26 results on '"Harsh Mahajan"'
Search Results
2. Spectrum of Frontotemporal Lobar Degeneration on 18F-FDG PET/CT Scan
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Ethel Shangne Belho, Harsh Mahajan, Vanshika Gupta, Ritu Verma, Rajeev Kumar Ranjan, and Nikhil Seniaray
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Male ,Pathology ,medicine.medical_specialty ,Degenerative Disorder ,Degeneration (medical) ,Motor symptoms ,030218 nuclear medicine & medical imaging ,Progressive supranuclear palsy ,Primary progressive aphasia ,03 medical and health sciences ,0302 clinical medicine ,Fluorodeoxyglucose F18 ,Positron Emission Tomography Computed Tomography ,mental disorders ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,business.industry ,General Medicine ,Frontotemporal lobar degeneration ,Middle Aged ,respiratory system ,medicine.disease ,nervous system diseases ,Gliosis ,030220 oncology & carcinogenesis ,Female ,Fdg pet ct ,Frontotemporal Lobar Degeneration ,medicine.symptom ,business - Abstract
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.
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- 2020
3. The Algorithmic Audit: Working with Vendors to Validate Radiology-AI Algorithms—How We Do It
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Murali Murugavel, Harsh Mahajan, Vasantha Kumar Venugopal, and Vidur Mahajan
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Computer science ,False positives and false negatives ,Audit ,030218 nuclear medicine & medical imaging ,Test (assessment) ,Radiography ,03 medical and health sciences ,0302 clinical medicine ,Artificial Intelligence ,Software deployment ,030220 oncology & carcinogenesis ,Radiologists ,Humans ,Radiology, Nuclear Medicine and imaging ,Radiology ,Algorithm ,Algorithms - Abstract
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.
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- 2020
4. Metabolic imaging patterns in posterior cortical atrophy and Lewy body dementia
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Ritu Verma, Ethel Shangne Belho, Dharmender Malik, Harsh Mahajan, Vanshika Gupta, Rajeev Kumar Ranjan, Nikhil Seniaray, and Veronique Dinand
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Lewy Body Disease ,Male ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Fluorodeoxyglucose F18 ,Positron Emission Tomography Computed Tomography ,Image Processing, Computer-Assisted ,medicine ,Humans ,Dementia ,Radiology, Nuclear Medicine and imaging ,Retrospective Studies ,Lewy body ,Receiver operating characteristic ,business.industry ,Dementia with Lewy bodies ,Brain ,Posterior cortical atrophy ,General Medicine ,Odds ratio ,Middle Aged ,medicine.disease ,Confidence interval ,030220 oncology & carcinogenesis ,Posterior cingulate ,Multivariate Analysis ,Female ,Atrophy ,Nuclear medicine ,business - Abstract
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.
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- 2019
5. Semiquantitative Interpretation Criteria for Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Large-Vessel Vasculitis: Pattern Recognition and Correlation with Polymyalgia Rheumatica
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Ritu Verma, Harsh Mahajan, Babita Drolia, Nikhil Seniaray, Dharmender Malik, Ethel Shangne Belho, and Vanshika Gupta
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030203 arthritis & rheumatology ,Reproducibility ,medicine.diagnostic_test ,business.industry ,Abdominal aorta ,large-vessel vasculitis ,medicine.disease ,polymyalgia rheumatica ,030218 nuclear medicine & medical imaging ,Polymyalgia rheumatica ,03 medical and health sciences ,0302 clinical medicine ,Erythrocyte sedimentation rate ,medicine.artery ,Large vessel vasculitis ,medicine ,Thoracic aorta ,Radiology, Nuclear Medicine and imaging ,Original Article ,Tomography ,Vasculitis ,Nuclear medicine ,business ,Fluorodeoxyglucose-positron emission tomography/computed tomography ,total vascular score - Abstract
Background: Fluorine-18-fluorodeoxyglucose (18F-FDG)-positron emission tomography/computed tomography (PET/CT) is emerging as a useful imaging modality in suspected large-vessel vasculitis (LVV), owing to its ability to accumulate at the sites of inflammation within the arterial walls. However, there remains scope for standardization of reporting criteria to ensure reproducibility. Recently, a semiquantitative scoring system called “total vascular score” (TVS) has been suggested as a method to standardize and harmonize FDG PET/CT evaluation in LVV patients. The purpose of this study was to assess the clinical utility of the proposed semiquantitative grading scale in LVV patients. Materials and Methods: Patients presenting with clinical symptoms of vasculitis, who had undergone a baseline FDG-PET/CT were evaluated. 18F-FDG uptake in the major vessels was quantified with standardized uptake values (SUVsmax) using four-point scale by three independent nuclear physicians. TVS was calculated based on the calculation of the vascular uptake values with respect to mediastinal blood pool and liver uptake and the number of vessels involved. Results: A total of 106 PET-positive patients (74 males and 32 females) were evaluated. The most frequently involved vessels were thoracic aorta >abdominal aorta >subclavian arteries with mean SUVmax values of 4.05, 3.12, and 2.70, respectively. Mean TVS was 13.18 ± 3.4 (range 03–19) among 276 involved vessels. TVS showed significant positive correlation with erythrocyte sedimentation rate (r = 0.82; P < 0.005). 18 patients showed periarticular FDG uptake, with shoulder joint being the most commonly involved joint. Conclusion: The simplified visual and semiquantitative grading scale for interpretation and reporting classification provides better objectivity in diagnosis, communication with referring clinicians, and planning in patients of LVV.
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- 2019
6. Correlation of 99mTc-TRODAT-1 SPECT Imaging Findings and Clinical Staging of Parkinson Disease
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Harsh Mahajan, Ritu Verma, Rajeev Kumar Ranjan, Dharmender Malik, Ethel Shangne Belho, and Vanshika Gupta
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Male ,medicine.medical_specialty ,Striatum ,Lateralization of brain function ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Region of interest ,Internal medicine ,Spect imaging ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Stage (cooking) ,Aged ,Aged, 80 and over ,Tomography, Emission-Computed, Single-Photon ,business.industry ,Putamen ,Dopaminergic ,Parkinson Disease ,Organotechnetium Compounds ,General Medicine ,Middle Aged ,Gait ,nervous system ,030220 oncology & carcinogenesis ,Cardiology ,Female ,Radiopharmaceuticals ,business ,Tropanes - Abstract
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.
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- 2019
7. High fasting C-peptide levels and insulin resistance in non-lean & non-obese (BMI >19 to < 25 kg/m2) Asian Indians with type 2 diabetes are independently associated with high intra-abdominal fat and liver span
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Surya P. Bhatt, Harsh Mahajan, Seema Gulati, Anoop Misra, and Shajith Anoop
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0301 basic medicine ,medicine.medical_specialty ,endocrine system diseases ,Intra-Abdominal Fat ,Endocrinology, Diabetes and Metabolism ,medicine.medical_treatment ,Liver span ,Adipose tissue ,030209 endocrinology & metabolism ,Type 2 diabetes ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Insulin resistance ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,Medicine ,business.industry ,C-peptide ,Insulin ,nutritional and metabolic diseases ,General Medicine ,medicine.disease ,030104 developmental biology ,Endocrinology ,chemistry ,business - Abstract
Background and objectives We aimed to compare C-peptide levels & measures of insulin resistance in non-lean & non-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. Methods Non-lean, non-obese (BMI >19 and Results In 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 Conclusion 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.
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- 2019
8. 'Honeycomb' pattern of gallbladder wall thickening – A forward step in early diagnosis of 'Severe Dengue Fever'
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Chander Mohan, Tapan Patel, Jitendra Parmar, Harsh Mahajan, Sandip C Shah, and Maulik Vora
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Gallbladder wall thickening ,medicine.medical_specialty ,Pleural effusion ,030231 tropical medicine ,R895-920 ,macromolecular substances ,gallbladder wall thickening ,Gastroenterology ,Severe dengue ,030218 nuclear medicine & medical imaging ,Dengue fever ,03 medical and health sciences ,Medical physics. Medical radiology. Nuclear medicine ,0302 clinical medicine ,Internal medicine ,Ascites ,medicine ,Radiology, Nuclear Medicine and imaging ,Clinical significance ,gallbladder ,business.industry ,ultrasound ,Gallbladder ,medicine.disease ,dengue ,Gastro-Intestinal Imaging ,medicine.anatomical_structure ,Honeycomb Pattern ,severe dengue fever ,honeycomb pattern ,medicine.symptom ,business - Abstract
Aims and Objectives: To study “Honeycomb” pattern of gallbladder wall thickening (GBWT) in dengue fever (DF) and to assess its clinical significance in early diagnosis of severe DF. Materials and Methods: A total 244 patients of DF were studied, 84 patients were classified as severe DF, 61 patients as DF with warning signs, and 99 patients as DF without warning signs. Abdominal ultrasound was performed for assessment of GBWT patterns, hepatomegaly, splenomegaly, pancreatic enlargement, ascites, pleural effusion, and other additional findings were recorded in severe DF cases. Statistical comparison between “Honeycomb” pattern of GBWT and clinically severe DF was done using Pearson correlation test. Results: Out of 244 patients, 145 patients were males and 99 patients were females, belonging to various age groups ranging from 1 to 81 years and 14.34% (35 patients) among them included in pediatric group. In total, 65.57% (160 patients) were non-severe DF cases and 34.42% (84 patients) were severe DF cases. A total of 84 patients of severe DF, 92.85% patients showed GBWT, and out of which, 71.42% patients had “Honeycomb” pattern, whereas a total of 160 patients of non-severe DF patients, 45% patients had GBWT and out of which, only 5.6% patients showed “Honeycomb” pattern.”Honeycomb” pattern of GBWT shows sensitivity of 71.4%, 94.37%, Positive predictive value of 86.95%, and Negative predictive value of 86.28% in severe DF. Conclusion:”Honeycomb” pattern of GBWT is significant finding in severe DF. Its sensitivity and specificity are high in severe DF with significant statistical correlation. It can aid in early diagnosis of severe DF.
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- 2019
9. Gastric Mucosal Hypertrophy Masquerading as Metastasis From Neuroendocrine Tumor of the Pancreas Detected on 68Ga-DOTANOC PET/CT
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Nikhil Seniaray, Harsh Mahajan, Ethel Shangne Belho, Ritu Verma, Ramkumar Elumalai, and Dharmender Malik
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Male ,Pathology ,medicine.medical_specialty ,Octreotide ,030218 nuclear medicine & medical imaging ,Metastasis ,Lesion ,Diagnosis, Differential ,03 medical and health sciences ,0302 clinical medicine ,Positron Emission Tomography Computed Tomography ,medicine ,Organometallic Compounds ,Humans ,Radiology, Nuclear Medicine and imaging ,Neoplasm Metastasis ,Gastritis, Hypertrophic ,PET-CT ,Somatostatin receptor ,business.industry ,Stomach ,General Medicine ,Middle Aged ,medicine.disease ,Pancreatic Neoplasms ,Neuroendocrine Tumors ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Lymph ,medicine.symptom ,Radiopharmaceuticals ,Pancreas ,business ,medicine.drug - Abstract
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.
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- 2019
10. 18F-FDG PET/CT in Initial Diagnosis and Treatment Response Evaluation of Anti-NMDAr and Anti-GAD Dual Antibody Autoimmune Encephalitis
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Ethel Shangne Belho, Rajeev Kumar Ranjan, Ritu Verma, Nikhil Seniaray, and Harsh Mahajan
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Adult ,Cerebellum ,Pathology ,medicine.medical_specialty ,Hashimoto Disease ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Cerebrospinal fluid ,Fluorodeoxyglucose F18 ,Positron Emission Tomography Computed Tomography ,Basal ganglia ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Abnormal posturing ,Anterior cingulate cortex ,Anti-N-Methyl-D-Aspartate Receptor Encephalitis ,Autoimmune encephalitis ,biology ,business.industry ,General Medicine ,medicine.disease ,Treatment Outcome ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,biology.protein ,Encephalitis ,Female ,Antibody ,business - Abstract
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.
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- 2021
11. Metabolic Imaging Patterns on 18F-FDG PET in Acute and Subacute LGI1 Autoimmune Limbic Encephalitis
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Nikhil Seniaray, Ethel Shangne Belho, Ritu Verma, Harsh Mahajan, and Rajeev Kumar Ranjan
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Pathology ,medicine.medical_specialty ,Disease ,Autoimmune Diseases ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,Fluorodeoxyglucose F18 ,Limbic Encephalitis ,Positron Emission Tomography Computed Tomography ,Extracellular ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Cognitive decline ,Autoantibodies ,Autoimmune encephalitis ,biology ,business.industry ,Autoantibody ,General Medicine ,030220 oncology & carcinogenesis ,Acute Disease ,biology.protein ,Female ,Antibody ,business ,Intracellular - Abstract
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.
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- 2020
12. Diffuse Pulmonary Metastases From Prostate Cancer on 68Ga PSMA PET/CT
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Harsh Mahajan, Ritu Verma, Nikhil Seniaray, Ethel Shangne Belho, and Dharmender Malik
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Male ,medicine.medical_specialty ,Lung Neoplasms ,Gallium Radioisotopes ,Adenocarcinoma ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Antigen ,Prostate ,Positron Emission Tomography Computed Tomography ,medicine ,Carcinoma ,Organometallic Compounds ,Humans ,Radiology, Nuclear Medicine and imaging ,Gallium Isotopes ,PET-CT ,Membrane Glycoproteins ,medicine.diagnostic_test ,business.industry ,68ga psma ,Prostatic Neoplasms ,General Medicine ,Middle Aged ,medicine.disease ,Bronchoalveolar lavage ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Radiology ,Lymph ,Neoplasm Grading ,business - Abstract
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.
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- 2019
13. Unboxing AI - Radiological Insights Into a Deep Neural Network for Lung Nodule Characterization
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Suthirth Vaidya, Vasantha Kumar Venugopal, Akshay Rangasai, Abhijith Chunduru, Vidur Mahajan, Murali Murugavel, Kiran Vaidhya, Digvijay Mahra, and Harsh Mahajan
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medicine.medical_specialty ,Lung Neoplasms ,Biology ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Pulmonary nodule ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Lung ,Artificial neural network ,Solitary Pulmonary Nodule ,Nodule (medicine) ,Bright spot ,medicine.anatomical_structure ,Image database ,030220 oncology & carcinogenesis ,Radiological weapon ,Radiographic Image Interpretation, Computer-Assisted ,National Lung Screening Trial ,Radiology ,Neural Networks, Computer ,medicine.symptom ,Tomography, X-Ray Computed - Abstract
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.
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- 2019
14. Incidental Detection of Skeletal Metastases on 99mTc-DTPA Renography
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Harsh Mahajan, Ritu Verma, Ethel Shangne Belho, and Nikhil Seniaray
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Male ,medicine.medical_specialty ,Lung Neoplasms ,Lumbosacral vertebrae ,Lumbosacral spine ,99mtc dtpa ,Bone Neoplasms ,030218 nuclear medicine & medical imaging ,Lesion ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Technetium Tc 99m Pentetate ,Incidental Findings ,medicine.diagnostic_test ,business.industry ,Radioisotope renography ,General Medicine ,Blood flow ,respiratory system ,Middle Aged ,Bilateral kidneys ,030220 oncology & carcinogenesis ,Radiology ,medicine.symptom ,Radiopharmaceuticals ,business ,Radioisotope Renography - Abstract
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.
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- 2018
15. Giant appendicolith: Rare finding in a common ailment
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Pankaj Arora, Bishwanath Tiwari, Harsh Mahajan, Sanjeev Singhal, Punit Sethi, Anu Singhal, Brahm Prakash, and Sunil Kapur
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medicine.medical_specialty ,Perforation (oil well) ,Population ,Unusual Case ,0211 other engineering and technologies ,lcsh:Surgery ,02 engineering and technology ,giant appendicolith ,Asymptomatic ,laparoscopic appendectomy ,03 medical and health sciences ,0302 clinical medicine ,medicine ,030212 general & internal medicine ,lcsh:RC799-869 ,Laparoscopy ,Abscess ,education ,021110 strategic, defence & security studies ,education.field_of_study ,Acute appendicitis ,medicine.diagnostic_test ,business.industry ,lcsh:RD1-811 ,medicine.disease ,Appendicitis ,Surgery ,lcsh:Diseases of the digestive system. Gastroenterology ,medicine.symptom ,business ,Diverticulum - Abstract
Acute appendicitis is one of the commonest surgical emergencies worldwide. There is considerable variation in prevalence of appendicoliths with appendicitis. Most of the patients with appendicoliths are asymptomatic and they are not pathognomic for acute appendicitis. However, appendicoliths show increased association with perforation and abscess formation. Appendicolith are quite common, being present in 3% of general population and in nearly 10% cases of appendicitis. However, giant appendicoliths measuring over 2 centimeters (cms) are extremely rare. Computed Tomography (CT) has increased their pre-operative diagnosis considerably. Use of spectral analysis can give us the details of composition of the stone pre-operatively. We present a young male diagnosed pre-operatively on Non-Contrast Computed Tomography (NCCT) to have a giant calcium struvite appendicolith. On laparoscopy he had a 3 cm stone and an incidental Meckel's diverticulum and underwent appendectomy. The case is presented for the unique size of the appendicolith alongwith review of literature.
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- 2016
16. Region-specific fMRI dictionary for decoding face verification in humans
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Naman Kohli, Afzel Noore, Shruti Nagpal, Gokulraj T Prabhakaran, Richa Singh, Maneet Singh, Prateekshit Pandey, Daksha Yadav, Harsh Mahajan, and Mayank Vatsa
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Computer science ,Speech recognition ,Caudate nucleus ,Machine learning ,computer.software_genre ,Facial recognition system ,Left fusiform gyrus ,050105 experimental psychology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,0501 psychology and cognitive sciences ,business.industry ,05 social sciences ,Cognition ,Image segmentation ,Human brain ,medicine.anatomical_structure ,Superior frontal gyrus ,Face (geometry) ,Algorithm design ,Artificial intelligence ,business ,computer ,030217 neurology & neurosurgery ,Decoding methods - Abstract
This paper focuses on decoding the process of face verification in the human brain using fMRI responses. 2400 fMRI responses are collected from different participants while they perform face verification on genuine and imposter stimuli face pairs. The first part of the paper analyzes the responses covering both cognitive and fMRI neuro-imaging results. With an average verification accuracy of 64.79% by human participants, the results of the cognitive analysis depict that the performance of female participants is significantly higher than the male participants with respect to imposter pairs. The results of the neuro-imaging analysis identifies regions of the brain such as the left fusiform gyrus, caudate nucleus, and superior frontal gyrus that are activated when participants perform face verification tasks. The second part of the paper proposes a novel two-level fMRI dictionary learning approach to predict if the stimuli observed is genuine or imposter using the brain activation data for selected regions. A comparative analysis with existing machine learning techniques illustrates that the proposed approach yields at least 4.5% higher classification accuracy than other algorithms. It is envisioned that the result of this study is the first step in designing brain-inspired automatic face verification algorithms.
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- 2017
17. High Plasma Glucagon Levels Correlate with Waist-to-Hip Ratio, Suprailiac Skinfold Thickness, and Deep Subcutaneous Abdominal and Intraperitoneal Adipose Tissue Depots in Nonobese Asian Indian Males with Type 2 Diabetes in North India
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Gokulraj Prabakaran, Seema Gulati, Surya P. Bhatt, Anoop Misra, Harsh Mahajan, and Shajith Anoop
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Adult ,Male ,medicine.medical_specialty ,Article Subject ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Abdominal Fat ,India ,Adipose tissue ,030209 endocrinology & metabolism ,Type 2 diabetes ,Intra-Abdominal Fat ,030204 cardiovascular system & hematology ,Glucagon ,lcsh:Diseases of the endocrine glands. Clinical endocrinology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Endocrinology ,Waist–hip ratio ,Asian People ,Internal medicine ,Diabetes mellitus ,medicine ,Humans ,Suprailiac Skinfold Thickness ,lcsh:RC648-665 ,Waist-Hip Ratio ,business.industry ,Fatty liver ,nutritional and metabolic diseases ,medicine.disease ,Skinfold Thickness ,Postprandial ,Diabetes Mellitus, Type 2 ,Body Composition ,business ,Research Article - Abstract
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.
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- 2017
18. Ridge preservation using an in situ hardening biphasic calcium phosphate (β-TCP/HA) bone graft substitute-a clinical, radiological, and histological study
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Nikhil Deshpande, Harsh Mahajan, Ashish Kakar, Aditya Patney, Heiner Nagursky, Annette Lindner, Bappanadu H. Sripathi Rao, and Shashikanth Hegde
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In situ ,Materials science ,business.industry ,Research ,lcsh:R ,Dentistry ,lcsh:Medicine ,030206 dentistry ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Biphasic calcium phosphate ,Implant placement ,lcsh:RK1-715 ,03 medical and health sciences ,0302 clinical medicine ,lcsh:Dentistry ,Alveolar ridge ,Hardening (metallurgy) ,Bone formation ,Implant ,0210 nano-technology ,business ,Cone beam ct - Abstract
Background Post-Extraction ridge preservation using bone graft substitutes is a conservative technique to maintain the width of the alveolar ridge. The objective of the present study was to evaluate an in situ hardening biphasic (HA/β-TCP) bone graft substitutes for ridge preservation without primary wound closure or a dental membrane. Methods A total of 15 patients reported for tooth extraction were enrolled in this study. Implants were placed in average 5.2 ± 2 months after socket grafting. At this visit, Cone Beam CT (CBCT) images and core biopsies were taken. Implant stability (ISQ) was assessed at the insertion as well as at the day of final restoration. Results CBCT data revealed 0.79 ± 0.73 mm ridge width reduction from grafting to implant placement. Histomorphometric analysis of core biopsy samples revealed in average 21.34 ± 9.14% of new bone in the grafted sites. Primary implant stability was high (ISQ levels 70.3 ± 9.6) and further increased until final restoration. Conclusions The results of this study show that grafting of intact post-extraction sockets using a biphasic in situ hardening bone graft substitute results in an effective preservation of the ridge contour and sufficient new bone formation in the grafted sites, which is imperative for successful implant placement.
- Published
- 2016
19. FDG PET/CT with SPM analysis in early diagnosis of clinically suspected osmotic demyelination syndrome with non-contributory MRI
- Author
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Harsh Mahajan, Ethel Shangne Belho, Abhinav Jaimini, Vanshika Gupta, Rajeev Kumar Ranjan, Nikhil Seniaray, Dharmender Malik, and Ritu Verma
- Subjects
0301 basic medicine ,SPM ,medicine.diagnostic_test ,business.industry ,Thalamus ,Magnetic resonance imaging ,030105 genetics & heredity ,medicine.disease ,Statistical parametric mapping ,Pons ,03 medical and health sciences ,0302 clinical medicine ,Positron emission tomography ,Basal ganglia ,FDG PET ,medicine ,Hypermetabolism ,Interesting Image ,Radiology, Nuclear Medicine and imaging ,Nuclear medicine ,business ,Hyponatremia ,030217 neurology & neurosurgery ,MRI - Abstract
Early diagnosis is imperative for adequate management of patients with osmotic demyelination syndrome (ODS), which is usually a result of rapid shifts of osmolality secondary to rapid correction of hyponatremia. Magnetic resonance imaging (MRI) with its special sequences is the investigation of choice for early detection of the osmotic changes in the brain. We report a case of clinically suspected ODS with noncontributory MRI and positive fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) scan with statistical parametric mapping (SPM) analysis, which localized the focal hypermetabolism in the basal ganglia, thalamus, pons, and cerebellum.
- Published
- 2019
20. A Natural Tooth Pontic for Aesthetics- A Case Report
- Author
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Shivangi Mahajan, Harsh Mahajan, Hazari Puja, and Sunil Kumar Mishra
- Subjects
Orthodontics ,Anterior tooth ,business.industry ,medicine.medical_treatment ,0206 medical engineering ,Dentistry ,030206 dentistry ,02 engineering and technology ,Root resorption ,medicine.disease ,020601 biomedical engineering ,Crown (dentistry) ,Masticatory force ,stomatognathic diseases ,03 medical and health sciences ,0302 clinical medicine ,stomatognathic system ,Periodontal disease ,medicine ,Natural tooth ,business ,Lateral incisor - Abstract
Loss of anterior tooth due to any reason like root resorption, trauma, periodontal disease or endodontic failure can be a deeply traumatic situation for most patients & needs immediate attention. An immediate replacement is necessary in order to avoid aesthetic, masticatory & phonetic difficulties. This paper describes the immediate replacement of lateral incisor using composite resin with the natural tooth crown as pontics. It is a simple and economical method. It requires minimal or no tooth preparation tooth & also it is a reversible technique with no additional lab costs.
- Published
- 2016
21. Ga-68 DOTANOC PET/CT imaging in detection of primary site in patients with metastatic neuroendocrine tumours of unknown origin and its impact on clinical decision making: experience from a tertiary care centre in India
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Anjali Jain, Ethel Shangne Belho, Ankur Pruthi, Promila Pankaj, Harsh Mahajan, and Ritu Verma
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medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Stomach ,Gastroenterology ,Rectum ,Standardized uptake value ,medicine.disease ,030218 nuclear medicine & medical imaging ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Oncology ,Prostate ,Positron emission tomography ,030220 oncology & carcinogenesis ,medicine ,Histopathology ,Original Article ,Radiology ,Pancreas ,business - Abstract
Neuroendocrine tumours (NETs) are rare, heterogeneous group of tumours which usually originate from small, occult primary sites and are characterized by over-expression of somatostatin receptors (SSTRs). Positron emission tomography/computed tomography (PET/CT) using Ga-68-labeled-somatostatin-analogues have shown superiority over other modalities for imaging of NETs. The objective of the study was to retrospectively evaluate the efficacy of Ga-68 DOTANOC PET/CT imaging in detecting the primary site in patients with metastatic NETs of unknown origin and its impact on clinical decision making in such patients.Between December 2011 and September 2014, a total of 263 patients underwent Ga-68 DOTANOC PET/CT study in our department for various indications. Out of them, 68 patients (45 males, 23 females; mean age, 54.9±10.7 years; range, 31-78 years) with histopathologically proven metastatic NETs and unknown primary site (CUP-NET) on conventional imaging, who underwent Ga-68 DOTANOC PET/CT scan as part of their clinical work-up were included for analyses. Histopathology (wherever available) and/or follow-up imaging were taken as reference standard. Quantitative estimation of SSTR expression in the form of maximal standardized uptake value (SUVmax) of detected primary and metastatic sites was calculated. Follow-up data of individual patients was collected through careful survey of hospital medical records and telephonic interviews.Maximum patients presented to our department with hepatic metastasis (50 out of 68 patients) and grade I NETs (50%). Ga-68 DOTANOC PET/CT scan identified primary sites in 40 out of these 68 patients i.e., in approximately 59% patients. Identified primary sites were: small intestine [19], rectum [8], pancreas [7], stomach [4], lung [1] and one each in rare sites in kidney and prostate. In one patient, 2 primary sites were identified (one each in stomach and duodenum). Mean SUVmax of the detected primary sites was 25.1±18.0 (median: 16.25; range, 2.1-150). Significant positive correlation was found between SUVmax of detected primary site and SUVmax of the histopathologically proven sites of metastasis (r=0.662; P0.0001). Based on the findings of the Ga-68 DOTANOC PET/CT scan, 3 out of 40 patients underwent definitive treatment for their primary tumour (1 gastric, 1 ileal and 1 prostatic tumour). One patient was being planned for resection of primary rectal lesion at the time of data-collection. Thirty-six out of 68 patients were started on long-acting somatostatin analogues or chemotherapy or targeted therapy. Two patients underwent multiple cycles of peptide receptor radionuclide therapy (PRRNT) using (90)Y and (177)Lu labeled somatostatin analogues.Our findings indicate that Ga-68 DOTANOC PET/CT is a promising imaging modality in patients with metastatic NETs of unknown origin for detection of the primary site and in guiding their therapeutic management.
- Published
- 2016
22. MDCT-based lung volumetry as a prognostic tool—miles to go before we sleep
- Author
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Rohan Shad and Harsh Mahajan
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,business.industry ,030208 emergency & critical care medicine ,Vascular surgery ,Sleep in non-human animals ,Surgery ,Cardiac surgery ,03 medical and health sciences ,0302 clinical medicine ,Cardiothoracic surgery ,medicine ,Lung volumetry ,Cardiology and Cardiovascular Medicine ,business - Published
- 2017
23. High circulating plasma dipeptidyl peptidase- 4 levels in non-obese Asian Indians with type 2 diabetes correlate with fasting insulin and LDL-C levels, triceps skinfolds, total intra-abdominal adipose tissue volume and presence of diabetes: a case–control study
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Ravindra Mohan Pandey, Harsh Mahajan, Seema Gulati, Shajith Anoop, Surya P. Bhatt, and Anoop Misra
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0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Liver span ,Adipose tissue ,030209 endocrinology & metabolism ,Type 2 diabetes ,abdominal obesity ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,medicine ,Asian Indians ,Pathophysiology/Complications ,mri ,Abdominal obesity ,medicine.diagnostic_test ,business.industry ,nutritional and metabolic diseases ,Type 2 Diabetes Mellitus ,medicine.disease ,Metformin ,030104 developmental biology ,Endocrinology ,dp iv ,medicine.symptom ,Lipid profile ,business ,medicine.drug - Abstract
Aim To evaluate circulating plasma dipeptidyl peptidase-4 (DPP4) levels in non-obese Asian Indians with type 2 diabetes mellitus (T2DM), and to correlate these with metabolic profile and measures of anthropometry, skinfolds, abdominal adipose tissue depots, pancreatic volume, and liver span. Methodology Non-obese (body mass index (BMI)
- Published
- 2017
24. Estimation of Liver Span Using MRI for Prediction of Type 2 Diabetes in Non-obese Asian Indians
- Author
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Harsh Mahajan, Kalaivani Mani, Shajith Anoop, Seema Gulati, Ravindra Mohan Pandey, Surya P. Bhatt, and Anoop Misra
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Endocrinology, Diabetes and Metabolism ,Liver span ,Biomedical Engineering ,India ,030209 endocrinology & metabolism ,Bioengineering ,Type 2 diabetes ,Sensitivity and Specificity ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Asian People ,Non obese ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,medicine ,Humans ,030212 general & internal medicine ,Letter to the Editor ,Estimation ,medicine.diagnostic_test ,Asian Indian ,business.industry ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,Endocrinology ,Diabetes Mellitus, Type 2 ,Liver ,ROC Curve ,Area Under Curve ,Cardiology ,Female ,business ,Liver pathology - Published
- 2016
25. Tumor size and its relation to cervical lymph node metastasis and its significance as a prognostic indicator for oral squamous cell carcinomas
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Abhishek Singh Nayyar, Harsh Mahajan, Neetu Punhani, M Jonathan Daniel, KV Chalapathi, and Girish Dongarwar
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Oncology ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Cancer ,Context (language use) ,Magnetic resonance imaging ,General Medicine ,medicine.disease ,030218 nuclear medicine & medical imaging ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Cervical lymphadenopathy ,030220 oncology & carcinogenesis ,Positive predicative value ,Internal medicine ,medicine ,Medical imaging ,medicine.symptom ,business ,Lymph node - Abstract
Context: Oral cancer is the sixth most common cause of cancer-related deaths worldwide. In the Indian scenario, oral cancer is the second most common cancer. The presence of metastatic cervical lymphadenopathy is of particular importance as with every single nodal metastasis, survival of the patient is reduced by one half. Thus, regional metastasis is one of the most important factors in the prognosis and treatment planning of patients with head and neck squamous cell carcinomas. The inaccuracies in clinical examination have been well documented and the diagnostic imaging modalities have been shown to have superior diagnostic accuracy in detecting occult nodal metastasis Considering the numerous uncertainties regarding the progression, management and outcome of oral cancers, an attempt was made to detect the role of tumor size as a predictive indicator for lymph node metastasis using magnetic resonance imaging (MRI). Aim of the Study: The aims of the present study was to evaluate tumor size and its relation to cervical lymph node metastasis and its significance as a prognostic indicator for oral squamous cell carcinomas (OSCCs); and to identify and evaluate inaccuracies of the clinical diagnostic criteria with the help of magnetic resonance imaging (MRI). Materials and Methods: A total number of 27 patients (12 oral cancer-alveolus, 8 oral cancer-tongue, 7 oral cancer-buccal mucosa) attending as out-patients were included in the study. The patients clinically diagnosed and histopathologically proven to have oral squamous cell carcinoma were examined and were evaluated for the tumour size and lymph node status with the help of MRI. Statistical Analysis Used: Values of sensitivity, specificity, positive and negative predictive values and accuracy were calculated. Paired t-test was performed for evaluating size of the tumor and lymph node recorded on clinical and imaging findings. Results: 40% cases were found to be true positive for detecting metastasis using clinical diagnostic criteria whereas 55% cases were found to be true positive for detecting metastasis using imaging criteria. The paired t-test value for the difference in tumor size between clinical and imaging staging was statistically significant (P
- Published
- 2017
26. Coverage of vitamin A supplementation among under-five children in an urban resettlement colony of district Gautam-Budh Nagar, Uttar Pradesh
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Sidhyartha Mukherjee, Shalini Srivastav, and Harsh Mahajan
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Vitamin ,Multivariate analysis ,Traditional medicine ,business.industry ,Under five children ,030209 endocrinology & metabolism ,Bivariate analysis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,Medicine ,030212 general & internal medicine ,Immunization status ,business ,Uttar pradesh ,Demography - Abstract
Background: The Government of India launched the National Vitamin A Prophylaxis Program in 1970. Currently, under this program, a total of nine doses of vitamin A should be given to the children orally, with the first dose at 9�12 months of age, followed by biannual doses at 6-monthly interval up to the age of 5 years. Objective: To evaluate all dose vitamin A supplementation (VAS) coverage and its associated factors and decipher reasons for poor coverage in children aged 12�59 months. Materials and Methods: This study was a cross-sectional survey conducted in Bhangel area of district Gautam-Budh Nagar, Uttar Pradesh, India. The WHO 30-cluster sampling technique was used to select the study subjects. Study subjects included 210 children in the age group of 12�59 months. On the basis of documentary evidence/recall of mothers, the data were recorded in the prestructured pro forma. Bivariate analysis using X2-test was applied to study the association between variables, and multivariate analysis was applied on variables found to be significant on bivariate analysis. Result: Only 6.2% (13/210) children received all doses of Vitamin A due for respective age. The factors found to be significantly associated with VAS coverage were age, religion, and immunization status for VPDs on bivariate analysis and only age group on multivariate analysis. The most common reason for missing the doses of vitamin A was ignorance among parents, which was found in 84.8% (167/197) subjects. Conclusion: Appropriate measures should be taken to improve the national coverage of all dose VAS.
- Published
- 2016
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