Efficacy of magnetic resonance angiography in the evaluation of vascular malformations of the hand.

Conventional arteriography has been the accepted standard technique for demonstrating the anatomic details in vascular malformations of the hand. The technique of magnetic resonance angiography provides detailed anatomy for vascular anomalies of the hand without the use of an invasive technique or contrast enhancement. When magnetic resonance angiography is combined with magnetic resonance imaging, the extent of the lesion with respect to the surrounding tissues and the flow characteristics of the lesion can be determined noninvasively. In our institution, magnetic resonance angiography has replaced conventional arteriography as the technique of choice for the evaluation of these lesions. This report evaluates the efficacy of magnetic resonance imaging/ magnetic resonance angiography in the management of vascular malformations of the hand. Ten consecutive patients over 30 months (median age 37 years) underwent magnetic resonance imaging/magnetic resonance angiography evaluation after the clinical diagnosis of a vascular malformation of the hand was made. Four patients in the group had conventional arteriography performed before referral. Magnetic resonance imaging/magnetic resonance angiography clearly defined the anatomic extent of the lesion, its relationship to surrounding tissues, and the flow characteristics in each patient. In the four patients in whom conventional arteriography had been performed, the magnetic resonance angiography findings matched the arteriographic findings. On the basis of the magnetic resonance imaging/magnetic resonance angiography findings, six patients were treated nonoperatively with compressive garments and four patients had operative treatment (resection of lesion n = 2, digital ray resection n = 2). In this series, magnetic resonance imaging/magnetic resonance angiography was efficacious in the management of vascular malformations of the hand. This technique provides detailed images of both the arterial and venous components of the lesions without the requirements of contrast enhancement, ionizing radiation, or an invasive procedure. Furthermore, the resectability can be determined based on the extent of involvement and the flow characteristics.

Bleeding patterns in ruptured posterior fossa aneurysms: a CT study.

Computed tomography of the brains in 20 patients with acute rupture of posterior fossa aneurysms was reviewed and analyzed retrospectively. Findings were compared with those from 44 cases described in the literature and with the findings in ruptured supratentorial aneurysms. Extravasated blood was observed in 19 of 20 patients (95%); intraventricular hemorrhage (IVH) in 17 of 20 (85%); and subarachnoid hemorrhage (SAH) in 13 of 20 (65%). These values were significantly higher than those previously reported and suggest that, during the acute phase of rupture, extravasated blood may be detected with the same frequency in either infratentorial or supratentorial ruptured aneurysms. Subarachnoid hemorrhage was accompanied by IVH, prominent in the fourth ventricle and without intraparenchymal hematoma, in 11 patients (55%). This pattern is highly suggestive of ruptured posterior fossa aneurysms. Intraventricular hemorrhage without SAH was noted in five patients (25%) and specifically represented ruptured posterior inferior cerebellar artery aneurysms. Subarachnoid hemorrhage without IVH was noted in only two patients (10%).

Magnetic resonance imaging of a high cervical intradural lipoma.

A case of intradural spinal lipoma, rarely seen in the high cervical region, is described. Extension into the posterior fossa is not infrequent with these rare tumors. Magnetic resonance imaging clearly showed the longitudinal dimension of the tumor as well as the infiltrative extension into the spinal cord without any invasive procedure.

High signal intensity of both putamina in patients with HIV infection.

We report two patients with HIV infection whose MR imaging showed abnormal high signal intensity confined to both putamina on T2-weighted spin echo (SE) images. We assume that they may represent the early manifestations of HIV encephalitis.

Magnetic resonance imaging of limbic encephalitis.

In two patients with limbic encephalitis serial magnetic resonance (MR) imaging showed evolution of abnormal high-signal intensity in both hippocampal formations on T2-weighted images.

Vascular metastatic lesions of the spine: preoperative embolization.

Preoperative embolization of vascular metastatic tumors of the spine, particularly carcinomas of renal and thyroid origin, is an adjuvant technique that significantly decreases the intraoperative blood loss and resultant surgical morbidity. Surgical decompression was achieved in 24 spinal vascular metastatic lesions, 20 of which were treated with preoperative embolization and four of which were not. The embolic materials used were gelatin sponge, polyvinyl alcohol foams, and metallic coils. In patients who underwent adequate embolization, an average of 1,850 mL of estimated blood loss was reported; in those who underwent inadequate or no embolization, greater than 3,500 mL of estimated blood loss occurred. When gelatin sponge is used, surgery should be performed within 24 hours to prevent preoperative recanalization.

Pituitary hyposecretion and hypersecretion produced by a Rathke's cleft cyst presenting as a noncystic hypothalamic mass.

A 53-year-old man presented with polydipsia, polyuria, lightheadedness on standing, and syncope. Visual field deficits suggesting left optic tract compression and pituitary dysfunction consisting of diabetes insipidus, hyperprolactinemia, and anterior pituitary insufficiency were diagnosed. On the computed tomography scan, an isodense, ring-enhancing, parasellar mass was localized primarily in the suprasellar region and also extended into the sella. It was believed that the pituitary hormone hypersecretion and hyposecretion were due to hypothalamic dysfunction from the mass which was initially believed to be a craniopharyngioma. At surgery a Rathke's cleft cyst was resected. The unusual presentation of this Rathke's cleft cyst presenting as a hypothalamic lesion is discussed.

Carcinoid tumor with intradural spinal metastases.

A case of spinal intradural metastasis from a carcinoid tumor is reported. The case is of interest due to the rarity of central nervous system involvement by these tumors and the long latency period of the patient's presentation.

Early sequelae of gunshot wounds to the spine: radiologic diagnosis.

During a 6-month period, 11 consecutive patients who had delayed neurologic deterioration after sustaining a gunshot wound to the spine were prospectively evaluated clinically, radiologically, and surgically. The patients had dysesthetic burning pain in an anesthetic area, hyperhidrosis, flexor spasm, and additional motor deficit above the level of cord injury 2-22 weeks after injury. Radiologic evaluation consisted of plain radiography of the spine and metrizamide myelography followed by computed tomography. A syringomyelic cavity was found in seven patients, an arachnoid cyst in three, and osteomyelitis in one. Seven of these patients also had cord atrophy. Postoperatively, dysesthetic pain was relieved in all the patients. There was no recurrence during a 2-year follow-up. These results emphasize the need for immediate radiologic investigation in patients with gunshot wounds of the spine who have further deterioration superimposed on their initial deficit.

Traumatic carotid-cavernous fistula.

Carotid-cavernous fistulas are uncommon, although not rare, complications of trauma to the base of the skull; they may result in cranial nerve palsies, blindness, and occasionally in devastating subarachnoid hemorrhage. We have presented a case of carotid-cavernous fistula in a 17-year-old boy, treated successfully with balloon embolization. Although surgical treatment was advocated in the past, the low morbidity and high success rate of percutaneous balloon embolization currently make this the procedure of choice.

Pure thoracolumbar facet dislocation: clinical features and CT appearance.

The use of computed tomography (CT) in demonstrating pure dislocations of the thoracolumbar facets and in predicting the prognosis of this injury was evaluated and compared with radiography retrospectively. The records of 29 patients with pure thoracolumbar bilateral facet dislocation who were admitted to the trauma unit over a 4-year period were reviewed. Twenty-two patients (76%) had a complete neurologic loss that remained complete following immediate surgical stabilization; five (17%) had an incomplete neurologic loss, and two (7%) were normal neurologically. Plain radiographs of the spine, including anteroposterior and lateral views, documented the level and type of fracture but failed to depict the full extent of bony ad soft-tissue injuries. CT provided essential additional information, particularly regarding the status of the posterior elements of the vertebrae and the adequacy of the spinal canal. Pure thoracolumbar facet dislocations have a characteristic appearance on axial CT scans. Sagittal reformation through CT is essential in the evaluation of this type of spinal injury.

Osteoblastoma of the temporal bone: CT findings.

A case of recurrent benign osteoblastoma of the temporal bone is presented with discussion of the clinical, radiological, and pathological findings. Previously reported cases of osteoblastoma of the temporal bone are briefly reviewed.

Imaging modalities of craniosynostosis with surgical and pathological correlation.

Premature fusion of the sutures of the skull has been extensively analyzed and several diagnostic imaging modalities have been proposed. Radiographic, scintigraphic and computed tomographic features of craniosynostosis have been reported. This study was initiated (a) to determine the value and accuracy of plain skull radiography, skull scintigraphy and cranial CT; and (b) to determine the optimal imaging modality for the evaluation of a clinically suspected craniosynostosis. The study is based on 36 patients with clinical suspicion of craniosynostosis who underwent craniectomy and cranioplasty. One hundred and three sutures were pathologically and/or surgically evaluated. The overall accuracy rate for skull radiography was 89%, skull scintigraphy, 66%, and cranial CT, 94%. Routine skull series are adequate in the majority of cases of craniosynostosis. Skull scintigraphy is less accurate, more costly, and has a limited role in the evaluation of craniosynostosis. Cranial CT should be reserved for those cases in which the findings in the routine skull series are not clearly positive or negative, or in cases of more complex craniofacial anomalies.