Journal of Clinical Imaging Science最新文献

The spleen is a highly vascular organ susceptible to injury in blunt abdominal trauma, often leading to massive blood loss. Splenic artery embolization (SAE) has been shown to be a safe and effective nonoperative approach in cases of hemodynamically stable patients with blunt splenic trauma. SAE can be performed proximally or distally, with both approaches demonstrating similar clinical efficacy. This case report describes emergent splenic embolization for acute abdominal trauma in a liver transplant recipient. However, due to the presence of prior splenic artery ligation, a uniquely alternative route through the gastroepiploic artery was used to gain access to the spleen for embolization.

Renal replacement lipomatosis (RRL), as described by the word, is characterized by abnormal proliferation of the fatty tissue and replacement of renal parenchyma by fat with atrophy of renal parenchyma. This rare condition is mainly attributed to a long-standing disease such as lithiasis. The patient usually presents with non-specific abdominal pain of chronic duration, and imaging is necessary to confirm the diagnosis. Here, we present the case of total RRL presented at our center, diagnosed with ultrasonography, and computerized tomography of kidneys, along with contributing factors and its course of treatment.

Most primary paragangliomas of the head and neck occur in the carotid, jugular body, tympanic ventricle, and vagus nerves. Primary sellar paragangliomas are rare, and their long-term outcomes remain unknown. It is also unclear whether they can be classified as asymptomatic incidentalomas in the sellar region. A 75-year-old man who had been followed up for 15 years for an asymptomatic non-functional pituitary adenoma strongly requested surgery and underwent endoscopic transsphenoidal surgery to remove the tumor. Intraoperatively, the tumor was found to be elastic, harder than the pituitary adenoma, fibrous, and not extremely vascularized. The tumor was excised extracapsularly, although residual tumor tissue remained in the medial part of the bilateral cavernous sinuses. A histopathological assessment revealed negative epithelial markers, positive neuroendocrine markers, and partial positivity for S-100, leading to a diagnosis of paraganglioma. Cervicothoracic and abdominal computed tomography, along with spinal magnetic resonance imaging, revealed no apparent neoplastic lesions. The patient experienced no recurrence for 5 years following the resection. The majority of sellar tumors are pituitary adenomas, craniopharyngiomas, Rathke's cleft cysts, or metastatic brain tumors. Herein, we present a case of an asymptomatic primary sellar paraganglioma that was successfully resected. The case highlights that paraganglioma can be included among incidentalomas in the sellar region. Routine follow-up should generally be recommended for patients with asymptomatic sellar incidentalomas.

Ventriculoperitoneal (VP) shunts are commonly used to treat hydrocephalus by diverting cerebrospinal fluid from the ventricles to the peritoneal cavity. Migration of the VP shunt into the heart and pulmonary artery is a rare complication. Herein, we described a 67-year-old man with a VP shunt catheter that migrated through the venous system into the pulmonary circulation, highlighting early diagnosis with imaging and symptoms.

Objectives: The objectives of the study are to identify usefulness of chest radiography (CXR) and computed tomography (CT) for the assessment of optimal Impella positioning compared to echocardiography.

Material and methods: In this retrospective study, records of 500 patients were reviewed, 95 subjects met the inclusion criteria. The distance from the carina, top of the aortic arch, and in case of CT, from the aortic valve plane to the Impella inlet port was measured. Subjects were stratified into two groups based on echocardiography: Those that did require repositioning and those that did not.

Results: CT revealed greater distance from the carina to the aortic valve plane in patients requiring Impella repositioning compared to those which did not (81.6 ± 15.9 mm vs. 67 ± 13.2 mm, P = 0.019). The distance from the aortic valve plane to the Impella inlet was shorter in repositioned cases on CT (22.3 ± 28.6 mm vs. 35.8 ± 13.3 mm, P = 0.045). The expected location of the aortic valve plane was 6.8 ± 1.3 cm from the carina among CT cases, representing a useful measurement for evaluation on CXR. Significant predictors of aortic valve plane to carina distance on CT were found to be aortic arch to Impella outlet on CXR (P < 0.0001) and carina to Impella outlet on CXR (P < 0.0001).

Conclusions: CT imaging correctly identified patients that required repositioning on echocardiography. Key CT measurements serve as crucial indicators for repositioning and there is notable agreement on measurements across CXR and CT as well as CT and echocardiography in identification of Impella high or low positioning. In addition, there is evidence of significant predictors of CT measurements from CXR.

Objectives: Computed tomography (CT)-guided biopsy is often used to increase the safety and accuracy of biopsies for disease diagnosis. However, CT-guided biopsy is associated with metal artifacts from the biopsy needle and increased patient and operator exposure due to frequent CT fluoroscopy. Therefore, we thought it possible to solve this problem by setting the CT fluoroscopy conditions to a higher tube voltage and a lower tube current-time product (high-tube voltage conditions) than recommended. As a preliminary study, metal artifacts, low-contrast detectability, patient and operator's exposure, and visual changes in high-tube voltage conditions were assessed using phantoms and compared with recommended conditions.

Material and methods: On an interventional radiology CT system, the phantom was scanned under recommended conditions (120 kV, 30 mAs) and high-tube voltage conditions (135 kV, 30-5 mAs). The metal artifacts and low-contrast detectability of each condition were analyzed and compared using the acquired images. In addition, the phantom surface dose assuming patient exposure and the air dose assuming the operator's standing position were measured and compared. Furthermore, visual assessment was performed by six radiological technologists.

Results: Low-contrast detectability was slightly reduced, metal artifacts were significantly lower under high-tube voltage conditions, and patient and operator exposure were lower than the recommended conditions. Furthermore, the findings of the visual assessment were largely consistent with those of the physical assessment.

Conclusion: High-tube voltage conditions in CT fluoroscopy during CT-guided biopsy may be useful in reducing metallic artifacts and patient and operator radiation exposure.

Head and neck cancer is the seventh most common cancer globally, with over 300 thousand deaths annually. Magnetic resonance imaging (MRI) of head and neck tumors is a well-known method for its evaluation, although malignant and benign imaging tumors often overlap. Permeability is an advanced method performed by MRI that assist in the diagnosis and evaluation of the neoplasm treatments, having a well-established role in some cases, such as salivary gland tumors, and promising in others, such as squamous cell carcinoma and lymph node evaluation. This pictorial review aims to demonstrate the diverse applications of magnetic resonance permeability imaging in head and neck tumors, highlighting its role in differentiating benign from malignant lesions, such as parotid gland tumors, assessing head and neck squamous cell carcinoma, and evaluating lymph node involvement. By correlating these advanced imaging findings with conventional magnetic resonance techniques, this review aims to enhance radiologists' understanding of the method and its clinical utility in improving diagnostic and treatment planning.

Objectives: This study evaluated the efficacy of dual-layer spectral detector computed tomography (DLCT) for detecting early ischemic changes (EICs) in patients with acute ischemic stroke (AIS), focusing on electron density (ED) and effective atomic number (effective Z) imaging.

Material and methods: This retrospective study included 15 patients (mean age: 76.5 ± 9.8 years) with AIS who underwent non-contrast computed tomography (CT) with DLCT and magnetic resonance imaging (MRI) on the same day. Quantitative analysis was performed to compare conventional CT, ED, and effective Z values between the infarcted and contralateral brain regions. Qualitative assessment was conducted by two radiologists using the modified Alberta Stroke Program Early CT Score methodology. Receiver operating characteristic curve analysis was performed to evaluate diagnostic performance, and kappa statistics were used to assess interobserver agreement.

Results: Significant differences were observed in the conventional CT and ED values (P < 0.01) but not in effective Z values (P = 0.46) between the infarcted and contralateral regions. ED imaging demonstrated superior diagnostic accuracy (area under curve [AUC] = 0.90) compared with conventional 120-kVp CT (AUC = 0.85) and effective Z imaging (AUC = 0.62). Furthermore, interobserver agreement (kappa = 0.71) was better for ED imaging than for conventional 120-kVp CT (kappa = 0.65). Qualitative analysis revealed that ED images showed better agreement with MRI findings and higher interobserver consistency than conventional 120-kVp images.

Conclusion: Compared with conventional CT, DLCT with ED imaging significantly enhanced detection of EICs in AIS.

This review discusses the evaluation of renal cell carcinoma (RCC) subtypes using computed tomography (CT) and magnetic resonance imaging (MRI). RCC is a malignancy with different histopathological subtypes, constituting approximately 90% of adult kidney tumors. It has been reported that these subtypes show significant differences in terms of clinical behavior, treatment response, and prognosis. In the study, CT and MRI findings of subtypes such as clear cell RCC (ccRCC), papillary RCC (pRCC), chromophobe RCC (chRCC), medullary RCC (mRCC), collecting duct RCC (cdRCC), and multiloculated cystic RCC (mcRCC) were compared. It was stated that CT is the first-choice imaging method in the staging and surgical planning of RCC and provides detailed information about the tumor size, vascularity, and metastatic spread. On the other hand, it has been emphasized that MRI allows better characterization of RCC subtypes with its soft-tissue resolution and contrast agent usage advantage. The study draws attention to the different imaging features of each subtype and details the role of these findings in the clinical decision-making process. It has been stated that ccRCC exhibits intense contrast enhancement and rapid washout pattern in the corticomedullary phase on CT and appears hyperintense on T2A and hypointense on T1 weighted imaging (T1A) on MRI. It has been stated that pRCC has hypovascular features, has lower contrast enhancement, and has homogeneous borders. It has been stated that chRCC has a less vascular structure and exhibits moderate contrast enhancement in the corticomedullary phase. It has been reported that mRCC has invasive features and is usually diagnosed at an advanced stage while cdRCC has a very aggressive clinical course. It has been stated that mcRCC contains distinct cystic areas between the septa, has a well-circumscribed structure, and generally has a low malignancy potential. As a result, it has been stated that detailed evaluation of CT and MRI findings of RCC subtypes plays a critical role in the diagnosis, treatment, and prognosis of these subtypes. It has been emphasized that the findings presented in this study will contribute to the development of more targeted treatment approaches in RCC management.

Congenital portosystemic shunt (CPSS) is a rare vascular anomaly in which portal vein blood flows into the systemic circulation without passing through the liver. They occur in approximately 1 in 30,000-50,000 live births. We present an 11-year-old patient with an extrahepatic CPSS managed with long-term follow-up. The initial clinical presentation showed no significant abnormalities. Subsequent assessments revealed slightly elevated ammonia (NH₃) and total bile acids (TBAs). Two times angiography at the ages of 2 and 11 years confirmed a shunt between the portal vein and left renal vein, with a gradual shift in blood flow dominance from the celiac artery-splenic vein system to the superior mesenteric artery-superior mesenteric vein system as the patient aged. Due to the risk of complications, transcatheter shunt embolization was performed, utilizing 12 coils to achieve complete shunt embolization. Post-embolization, NH3, and TBA levels normalized, and the patient remained asymptomatic. This case highlights the importance of timing in CPSS intervention, particularly with shifting hemodynamics and underscores the need for further studies on optimal intervention timing in pediatric CPSS.