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1.
Artigo em Inglês | MEDLINE | ID: mdl-38598406

RESUMO

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.

6.
Abdom Radiol (NY) ; 48(8): 2705-2715, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37204509

RESUMO

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.


Assuntos
Neoplasias , Peritonite Tuberculosa , Tuberculose Gastrointestinal , Humanos , Peritonite Tuberculosa/diagnóstico por imagem , Tuberculose Gastrointestinal/diagnóstico por imagem , Abdome/diagnóstico por imagem , Abdome/patologia , Biópsia
7.
Acta Radiol ; 64(4): 1508-1517, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36071615

RESUMO

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.


Assuntos
Sarcoma de Ewing , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Sarcoma de Ewing/diagnóstico por imagem , Sarcoma de Ewing/tratamento farmacológico , Resultado do Tratamento , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética , Critérios de Avaliação de Resposta em Tumores Sólidos , Terapia Neoadjuvante
8.
Indian J Radiol Imaging ; 32(4): 471-478, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36451943

RESUMO

Background Percutaneous radiologic gastrostomy is an established mode of enteral feeding for nutritional support for patients with dysphagia from upper digestive tract malignancy. Its role as a rescue measure in patients with advanced malignancy, presenting with absolute dysphagia and failure of nasogastric tube insertion has not been well established. Purpose This study was performed to assess technical success and long-term outcomes of percutaneous radiologic gastrostomy (push type) for nutritional support for patients with absolute dysphagia as a last ditch nonsurgical rescue effort for enteral access. Materials and Methods This was a prospective observational study of 31 patients who underwent push-type percutaneous radiologic gastrostomy over a period of 2 years (March 2017-March 2019). The study was a part of a larger trial approved by the institutional ethics committee. Patients were followed till the removal of tube, death, or 1 year, whichever was earlier. Gastrostomy tube-related problems and complications were documented. Descriptive summary statistics were employed to analyze the success rate and complications. Results Thirty-one patients with mean age 56 years (26-78 years) including 18 males and 13 females with head and neck squamous cell cancer and esophageal cancer presenting with absolute dysphagia or significant dysphagia with failed nasogastric or endoscopic enteral access were included. Overall technical success was 93.5% (29/31), achieved in 26/31 patients with just fluoroscopy guidance and 3/5 patients with computed tomography guidance. One major (3.3%) and two minor (6.5%) complications were encountered. Five out of 29 gastrostomy tubes had to be exchanged, after a mean of 44 days (1-128 days) after insertion. Conclusion Percutaneous radiologic gastrostomy is a safe and effective intervention even as a rescue measure in patients with absolute dysphagia from advanced upper digestive tract malignancies.

9.
Indian J Radiol Imaging ; 32(4): 441-450, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36451949

RESUMO

Objective Nonspecific aorto-arteritis (NSAA) may involve the myocardium in the form of edema and fibrosis. We conducted this study to investigate role of cardiac MRI including late gadolinium enhancement (LGE), T1 and T2 mapping in the assessment of cardiac involvement in NSAA. Methods and Materials Over the period between 2016 and 2019, 36 patients with NSAA presenting with uncontrolled hypertension, left ventricular dysfunction, congestive cardiac failure, or tachyarrhythmia were included in the study. We also had 16 voluntary control patients for providing normal T1 and T2 mapping values. Results The average age of patients was 27.1 years and the majority were females. MRI is more sensitive than echocardiography in the detection of LV dysfunction and RWMA. Out of 36 patients, 10 (27.8%) had LGE. The most common pattern of midmyocardial enhancement was present in 5 out of 10 patients. Five (13.8%) patients show mid-myocardial enhancement, followed by epicardial enhancement, which was seen in four (11.11%) patients. The values of post-gad T1 mapping values were significantly lower than pre-gad T1 mapping values. At a cut-off global native T1 mapping value of 1019 milliseconds had the sensitivity of 83.3% and specificity of 81.2% in detecting an abnormal T1 map. No significant association of MRI contrast enhancement with elevated ESR and CRP levels. There was no significant relation of myocardial T2 mapping values between NSAA and control groups. Conclusion Quantitative tissue characterization in the myocardium with native T1 mapping values help in the detection of cardiac involvement in patients with NSAA. T1 mapping may provide incremental value in the assessment of myocardial involvement in NSAA in addition to LGE imaging.

10.
Int J Cardiovasc Imaging ; 38(11): 2403-2411, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36434341

RESUMO

T1 and T2 mapping techniques on cardiovascular magnetic resonance (CMR) provide insights into the myocardial tissue characterisation. We sought to establish the normal reference values of native T1 and T2 mapping in Indian population which can be used subsequently in clinical practice for addressing various cardiac pathologies. This prospective study included consecutive healthy volunteers (18-60 years) who underwent CMR on a 1.5 Tesla scanner using standard protocol. T1 mapping sequence was performed using MOLLI sequence with two different flip angles (FA) (35° and 50°). T2 mapping was performed using a hybrid gradient and spin-echo sequence sequence with two different FA (70° and 12°). Images were analysed with ROIs drawn in all the 16 AHA myocardial segments. 50 volunteers (average age-34 years, males-72%) were included. All the scans were normal. The mean T1 value at 35-degree FA was 946.86 + 14.16 ms and at 50-degree FA was 941.60 + 11.89 ms. The mean T2 mapping value at 70-degree FA was 45.67 + 1.39 ms and at 12-degree FA was 45.61 + 1.47 ms. The mapping values were not statistically different between males and females (all p > 0.2). The T1 and T2 mapping values did not show any significant correlation with LVEF, age, BMI or heart rate (all r < 0.33). The T1 mapping values significantly differ at 35- and 50-degree FAs (p = 0.002). The results establish the normal reference T1 and T2 mapping value for Indian population in institutes using the same protocol and parameters at 1.5 Tesla and may guide future research.


Assuntos
Coração , Miocárdio , Masculino , Feminino , Humanos , Valores de Referência , Estudos Prospectivos , Valor Preditivo dos Testes , Miocárdio/patologia
11.
Indian J Thorac Cardiovasc Surg ; 38(4): 451-453, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35756552

RESUMO

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.

13.
Curr Med Imaging ; 18(9): 1012-1015, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35260058

RESUMO

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.


Assuntos
Mieloma Múltiplo , Plasmocitoma , Adulto , Biópsia por Agulha Fina , Feminino , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Humanos , Mieloma Múltiplo/complicações , Mieloma Múltiplo/patologia , Plasmocitoma/complicações , Plasmocitoma/diagnóstico por imagem
14.
J Clin Orthop Trauma ; 25: 101742, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34956831

RESUMO

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.

15.
Dig Dis Sci ; 67(4): 1187-1199, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33877497

RESUMO

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.


Assuntos
Doença Celíaca , Neoplasias Intestinais , Linfoma , Humanos , Neoplasias Intestinais/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Linfoma/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Tomografia Computadorizada por Raios X
16.
Asian Cardiovasc Thorac Ann ; 29(9): 884-892, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34102896

RESUMO

Aortic involvement can be secondary to various pathologic disease processes. These may result in stenotic or aneurysmal aortic lesions with a varied spectrum of imaging findings including intra-luminal, mural, and periaortic changes along with associated loco-regional or distal changes, depending on the etiology. Multidetector computer tomography with its recent advances has become the frontline imaging modality for the evaluation of aortic pathologies. Comprehensive evaluation of the aortic pathology with simultaneous evaluation of lungs, bones, and visceral organs is possible with a single multidetector computer tomography acquisition. It allows accurate primary diagnosis, identifies important anatomic landmarks and relationships, and identifies associated cardiovascular anomalies. Moreover, it serves as an adjunct in diagnosis of various complications, helps in treatment planning and detection of disease progression during follow-up.


Assuntos
Angiografia , Tomografia Computadorizada Multidetectores , Aorta , Angiografia por Tomografia Computadorizada , Constrição Patológica , Humanos , Pulmão
19.
J Card Surg ; 36(3): 1130-1133, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33442902

RESUMO

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.


Assuntos
Aorta Torácica , Artéria Subclávia , Aorta/cirurgia , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Criança , Humanos , Masculino , Artéria Subclávia/diagnóstico por imagem , Artéria Subclávia/cirurgia
20.
J Pediatr Hematol Oncol ; 43(5): e697-e701, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32925407

RESUMO

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.


Assuntos
Neoplasias Cardíacas/patologia , Teratoma/patologia , Criança , Cistos/diagnóstico , Cistos/patologia , Neoplasias Cardíacas/diagnóstico , Ventrículos do Coração/patologia , Humanos , Masculino , Teratoma/diagnóstico
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