Parotid haemangioma. A case report

The presentation of a rare cavernous haemangioma of the parotid in a 17-year-old male is the twenty-first case in the English literature, and the first report in a black adult patient. The aetiology of this lesion is unknown and differs from that of the infantile capillary type. The pathognomonic signs of fluctuating size, discoloration and bruit are rare; the diagnostic hallmark in this case was spontaneous tumour regression. Doppler studies and arteriography may be valuable in diagnosis and management, in which surgical excision is the treatment of choice.     

Anterior cruciate ligament reconstruction: MR imaging findings

More than two million people tear their anterior cruciate ligament (ACL) each year, and ACL reconstruction occupies a significant proportion of everyday orthopedic practice, being one of the most commonly performed sports medicine surgical procedures. Patients with postoperative symptoms are frequently imaged to monitor ligament grafts and to identify complications. Given the number of patients undergoing ACL reconstruction, knowledge of the potential complications of this surgery is essential for radiologists. This article provides a review of imaging of ACL reconstruction procedures and the potential complications specific to this surgery.     

Subtentorial cerebral nocardiosis in immunocompetent patients: CT and MR imaging findings

PurposeTo describe the clinical presentation and computed tomography (CT) and magnetic resonance imaging (MRI) appearances of subtentorial nocardia cerebral abscesses developing in immunocompetent patients.Patients and methodsThe clinical findings and the results of CT and MRI examinations of three immunocompetent patients with nocardiosis located initially only in the subtentorial region were studied. Three patients underwent CT examination and two patients had MRI.ResultsClinically, two patients had cerebellar syndrome and the third had meningism with fever. The diagnosis of nocardiosis was bacteriologically confirmed by demonstrating the organism in lumbar puncture fluid in one patient and by an aspiration biopsy of the abscess in the other two. Two of the patients improved under targeted antibiotic therapy whereas the third patient died. The main imaging features of the lesions were a multiloculated appearance with peripheral enhancement after intravenous administration of iodinated contrast material on CT and a multicystic appearance on MRI, with a peripheral hypointense rim on T2-weighted images, a relatively minor mass effect and a multiloculated appearance on gadolinium-chelate enhanced T1-weighted images.ConclusionThe clinical presentation of cerebral nocardiosis is relatively non-specific. A microcystic lesion surrounded by hypointensity on T2-weighted MR images with a multiloculated pattern after gadolinium chelate administration on T1-weighted MR images in association with a relatively minor mass effect should suggest this diagnosis even if the lesion is single and in the absence of immunosuppression.     

Spinal intradural extramedullary haemangioma: MRI and neurosurgical findings

Summary Haemangiomas, have rarely been encountered in the spinal intradural extramedullary space and the MRI findings of this entity have been described only in a few cases. We present the Magnetic Resonance Imaging (MRI) and surgical findings of a rare case of intradural extramedullary cavernous angioma located at the T1–T2 level in a 65-year-old man presented progressive paraparesis and upper thoracic back pain. On MRI, a well-circumscribed intradural solid mass, 1 cm in diameter, was detected and another enhancing nodular mass was found at the nerve roots of the cauda equina. The thoracic spinal lesion was removed and the histological diagnosis confirmed cavernous haemangioma. Although very uncommon, haemangioma should be included in the differential diagnosis when a spinal intradural extramedullary lesion is discovered and some neuroradiological findings could allow a presumptive diagnosis.     

Two cases of diastematomyelia: its evaluation with MR imaging

We experienced two cases of diastematomyelia. Magnetic Resonance Imaging (MRI) was very useful in definitive diagnosis and detection of associated abnormalities. Case 1 was a 5-year-old boy. He was admitted because of foot-length discrepancy. He also presented scoliosis, hypertrichosis and pigmentation in his back skin, and foot deformity. Myelography and CT myelography revealed bony septum and split cord at midthoracic level, and two separated taut filum terminalis in the lumbosacral region. Sagittal MR image delineated the taut filum terminale adhering to the lipomatous tissue at the end of dural sac. Removal of the septum and division of the taut filum terminalis were performed. Case 2 was a newborn baby. She was admitted because of bulging of the back skin in the lumbosacral region and foot deformity. Plain CT revealed bony septum at lumbar level. Myelography was not performed. MR image demonstrated the split cord in its entirety, the bony septum and its structures in detail, and the associated lipoma. Removal of the septum and resection of the lipoma were performed. Diastematomyelia has been able to be definitely diagnosed only by myelography or CT myelography. In our case, MR image gave visualization of septum and split cord in its entirety, and also detected the associated anomalies such as lipoma, tight filum terminale. MRI has possibility of becoming a diagnostic technique in place of myelography and CT myelography.     

Hepatic haemangioma: Common and uncommon imaging features

The haemangioma, the most common non-cystic hepatic lesion, most often discovered by chance, may in certain situations raise diagnostic problems in imaging. In this article, the authors first demonstrate that the radiological appearance of the hepatic haemangioma, in its typical form, is closely related to three known histological sub-types. They then show that certain atypical features should be known in order to establish a diagnosis. They also observe the potential interactions between the haemangioma, an active vascular lesion, and the adjacent hepatic parenchyma. Finally, they discuss the specific paediatric features of hepatic haemangiomas and illustrate the case of a hepatic angiosarcoma.     

Dissecting aneurysm of the anterior choroidal artery: angiographical and MR imaging findings

BACKGROUND: Intracranial dissecting aneurysms are relatively rare. We present a rare case of a dissecting aneurysm originating from the anterior choroidal artery; this is the first reported case.CASE DESCRIPTION: A 42-year-old man suffered sudden onset of right hemiparesis and dysarthria. Computed tomography on admission revealed a small low density area in the posterior limb of the internal capsule. MR imaging revealed aneurysmal dilatation of the anterior choroidal artery, and angiography revealed aneurysmal dilatation and stasis of dye in the venous phase at the anterior choroidal artery, which resolved in the chronic stage.CONCLUSION: We describe a rare case of a dissecting aneurysm of the anterior choroidal artery. The radiological findings were characteristic of dissecting aneurysms in spite of the rare location.     

Recent advances in MR imaging: FLAIR imaging

Fluid-attenuated inversion recovery (FLAIR) imaging is a technique that increases the sensitivity of magnetic resonance imaging to detect central nervous system (CNS) diseases characterized by an increase in interstitial water content such as brain tumors, cerebral infarcts, and gliotic scars. A role for this technique in subarchnoid disease processes such as hemorrhage and epidermoid tumor is also being revealed.     

Evaluation of 9.4-T MR microimaging in assessing normal and defective fetal bone development: comparison of MR imaging and histological findings

We evaluated 9.4-T magnetic resonance (MR) microimaging in assessing normal and defective bone development in mouse embryos. For this purpose, we performed 9.4-T MR microimaging on developing bones in normal embryos, and also in Runx2/Cbfa1-/- embryos with severely defective bone development. MR images were compared with the histological and histochemical features of these fetal bones. MR microimaging delineate successfully the normal long bone development in embryos. The T1- and T2-weighted MR microimaging demonstrated chondrocyte maturation in different regions of growing cartilage, such as epiphysis, physis, hypertrophic cartilage, and zone of provisional calcification. These developmental changes were detectable in as early as E14.5 embryos. The MR microimaging clearly demonstrated defective bone development in Runx2/Cbfa1-/- embryos. The femur from E18.5 homozygous Runx2/Cbfa1-/- embryos lacked MR signal intensity patterns including the hypertrophic cartilage, which are characteristic of the bone from the age-matched Runx2/Cbfa1+/+ embryos. Interestingly, however, the tibia from the same mutants was associated with MR signal patterns indicative of hypertrophic cartilage but not of the primary spongiosa and ossifying perichondrium, suggesting that bone development is differently regulated in these two long bones. On the other hand, the bones from heterozygous Runx2/Cbfa1+/- embryos exhibited an MR phenotype intermediate between the Runx2/Cbfa1+/+ and Runx2/Cbfa1-/- embryos; the primary spongiosa and ossifying perichondrium formation occurred normally even in the absence of preceding organized maturation of chondrocytes, a phenotype that was not detected by histological examinations. We concluded that MR microimaging is useful in assessing the bone development.     

Parotid lymphomas--clinical and computed tomographic imaging features

OBJECTIVE: To review the clinical presentation and computed tomography (CT) imaging characteristics of all parotid lymphomas diagnosed at the study institution over a 7-year period. DESIGN: Retrospective chart review of parotid lymphomas diagnosed between 1997 and 2004. SUBJECTS: A total of 121 patients with parotid lesions were identified. After retrospective chart review, a total of 10 patients with histologically proven parotid lymphoma were included in the study, 8 of whom had CT scans available for assessment. RESULTS: Ten patients with histologically proven lymphoma of the parotid gland were identified from among 121 patients with parotid neoplasms, an incidence in this series of 8.3%. All lymphomas were of non-Hodgkin's type. All patients presented with a painless unilateral parotid swelling. Most patients had a short history of less than 4 months' duration, of whom 3 presented with a rapidly evolving swelling of less then 1 month's duration. No patient had a background of Sj?gren's disease or any other autoimmune disorders. The commonest finding noted on CT was of a unilateral, single mass of relative soft-tissue homogeneity with poorly defined, indistinct tumour margins. Associated loco-regional lymphadenopathy was identified in 2 cases, 1 clinically and another radiologically; multiple ipsilateral lesions were noted in 2 cases. No cases of contralateral disease were observed. CONCLUSION: Lymphoma has a clinical presentation similar to other neoplasms arising within the parotid gland. A unilateral, non-tender swelling was a universal finding. A history of less than 4 months may suggest the possibility of lymphoma. CT scanning is a useful adjunctive investigation to determine the site and extent of the disease, loco-regional nodal status and contralateral gland and neck status. Multifocality and associated adenopathy are associated with, but not exclusive to, parotid lymphoma. Although poor tumour boundary definition on CT imaging is a strong predictor of malignancy, no pathognomonic finding specific for lymphoma has been identified. The potential diagnosis of parotid lymphoma should be considered in all patients who present with a parotid mass.     

自发性脊柱硬膜外血肿的非典型MRI表现与鉴别诊断

目的 提高对自发性脊柱硬膜外血肿非典型MRI表现的认识.方法 对2000年至2008年来院的10例自发性脊柱硬膜外血肿非典型MRI表现进行分析,男7例,女3例;年龄12--64岁,平均32.1岁.所有病例均无明显的外伤史.常规行矢状位T1WI、T2WI,横轴位TwI,8例行增强扫描.结果 血肿呈梭形、椭圆形,位于脊髓的侧后方或后方的硬膜外腔.血肿发生于颈段5例,胸段3例,胸腰段2例.病灶与脊髓之间有一低信号线状影相隔,尤以T2WI显示最佳.血肿范围多在2～4个椎体,总量约5～10 ml,均值为(6.9±1.8)ml.在T1WI图像上,6例表现为等信号,4例表现为高信号;在T2WI图像上,6例表现为混杂高信号,4例表现为混杂低信号.5例血肿壁边缘轻度强化.6例血肿MRI信号比较典型.4例血肿MRI信号不典型.活动性出血以及血肿因时间而演变是血肿征象不典型的原因.本组4例误诊的原因:(1)活动性出血所致血肿征象不典型;(2)血肿位于狭窄的腔隙内;(3)临床上无外伤史.结论 根据血肿演变的规律,结合起病时间及可能存在活动性出血对血肿MRI信号进行分析,有利于对非典型血肿的诊断和鉴别诊断.