Background: It is of significant importance to assess the extent of hepatic steatosis in living donor liver transplant (LDLT) surgery to ensure optimum graft regeneration as well as donor safety. Aim: To establish the accuracy of non-invasive imaging methods including computed tomography (CT), dual-echo in- and opposed-phase magnetic resonance imaging (MRI), and MR spectroscopy (MRS) for quantification of liver fat content (FC) in prospective LDLT donors with histopathology as reference standard. Settings and Design: This retrospective study was conducted at our institution on LDLT donors being assessed for biliary and vascular anatomy depiction by Magnetic Resonance Cholangiopancreatography (MRCP) and CT scan, respectively, between July 2013 and October 2014. Materials and Methods: Liver FC was measured in 73 donors by dual-echoT1 MRI and MRS. Of these, CT liver attenuation index (LAI) values were available in 62 patients. Statistical Analysis: CT and MRI FC were correlated with histopathological reference standard using Spearman correlation coefficient. Sensitivity, specificity, positive predictive value, negative predicative value, and positive and negative likelihood ratios with 95% confidence intervals were obtained. Results: CT LAI, dual-echo MRI, and MRS correlated well with the histopathology results (r = 0.713, 0.871, and 0.882, respectively). An accuracy of 95% and 96% was obtained for dual-echo MRI and MRS in FC estimation with their sensitivity being 97% and 94%, respectively. False-positive rate, positive predictive value (PPV), and negative predicative value (NPV) were 0.08, 0.92, and 0.97, respectively, for dual-echo MRI and 0.03, 0.97, and 0.95, respectively, for MRS. CT LAI method of fat estimation has a sensitivity, specificity, PPV, and NPV of 73%, 77.7%, 70.4%, and 80%, respectively. Conclusion: Dual-echo MRI, MRS, and CT LAI are accurate measures to quantify the degree of hepatic steatosis in LDLT donors, thus reducing the need for invasive liver biopsy and its associated complications. Dual-echo MRI and MRS results correlate better with histological results in the study, as compared to CT LAI method for fat quantification.

Objective: To evaluate patients who had undergone pyeloplasty for pelviureteric junction obstruction, by measuring the anteroposterior diameter (APD) of the renal pelvis in supine and prone positions, and determine whether a decrease in APD in prone position can exclude obstruction in dilated renal system. Materials and Methods: From January 2012 to December 2013, patients who had undergone pyeloplasty were evaluated by ultrasound in two centers. The difference of APD of the renal pelvis in supine and prone positions was obtained. Correlation was made with the pre- and post-pyeloplasty renal function by radionuclide renogram. Results: There were 42 patients (31 males, 11 females; age range 5 months to 18 years). Residual hydronephrosis was detected in 41 patients of whom 35 patients (85%) showed decrease in APD by >10% in prone position. These patients and the one without hydronephrosis showed either no deterioration or improvement in renal function. Six patients (15%) showed either no change or increase in APD in prone position. Three patients (7.5%) were confirmed to have decrease in renal function indicating obstruction. Three patients (7.5%) showed no deterioration of renal function, but sluggish drainage on radionuclide renogram. C onclusion: Demonstration of decreased APD of renal pelvis in prone position by ultrasound is useful to differentiate obstructed from non-obstructed dilated renal system, and it correctly identified 85% candidates with successful pyeloplasty. In patients with no decrease or increase in APD at prone position, further follow-up is recommended to rule out obstruction.

Biliary anatomy and its common and uncommon variations are of considerable clinical significance when performing living donor transplantation, radiological interventions in hepatobiliary system, laparoscopic cholecystectomy, and liver resection (hepatectomy, segmentectomy). Because of increasing trend found in the number of liver transplant surgeries being performed, magnetic resonance cholangiopancreatography (MRCP) has become the modality of choice for noninvasive evaluation of abnormalities of the biliary tract. The purpose of this study is to describe the anatomic variations of the intrahepatic and extrahepatic biliary tree.

Hydatid disease continues to be a significant health problem in many parts of the world. It can occur in any part of the body, but liver is the commonest site of involvement. The disease may remain asymptomatic for years. Symptoms occur due to compression of local structures or complications like rupture and infection. The diagnosis is clear when typical radiological appearance is observed at the common sites of involvement. Complications give rise to atypical appearances. These coupled with unusual localizations pose diagnostic difficulty. The aim of this pictorial essay is to demonstrate the atypical manifestations of hydatid cysts - atypical either due to complications or the unusual site.

Hepatic complications of malposition of umbilical venous catheter (UVC) are uncommon and occur due to extravasation of hypertonic fluids and the blood products in the liver tissue. Various hepatic complications include thrombosis of hepatic vessels, hepatic necrosis, hepatic fluid collections, and hematoma, with the intraparenchymal liver lesions seen along the course of ductus venosus. Radiologists must be aware of these complications and their imaging findings, as the timely recognition and immediate management can prevent the fatal outcome. Here, we present a rare case of intraparenchymal liver lesions associated with malposition of UVC in a preterm baby.

The application of magnetic resonance imaging (MRI) in pregnancy faced initial skepticism of physicians because of fetal safety concerns. The perceived fetal risk has been found to be unwarranted and of late, the modality has attained acceptability. Its role in diagnosing fetal anomalies is well recognized and following its safety certification in pregnancy, it is finding increasing utilization during pregnancy and puerperium. However, the use of MRI in maternal emergency obstetric conditions is relatively limited as it is still evolving. In early gestation, ectopic implantation is one of the major life-threatening conditions that are frequently encountered. Although ultrasound (USG) is the accepted mainstay modality, the diagnostic predicament persists in many cases. MRI has a role where USG is indeterminate, particularly in the extratubal ectopic pregnancy. Later in gestation, MRI can be a useful adjunct in placental disorders like previa, abruption, and adhesion. It is a good problem-solving tool in adnexal masses such as ovarian torsion and degenerated fibroid, which have a higher incidence during pregnancy. Catastrophic conditions like uterine rupture can also be preoperatively and timely diagnosed. MRI has a definite role to play in postpartum and post-abortion life-threatening conditions, e.g., retained products of conception, and gestational trophoblastic disease, especially when USG is inconclusive or inadequate.

Ultrasonography (USG) is the primary method for antenatal fetal evaluation. However, fetal magnetic resonance imaging (MRI) has now become a valuable adjunct to USG in confirming/excluding suspected abnormalities and in the detection of additional abnormalities, thus changing the outcome of pregnancy and optimizing perinatal management. With the development of ultrafast sequences, fetal MRI has made remarkable progress in recent times. In this pictorial essay, we illustrate a spectrum of structural abnormalities affecting the central nervous system, thorax, genitourinary and gastrointestinal tract, as well as miscellaneous anomalies. Anomalies in twin gestations and placental abnormalities have also been included.

Amniotic band can cause a broad spectrum of anomalies ranging from simple band constrictions to major craniofacial and visceral defects. It can cause significant neonatal morbidity. Accurate diagnosis will help in the management of the present pregnancy and in counseling with regard to future pregnancies. Here we report three cases of amniotic band syndrome detected in the prenatal period.

Testis follows a predictable course during its stepwise descent from its site of origin in the lumbar region to its final destination in ipsilateral hemi-scrotum. Undesended (cryptorchid) testis is more prone for neoplastic transformation. Testicular teratoma is rare relative to ovarian teratoma and occurs rarely prenatally than postnatally. Teratoma is composed of derivatives of three germ layers. Ultrasound with color Doppler is the most commonly used modality for assessment of prenatal status. Prenatal diagnosis of cryptorchid testicular teratoma involves identification of well-defined, complex solid-cystic lesion with calcifications along the path of testicular descent and absent testis in ipsilateral hemi-scrotum at 36 weeks of gestation. Complications associated with cryptorchid testicular teratoma include torsion, hemorrhage, or malignant transformation. Early diagnosis is important to avoid complications, and hence, ultrasound imaging features play an important role in diagnosis.

Congenital high airway obstruction syndrome (CHAOS) causes secondary morphological changes which can be detected on ultrasound. Here we report a case of congenital high airway obstruction with an occipital encephalocele detected at 23 weeks of gestation.

Background: Lower extremity deep vein thrombosis (DVT) is a common illness with an annual incidence of 1 per 1000 adults. The major long-term complication of DVT is post-thrombotic syndrome (PTS) which occurs in up to 60% of patients within 2 years of an episode of DVT. Aims: We aim to evaluate the outcomes of catheter-directed treatment (CDT) for symptomatic acute or subacute lower extremity DVT. Materials and Methods: A retrospective 12-year study was conducted on the outcomes of CDT on 54 consecutive patients who presented with acute or subacute lower extremity DVT to our hospital. Statistical Analysis: Descriptive summary statistics and the Chi-square test were used to measure the outcomes of CDT. Results: Grade 3 thrombolysis was achieved in 25 (46.3%) patients, grade 2 thrombolysis in 25 (46.3%) patients, and grade 1 thrombolysis in 4 (7.4%) patients. Significant recanalization (grade 2 or 3 thrombolysis) was possible in 50 (92.6%) patients. There was no statistically significant difference in the percentage of significant recanalization that could be achieved between patients who underwent CDT before and after 10 days. There was no significant difference between the thrombolysis achieved between urokinase and r-tPA. PTS was seen in 33% of the patients. Major complications were seen in 5.5% of the patients. Conclusion: CDT is a safe and effective therapeutic technique in patients with acute and subacute lower extremity DVT, if appropriate patient selection is made.

Lung cancer continues to be one of the leading causes of death worldwide. In advanced cases of lung cancer, a multimodality approach is often applied, however with poor local control rates. In early non-small cell lung cancer (NSCLC), surgery is the standard of care. Only 15-30% of patients are eligible for surgical resection. Improvements in imaging and treatment delivery systems have provided new tools to better target these tumors. Stereotactic body radiation therapy (SBRT) has evolved as the next best option. The role of radiofrequency ablation (RFA) is also growing. Currently, it is a third-line option in stage 1 NSCLC, when SBRT cannot be performed. More recent studies have demonstrated usefulness in recurrent tumors and some authors have also suggested combination of RFA with other modalities in larger tumors. Following the National Lung Screening Trial (NLST), screening by low-dose computed tomography (CT) has demonstrated high rates of early-stage lung cancer detection in high-risk populations. Hence, even considering the current role of RFA as a third-line option, in view of increasing numbers of occurrences detected, the number of potential RFA candidates may see a steep uptrend. In view of all this, it is imperative that interventional radiologists be familiar with the techniques of lung ablation. The aim of this article is to discuss the procedural technique of RFA in the lung and review the current evidence regarding RFA for NSCLC.

We present two cases of congenital intrahepatic portosystemic shunts in which the right portal vein directly communicated with the inferior venacava (IVC) in one patient and with the hepatic vein in the other. Multiple hepatic nodules consistent with focal nodular hyperplasia (FNH) were seen in the first patient. The second patient presented with recurrent history of hepatic encephalopathy. Percutaneous transhepatic embolization was performed using coils and Amplatz device following which she completely recovered.

Pancreatic arteriovenous malformation (PAVM) is extremely rare; even rarer is its association with pancreatitis. The authors report a case of PAVM causing recurrent episodes of acute pancreatitis in a 46-year-old male. Patient refused surgery and was treated with transcatheter arterial embolization using liquid embolic agent (mixture of n-butyl-2-cyanoacrylate glue and lipiodol), which resulted in a significant decrease in the size of the PAVM.

Hepatic artery pseudoaneurysms (HAP) are uncommon, occurring mostly as a complication of trauma (accidental or iatrogenic). Liver abscess rarely causes HAP and multiple HAP associated with cholangitic abscesses have not been reported in the literature. We present a patient of acute necrotizing pancreatitis with stent block cholangitis and multiple cholangitic abscesses who developed hemorrhagic output through drainage catheter in the liver abscess. A multiphasic CT angiography demonstrated three HAP, which were treated with a combination of endovascular coil embolization and percutaneous thrombin injection. The fact that cholangitic abscesses may be associated with pseudoaneurysms should not be neglected, considering the potentially catastrophic complication and relatively easy radiological management. CT angiography permits accurate diagnosis and lays down the roadmap for endovascular procedures.

Purpose: To study the technical feasibility of tracheobronchial stenting via transnasal route under bronchoscopy and fluoroscopic guidance in severe malignant airway strictures using self-expandable nitinol stents. Materials and Methods: We describe three patients with malignant airway strictures, treated entirely via transnasal route under local anesthesia using bronchoscopic and fluoroscopic guidance. Nasal route allowed convenient access to the airway for the bronchoscope across the stricture and a guidewire was introduced through its working channel. The 18F tracheal stent and the 6F bronchial stent assembly could be easily introduced and deployed under bronchoscopic (reintroduced through the other nostril) and fluoroscopic guidance. Results: We achieved technical success in all the three patients with immediate relief of dyspnea. Conclusion: Transnasal airway stenting with self-expandable nitinol stent using bronchoscopic and fluoroscopic guidance under local anesthesia is a safe and effective method with minimal patient discomfort.

Odontoid process is the central pillar of the craniovertebral junction. Imaging of this small structure continues to be a challenge for the radiologists due to complex bony and ligamentous anatomy. A wide range of developmental and acquired abnormalities of odontoid have been identified. Their accurate radiologic evaluation is important as different lesions have markedly different clinical course, patient management, and prognosis. This article seeks to provide knowledge for interpreting appearances of odontoid on computed tomography (CT) and magnetic resonance imaging (MRI) with respect to various disease processes, along with providing a quick review of the embryology and relevant anatomy.

We describe the clinical, laboratory, and imaging data of three patients who are proven cases of blastomycosis with cranial involvement. In this review, we discuss the imaging features of cranial blastomycosis with relevant clinical case examples including computed tomography (CT), magnetic resonance imaging (MRI), and advanced MR imaging techniques like magnetic resonance spectroscopy (MRS) and MR perfusion. Literature is reviewed for modern-day diagnosis and treatment of this fatal intracranial infection, if not diagnosed promptly and managed effectively.

Duplication of the pituitary gland (DPG) is a very rare developmental anomaly that is often associated with other anomalies - the DPG-plus syndrome and occurs due to splitting of the rostral notochord and prechordal plate during blastogenesis. DPG with the constellation of associated anomalies as in our patient has not been reported previously. This article illustrates the importance of imaging the brain in all patients with obvious midline facial anomalies and the complementary role of MRI and CT in such cases.

Isovaleric acidemia (IVA) is an inborn error of branched chain amino acid metabolism that may manifest as acute neonatal metabolic acidosis or as chronic intermittent form with developmental delay or recurrent episodes of acute metabolic acidosis. Early diagnosis is the key to prevent morbidity and mortality. Brain imaging abnormalities are rarely described in IVA. We report a case of chronic intermittent IVA with acute presentation in a 4-month-old infant who presented with acute metabolic acidosis. Brain magnetic resonance imaging (MRI) revealed symmetric signal intensity changes in bilateral lentiform nuclei with an unreported T1-weighted (T1W) symmetric hyperintense ring-like appearance in bilateral putamen.

Cranial nerve thickening as an initial isolated presentation of CNS lymphoma is rare. Once an extremely rare neoplasm, primary lymphoma of the central nervous system (CNS) now ranks  only next to meningiomas and low-grade astrocytomas in prevalence. Multiple cranial nerve thickening can be a feature of primary CNS lymphoma. Here we report a case of a 45-year-old immunocompetent female who presented with relapsing remitting multiple cranial nerve thickening as an initial feature of primary CNS lymphoma without any other brain or spinal cord lesions.

Paraneoplastic encephalitis is a multifocal inflammatory disorder of the central nervous system (CNS) that is associated with remote neoplasias. The most common malignancy associated with it is bronchial carcinoma, typically small cell carcinoma of lung. It has never been described in association with intracranial neoplasm. We present and discuss the clinical, radiological, and histopathological findings of paraneoplastic encephalitis with intracranial space-occupying lesions (SOLs) in a 55-year-old man. He was thoroughly investigated and biopsy revealed presence of astrocytoma with changes of paraneoplastic encephalitis.

Aim: To assess the positive predictive value (PPV) and inter-observer agreement of Thyroid Imaging Reporting and Data System (TIRADS) as described by Kwak et al. Materials and Methods: This was a prospective study wherein ultrasound was performed by two radiologists on patients with thyroid nodules >1 cm. The third radiologist interpreted archived images. Ultrasound features and TIRADS category were compared with cytology and surgical histopathology. PPV was calculated for all readers' combined assessment. Inter-observer agreement was calculated using linear weighted kappa. Results: A total of 238 patients with 272 nodules of mean size 2.9 ± 1.7 cm were included. PPV for malignancy was 6.6%, 32%, 36%, 64%, 59%, and 91% for TIRADS 2, 3, 4a, 4b, 4c, and 5 categories, respectively. Inter-observer agreement was substantial [kappa (k) = 0.61-0.80] for assessment of nodule echogenicity, margins, calcification, and shape and good (k = 0.570, P < 0.001) for assessment of composition of the thyroid nodules. Overall agreement between observers was substantial for assigning TIRADS category [multi-rater weighted kappa coefficient (wt k) = 0.721, P < 0.001]. Conclusions: TIRADS is a simple and practical method of assessing thyroid nodules with high PPV and good inter-observer agreement.

Tube arcing artifact is known to be caused by a temporary short circuit in the X-ray tube causing momentary loss of X-ray output. It is seen as near-parallel and an equidistant streak pattern on transaxial computed tomography (CT) images and as a "horizontal" hypodense band on the coronal and sagittal CT images. This artifact can be a random occurrence and was caused in this particular case due to voltage fluctuations in the high-voltage supply transformer supplying the rotor of the anode in the X-ray tube. This problem was initially corrected by reducing the tube voltage to 120 kV from the original 140 kV and, subsequently, replacing the faulty transformer. This kind of artifact, which is a very rare situation, can affect the image quality, and could also be an early sign of equipment failure. To the authors' knowledge, such an artifact has not been reported till date in a clinical scenario. Hence, we would like to report a rare situation of tube arcing artifact along with a unique remedy.