Reformatted planar 'Christmas tree' MR appearance of the endolymphatic sac.

A high-resolution three-dimensional Fourier transform technique and prototype bilateral dual phased-array surface coil technique was used to make inner ear structures visible on MR. Multiplanar reformatted images, parallel to the plane of the vestibular aqueduct, allowed viewing of the entire endolymphatic sac/vestibular aqueduct on one section, producing a "Christmas tree" shape. The reformation was obtained using a double oblique angle, 45 degrees from true sagittal and 70 degrees from the orbital-meatal axis.     

乳头状内淋巴囊瘤的影像学表现

目的 探讨乳头状内淋巴囊瘤的CT、MRI和DSA特征。方法 回顾性分析总结5例组织病理学证实的乳头状内淋巴囊瘤的CT骨破坏特点及MRI信号特征、强化方式、血液流空情况，4例同时进行DSA检查，以观察血供状态。CT采用常规横轴面平扫和增强扫描；MRI采用SE和快速自旋回波（FSE）及脂肪抑制序列，行矢状、冠状和横轴面平扫和增强扫描。结果 （1）CT表现：肿瘤呈中心位于颞骨岩部迷路后区的溶蚀性骨破坏，病变内含钙化。（2）MRI表现：在未增强T1WI和T2WI，5例肿瘤内见不规则形低信号影，其中心位于颞骨岩部中后部的前庭管外口周围区；3例肿瘤周边显示高信号缘；2例囊实性肿瘤的囊性部分呈高信号，脂肪抑制像高信号不被抑制，而且其边缘更清楚；5例瘤内均见血管流空影。（3）DSA显示肿瘤主要由颈外动脉的分支供血。其中2例还有小脑前下动脉参与供血。结论 乳头状内淋巴囊瘤是位于颞骨岩部迷路后区的具有侵袭性、溶骨性、富含血管的肿瘤，它的影像学特征结合发生部位有助于诊断及鉴别诊断。     

Sudden unilateral deafness with endolymphatic sac adenocarcinoma: MRI

A 30-year-old man presented with sudden left deafness and vertigo. CT showed an osteolytic retrolabyrinthine tumour of the left temporal bone. High signal from the tumour and labyrinth was seen on fat-suppressed T 1-weighted images. At surgery, a haemorrhagic papillary-cystic adenocarcinoma of the endolymphatic sac was found.     

MR imaging, CT, and angiography features of endolymphatic sac tumors: report of two cases

Low-grade adenocarcinoma of endolymphatic sac origin is a rare tumor of the temporal bone. There are some difficulties in its differential diagnosis from other vascular and non-vascular tumors of the temporal bone. However its radiological differentiation from other tumors of the temporal bone is important for surgical planning. We present a report on two endolymphatic sac tumors with some specific radiological findings which can support a correct diagnosis.     

Cerebral schistosomiasis: MR and CT appearance.

After returning from Africa, a 54-year-old man began to have episodes of headache and nausea, then a cerebral convulsion. Clinical and laboratory findings and response to chemotherapy indicated the diagnosis of cerebral schistosomiasis. Three lesions were seen on CT and MR studies: two appeared to be subacute intracerebral hematomas, one in the right parietal lobe and one in the frontal lobe; the third lesion, in the cortex of the left occipital lobe, appeared to be a cyst. These lesions could represent small granulomatous tissue reactions with secondary hemorrhages.     

Pelvic Castleman disease: CT and MR appearance.

The localized form of Castleman disease is rare and of unknown origin. Pelvic location of the disease is unusual. We report the CT and MR appearance of a case of pelvic Castleman disease presenting with characteristic calcifications and hypervascularity.     

MR evaluation of vestibulocochlear anomalies associated with large endolymphatic duct and sac.

BACKGROUND AND PURPOSE: Large endolymphatic duct and sac (LEDS) is one of the most common anomalies seen in patients with congenital sensorineural hearing loss (SNHL), and is known to occur with other inner ear findings. Our purpose was to use high-resolution T2-weighted fast spin-echo (FSE) MR imaging to describe the features and prevalence of specific anomalies that occur in association with LEDS. METHODS: We retrospectively reviewed MR images of the inner ear obtained in 63 patients with LEDS and in 60 control subjects. We evaluated each image for features of cochlear and vestibular dysplasia, including deficiency of the cochlear modiolus, gross cochlear dysmorphism, asymmetry of the cochlear scalar chambers, enlargement of the membranous vestibule, gross vestibular dysmorphism, and abnormality of the semicircular canals (SCC). RESULTS: Cochlear anomalies were present in 76% of ears with LEDS. Modiolar deficiency, gross dysmorphism, and scalar asymmetry were seen in 94%, 71%, and 65% of abnormal cochleas, respectively. Vestibular abnormalities were present in 40% of ears with LEDS. Simple enlargement, gross dysmorphism, and distortion of the lateral SCC were seen in 84%, 16%, and 32% of abnormal vestibules, respectively. CONCLUSION: Coexistent cochlear anomalies, vestibular anomalies, or both are present in most ears with LEDS, and appear as a spectrum of lesions, ranging from subtle dymorphism to overt dysplasia. The presence of coexistent anomalies in LEDS affects treatment decisions and prognosis. Newer techniques of high-resolution FSE MR imaging provide a means of exquisite characterization of LEDS, as well as more sensitive detection of associated vestibulocochlear anomalies.     

Multilocular cystic hemangioma: CT and MR appearance.

An atypical case of multilocular cystic hemangioma is presented. A 4.5 cm multilocular cystic mass was incidentally found in a 66-year-old healthy woman on ultrasound screening. CT, MR imaging, and angiography were performed: however, the features that are characteristic of cavernous hemangioma were not obtained. The final diagnosis could not be made until surgery.     

Ectopic extraspinal meningioma: CT and MR appearance.

We report a case of an ectopic, extraspinal meningioma that appeared as a midline interscapular mass in a 13-year-old girl. The tumor involved the T-2 and T-3 spinous processes, but was dorsal to the lamina and was entirely extrinsic to the spinal canal. Large amounts of tumoral calcification and reactive hyperostosis were present, radiologically mimicking an osteogenic sarcoma.     

Cyclopia: craniofacial appearance on MR and three-dimensional CT.

In a case of alobar holoprosencephaly, a neonate who died several minutes after birth was found to have multiple facial and intracranial malformations, including cyclopia. Postmortem MR and CT findings included a single midline orbit, with two globes that contained separate lenses supplied by a single optic nerve. There were two separate superior orbital fissures and two separate lateral rectus muscles.     

Intraorbital wooden foreign body: CT and MR appearance.

A case of an intraorbital wooden foreign body mimicking air on standard CT window setting and on MR is presented. Its higher attenuation with higher CT window setting as well as its elongated and well-delineated shape on both CT and MR helped to distinguish it from air.     

Serial MR imaging studies in enlarged endolymphatic duct and sac syndrome

European Radiology - Large vestibular aqueduct syndrome (LVAS) is a congenital disorder characterized by progressive or fluctuating sensorineural hearing loss of unknown etiology. Serial MR...     

Elastofibroma: MR and CT appearance with radiologic-pathologic correlation.

OBJECTIVE. The purpose of our study was to determine the MR and CT appearances of elastofibroma and correlate the imaging features with the underlying pathologic findings. MATERIALS AND METHODS. We reviewed retrospectively the MR and CT findings in five cases of elastofibroma. All patients had a soft-tissue mass; one patient also complained of pain. The mean age of the patients was 71 years (range, 63-79 years). Four lesions occurred in the subscapular region, and one occurred in the thigh. In addition, we reviewed and compared the demographic data of 72 histologically proved cases for which we had archival data. RESULTS. Three of four lesions evaluated with spin-echo MR imaging were approximately isointense with skeletal muscle and contained areas with a signal intensity similar to that of fat; these corresponded to areas of dense collagen and interspersed fat, respectively. In the fourth case, the MR appearance was nonspecific. In one case, MR imaging with gadopentetate dimeglumine showed areas with and without enhancement. Three of four lesions evaluated with CT had variable margins, with tissue attenuation similar to that of the adjacent soft tissue as well as scattered areas of decreased attenuation, suggesting fat within the lesion. In one case, the lesion was well defined and relatively homogeneous with an attenuation less than that of skeletal muscle. CONCLUSION. The MR and CT features of elastofibroma are different from those of most other soft-tissue tumors, reflecting entrapped fat within a predominantly fibrous mass. Although these features are not pathognomonic, their presence in a subscapular lesion in an older patient suggests a presumptive diagnosis of elastofibroma.     

Serial MR imaging studies in enlarged endolymphatic duct and sac syndrome

Large vestibular aqueduct syndrome (LVAS) is a congenital disorder characterized by progressive or fluctuating sensorineural hearing loss of unknown etiology. Serial MR examinations were performed before and after the development of hearing loss in two patients with LVAS. The signal and volume of the enlarged endolymphatic sac (EES) vary even in ears with stable hearing. In ears with fluctuating hearing, changes in EES signals were observed in only one of two patients. The finding that the EES volume and signal intensity vary dynamically independently of hearing is important for future research into the pathophysiology of hearing loss in this syndrome.     

Acute epiploic appendagitis in hernia sac: CT appearance

We describe an unusual cause of acute abdomen due to acute epiploic appendagitis located within an incisional hernia sac. The contrast-enhanced CT showed an oval fat density structure with surrounding inflammation in the transverse mesocolon. The contrast-enhanced CT findings of the inflammation of appendices epiploicae of the transverse colon were diagnostic in this case.     

CT and MR appearance of otolaryngologic packing materials.

PURPOSETo examine the CT and MR appearances of four packing materials commonly used in otolaryngologic surgery.METHODSThe CT and MR appearances of bismuth and iodoform paraffin paste, aqueous betadine gauze, calcium sodium alginate, and triadocortyl cream were examined. CT attenuation values were measured using phantoms containing packing materials. MR characteristics were examined by packing the external auditory meati of volunteers. Two illustrative case reports also are presented.RESULTSBismuth and iodoform paraffin paste has a high CT attenuation (> 3000 Hounsfield units) resulting in severe image degradation attributable to streak artifact. Aqueous betadine gauze was of high attenuation (258 Hounsfield units; SD, 16.5) but did not cause image degradation. The attenuation values of calcium sodium alginate and triadocortyl creme coincided with those of muscle and fat, respectively. On MR, calcium sodium alginate and bismuth and iodoform paraffin paste had imaging characteristics similar to muscle and aqueous betadine gauze had appearances similar to bone marrow. Triadocortyl cream had a high signal equal to that of fat on T1-weighted images but a lower signal similar to bone marrow on T2-weighted images.CONCLUSIONSThe presence of bismuth and iodoform paraffin paste can give rise to clinically important image degradation on CT. More seriously, residual packing material may be misinterpreted as infection or tissue necrosis.     

Bicipital radial bursitis: CT and MR appearance

The authors present two cases of bicipital radial bursitis in the elbow. In these two cases, different CT and MR imaging patterns were observed. In the first case, postcontrast CT inhomogeneously enhanced the entire lesion. T1-weighted MR images showed the lesion with iso-signal intensity with muscle. T2-weighted images demonstrated the lesion with inhomogeneous high signal intensity, with internal, linear hypointensity. Histologically, the lesion consisted of hypertrophic synovia. In the second case, postcontrast CT failed to enhance the lesion. T2-weighted MR images showed the lesion with homogeneous, marked high signal intensity. Histologically, the lesion consisted of a monocystic bursa lined by thin synovial lining layers.