[Differential diagnosis of Graves' disease and orbital pseudotumor: CT findings (author's transl)].

CT scans of 25 clinically typical cases of Graves' disease and 15 cases of orbital pseudotumor (idiopathic orbital inflammation) are analyzed and differential diagnostic criteria evaluated. The CT-findings overlap and are best viewed as a continuous spectrum at both ends of which characteristic patterns can be identified. Massive swelling of ocular muscles, involving of several muscles, usually without density changes of the orbital fat, are diagnostic for Graves' disease.

Radiography of trigeminal neuralgia and hemifacial spasm.

Radiographic findings in 68 patients with trigeminal neuralgia and 24 patients with hemifacial spasm are reviewed. The relative value of various radiographic diagnostic procedures is discussed. Trigeminal neuralgia and hemifacial spasm are usually caused by vascular compression of the trigeminal root entry zone and facial nerve exit zone respectively.

Traumatic dislocation of the atlanto-occipital articulation (AOA) with short-term survival. With a radiographic method of measuring the AOA.

Three patients with traumatic atlanto-occipital articulation (AOA) dislocation are presented, and an additional 10 well documented cases are reviewed from the literature. Medulla oblongata and/or spinal cord deficits, and evidence of cranial nerve injuries were noted in eight patients. Angiographic evidence of vertebral occlusion or narrowing was demonstrated in four patients.

Meningiomatous changes in the optic canan: a polytomographic study.

Eleven patients who had unilateral insidious compression of the optic nerve but exhibited no detectable abnormality on plain skull radiographs or non-tomographic views of the optic canal were studied. Paracanalicular meningioma was proved surgically in 10. Complex-motion tomography demonstrated characteristic alterations in the bone forming the optic canal in all cases.

Prolactin-secreting pituitary adenomas: correlation of radiographic and surgical findings.

The preoperative hypocycloidal sellar tomograms, angiograms, and pneumoencephalograms of 100 patients being evaluated for prolactin-secreting pituitary adenomas were reviewed and the results correlated with surgical findings at transsphenoidal exploration. The majority (53%) of tumors encountered were microadenomas. Although sellar volume was normal in 72%, sellar shape on tomography was abnormal in 96%; the location of the tumor within the sella could be predicted by means of tomography alone in 88%.

Indications for angiography in the preoperative evaluation of patients with prolactin-secreting pituitary adenomas.

The preoperative angiograms of 100 patients subsequently undergoing transsphenoidal exploration for prolactin-secreting pituitary adenomas were reviewed in order to assess both the risk of this study and its yield of useful diagnostic information. In these patients with documented hyperprolactinemia, no vascular anomalies contraindicating a transsphenoidal approach were detected. Tumor blush was evident only in large tumors.

CT-evaluation of extraocular muscles - anatomic-CT-correlations.

CT evaluation of the extraocular muscles is unsatisfactory in the commonly used axial and coronal planes. Based on the analysis of anatomic and computed tomographic sections and reformations in various planes, optimal examination techniques for the evaluation of the extraocular muscles are discussed. Their anatomic relationship to other clinically and surgically important orbital structures is shown.

[Ct-criteria of orbital hemangiomas and their importance in differential diagnosis of intraconal tumors (author's transl)].

CT-scans of 29 histologically proven cavernous hemangiomas were evaluated with respect to their location, shape, delineation from surrounding tissue, contrast-enhancement, and secondary changes of the bony orbit. Whenever a round or oval tumor, located in the outer upper muscle cone, sharply delineated from surrounding tissue, unattached to optic nerve and ocular muscles, spares a small triangular space in the orbital apex, it is in all probability a cavernous hemangioma. Evaluation of the tumors shape and its separation from surrounding tissues requires imaging in multiple sections in two planes oriented, if possible, at right angles.

The angiographic features of extraabdominal desmoid tumors.

Extraabdominal desmoid tumors are nonencapsulated locally invasive neoplasms of fibrous tissue. The angiographic features include arterial stretching, neovascularity, and tumor staining (4 of 6 cases in this series). Although benign, these tumors are difficult to cure because they tend to recur locally.

Metrizamide and radionuclide cisternography in communicating hydrocephalus.

Simultaneous 111In-DPTA and metrizamide CT cisternography correlated closely in the qualitative imaging of cerebrospinal fluid (CSF) dynamics in 9 normal patients and in 11 patients thought to have communicating hydrocephalus. CSF clearance of both tracers was similar; significant absorption occurred in the spinal dural sac. Although delayed elevated serum iodine levels correlated highly with abnormal persistent ventricular penetration (detection at 48 hours), these levels cannot be used to predict abnormal ventricular stasis.

Quantitative aspects of contrast enhancement in cranial computed tomography.

The temporal relationship of blood iodine levels to tumor enhancement in cranial computed tomography was studied in a series of patients. Both the bolus and biphasic techniques were evaluated. Peak tumor intensity may not develop immediately, but may be more pronounced on a 20-minute scan.

Coronal computed tomography: indications and accuracy.

The application of wide aperture scanners to neuroradiology permits improved anatomic definition and localization of intracranial and intraorbital lesions. Coronal scans are most useful in demonstrating lesions of the skull base and apex, distinguishing between infra- and supratentorial lesions, and in determining if a lesion is intra- or extraaxial. Limitations of coronal scans include discomfort in positioning, high spatial frequency artifacts, and additional radiation exposure.

Optimal contrast dosage in cranial computed tomography.

Comparison of different contrast dosages in adult patients with malignant gliomas studied by computed tomography indicates that 28-42 g of iodine is required for clinically diagnostic results. This can be translated into a 10 min iodine blood level of 100 mg/100 ml. Contrast doses in the range of 14 g of iodine are not satisfactory.

Radiologic assessment of pituitary microadenomas.

Radiographs of 146 patients who had a pituitary adenoma removed by the transsphenoidal approach were reviewed. The area and volume of the sella were measured in all the patients. In 73 patients the sella had a normal size and appearance as shown on routine lateral and frontal radiographs.

Computed tomography in the follow-up of medulloblastomas and ependymomas.

The course of 36 patients with medulloblastoma and ependymoma was evaluated prospectively by clinical examination, radionuclide (RN) studies and computed tomography (CT). Seventeen of the 36 patients (47%) had tumor recurrence. Twelve (41%) of the 29 patients with medulloblastoma had recurrent tumors of which 7 of 12 (58%) were at the primary site and 2 of 12 (17%) were within the ventricles while 10 of 12 (83%) were in the subarachnoid space.

Comparative efficacy of contrast agents in computed tomography scanning of the brain.

Various contrast agents with either sodium or meglumine cations and iothalamate and diatrizoate anions are compared in a series of patients with malignant gliomas. There is no difference in the ability of these agents to enhance tumors in cranial computed tomography.

Extra-axial posterior fossa lesions simulating intra-axial lesions on computed tomography.

Differentiation of extra- from intra-axial posterior fossa lesions is sometimes not possible on computed tomography. Six cases are presented wherein the lesion appeared to be intra-axial on computed tomograms yet angiographically and surgically proved to be extra-axial. False localization on computed tomography occurs with slowly growing masses which burrow into brain parenchyma.

[Internal carotid artery supply of juvenile angiofibromas (author's transl)].

Twelve juvenile angiofibromas of the paranasal sinuses are described which were partly supplied by branches of the internal carotid artery. Five vessels were found to be involved; with increasing frequency they were: the middle cerebral artery, the dorsal meningeal artery, the ethmoidal arteries, the artery of the inferior cavernous sinus and the artery of the pterigoid canal. Intracranial extension of tumour occurred only once, but the paranasal sinuses were involved in all cases.

A fatal brain injury caused by a needlefish.

A traumatic internal carotid-cavernous sinus fistula due to a penetrating injury caused by a needlefish is described.

Computed tomography in detecting calvarial metastases: a comparison with skull radiography and radionuclide scanning.

A clinical study comparing the relative sensitivities of computed tomography, skull radiography, and radionuclide scanning in the detection of skull metastases indicated that CT was the least sensitive of these three modalities. CT could however detect a majority of lesions if scans were viewed at appropriate window settings. Phantom studies showed that the limitations of CT can be related to limited spatial resolution, the density of the lesions, partial volume averaging, and plane of section.

Computed tomographic brain scanning in intraparenchymal pyogenic abscesses.

Retrospective analysis of 25 pyogenic brain abcesses diagnosed by computed tomography (CT) revealed relatively specific morphologic characteristics of these infections. The ability to obtain an early accurate diagnosis resulted in a dramatic decrease in patient morbidity and mortality. Repeated examinations by CT permitted close monitoring of the response of the abscess to antibiotic therapy.