Retinoblastoma: CT and MRI

To evaluate the effectiveness of CT and MRI at 0.5 T in the diagnosis and staging of retinoblastoma, we studied 11 patients in whom retinoblastoma was clinically suspected. Nine of the eleven had surgically proven retinoblastoma; in the other two a diagnosis of Coat's disease was made. MRI was not as specific as CT for diagnosing retinoblastoma, due to its lack of sensitivity in detecting calcification; it did, however, have superior contrast resolution. On MRI, Coats' discase was reliably diagnosed and easily differentiated from retinoblastoma. Moreover, the greater ability of MRI to differentiate subretinal fluid from tumour also confers high accuracy in measuring tumour size. CT is still the study of choice in the diagnosis of retinoblastoma, but when MRI is available, it should be performed for better differentiation from lesions such as Coats' disease.     

Diffuse liver disease: MRI with Gd-DTPA versus CT and ultrasound

Twenty-nine patients with diffuse liver disease were examined by ultrasound, CT and MRI. MRI was performed using T1- and T2-weighted spin-echo sequences as well as fast gradient-echo-sequences. The paramagnetic contrast agent Gd-DTPA was applied intravenously (0.1 mmol/kg). in patients with hepatitis, MRI could be used in guiding liver biopsies as inflammatory changes were clearly delineated. CT and ultrasound were superior to MRI in the detection of focal or diffuse fatty degeneration. On the other hand MRI was more helpful in differentiating fatty changes and neoplasm. In liver cirrhosis, fibrotic changes were most clearly demonstrated by MRI. In patients suffering from hemochromatosis MRI offers advantages over CT and ultrasound in the diagnosis and follow up due to the paramagnetic properties of iron, resulting in a reduction in signal intensity. In patients with Wilson's disease a characteristic pattern of parenchymal changes was seen. Administration of Gd- DTPA contributes additional information about perfusion conditions in the liver parenchyma, however this information was not of diagnostic relevance in the cases we studied. Correspondence to: T.J. Vogl     

Spinal cord and cauda equina MRI findings in metachromatic leukodystrophy: case report

Metachromatic leukodystrophy (MLD) is an autosomal recessive disease with well-documented intracranial findings on neuroimaging both by computed tomography (CT) and MRI. We describe the first case of late infantile MLD with spinal involvement revealed by MRI as marked contrast enhancement of nerve roots at the level of the cauda equina.     

烟雾病的DSA、CT和MRI诊断

目的：评价DSA、CT和MBJ对烟雾病的诊断价值。资料和方法：20例病人急性颅内出血起病13例，病情缓慢进展7例，20例DSA检查前有19例行CT检查，2例行MRI检查，1例在DSA检查后行MRI检查。结果：DSA检查具有下列特征性表现：①受累动脉狭窄或闭塞；②脑底部烟雾状毛细血管网；③大量的侧支循环形成。CT14例发现脑室内或蛛网膜下腔出血，3例儿童提示有脑组织内病变，2例表现正常。MRI检查可发现脑内血管性病变。结论：DSA检查是诊断本病的主要手段，具有明显的优点。CT检查对于急性病人一般只能提示出血部位，对于慢性儿童病人常能提示有脑组织内病变。MRI检查，因本组病例太少，其对本病的诊断价值有待进一步探讨。     

CT and MRI findings in cerebral hydatid disease

Cerebal hydatid cysts account for 2% of all intracranial masses. Preoperative diagnosis is important since cyst rupture and spillage may cause an anaphylactic reaction. CT is the primary modality for the diagnosis. Two forms of cerebral hydatid cysts have been reported on the basis of CT appearances: unilocular and multilocular. Demostration of the cyst wall is important for the diagnosis. MRI is superior to CT for demostrating the cyst capsule and perifocal oedema. We retrospectively reviewed the CT and MRI findings of 6 surgically proven cases of cerebal hydatid cyst and compared the two modalities on the basis of their demonstration of findings helpful in the diagnosis, such as the capsule and perifocal oedema. In 1 case CT showed the capsule. In 2 cases MRI showed a hypointense capsule around the cyst on T2-weighted images. While CT is the modality of choice, in clinical practice MRI is superior for demonstrating the cys capsule, which is a helpful findings in the diagnosis and can be used in inconculsive cases. Correspondence to: U. Topal     

CT and MRI of sellar spine with upward extension of the pituitary gland: case report

This is a report of CT and MRI findings in a patient with a sellar spine which caused deformity of the pituitary gland. The sellar spine is an infrequent anatomical variant characterized by an osseous spine which arises in the midline from the anterior aspect of the dorsum sellae and extends into the pituitary fossa. The CT and MRI findings of sellar spine have been described in previous reports; however, only one investigator reported deformity of the pituitary gland as revealed by CT. This is the first report of the MRI finding of the sellar spine associated with a deformity and superior extension of the pituitary gland, mimicking pituitary hypertrophy. Received 6 November 1995; Revision received 29 March 1996; Accepted 9 April 1996     

早期脑动脉硬化的MRI和CT诊断

目的：本文旨在研究ＭＲＩ、ＣＴ对早期脑动脉硬化诊断价值。材料和方法：对７０例早期脑动脉硬化的患者进行ＭＲＩ、ＣＴ检查。结果：６２例ＭＲＩ检查阳性，Ｔ２ＷＩ发现斑点状高信号２８０个，其中额叶１２１个（４３．２％），顶叶２０个（７．１％），基底节７５个（２６．８％），丘脑２６个（９．３％），脑干１５个（５Ａ％），其它部位２４个（８．６％）。ＣＴ对早期脑动脉硬化的敏感性为１２．５％，定性诊断准确率为９４．３％。ＭＲＩ则分别为１００％和９６．４％，ＭＲＩ对微小病变的显示较ＣＴ更优越。结论：ＭＲＩ应作为早期脑动脉硬化的首选检查方法。     

CT and MRI demonstration of cerebral edema in preeclampsia: a report of two cases

In two patients with visual disturbances occurring in preeclampsia CT and MR imaging findings are discussed. Clinical and radiological follow-up indicate reversible edema formation as the most probable cause of the neurological symptoms described. Correspondence to: P.J. Versluis     

Radiographic,CT and MRI spectrum of hydatid disease of the chest: a pictorial essay

Thirty patients with thoracic hydatidosis (Echinococcus granulosus) were studied. The hydatid cysts were located in the lung parenchyma (70%), mediastinum (6.7%), inside the heart (10%), the pleurae (10%) and the chest wall (3.3%). complications of thoracic hydatid cysts, such as rupture, infection, pleural involvement, spread and calcifications are presented. Computed tomography (CT) without and/or with contrast enhancement was performed in all patients (30). Findings from conventional chest radiographs were compared with CT and confirmed by pathology (30). In 10 cases (33.3%), magnetic resonance imaging was also performed. The diagnostic spectrum of hydatid cysts, including variations and developmental stages, is presented in this pictorial essay.     

鼻咽腺样体肥大的MR及CT诊断

目的:探讨腺样体肥大的CT及MR诊断价值及腺样体-鼻咽腔比率(A/N比值)对判断腺样体肥大程度的应用。方法:分析139例腺样体肥大患者的CT及MR表现,其中作CT矢状面图像重组或MR矢状面扫描的42例。重点观察病变部位的形态改变、邻近解剖关系及其并发症,并对其矢状面图像进行A/N比值测定。结果:腺样体肥大的CT及MR表现为鼻咽顶后壁中央弥漫性的软组织增生,呈团块状、山丘样突出或不规则增厚,咽旁间隙及颈动脉鞘区均无浸润表现,邻近骨质无异常改变。腺样体肥大指数A/N比值≥0.71有33例,0.70≥A/N比值≥0.61有7例,A/N比值≤0.60有2例。结论:CT和MR的横断面图像及矢状面图像的A/N比值的测定能准确地诊断腺样体肥大,明确并发症,并能准确量化肥大程度。     

小脑幕脑膜瘤的CT、MRI诊断

目的:探讨小脑幕脑膜瘤的CT、MRI表现,提高其诊断水平。材料和方法:回顾性分析17例经病理证实为小脑幕脑膜瘤的CT、MRI表现。结果:17例小脑幕脑膜瘤中,肿瘤呈哑铃状8例、突向幕下6例和突向幕上3例。CT呈略高密度12例、等密度3例和完全钙化2例。T1WI呈等低信号8例和略高信号5例;T2WI略高信号11例和等信号2例。肿瘤非钙化部分均呈明显增强。结论:小脑幕脑膜瘤的CT、MRI表现较为典型,但单纯CT轴位扫描定位困难,CT多层面重建(MPR)及MRI多方位扫描有助于对其做出正确诊断。     

CT和MRI诊断脑节细胞胶质瘤

目的:分析脑节细胞胶质瘤的CT和MRI表现,探讨其CT、MRI特点。材料和方法:回顾性分析经手术病理证实的12例脑节细胞胶质瘤的MRI表现和6例CT表现。结果:幕上10例和幕下2例。CT平扫肿瘤呈等、低密度,伴高密度钙化3例。T1WI呈等、低信号,4级节细胞胶质瘤1例呈高低混杂信号;T2WI呈高信号或伴等、低信号区。增强扫描1级节细胞胶质瘤无增强2例;2～4级节细胞胶质瘤轻度斑片状增强3例,显著不均匀增强7例。结论:脑节细胞胶质瘤有一些MRI和CT表现特点,结合临床大多数病例可诊断。     

CT and MRI findings with pathological correlation of an intracerebral malignant fibrous histiocytoma (MFH): a case report

The CT and MRI findings in a case of an intracranial malignant fibrous histiocytoma are reported. Pathological correlation was demonstrated and tumour vascularization was best seen at angiography. Despite its low incidence in brain. MFH is of special interest because of its ubiquitous location and poor prognosis.Correspondence to: C. Berchtenbreiter     

Diagnostic potential of virtual cystoscopy of the bladder: MRI vs CT. Preliminary report

The aim of the study was to evaluate the diagnostic potential of the half-Fourier acquired single-shot turbo spin echo (HASTE) sequence for MRI cystoscopy compared with CT cystoscopy and the gold standard conventional cystoscopy. The MRI- and CT cystoscopy was performed in 29 patients with bladder tumors documented at cystoscopy and a control group using a 1.5-T unit (6-mm slice thickness) and a helical CT (3-mm collimation, pitch 1) after filling the bladder with air. Axial MRI and CT images were transferred to a workstation for application of virtual cystoscopy and compared with routine cystoscopy. Axial images and virtual cystoscopies were read by three readers for size and location of tumors. Forty-seven tumors were diagnosed at cystoscopy (12<1 cm, 35≥1 cm). The sensitivity for detection of tumors smaller than 1 cm was 88.9% at MRI cystoscopy and 100% for tumors of 1 cm or larger. These results were not statistically different from the other modalities. Three tumors smaller than 1 cm were not detected at CT cystoscopy, four not all identical at MRI cystoscopy. One tumor with a wall thickening was detected on axial CT and MR images and CT cystoscopy by all observers, but only by two at MRI cystoscopy. The MRI cystoscopy is a diagnostic modality with results comparable to conventional and CT cystoscopy. Electronic Publication     

Intracranial hemorrhage: principles of CT and MRI interpretation

Accurate diagnosis of intracranial hemorrhage represents a frequent challenge for the practicing radiologist. The purpose of this article is to provide the reader with a synoptic overview of the imaging characteristics of intracranial hemorrhage, using text, tables, and figures to illustrate time-dependent changes. We examine the underlying physical, biological, and biochemical factors of evolving hematoma and correlate them with the aspect on cross-sectional imaging techniques. On CT scanning, the appearance of intracranial blood is determined by density changes which occur over time, reflecting clot formation, clot retraction, clot lysis and, eventually, tissue loss. However, MRI has become the technique of choice for assessing the age of an intracranial hemorrhage. On MRI the signal intensity of intracranial hemorrhage is much more complex and is influenced by multiple variables including: (a) age, location, and size of the lesion; (b) technical factors (e.g., sequence type and parameters, field strength); and (c) biological factors (e.g., pO2, arterial vs. venous origin, tissue pH, protein concentration, presence of a blood-brain barrier, condition of the patient). We discuss the intrinsic magnetic properties of sequential hemoglobin degradation products. The differences in evolution between extra- and intracerebral hemorrhages are addressed and illustrated.     

腹部巨大淋巴结增生CT及MRI表现

目的：巨大淋巴结增生的CT和MRI增强表现特点,旨在提高对本病的认识,方法：自1984年1月－2000年5月间,4例巨大淋巴结增生病例接受CT和MRI检查并经手术和病理证实,其中,男2例,女2例,年龄18＝56岁平均41岁,结果：4个病例中2例病灶位于肠系膜,2例位于腹膜后区,局限型3例弥漫型1例,采用动态增强和螺旋CT多期扫描, 灶在动脉期或在动态增强早期明显强化,所有的病灶在延期均表现为持续强化,MRI T1WI 1例表现为低信号,1例为中等信号,T2WI均呈高信号,动态增强扫描病灶的强化方式与CT一致,结论：系膜或腹膜后区富血供的病变,在动脉期明显强化,延迟期持续强化,CT值接近主动脉密谋者,提示巨大淋巴结增生的诊断。     

皮质下动脉硬化性脑病的CT及MRI分析

皮质下动脉硬化性脑病(SAE)是一种老年性脑血管病,又称Binswanger病,是进行性皮质下血管性脑病,是以慢性高血压、脑深部小动脉硬化、皮质下脑白质变性以及多发性腔隙性脑梗死和痴呆为特征的一组综合征[1],是获得性智能障碍性疾病。随着CT、MR的广泛应用,该病的检出率越来越高。按照该病的临床及病理诊断标准,此病并不罕见[2]。作者收集2004年11月~2006年6月在我院确诊为皮质下动脉硬化性脑病的患者共32例,为提高对本病的认识和诊断水平,现分析报告如下。1资料与方法1·1临床资料本组32例,其中男20例,女12例;年龄58~84岁,平均67·2岁。既…     

脑实质海绵状血管瘤的CT和MRI诊断

目的:探讨脑实质海绵状血管瘤(cavernous angioma,CA)的CT、MRI表现及其诊断价值.材料和方法:回顾性分析15例经手术病理证实为CA的CT和MRI表现. 结果: 15例CA共检出19个病灶.CA可发生于脑内任何部位,单发多见(13/15).15例CT和MRI平扫均发现所有病灶.CA的CT平扫均表现为高或稍高密度;CA的MRI平扫表现为T1WI呈等或低信9个,高信号7个,混杂信号3个;T2WI呈高低混杂信号,16个病灶周围伴有低信号环,无占位效应;CT和MRI增强扫描无或轻度增强.结论: CA有典型影像表现,CT和MRI平扫对明确诊断具有重要意义,MRI优于CT,是首选和最佳的影像学方法.     

Rathke囊肿的CT和MRI诊断

目的:分析Rathke囊肿之CT及MRI表现.材料和方法:回顾性分析7例(男3例,女4例,平均年龄32.4岁)经手术病理证实的Rathke囊肿的CT及MRI表现.结果:7例Rathke囊肿中,单纯位于鞍内者3例,直径均小于1.2cm;鞍内鞍上者4例,直径均大于1.2cm.CT及MRI表现根据囊液成分的不同变化多样,增强扫描一般无增强,囊壁极少钙化.结论:垂体Rathke囊肿术前较难明确诊断,仔细分析其CT及MRI表现,有助于提高本病的正确诊断率.     

毛细胞星形细胞瘤的CT、MRI诊断分析

目的探讨毛细胞型星形细胞瘤的CT、MRI特征。方法回顾性分析8例经手术病理证实的毛细胞型星形细胞瘤的CT及MRI表现。结果（1）病变好发于小脑,8例毛细胞星形细胞瘤中,起源于幕下者5例。幕上者3例。（2）肿瘤呈类圆形,伴不同程度囊变,根据囊变程度可分为囊肿型、囊肿结节型和肿块型,以囊肿结节型最多见;（3）肿瘤囊性部分CT平扫呈低密度,MR平扫T1WI呈明显低信号,T2W1呈明显高信号;肿瘤实性部分、囊壁及壁结节CT呈等或稍低密度,MRT1W1呈等或稍低信号,T2WI呈稍高信号。增强后肿瘤囊壁不强化或轻度强化,壁结节及实性部分明显强化,囊性部分不强化;（4）肿瘤边界清楚,瘤周无水肿;（5）肿瘤出血与钙化少见。结论毛细胞型星形细胞瘤在CT、MRI表现具有一定特征性,可为临床术前提供信息。