CT and MR imaging of retroperitoneal schwannoma

The purpose of this presentation is to allow the radiologist to discuss the diagnosis of retroperitoneal schwannoma, involving mostly a fortuitous discovery and a misleading clinical presentation. We present 4 cases of retroperitoneal schwannoma, two having benefited from a surgery and two others of a therapeutic abstention. The retropritoneal localization and the imaging are good indicator elements of this pathology. The constant improvement of the CT and MR imaging allows a better approach of this entity also by specifying its localization and its anatomical relationships to guide the therapeutic attitude which must be remain mutidisciplinary.     

Role of diffusion-weighted MR imaging in predicting the grade of nonfunctional pancreatic neuroendocrine tumors

Purpose

The purpose of this study was to describe the magnetic resonance imaging (MRI) findings including diffusion-weighted MRI of nonfunctional pancreatic neuroendocrine tumors (PanNETs) and their hepatic metastases, and investigate the relationships between MRI features and histopathological findings for each grade of PanNETs.

Correlation of quantitative MR imaging findings with symptoms in patients with incidentally detected inflammatory sinonasal disease

Purpose

To assess the relationships between mucosal thickness, T1-weighted, T2-weighted signals and restricted diffusion on magnetic resonance imaging (MRI) with the degree of symptoms in patients with incidentally detected inflammatory sinonasal disease.

Thoracoscopic resection of mediastinal cystic schwannoma

Summary Mediastinal cystic schwannoma is of very rare occurrence. Our patient came with chest pain of 6 months duration. Abnormal shadow on chest x-ray was found. A sharp dissection space was evident by computed tomography (CT-scan) and magnetic resonance imaging (MRI) between the tumor, the left pulmonary artery, and the descending aorta. The patient underwent surgical removal using thoracoscopic surgery. Postoperative discomfort was markedly reduced and hospitalization short. We can conclude that interventional thoracoscopy is a safe, well-tolerated procedure, with excellent therapeutic potentials.     

Preoperative MR imaging for ESMO-ESGO-ESTRO classification of endometrial cancer

Objective

To retrospectively investigate whether magnetic resonance imaging (MRI) findings could contribute to predict histologic type, tumor grade and lymphovascular space invasion (LVSI) to improve preoperative assessment of endometrial cancer using the European Society for Medical Oncology (ESMO) European Society for Radiotherapy & Oncology (ESTRO) and European Society of Gynecological Oncology (ESGO) classification.

Soft tissue sarcoma mimicking chronic hematoma: value of magnetic resonance imaging in differential diagnosis

We report six patients with soft tissue sarcoma mimicking traumatic hematoma. The lesions in these patients, showed huge hematomas and were characterized by rapid growth. Cytology of percutaneous; aspiration biopsy samples was performed in all six patients; however, in five patients, findings for malignant cells were negative. Consequently, they were misdiagnosed, resulting in a poor prognosis. We conducted a retrospective study in which we evaluated the clinical findings, the magnetic resonance (MR) images, and computed tomography (CT) scans of the soft tissue sarcomas forming huge hematomas in the lesion. MR imaging revealed the fine tumor mass with enhancement and characterized the hematoma in the lesion in a more precise fashion than did CT. We conclude that MR imaging is a suitable method for differentiating these soft tissue sarcomas from chronic traumatic hematoma. Received: May 22, 2001 / Accepted: September 12, 2001     

A rare cause of chronic sciatic pain: Schwannoma of the sciatic nerve

Schwannomas are common, benign tumors of the shelth of peripheral nerves. Sciatic schwannomas are rare. Their symptomatology usually mimics sciatic pain due to a herniated disc, which can delay the diagnosis. If there is no lumbar pain and lumbar MRI is normal, the sciatic nerve must be clinically and radiologically examined all along its course. We report a case of sciatic nerve schwannoma presenting with chronic sciatica which was diagnosed and monitored radiologically for several years before successful surgical resection.     

Pancreatic schwannoma: Report of a case

Among pancreatic neoplasms, pancreatic schwannoma is quite rare. We report a case of solitary pancreatic schwannoma, plus a literature review of this tumor. A 71-year-old woman was diagnosed by abdominal ultrasonography as having a pancreatic tumor and was hospitalized in our department at Kumamoto University Hospital on January 26, 2006. Abdominal computed tomography, magnetic resonance imaging, and endoscopic ultrasonography all showed this tumor, which was located in the body of the pancreas, to have cystic and solid components, and with a septum in the cystic part of the lesion. The tumor, preoperatively identified as a mucinous cystic neoplasm, was clearly separated from the normal pancreatic parenchyma. We performed a spleen-preserving distal pancreatectomy with a lymph node dissection on February 7, 2006. A histopathological examination of the resected specimen by means of hematoxylin and eosin revealed the tumor to consist of two parts: one with a compact spindle cell pattern (Antoni type A), and the other showing degeneration of fat (Antoni type B). We also found positive results for immunohistochemical staining for S-100 and vimentin. These findings confirmed the tumor’s classification as a pancreatic schwannoma.     

How to differentiate uterine leiomyosarcoma from leiomyoma with imaging

Uterine leiomyomas, the most frequent benign myomatous tumors of the uterus, often cannot be distinguished from malignant uterine leiomyosarcomas using clinical criteria. Furthermore, imaging differentiation between both entities is frequently challenging due to their potential overlapping features. Because a suspected leiomyoma is often managed conservatively or with minimally invasive treatments, the misdiagnosis of leiomyosarcoma for a benign leiomyoma could potentially result in significant treatment delays, therefore increasing morbidity and mortality. In this review, we provide an overview of the differences between leiomyoma and leiomyosarcoma, mainly focusing on imaging characteristics, but also briefly touching upon their demographic, histopathological and clinical differences. The main indications and limitations of available cross-sectional imaging techniques are discussed, including ultrasound, computed tomography, magnetic resonance imaging (MRI) and positron emission tomography/computed tomography. A particular emphasis is placed on the review of specific MRI features that may allow distinction between leiomyomas and leiomyosarcomas according to the most recent evidence in the literature. The potential contribution of texture analysis is also discussed. In order to help guide-imaging diagnosis, we provide an MRI-based diagnostic algorithm which takes into account morphological and functional features, both individually and in combination, in an attempt to optimize radiologic differentiation of leiomyomas from leiomyosarcomas.     

锁骨骨折手术安全性分区的MRI影像解剖学研究

目的 通过MRI影像解剖学方法研究锁骨骨折手术安全性分区. 方法用核磁共振对13例志愿者锁骨邻近结构进行矢状位和冠状位图像采集.分别测量锁骨下静脉、臂丛神经束移行至锁骨下方时在锁骨投影A点和B点至胸锁关节的距离,以确定具体位置.同时测量钻孔安全深度和安全角度. 结果 A点对应的体表标志为锁骨中内1/3交点(M点);B点对应的体表标志为锁骨全长中点(N点).将锁骨依据手术安全性分区进行如下划分,Ⅰ区为危险区:SJ点(胸锁关节)到M点;Ⅱ区为相对危险区:M点到N点;Ⅲ区为相对安全区:N点到CP'点(喙突在锁骨投影);Ⅳ区为安全区:CP'点到AJ点(肩锁关节).从Ⅰ区至Ⅳ区钻孔安全深度和安全角度数值依次递增. 结论研究锁骨手术安全性分区,可以有效避免手术时的锁骨下神经血管束损伤,降低术中风险.     

呼吸训练对肺部感染者接受磁共振检查质量的影响

目的探讨护士提前应用呼吸训练对肺部感染者在磁共振（MRI）检查中的应用成效。 方法选取2013年1月至2015年1月本院拟接受MRI检查的肺部感染者85例。随机将患者分为观察组和对照组,其中观察组43例,对照组42例;观察组患者中男性27例,女性16例,对照组患者中男性27例,女性15例。观察组平均年龄为（56.0±3.8）岁,对照组平均年龄为（56.4±3.3）岁。两组患者均根据病情需要给予基础护理和呼吸评估,观察组在此基础上,在MRI检查前120 min开始接受呼吸训练,比较两组患者MRI的图像质量及检查耗时。 结果两组患者均完成MRI检查,观察组患者MRI检查图像质量显著优于对照组（U = 3.85、P = 0.000）;观察组患者的图像合格率显著高于对照组（97.67% vs. 76.19%,χ² = 8.704、P = 0.003）。两组患者行MRI平扫,观察组患者耗时显著短于对照组（11.3±1.7 min vs. 14.2±2.2 min,t =-6.81、P = 0.002）。行动态增强扫描,观察组患者检查时长显著短于对照组（4.1±1.0 min vs. 4.1±1.0 min,t =-3.92、P = 0.005）。 结论呼吸训练能够提高患者行MRI检查时的配合度,从而减少由自主性运动引起的MRI图像伪影,提高成像质量,减少检查时间,对小病变的检出率以及临床诊断和鉴别诊断有实际意义。     

Magnetic resonance imaging with magnetic resonance cholangiopancreatography accurately predicts resectability of pancreatic carcinoma

Accurate preoperative staging of pancreatic malignancy aids in directing appropriate therapy and avoids unnecessary invasive procedures. We evaluated the accuracy of magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) in determining resectability of pancreatic malignancy. Twenty-one patients with suspected pancreatic malignancy underwent dynamic, contrast-en-hanced breath-hold MRI with MRCP prior to surgical evaluation. Results of this study were correlated with operative results and pathologic findings. The sensitivity, specificity, and accuracy of MRI with MRCP in detecting a mass, determining the nature of the mass, and predicting lymph node involvement and resectability were determined. MRI with MRCP correctly identified the presence of a pancreatic mass in all 21 of these patients. Following pathologic correlation, it was determined that MRI with MRCP was 81 % accurate in determining the benign or malignant nature of the pancreatic mass and 43% accurate in predicting lymph node involvement. In predicting resectability, MRI with MRCP had a sensitivity of 100%, specificity of 83%, positive predictive value of 94%, negative predictive value of 100%, and accuracy of 95%. MRI with MRCP is an accurate, noninvasive technique in the preoperative evaluation of pancreatic malignancy. Information obtained from MRI with MRCP including identification of a mass and predicting tumor resectability may be of value in staging and avoiding unnecessary invasive diagnostic procedures in patients with pancreatic cancer. Presented at the Thirty-Ninth Annual Meeting of The Society for Surgery of the Alimentary Tract, New Orleans, La., May 17–20, 1998.     

Postoperative MR imaging features after superior semicircular canal plugging in Minor syndrome

Purpose

To report the postoperative magnetic resonance imaging (MRI) features after superior semicircular canal plugging in patients with Minor syndrome.

MR指纹技术在医学影像诊断中的应用

MR指纹技术(MRF)可快速获取定量图像及后处理,其数据采集、后处理及可视化程序设计新颖,可在一次扫描中提供高度可重复的多参数量化图,具有成像时间短、容错率高及成像数据易被计算机识别处理等诸多优势,在临床应用中具有广阔的前景。本文对MRF在医学影像诊断的应用进行综述。     

Characterization of breast lesion using T1-perfusion magnetic resonance imaging: Qualitative vs. quantitative analysis

Objectives

The objective of this study was to quantify the hemodynamic parameters using first pass analysis of T₁-perfusion magnetic resonance imaging (MRI) data of human breast and to compare these parameters with the existing tracer kinetic parameters, semi-quantitative and qualitative T₁-perfusion analysis in terms of lesion characterization.

Sensorineural hearing loss in patients with vestibular schwannoma correlates with the presence of utricular hydrops as diagnosed on heavily T2-weighted MRI

Purpose

The purpose of this study was to assess whether the volume of the vestibular endolymphatic space correlates with the degree of hearing loss using heavily T2-weighted fast imaging employing steady-state acquisition with cycle phase (FIESTA-C) MRI.

Intramedullary and extramedullary schwannoma of the cervical spinal cord—Case report

Intramedullary schwannomas and neurofibromas are rare tumors. Only two cases have been reported as having both an intramedullary and extramedullary component.

We have managed the case of a 15-year-old girl with a schwannoma that appeared to track along the sensory nerve root into the spinal cord. The clinical presentation in this case was that of motor weakness and atrophy, sensory abnormalities, and, late in the course, pain.

Magnetic resonance imaging with gadolinium enhancement was better than myelography and computed tomography at delineating the intramedullary extent of the tumor. The tumor was removed microsurgically at two operative sittings. Reports of this unusual pathology are reviewed.     

Diagnosis and management of vaginal mullerian cyst in a virgin patient

Benign cystic lesions of the vagina are uncommon and may become symptomatic. We describe two symptomatic anterior vaginal wall cysts in a virgin patient and the usefulness of imaging modalities. A 36-year-old virgin woman presented with a complaint of vaginal bulging and pelvic pressure. Pelvic examination revealed a cystic mass protruding from the vagina surrounded by the intact hymen. The initial abdominopelvic ultrasound showed a hypoechoic cystic mass measuring 42 × 20 mm in the vagina. She then had a pelvic magnetic resonance imaging (MRI) that revealed two anterior vaginal wall cysts with no communication with the urethra or bladder. The cysts were excised and histologic examination with mucicarmine revealed mucin-secreting tall columnar cells consistent with a diagnosis of mullerian cyst. While both ultrasonographic examination and MRI are helpful in localizing vaginal cysts, MRI is superior in showing multiple cystic lesions of the vagina and their communication with the surrounding structures.