Chemotherapy response evaluation using diffusion weighted MRI in Ewing Sarcoma: A single center experience.

BACKGROUND: Non-invasive biomarkers for early chemotherapeutic response in Ewing sarcoma family of tumors (ESFT) are useful for optimizing existing treatment protocol. PURPOSE: To assess the role of diffusion-weighted magnetic resonance imaging (MRI) in the early evaluation of chemotherapeutic response in ESFT. MATERIAL AND METHODS: A total of 28 patients (mean age = 17.2 ± 5.6 years) with biopsy proven ESFT were analyzed prospectively. Patients underwent MRI acquisition on a 1.5-T scanner at three time points: before starting neoadjuvant chemotherapy (baseline), after first cycle chemotherapy (early time point), and after completion of chemotherapy (last time point). RECIST 1.1 criteria was used to evaluate the response to chemotherapy and patients were categorized as responders (complete and partial response) and non-responders (stable and progressive disease). Tumor diameter, absolute apparent diffusion coefficient (ADC), and normalized ADC (nADC) values in the tumor were measured. Baseline parameters and relative percentage change of parameters after first cycle chemotherapy were assessed for early detection of chemotherapy response. RESULTS: The responder:non-responder ratio was 21:7. At baseline, ADC ([0.864 ± 0.266 vs. 0.977 ± 0.246]) × 10-3mm2/s; P = 0.205) and nADC ([0.740 ± 0.254 vs. 0.925 ± 0.262] × 10-3mm2/s; P = 0.033) among responders was lower than the non-responders and predicted response to chemotherapy with AUCs of 0.6 and 0.735, respectively. At the early time point, tumor diameter (27% ± 14% vs. 4.6% ± 10%; P = 0.002) showed a higher reduction and ADC (75% ± 44% vs. 52% ± 72%; P = 0.039) and nADC (81% ± 44% vs. 48% ± 67%; P = 0.008) showed a higher increase in mean values among responders than the non-responders and identified chemotherapy response with AUC of 0.890, 0.723, and 0.756, respectively. CONCLUSION: Baseline nADC and its change after the first cycle of chemotherapy can be used as non-invasive surrogate markers of early chemotherapeutic response in patients with ESFT.

Imaging of Bowel Lymphoma: A Pictorial Review.

Intestinal lymphoma, although rare, is the second most common extra-nodal site of lymphoma, following stomach. It is usually secondary to systemic involvement and is predominantly of non-Hodgkin's subtype. In addition to the risk factors for lymphomas occurring elsewhere, certain risk factors are specific for intestinal lymphoma. These include enteropathies such as celiac disease and inflammatory bowel disease. Imaging is the cornerstone in the management of intestinal lymphoma. Contrast-enhanced computed tomography or positron emission tomography-computed tomography are the preferred modalities for diagnosis, staging, monitoring response to treatment, and for follow-up evaluation. Bowel lymphomas can have various morphological patterns on imaging; however, certain characteristic features, if present, may prove invaluable in its diagnosis. Hence, it is imperative to be acquainted with the myriad of imaging findings in bowel lymphoma and its complications which may not only help in vivo distinction from other commoner bowel lesions but alter the management accordingly.

Intracardiac Teratoma in a Child: A Rare Site of a Common Tumor.

Primary intracardiac teratoma is a rare cardiac tumor with few cases reports in neonates and children. The authors present a case of an 8-year-old boy diagnosed with a cystic mass within the heart. The mass lesion was originating from the interventricular septum and was obliterating the ventricular chambers. Clinically, the mass was suspected to be a hydatid cyst. Surgical excision of the cyst was done that was confirmed histopathologically as mature teratoma. Although rare, it should be considered in the differential diagnosis of cystic lesions of heart when evaluating mass lesions in the pediatric age group.

Anomalous origin of left subclavian artery from ascending aorta in a right aortic arch: A case report with review of literature.

We present a case of an 11-year-old boy with a double-outlet right ventricle and a right-sided aortic arch showing anomalous origin of the left subclavian artery from the ascending aorta as the first branch. This case highlights the importance of knowledge of this aberrant anatomy before planning any surgical or endovascular intervention.

An unusual case of periaortitis mimicing aortic aneurysm with coronary artery involvement.

We hereby describe a rare case of coronary artery involvement in a patient with periaortitis which was mimicking an aortic aneurysm on computed tomography (CT). This case also highlights the role of CT in differentiating aortic pathologies to guide the management and also the importance of coronary evaluation in such patients.

Double drainage of total anomalous pulmonary venous connection: An extremely rare variant.

We present a case of rare double drainage of total anomalous pulmonary venous connection, which was diagnosed on a dual-source CT scanner. This case also highlights the critical role of volume-rendered images for preoperative planning.

Absent left common carotid artery in a right aortic arch: Separate origins of left internal and external carotid arteries from brachiocephalic artery.

We present a case of cyanotic congenital heart disease with left common carotid artery agenesis in the setting of the right aortic arch highlighting the potential implications in management.

Current Status of Percutaneous Transhepatic Biliary Drainage in Palliation of Malignant Obstructive Jaundice: A Review.

Malignancies leading to obstructive jaundice present too late to perform surgery with a curative intent. Due to inexorably progressing hyperbilirubinemia with its consequent deleterious effects, drainage needs to established even in advanced cases. Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) are widely used palliative procedures each with its own merits and lacunae. With the current state-of-the-art PTBD technique consequent upon procedural and hardware improvement, it is equaling ERCP regarding technical success and complications. In addition, there is a reduction in immediate procedure-related mortality with proven survival benefit. Nonetheless, it is the only imminent lifesaving procedure in cholangitis and sepsis.

Imaging of Retrosternal Space Lesions - A Pictorial Review.

The retrosternal region (RSS) can be involved by diverse lesions. The RSS is the region behind the sternum and anterior to the ascending aorta. It normally is less than 3 cm deep. Chest X-ray is usually the first imaging modality to raise a suspicion of RSS pathology; however computed tomography is the mainstay to delineate and characterize lesions in this location. Lesions in this location include thyroid, thymic and lymph node lesions; germ cell tumors and vascular lesions. Lesions arising from the sternum, lungs as well as the pleura can also involve this space. The pictorial review depicts the diverse spectrum of lesions in this location.

Case series of urachal adenocarcinoma: Imaging features.

ABSTRACT: Urachal adenocarcinoma is an unusual and aggressive form of bladder cancer that arises from urachus, a midline fibrous remnant of allantois. Experience with diagnosing them is limited and differentiating urachal adenocarcinoma from other urachal pathologies like infected urachal cysts may be difficult at times. Differentials of urachal anomalies can be narrowed down by proper assessment of patient demographics, clinical details, lesion morphology, and imaging findings. With this case series of five patients of urachal adenocarcinoma, we have tried describing their clinical manifestation and imaging appearances.

Deep Learning Model for Quality Assessment of Urinary Bladder Ultrasound Images using Multi-scale and Higher-order Processing.

Autonomous Ultrasound Image Quality Assessment (US-IQA) is a promising tool to aid the interpretation by practicing sonographers and to enable the future robotization of ultrasound procedures. However, autonomous US-IQA has several challenges. Ultrasound images contain many spurious artifacts, such as noise due to handheld probe positioning, errors in the selection of probe parameters and patient respiration during the procedure. Further, these images are highly variable in appearance with respect to the individual patient's physiology. We propose to use a deep Convolutional Neural Network (CNN), USQNet, which utilizes a Multi-scale and Local-to-Global Second-order Pooling (MS-L2GSoP) classifier to conduct the sonographer-like assessment of image quality. This classifier first extracts features at multiple scales to encode the inter-patient anatomical variations, similar to a sonographer's understanding of anatomy. Then, it uses second-order pooling in the intermediate layers (local) and at the end of the network (global) to exploit the second-order statistical dependency of multi-scale structural and multi-region textural features. The L2GSoP will capture the higher-order relationships between different spatial locations and provide the seed for correlating local patches, much like a sonographer prioritizes regions across the image. We experimentally validated the USQNet for a new dataset of the human urinary bladder ultrasound images. The validation involved first with the subjective assessment by experienced radiologists' annotation, and then with state-of-the-art CNN networks for US-IQA and its ablated counterparts. The results demonstrate that USQNet achieves a remarkable accuracy of 92.4% and outperforms the SOTA models by 3 - 14% while requiring comparable computation time.

Abdominal visceral tuberculosis: a malignancy mimic.

The purpose is to discuss abdominal tuberculosis mimicking malignancy involving the abdominal viscera. TB of the abdominal viscera is common, especially in countries where tuberculosis is endemic and in pockets of non-endemic countries. Diagnosis is challenging as clinical presentations are often non-specific. Tissue sampling may be necessary for definitive diagnosis. Awareness of the early and late disease imaging appearances of abdominal tuberculosis involving the viscera that can mimic malignancy can aid detecting TB, providing a differential diagnosis, assessing extent of spread, guiding biopsy, and evaluating response.

IgG4-related cardiovascular disease: imaging features on cardiac computed tomography and magnetic resonance imaging.

We present a case of diffuse involvement of cardiovascular structures in a patient with immunoglobulin4 (IgG4) vasculitis. We also highlight the important role of computed tomography (CT) angiography in diagnosing the same.

Walking the Risk-Benefit Tight Rope: A Case of Post Fine Needle Aspiration Haemorrhage in Extramedullary Plasmacytoma.

BACKGROUND: Primary extramedullary plasmacytomas (EMP) are rare; however, secondary forms may be seen in ~10-15% of patients with systemic multiple myeloma (MM). The diagnosis of EMP is based on the demonstration of monoclonal plasma cells in the lesion, which requires tissue sampling. CASE PRESENTATION: We present a case of a 38 year old female with MM who underwent diagnostic US at our institute. Multiple focal liver lesions were detected, which were suspicious for EMP. She underwent fine needle aspiration cytology (FNAC) for diagnosis, following which she developed hemoperitoneum secondary to deranged clotting parameters (prothrombin time and platelet count). CT angiography revealed active hepatic capsular bleed. She was taken up for percutaneous embolisation, and the supplying vessel successfully embolised using gel foam particles. CONCLUSION: Complications may rarely occur in interventional procedures, particularly in patients with comorbidities. However, prompt diagnosis and management help prevent adverse outcomes.

Imaging update in spinal tuberculosis.

Tuberculosis is ancient disease known to mankind. Diagnosis and management of spinal tuberculosis has immensely improved in last few decades. Imaging, particularly MRI, plays important role in diagnosis of spinal tuberculosis and its complications. Four common imaging patterns of spinal tuberculosis include paradiscal type, central type, Anterior subligamentous type, and posterior type. Imaging also plays important role in differentiation of spinal tuberculosis from its mimics, particularly pyogenic spondylitis, and metastasis. Radiological interventions, such as CT guided vertebral biopsy, and percutaneous drainage of cold abscess, are commonly used in management of spinal tuberculosis. Monitoring of therapeutic response is often based on clinical evaluation and imaging. MRI is most common imaging modality used. Signs of healing include bony ankylosis, resolution of marrow edema, decrease in contrast enhancement, and fatty change with in bone marrow. PET CT is recently evaluated for response assessment with promising results. This review summarizes pathophysiology, clinical presentation, imaging features, radiological interventions, and response assessment in spinal tuberculosis.