Vikas Chaudhary

Imaging of the pituitary: Recent advances

Pituitary lesions, albeit relatively infrequent, can significantly alter the quality of life. This article highlights the role of advanced imaging modalities in evaluating pituitary-hypothalamic axis lesions. Magnetic resonance imaging (MRI) is the examination of choice for evaluating hypothalamic-pituitary-related endocrine diseases. Advanced MR techniques discussed in this article include dynamic contrast-enhanced MRI, 3T MRI, magnetization transfer (MT) imaging, diffusion-weighted imaging (DWI), proton MR spectroscopy, fluorine-18 fluorodeoxyglucose-positron emission tomography, single-photon emission computed tomography, intraoperative MRI, and intraoperative real-time ultrasonography.

Color doppler evaluation of cerebral-umbilical pulsatility ratio and its usefulness in the diagnosis of intrauterine growth retardation and prediction of adverse perinatal outcome

Objective: The aim of our study was to evaluate the usefulness of the pulsatility index (PI) of the umbilical artery (UA) and that of the fetal middle cerebral artery (MCA), as well as the ratio of the MCA PI to the UA PI (C/U ratio), in the diagnosis of small-for-gestational-age (SGA) fetuses and in the prediction of adverse perinatal outcome. Materials and Methods: The study population comprised 90 pregnancies of 30-41 weeks gestation that had been diagnosed clinically as intrauterine growth retardation (IUGR) over a period of 1 year. The UA PI and the MCA PI as well as the C/U ratio were calculated. Results: Of the 90 pregnancies in the study, 24 showed abnormal UA PI. Among these, 21 (87.5%) were SGA and 19 (79.2%) had adverse perinatal outcome. Of the four of the 90 pregnancies that showed abnormal MCA PI, all were SGA and had adverse perinatal outcome. Similarly, of the 20 out of 90 pregnancies that showed abnormal C/U ratio (<1.08), all 20 (100%) were SGA and had adverse perinatal outcome. The results were correlated with parameters of fetal outcome. Conclusion: Inferences drawn from the study were: (1) The C/U ratio is a better predictor of SGA fetuses and adverse perinatal outcome than the MCA PI or the UA PI used alone, (2) The UA PI can be used to identify IUGR per se and (3) The MCA PI alone is not a reliable indicator for predicting fetal distress.

Imaging of the thyroid: Recent advances

Although thyroid scintigraphy and ultrasound continues to be the mainstay of the diagnostic imaging of the thyroid gland, there have been several recent advances that are of interest to both radiologists and endocrinologists. In this review article, the authors discuss recent progress in imaging of the thyroid by use of radionuclide imaging including single photon-emission computed tomography/positron emission tomography, ultrasonography (USG), USG elastography, computed tomography (CT), magnetic resonance imaging (MRI), and optical coherence tomography.

Imaging of the pancreas: Recent advances

A wide spectrum of anomalies of pancreas and the pancreatic duct system are commonly encountered at radiological evaluation. Diagnosing pancreatic lesions generally requires a multimodality approach. This review highlights the new advances in pancreatic imaging and their applications in the diagnosis and management of pancreatic pathologies. The mainstay techniques include computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), radionuclide imaging (RNI) and optical coherence tomography (OCT).

Pictorial essay: Orbital tuberculosis

Tuberculosis of the orbit is rare, even in places where tuberculosis is endemic. The disease may involve soft tissue, the lacrimal gland, or the periosteum or bones of the orbital wall. Intracranial extension, in the form of extradural abscess, and infratemporal fossa extension has been described. This pictorial essay illustrates the imaging findings of nine histopathologically confirmed cases of orbital tuberculosis. All these patients responded to antituberculous treatment.

Imaging of pancreatic serous cystadenocarcinoma.

Serous cystadenocarcinoma of the pancreas is a rare but well-established entity. The origin of this disorder is speculative, and its evolution remains unclear. On imaging, the malignant behavior of the tumor is best supported by local invasion and/or distant metastasis. The histological characteristics of serous cystadenocarcinoma are indistinguishable from those of its benign counterpart, making the presence of invasion the sole criterion distinguishing the two. The prognosis is excellent even in the face of metastatic disease. We report a case of serous cystadenocarcinoma complicated by recurrent acute and chronic pancreatitis. Initially, no sign of malignancy was seen on imaging. Follow-up study revealed its malignant nature in the form of increased size, presence of duodenal invasion, and multiple liver metastases. The patient underwent Whipple resection with a jejunal Roux-en-Y conduit and microwave coagulonecrotic therapy for metastatic liver lesions. Histopathological examination of the resected specimen revealed a locally invasive cystadenocarcinoma with metastatic disease. One year afterward, the patient is alive with no evidence of progression.

Total pancreatic lipomatosis with malabsorption syndrome

Total fat replacement of the pancreas is rare. Focal fatty replacement is the most common degenerative lesion of pancreas. Focal fatty deposits have no major clinical significance; however, extreme fat replacement is of pathologic significance, as it is associated with marked reduction in exocrine function of pancreas, resulting in malabsorption due to pancreatic enzyme insufficiency.

Symptomatic giant adrenal myelolipoma associated with cholelithiasis: Two case reports.

In this article, we have discussed about two cases of adrenal myelolipoma and aim to discuss the role of imaging in their diagnosis and their management. Different imaging techniques such as ultrasound, computed tomography and magnetic resonance imaging were used to aid in diagnosis in each of the cases. The findings have been highlighted here. In each of the cases, the diagnosis could be confirmed by imaging, and there was cholelithiasis seen associated with unilateral adrenal myelolipoma. Adrenal myelolipomas are rare, benign, non-functional tumors of adrenal gland. Most tumors are unilateral and small; bilateral, giant myelolipomas are extremely rare. The association of adrenal myelolipoma with gallstones is uncommon. To our knowledge only two cases of such an association have been reported in the literature. However, the possibility does exist and steps should be taken to ensure a complete diagnosis. Also, it is important to understand the key points which help us in diagnosing adrenal myelolipomas by imaging.

Pulmonary Langerhans cell histiocytosis in children: A spectrum of radiologic findings

Pulmonary Langerhans cell histiocytosis (PLCH) is a well known entity in adults but is exceedingly rare in children. It is better described in adults than in children. We describe the current understanding of PLCH in children and a spectrum of radiological findings of PLCH in the paediatric population. On high resolution computed tomography (HRCT), PLCH may have variable appearance depending on the stage of disease, ranging from small interstitial nodular opacities to multiple thin/thick walled cysts (often bizarre in shape), eventually leading to marked parenchymal fibrosis and honeycomb pattern. CT finding of PLCH is similar in adult and paediatric populations with the exception that lung base near the costophrenic angle is spared in adults but almost always involved in children.

Neuroimaging of Langerhans cell histiocytosis: a radiological review

The neuroimaging of Langerhans cell histiocytosis (LCH), in most of the cases, is nonspecific and can vary depending on the location, especially as shown on magnetic resonance imaging (MRI). In the absence of a clinical history of LCH, isolated central nervous system (CNS) lesion presents a diagnostic challenge. LCH should be considered in the differential diagnosis of craniofacial tumors and neurodegenerative (ND) lesions of the brain. MRI is the modality of choice for investigating the CNS-LCH. Long-term follow-up with MRI is indicated in patients with ND-LCH. This retrospective study provides a comprehensive description of the spectrum of neuroimaging findings in patients with LCH, the underlying neuropathology, and follow-up study of the disease.