominal adipose tissue depots, pancreas,liver span.Non-lean, non-obese (BMI19 and 25 kg/mIn cases, the mean values of HbA1c, fasting and post prandial insulin and C-peptide levels, and 3 measures of insulin resistance were significantly higher than controls, but not for HOMA-B. Higher fasting C-peptide levels correlated significantly with HOMA-IR (r = 0.42, p 0.001), Fasting Insulin Resistance Index (r = 0.42, p 0.001), Bennett's Index (r = 0.38, p 0.05), and volumes of SCAT and IAAT only in cases. The independent predictors of higher fasting C-peptide level were IAAT volume (β = 0.057; p = 0.002), liver span (β = 0.057, p = 0.005) and fasting insulin levels (β = 0.35, p = 0.02).Higher fasting and post-prandial C-peptide levels and surrogate measures of insulin resistance in non-obese Asian Indian patients with T2DM are independently associated with IAAT volume and liver span.

We present the case of a 53-year-old man with left hydroureteronephrosis who underwent Tc-DTPA renography for functional assessment of bilateral kidneys. Tc-DTPA renography of the patient showed diffusely increased extrarenal Tc-DTPA uptake in the visualized lumbosacral vertebrae and in the pelvic bones, on the blood flow and functional phase of the renography, which was suggestive of disseminated skeletal disease. Subsequent MRI lumbosacral spine and F-FDG PET/CT revealed extensive skeletal metastases corresponding to the increased extrarenal Tc-DTPA uptake in the lumbosacral vertebrae and the pelvic bones from primary left lung mitotic lesion.

We aimed to correlate plasma glucagon levels with anthropometric measures and abdominal adipose tissue depots. Nonobese males (n=81; BMI 2) with T2DM of less than one-year duration and nonobese males without diabetes (n=30) were evaluated for the following: anthropometry (BMI, waist circumference, W-HR, and truncal skinfolds), whole-body DEXA (for body fat and fat-free mass), and MRI scan (for volumes of subcutaneous abdominal adipose tissue (SCAT) including superficial and deep, intra-abdominal visceral adipose tissue (including intraperitoneal adipose tissue (IPAT), retroperitoneal adipose tissue, liver span and fatty liver, and pancreatic volume)). Plasma glucose and glucagon, serum insulin, hepatic transaminases, and lipid profile were measured. Significantly higher levels of fasting and postprandial glucagon (p<0.001) and fasting and postprandial insulin (p<0.001) were seen in patients with T2DM. The mean values of fasting and postprandial plasma glucagon levels were higher in T2DM patients with NAFLD (n=37) as compared to T2DM patients without NAFLD (n=44). Four independent predictors were derived for fasting glucagon levels in patients with T2DM, namely, W-HR, suprailiac skinfold thickness, IPAT, and deep SCAT (p<0.05; r2=0.84). These observations in Asian Indians may have significance for diabetes therapies which impact glucagon levels.

Perinatal/congenital tuberculosis is a rare entity, even in human immunodeficiency virus (HIV) endemic populations, and is uniformly fatal if untreated. The liver and the lungs are the most commonly involved organs in this variety of tuberculosis and the spine is a rare site. We report the first case of spine tuberculosis with paravertebral abscess in a neonate who was only 3 weeks of age. The imaging studies, namely radiography, sonography, computed tomography (CT)-guided aspiration and magnetic resonance imaging (MRI), facilitated rapid diagnosis and early institution of chemotherapy. We highlight the role of imaging evaluation in the diagnostic armamentarium for tuberculosis of the newborn, as early diagnosis followed by appropriate treatment resulted in an excellent recovery in our patient.

Statement of Problem: The fracture of complete denture is a common occurrence in the field of prosthodontics. Often if all other criteria are met such as good aesthetics, occlusion, and functionality; denture repair is acceptable. Once denture fractures, we would want the joint surface strength to be as good as original. Purpose: The purpose of this study was to determine the effect of different repair surface design on the transverse strength of repaired acrylic denture resin. Materials and Methods : Sixty specimens of heat‑cured acrylic resin of dimension 65 mm × 20 mm × 2.5 mm were prepared using a special die. Transverse strength of 15 samples was calculated which serves as a control group. Three different types of joint surface contours were prepared each having 15 samples each as butt, round, and rabbet joint. Transverse strength of three joint contours was then compared with control group and also they were compared with each other and result was statistically analyzed with one‑way analysis of variance (ANOVA) and Post‑hoc ANOVA Tukey’s HSD test at 5% level of significance. Z‑test of proportion was also done for types of failures. Result: Transverse strength of original specimen was higher than that of repaired specimens. Transverse strength of round joint was higher than the butt and rabbet joint. Conclusion : Methods of repair have significant effect on strength of repaired denture. Round joint design of repair technique was far superior. Key words : Autopolymerizing resin, rabbet joint, transverse strength

Intracranial aneurysms in early childhood are rare. Mycotic aneurysms as a cause of pyrexia of unknown origin has never been reported. We present a 9-month-old immunodeficient boy who had a long history of irregular fever from neonatal period and presented to us with subarachnoid hemorrhage. Investigation revealed a basilar top aneurysm. We present the clinicoradiological profile and discuss the management strategies.

Ten patients with biopsy-proved synovial sarcoma were evaluated by magnetic resonance (MR) imaging on a 1.5-T unit. The lesions showed intermediate signal intensity on T1-weighted images and heterogeneous high signal intensity on T2-weighted images. Tumors were well-demarcated from normal tissues. Additional information included adjacent bone involvement (one case), femoral vein invasion by tumor (one case), and hemorrhage within the tumors (one case). Four patients underwent a repeat MR examination following chemotherapy. This showed a decrease in size and increase in the signal intensity of three tumors on T2-weighted images, proven to be due to necrosis in one. These changes correlated with clinical regression of disease. While MR in synovial sarcoma does not have any specific signal intensity, it proved to be useful in defining the extent of disease and in determining the response to chemotherapy.

The magnetic resonance imaging (MRI) changes in 39 patients with malignant fibrous histiocytoma (MFH) were reviewed retrospectively. Twenty-one sarcomas were in the lower extremity, five each in the upper extremity and trunk, two each in the neck and heart, and one each in the maxillary sinus, sella turcica, tongue, and spermatic cord. The examinations were performed with spin-echo sequences on a 1.5 Tesla Signa Scanner (GE, Milwaukee WI). Twenty-two tumors exhibited intermediate signal intensity on T 1 -weighted images and 23 were of high signal intensity on T 2 -weighted images. There was no significant difference in signal intensity of 12 preoperative and 13 recurrent neoplasms. Twelve of 13 patients were correctly diagnosed as having postoperative changes. The MR sensitivity and specificity for detecting a neoplasm were 96% and 83% respectively, but the signal changes were nonspecific for MFH. When compared to CT in 14 patients, MR better defined the extent of the MFH, its relationship to surrounding tissues and vessels, and best differentiated residual or recurrent disease from postoperative changes when examined at least 3 months after surgery.