Arpit Nagar

Bio: Arpit Nagar is an academic researcher from Ohio State University. The author has contributed to research in topics: Hemangioma & Radiology. The author has an hindex of 13, co-authored 37 publications receiving 678 citations. Previous affiliations of Arpit Nagar include The Ohio State University Wexner Medical Center & University of Texas Health Science Center at San Antonio.

Mesenchymal neoplasms of the kidney in adults: imaging spectrum with radiologic-pathologic correlation.

Abstract: Mesenchymal neoplasms of the kidney in adults cover a wide spectrum with characteristic ontogeny and histologic findings and variable biologic profiles and imaging findings. Benign mesenchymal renal tumors include angiomyolipoma, leiomyoma, hemangioma, lymphangioma, juxtaglomerular cell tumor, renomedullary interstitial cell tumor (medullary fibroma), lipoma, solitary fibrous tumor, and schwannoma. Malignant renal tumors of mesenchymal origin include leiomyosarcoma, rhabdomyosarcoma, angiosarcoma, osteosarcoma, synovial sarcoma, fibrosarcoma, malignant fibrous histiocytoma, and solitary fibrous tumor. Cross-sectional imaging findings for mesenchymal renal tumors in adults are varied. Although angiomyolipomas and lipomas show macroscopic fat, lymphangiomas are cystic in appearance. Renal hemangioma may show phleboliths and a characteristic enhancement pattern. Leiomyoma typically arises from the capsule and causes buckling of the renal cortex. Although osteosarcoma may demonstrate characteristic dense ossification, most renal sarcomas demonstrate imaging features that are indistinguishable from the more common renal cell carcinoma. Although some renal mesenchymal tumors have typical imaging findings, biopsy is warranted to establish a definitive diagnosis. Awareness of the various mesenchymal renal tumors and familiarity with their imaging findings permit optimal patient management.

Current Update on Borderline Ovarian Neoplasms

Abstract: OBJECTIVE. Borderline ovarian tumors comprise a unique group of noninvasive ovarian neoplasms with characteristic histology and variable tumor biology that typically manifest as low-stage disease in younger women with resultant excellent prognosis.CONCLUSION. Borderline tumors are considered to be precursors of low-grade ovarian cancers. Accurate diagnosis and staging facilitate optimal patient management particularly in patients desiring to preserve fertility.

Neoplastic and non-neoplastic proliferative disorders of the perirenal space: cross-sectional imaging findings.

Abstract: The perirenal space, located between the anterior and the posterior renal fasciae, is shaped like an inverted cone with an apex that extends into the iliac fossa. Perirenal tumors and pseudotumors primarily originate either from the kidney or as part of a systemic disease process and have characteristic histopathologic features and biologic behavior. The lesions may be classified on the basis of their distribution and imaging features as solitary soft-tissue masses (renal cell carcinoma, lymphangioma, hemangioma, and leiomyoma), rindlike soft-tissue lesions (lymphoma, retroperitoneal fibrosis, and Erdheim-Chester disease), masses containing macroscopic fat (angiomyolipoma, liposarcoma, myelolipoma, and extramedullary hematopoiesis), and multifocal soft-tissue masses (metastases, plasma cell tumors). Because of overlap in imaging findings among these diverse perirenal lesions, a definitive diagnosis in most cases can be established only at histopathologic analysis. However, an imaging pattern–based approac...

Imaging features of calvarial tuberculosis: a study of 42 cases.

Abstract: BACKGROUND AND PURPOSE: Tuberculosis of the calvaria is a rare entity, and only anecdotal reports describing its imaging features have been previously published in the literature. We report the role of conventional radiography and CT findings on in the evaluation of calvarial tuberculosis in 42 cases. METHODS: Forty-two cases of pathologically verified calvarial tuberculosis were analyzed retrospectively by using conventional radiography and CT imaging. The patients included 28 male and 14 female subjects ranging in age from 5 to 48 years (mean age, 16 years). Surgery was performed in 28 patients, and the remaining 14 patients underwent fine needle aspiration cytology. The histologic findings were consistent with the diagnosis of tuberculosis. At follow-up after 2 years, all patients had completely recovered. RESULTS: The male-to-female ratio was 2:1 (28 male and 14 female). The maximum number of patients affected by calvarial tuberculosis ranged in age from 11 to 20 years (61.2%). The average duration of symptoms was 2.5 months. Thirty-nine (92.8%) patients had subgaleal soft tissue swelling, whereas 31(73.8%) patients had a well-defined lytic lesion in the calvaria. The parietal bone was most commonly affected site of the calvaria (ie, in 22 patients [52.4%]). These lesions were detected at conventional radiography in 34 (80.95%) patients. CT depicted bone destruction in 36 patients (85.7%) cases. Extradural lesions and intraparenchymal pathologies were detected in 22 (52.3%) patients and 5 (11.9%) patients, respectively. CONCLUSION: In calvarial tuberculosis, conventional radiographs of the skull show focal bone destruction often with accompanying soft tissue opacity. CT helps in assessing the extent of bone destruction, scalp swelling, and degree of intracranial involvement. Surgery involving bone debridement is resorted to only in cases where bone destruction is extensive.

Emphysematous cholecystitis: Imaging findings in nine patients

Abstract: Objective: Emphysematous cholecystitis is a severe form of acute cholecystitis and can be rapidly fatal. We present the imaging features of nine patients with proven emphysematous cholecystitis.

Abdominal tuberculosis of the gastrointestinal tract: Revisited

Abstract: Abdominal tuberculosis is an increasingly common disease that poses diagnostic challenge, as the nonspecific features of the disease which may lead to diagnostic delays and development of complications. This condition is regarded as a great mimicker of other abdominal pathology. A high index of suspicion is an important factor in early diagnosis. Abdominal involvement may occur in the gastrointestinal tract, peritoneum, lymphnodes or solid viscera. Various investigative methods have been used to aid in the diagnosis of abdominal tuberculosis. Early diagnosis and initiation of antituberculous therapy and surgical treatment are essential to prevent morbidity and mortality. Most of the patients respond very well to standard antitubercular therapy and surgery is required only in a minority of cases. Imaging plays an important role in diagnosis of abdominal tuberculosis because early recognition of this condition is important. We reviewed our experience with the findings on various imaging modalities for diagnosis of this potentially treatable disease.

Imaging of Uncommon Retroperitoneal Masses

Abstract: Retroperitoneal masses not arising from major solid organs are uncommon. Although there is no simple method of classifying retroperitoneal masses, a reasonable approach is to consider the masses as predominantly solid or cystic and to subdivide these into neoplastic and nonneoplastic masses. Because the treatment options vary, it is useful to be able to differentiate these masses by using imaging criteria. Although the differential diagnosis of retroperitoneal masses can be narrowed down to a certain extent on the basis of imaging characteristics, patterns of involvement, and demographics, there is still a considerable overlap of imaging findings for these masses, and histologic examination is often required for definitive diagnosis. Computed tomography (CT) and magnetic resonance (MR) imaging play an important role in characterization and in the assessment of the extent of the disease and involvement of adjacent and distant structures. Familiarity with the CT and MR imaging features of various retroperitoneal masses will facilitate accurate diagnosis and staging for aggressive lesions.