Ashu Seith

Whole-body MR imaging with the use of parallel imaging for detection of skeletal metastases in pediatric patients with small-cell neoplasms: comparison with skeletal scintigraphy and FDG PET/CT

BackgroundIn pediatric patients with small-cell tumors, there is an increasing demand for accurate and early detection of skeletal, especially bone marrow, metastases as new treatment protocols are introduced. Whole-body MR imaging (WB-MR) and 18F-fluorodeoxyglucose PET/CT (FDG PET/CT) are new promising imaging methods that can detect metastases before osteoblastic host response occurs, which is the basis for detection of metastases by skeletal scintigraphy (SSC).ObjectiveTo assess the ability of WB-MR to detect marrow metastases in children with small-cell neoplasms and compare its performance with that of FDG PET/CT and SSC.Materials and methodsDuring a 16-month period, 26 children and adolescents with histopathologically proven small-cell neoplasms underwent WB-MR, FDG PET/CT and Tc-phosphonate-based SSC in a random order within a 25-day period. Metastases were localized in relation to eight regions of the body.ResultsWB-MR revealed metastases in 39 out of a total of 208 regions in 26 patients (sensitivity 97.5%, specificity 99.4%, positive predictive value 97.5%, negative predictive value 99.4%), SSC in 12 regions (sensitivity 30%, specificity 99.4%, PPV 92.3%, NPV 85.6%) and FDG PET/CT in 36 regions (sensitivity 90.0%, specificity 100%, PPV 100%, NPV 97.7%). Both WB-MR and FDG PET/CT showed excellent agreement (kappa) with the final diagnosis (96.9% and 93.6% respectively), whereas SSC showed only moderate agreement (39.6%).ConclusionOur results suggest that WB-MR and FDG PET/CT studies are robust imaging modalities for screening for skeletal metastases, and are far more accurate than SSC. The lack of radiation is an additional advantage of WB-MR, especially in the pediatric population.

Transcatheter arterial embolization in the management of hemobilia

BackgroundThis retrospective analysis evaluated the clinical and radiologic results of transcatheter arterial embolization (TAE) in the treatment of significant hemobilia. The imaging findings, embolization technique, complications, and efficacy are described.MethodsThirty-two consecutive patients (21 male, 11 female, age range 8–61 years) who were referred to the radiology department for severe or recurrent hemobilia were treated by TAE. Causes of hemobilia were liver trauma (n = 19; iatrogenic in six and road traffic accident in 13), vasculitis (n = 6), vascular malformations (n = 2), and hepatobiliary tumors (n = 5). Iatrogenic liver trauma was secondary to cholecystectomy in those six patients. Four of five hepatobiliary tumors were inoperable malignant tumors and one was a giant cavernous hemangioma. Arterial embolization was done after placing appropriate catheters as close as possible to the bleeding site. Embolizing materials used were Gelfoam, polyvinyl alcohol particles or steel coils, alone or in combination. Postembolization angiography was performed in all cases to confirm adequacy of embolization. Follow-up color Doppler ultrasound and contrast-enhanced computed tomography was done in all patients.ResultsUltrasonic, computed tomographic, and angiographic appearances of significant hemobilia were assessed. Angiogram showed the cause of bleeding in all cases. Three patients with liver trauma due to accidents required repeat embolization. Eight patients required surgery due to failed embolization (continuous or repeat bleeding in four patients, involvement of the large extrahepatic portion of hepatic artery in two, and coexisting solid organ injuries in two). Severity of hemobilia did not correlate with grade of liver injury. All 13 patients with blunt hepatic trauma showed the cause of hemobilia in the right lobe. No patient with traumatic hemobilia showed an identifiable cause in the left lobe. There were no clinically significant side effects or complications associated with TAE except one gallbladder infarction, which was noted at surgery, and cholecystectomy was performed with excision of the hepatic artery aneurysm.ConclusionTAE is a safe and effective interventional radiologic procedure in the nonoperative management of patients who have significant hemobilia.

Imaging in bronchopulmonary sequestration

Bronchopulmonary sequestration is an uncommon pulmonary disorder characterized by an area of non‐functioning abnormal lung tissue, which receives its blood supply from a systemic artery and characteristically has no connection with the tracheobronchial tree. The abnormal lung tissue is located within the visceral pleura of a pulmonary lobe in the intralobar variety, whereas the extralobar form has its own visceral pleura. The venous drainage of the extralobar type is usually into the systemic veins, whereas the intralobar type drains into the pulmonary veins. Radiological imaging plays a vital role in establishing the diagnosis, and even more importantly, in providing to the clinician a vascular roadmap essential for surgical planning. We present here a review of bronchopulmonary sequestration and also discuss the role of various imaging methods in the early diagnosis and management of these cases.

CT in the Evaluation of Complicated Autosomal Dominant Polycystic Kidney Disease

Purpose: We retrospectively reviewed the CT findings in 24 cases of autosomal dominant polycystic kidney disease (ADPKD) to assess the role of CT in the diagnostic work-up of patients with complicated ADPKD. Material and Methods: Twenty-four patients with ADPKD underwent unenhanced and contrast-enhanced CT for flank pain, haematuria, or fever. The images were retrospectively reviewed for presence of complicated cysts, their morphological features and associated findings in the perinephric space/retroperitoneum. Results: Cyst haemorrhage was present in all patients, seen as high-density cysts, which were mostly bilateral. Most of these cysts had sharply outlined contours, sharp interfaces with adjacent renal parenchyma, imperceptible walls, and homogeneous density, and did not enhance following i.v. contrast administration. However, a few haemorrhagic cysts (9 cysts in 6 patients) showed inhomogeneous density (n = 7), dependent layering of high-density blood leading to fluid-fluid level (n = 2), and contour irregularity (n = 3). CT revealed presence of cyst infection in 6 cases; the involved cysts were larger (average size 4.2 cm) than adjacent cysts, had only a mildly increased or near water density, and showed wall thickening and enhancement. Other findings included air within the infected cyst (n = 1), thickening and enhancement of peri- and paranephric fasciae (n = 5), and abscesses in the posterior paranephric space and adjoining psoas muscle (n = 2). In 2 other patients, although CT suggested cyst infection because of presence of wall enhancement, diagnostic needle aspiration revealed only sterile haemorrhagic fluid. In 1 case, CT revealed a soft tissue density enhancing mass in one of the cysts; this proved to be a renal cell carcinoma by fine-needle biopsy. Calculi were observed in 7 patients, and cyst wall calcification in 11 cases. Conclusion: A combination of unenhanced and contrast-enhanced CT allows correct diagnosis and differentiation amongst the various complications affecting patients with ADPKD. However, in a small subgroup of patients, it may not be possible to differentiate between haemorrhage and infection; such cases require diagnostic needle aspiration for diagnosis.

MRI and MR sialography of juvenile recurrent parotitis

BackgroundJuvenile recurrent parotitis (JRP) is the second most common inflammatory salivary gland disease of childhood, after mumps. Diagnosis of JRP is usually based on clinical history of recurrent unilateral or bilateral parotid swelling and demonstration of sialectasis. Conventional sialography, digital sialography, US, MRI and sialoendoscopy have been used as investigative tools for the diagnosis of JRP. MR sialography is increasingly recognized as a useful supplement to sialography in salivary duct disorders.ObjectiveTo describe the MRI and MR sialographic findings in children with JRP.Materials and methodsMR Sialography was performed using T2-weighted three-dimensional constructive interference in steady-state (CISS) and half fourier acquisition single-shot turbo spin-echo (HASTE) sequences in 62 children with inflammatory salivary gland disease. Out of these 62 children, 6 had JRP. Axial T1- and T2-W images were also performed.ResultsThe main parotid duct was normal in all six children with JRP. High signal intensity focal lesions suggestive of sialectasis were seen involving both parotid glands in all six children. CISS sequence demonstrated the intraglandular ducts and sialectasis better than HASTE images.ConclusionMRI and MR sialography can non-invasively delineate the parenchymal and ductal system abnormalities of the parotid glands in children with JRP. Although MR and MR sialography cannot substitute US, they can accurately depict findings such as sialectasis and signal intensity changes in the parotid gland depending upon the phase of the disease (acute vs. chronic inflammation). The radiologist should be familiar with MR findings of JRP.

Pattern of bone mineral density in patients with sporadic idiopathic hypoparathyroidism

Objective  Measurement of bone mineral density (BMD) in patients with hypoparathyroidism directly addresses the effect of chronic under‐exposure of bone to PTH. Because post‐thyroidectomy hypoparathyroidism is potentially complicated by the pre‐existence of thyrotoxicosis and the need for postoperative thyroxine replacement, we have studied a large group of patients with sporadic hypoparathyroidism who have been followed up in our endocrine clinic. Studies conducted in limited number of patients with sporadic idiopathic hypoparathyroidism (SIH) have suggested an increase in BMD in such patients. In this current study, we have measured BMD in a large cohort of patients with SIH and have assessed the relationship of BMD with duration of disease and with the adequacy of treatment, as indicated by follow‐up serum calcium, phosphate and alkaline phosphatase levels.

Equivalence Randomized Controlled Trial of Bioresorbable Versus Titanium Miniplates in Treatment of Mandibular Fracture: A Pilot Study

PURPOSE The present study was undertaken to test bioresorbable fixation versus titanium for equivalence in terms of clinical union and complications using the American Association of Oral and Maxillofacial Surgeons parameters of care. The study design was a randomized, controlled, equivalence trial. MATERIALS AND METHODS A total of 40 patients were enrolled and allocated to the titanium group and bioresorbable group using a computerized randomization table. All were plated using standard plating principles. In the bioresorbable group, 2 weeks of maxillomandibular fixation was also used. Evaluation of the study endpoint was done at 8 weeks postoperatively. For statistical analysis, the upper limit of the 95% confidence interval was calculated for failure to achieve the primary outcome variable and compared with the maximal clinically acceptable difference between the standard and test modalities in the failure to achieve clinical union (delta). Delta was predetermined as 2%. The other complications were tested for significance using Fishers exact test. RESULTS Of the 40 patients, 21 were in the titanium group and 19 were in the bioresorbable group, with 20 men and 1 woman in the titanium group and 18 men and 1 woman in the bioresorbable group. The mean age was 28.7 years in the titanium group and 26.6 years in the bioresorbable group. In the titanium group, the complications noted were nonunion in 0%, malocclusion in 7.7%, continued postoperative swelling in 0%, chronic pain in 2%, infection in 5.2%, an inability to chew hard food after 8 weeks in 7.7%, the need for alternative treatment in 0%, and the need for reoperation in 31%. In the bioresorbable group, the complications were nonunion in 4.17%, malocclusion in 11.1%, swelling in 8.3%, chronic pain in 37.5%, infection in 0%, an inability to chew hard food in 11.1%, the need for alternative treatment in 11.1%, and need for reoperation for plate removal in 0%. CONCLUSIONS The small sample size did not allow any meaningful conclusion to be drawn from the present study in terms of the primary question of achieving union. Both groups matched in outcomes when evaluated only on a clinical basis. The avoidance of repeat surgery for plate removal is a definite advantage of using resorbable plates. However, the results are inconclusive in favor of any particular plating system.

Insulin response to oral glucose in healthy, lean young women and patients with polycystic ovary syndrome.

Background and aim. Insulin resistance and consequent hyperinsulinemia are common among patients with polycystic ovary syndrome (PCOS). Ethnicity and dietary habits affect insulin levels. There is little published information from India on insulin levels in PCOS patients. Thus the present study aimed to determine the insulin response to oral glucose in women with PCOS and healthy women. Methods. In a case–control study design, women with PCOS and lean healthy women without a family history of diabetes mellitus underwent oral glucose tolerance testing. Samples were collected at 0, 1 and 2 h after glucose ingestion. Results. Two hundred and eighty-five women with PCOS and 27 lean healthy young women were enrolled into the study. The mean age of controls was 22.8 ± 4.5 years (range 15–32 years) and their mean body mass index (BMI) was 19.7 ± 2.6 kg/m2. Mean blood glucose at 0, 1 and 2 h was 88.2 ± 7.2, 115.5 ± 25.5 and 91.8 ± 20.5 mg/dl, respectively. Corresponding plasma insulin levels were 5.8 ± 1.1, 32.7 ± 26.5 and 14.6 ± 9.6 mIU/l. Peak insulin levels were seen at 1 h and these came down to less than 40% of the peak value by 2 h. Glucose/insulin ratio at 0, 1 and 2 h was 15.6 ± 3.1, 7.0 ± 3.1 and 11.4 ± 7.0. Homeostasis model assessment of insulin resistance (HOMA-IR) was 1.2 ± 0.2. The age of the PCOS women ranged from 15 to 40 years (mean 23.4 ± 6.2 years) and their BMI ranged from 16.4 to 50.4 kg/m2 (mean 27.7 ± 6.3 kg/m2). One hundred and seventy-six (62%) PCOS patients had normal glucose tolerance (NGT), 39 (14%) had impaired fasting glucose (IFG), 49 (17%) had impaired glucose tolerance (IGT) and 21 (7%) had type 2 diabetes mellitus (T2DM). Insulin response was higher in women with PCOS. Peak insulin was observed at 1 h. The difference between 1-h and 2-h post-glucose insulin decreased with worsening glucose tolerance. Both plasma insulin and BMI showed a rising trend from NGT to IFG to IGT. There was no further increase in either insulin or BMI from IGT to T2DM. Glucose/insulin ratio at 0, 1 and 2 h was lower (8.3 ± 4.2, 2.0 ± 1.6 and 3.2 ± 3.5) than that of healthy controls. HOMA-IR was 3.1 ± 3.0. Conclusion. Women with PCOS had an exaggerated insulin response to glucose. Thirty-eight percent of PCOS women had some form of abnormal glucose tolerance. Greater insulin response was seen with impairment of glucose tolerance. Obesity had no effect on fasting insulin or insulin response to oral glucose in PCOS women with NGT.

In Vivo Proton Spectroscopy of Giant Cell Tumor of the Bone

OBJECTIVE The proton MR spectroscopic finding of elevated choline has been reported to be useful in the differentiation of malignant from benign musculoskeletal tumors. This study was designed to evaluate the MR spectroscopy features of giant cell tumor (GCT) of the bone, primarily to determine whether the presence of choline is a frequent occurrence in these tumors and whether MR spectroscopy features can be correlated with clinical, radiologic, and histopathologic findings. SUBJECTS AND METHODS MRI, dynamic contrast-enhanced MRI, and proton MR spectroscopy were performed in 33 patients with bone tumors on a 1.5-T MR scanner. Of these, 12 patients who had GCT of the bone form the subject material for this study. Dynamic contrast-enhanced MRI and single-voxel proton MR spectroscopy were performed after preliminary evaluation with radiography. Patients were divided into two groups, those with elevated choline levels and those without a choline peak on MR spectroscopy. The clinical and radiologic features, including the Campanacci stage and dynamic MRI findings, were compared in these two groups. Core biopsy was performed in all patients, and in 10 of 12 patients, histopathologic evaluation of the postoperative resected specimen was also performed. RESULTS Although all 12 tumors were benign on histopathology, four had elevated choline levels. Of these, three (75%) had an aggressive radiographic appearance (Campanacci stage 3). As opposed to this, only three of the eight (37.5%) tumors without a choline peak had an aggressive radiographic appearance. Except for a single case, all tumors showed early enhancement and washout of contrast material on dynamic MRI. CONCLUSION The results of this study indicate that GCT of bone may show raised choline levels on proton MR spectroscopy. This finding is not an indicator of malignancy in these tumors.

Gender Identity of Children and Young Adults with 5α-Reductase Deficiency

Male pseudohermaphroditism (46,XY DSD) due to 5alpha-reductase deficiency has been recognized for the last few decades. There is scant literature on this entity in India. We compiled data on five patients with this disorder. Four of our five patients were reared as females. Our assessment of these children reveals that they had male gender identity from childhood. Three of the four reared as females chose to change gender role at adolescence, while the fourth is still prepubertal. We conclude that all these patients had male gender identity from early childhood. The parents took note of this only after the appearance of male secondary sexual characteristics at puberty, thereby giving an impression of change in gender identity and gender role.