Brain stem infarction due to chiropractic manipulation of the cervical spine

A case of brain stem infarction after chiropractic manipulation of the cervical spine is presented. Proposed mechanisms and sites of possible arterial injury are discussed. A diagnosis of vertebral artery occlusion was made using conventional brachial angiography. Digital intravenous angiography, a relatively new and less invasive vascular imaging technique which was used as an adjunct for evaluating the remainder of the cervicocephalic vessels, documented the vertebral occlusion. Chiropractic manipulation, which is increasing in popularity, may be a cause of potentially devastating neurologic disease.

The tethered spinal cord: diagnosis by high-resolution real-time ultrasound

High-resolution real-time ultrasonography of the lumbosacral spine was performed in 10 control patients and in six patients with suspected spinal dysraphism. The spinal cord was readily visualized in both groups. Lack of ossification of the posterior arch of the spine in normal infants and the presence of a bony defect in patients with spina bifida permit sonographic investigation of the spinal canal and its contents. It is concluded that the diagnosis of spinal cord tethering can be established rapidly by high-resolution real-time ultrasonography, which may be used in screening patients with suspected occult spinal dysraphism.

Brain stem infarction due to chiropractic manipulation of the cervical spine

A case of brain stem infarction after chiropractic manipulation of the cervical spine is presented. Proposed mechanisms and sites of possible arterial injury are discussed. A diagnosis of vertebral artery occlusion was made using conventional brachial angiography. Digital intravenous angiography, a relatively new and less invasive vascular imaging technique which was used as an adjunct for evaluating the remainder of the cervicocephalic vessels, documented the vertebral occlusion. Chiropractic manipulation, which is increasing in popularity, may be a cause of potentially devastating neurologic disease.

Giant intracranial aneurysm presenting as a posterior fossa mass

A patient with signs of brainstem compression and hydrocephalus is reported. The clinical picture suggested a posterior fossa neoplasm. Computed tomography, however, proved highly accurate in making the diagnosis of a giant, partially thrombosed vertebrobasilar aneurysm. The radiographic appearance of this entity is summarized and pathologic correlation is offered.

Intravenous digital subtraction angiography in the investigation of intracranial disease

Eighty-six patients who presented with a variety of intracranial lesions were examined with intravenous digital subtraction angiography (IV-DSA). A grading system was used to evaluate the ability of IV-DSA to answer specific diagnostic questions regarding intracranial tumors, vasospasm following subarachnoid hemorrhage, lesions of the sella, dural sinus occlusion, and post-therapeutic embolization. Eighty-four per cent of the examinations provided clinically useful information. In 15% of the cases limited but useful information was obtained; only 1% of the examinations provided no useful information. We conclude that IV-DSA can routinely provide useful information in the evaluation of the variety of intracranial lesions described above.

Comparison of radiographic quality and adverse reactions in myelography with iopamidol and metrizamide

A randomized double-blind study was conducted to compare the radiographic quality and adverse reactions in myelography of the two nonionic water-soluble contrast media, iopamidol and metrizamide. A total of 46 myelograms were obtained, 28 with iopamidol and 18 with metrizamide. Untoward reactions consisted of nausea, headaches, back and leg pain, neuropsychiatric findings, and urinary retention. Iopamidol caused no reactions in 20 of the 28 cases, while metrizamide caused no reactions in only three of 18 cases. Film quality evaluation showed 22 of the 28 studies with iopamidol were judged excellent, whereas only 11 of the 18 metrizamide studies were judged excellent. The results of this study suggest that iopamidol produces better quality studies with fewer and milder adverse reactions than metrizamide.

Vasospasm secondary to ruptured aneurysm: assessment by digital intravenous angiography

Digital intravenous angiography was used for the documentation and evaluation of cerebral vasospasm secondary to acute ruptured aneurysm. Attenuation of vessel caliber and/or generalized poor visualization of intracranial arteries and prolongation of circulation time were observed in seven patients with the acute clinical diagnosis of cerebral vasospasm. Posttreatment intravenous angiography demonstrated improvement in both arterial caliber and circulation time in six patients who responded to medical therapy for vasospasm. Digital intravenous angiography allowed repeat investigations of the intracranial vasculature safely and quickly without undue risk to the critically ill patient.

Giant intracranial aneurysms: rapid sequential computed tomography

Giant intracranial aneurysms often present as mass lesions rather than with subarachnoid hemorrhage. Routine computed tomographic (CT) scans with contrast material will generally detect them, but erroneous diagnosis of basal meningioma is possible. Rapid sequential scanning (dynamic CT) after bolus injection of 40 ml of Renografin-76 can conclusively demonstrate an intracranial aneurysm, differentiating it from other lesions by transit-time analysis of the passage of contrast medium. In five patients, the dynamics of contrast bolus transit in aneurysms were consistently different from the dynamics in pituitary tumors, craniopharyngiomas, and meningiomas, thereby allowing a specific diagnosis. Dynamic CT was also useful after treatment of the aneurysms by carotid artery ligation and may be used as an alternative to angiographic evaluation in determining luminal patency or thrombosis.

Small acoustic neuromas: detection by high resolution gas CT cisternography

Experience with 81 gas computed tomography (CT) cisternography procedures in 79 patients in searching for acoustic neuroma is reported. Twenty-one tumors, four exclusively intracanalicular, were demonstrated after standard contrast-enhanced CT was negative. Fifty-five examinations were negative; four were inconclusive. The high resolution scanner with digital localization and reconstruction zoom capability greatly improved image detail. In nine of the 12 normal patients examined with it, the intracanalicular bundle was demonstrated. Substitution of carbon dioxide for air greatly reduced the morbidity of acute post-spinal tap headache. The procedure takes 30--45 min and can be performed on an outpatient basis. It is recommended as the procedure of choice when standard CT is negative in subjects clinically suspected of having acoustic neuroma.

Dynamic CT scanning for visualization of the parasellar carotid arteries

Evaluation of patients before transsphenoidal hypophysectomy for large intrasellar mass lesions has required bilateral internal carotid artery angiography. Using intravenous injection of contrast medium, a method has been developed to visualize the parasellar carotid arteries with rapid sequence sequential computed tomographic scanning. In 18 patients, the cavernous segments of the internal carotid arteries were well seen in 27 of 28 instances with technically complete examinations. The vascularity of the mass lesions and vascular encasement was also demonstrated.

The value of dynamic scanning

Dynamic CT is a proven alternative to angiography in the assessment of parasellar lesions. Characteristics of the tumor, such as vascularity or cystic regeneration, are easily demonstrated. Dynamic CT is able to diagnose conclusively an intracranial aneurysm and to follow the therapeutic course after ligation of the carotid artery. The application of dynamic CT to cerebrovascular disease is limited by the lack of subsecond sequencing in fragmentation scans. Its importance in documenting the patency of the cervical internal carotid artery that appears to be occluded angiographically cannot be overstressed.

Dense cystic craniopharyngiomas

Characteristic computed tomographic (CT) findings of craniopharyngioma include calcification, contrast enhancement, and cyst formation. Sharp margins associated with a hypodense centrum usually characterize the CT appearance of a cystic tumor. The appearance of "dense" cysts in craniopharyngiomas has not been emphasized. Four cases of craniopharyngiomas with isodense to hyperdense cysts are reported. Comparative biochemical and in vitro CT analysis of cyst aspirates taken from these lesions demonstrate that high intracystic protein concentration accounts for the greater part of the hyperdensity. Various mechanisms for intracystic protein accumulation are discussed. Lesion characteristics, and not necessarily attenuation coefficients, are stressed in differentiating "dense" cystic from solid craniopharyngiomas.

Computed tomography in the diagnosis of eosinophilic granuloma

The clinical, radiographic, and computed tomographic (CT) findings in three proven cases of eosinophilic granuloma are presented. Because eosinophilic granuloma has typical appearance on CT, this method is more useful than plain film tomography in diagnosing this lesion.

Neuroradiologic diagnosis of subdural empyema and CT limitations

Five cases of subdural empyema are described. Two of the cases eluded a definitive computed tomography (CT) diagnosis despite classical clinical background. Extracerebral collection with definitive border enhancement was seen in the other three cases. Mass effect, present in all five cases, was related to the extracerebral collection in three cases and diffuse cerebral edema and/or infarction in two. Angiography in four cases initially demonstrated an extracerebral collection in three and inflammatory angiospasm in two. Repeat angiography demonstrated an extracerebral collection in the fourth case. In the proper clinical setting subdural empyema should be considered even in the absence of an extracerebral collection when mass effect or an infarction pattern is seen on CT. Angiography may be diagnostic in such cases. Hopefully, newer techniques will further the diagnostic efficacy of CT in this disease.

Air-CT cisternography and canalography for small acoustic neuromas

Disenchantment with the limitations, and in some cases the morbidity, of currently used radiologic techniques for the demonstration or exclusion of small acoustic neuromas prompted development of an examination using small amounts of intrathecal air and computed tomography (CT). A prospective study was designed to evaluate air CT cisternography/canalography, wherein patients with the clinical symptoms of acoustic neuroma but with negative enhanced CT, were evaluated by metrizamide CT cisternography followed by air CT cisternography/canalography. Pantopaque cisternography was then performed as a control procedure. Four patients had surgically proven tumors. In 13 others, accumulated evidence indicated no tumors were present. Results suggest that air-CT cisternography is superior to all other diagnostic methods in defining small acoustic neuromas, and may exclude an intracanalicular lesion without the potential hazards of Pantopaque cisternography or high concentration metrizamide tomocisternography. With air-CT cisternography, there were no errors in this series.

Correlation between computed tomography and intracranial pressure monitoring in acute head trauma patients

A preliminary retrospective correlation between computed tomographic scans and intracranial pressure (ICP) monitored was performed for 21 patients. No patient with a normal CT scan had elevated ICP. The lowest correlation was noted with slit ventricles; the highest, with dilatation of the contralateral temporal horn.

Correlation of computed tomographic, angiographic, and neuropathological changes in giant cerebral aneurysms

Giant aneurysms involving or adjacent to the circle of Willis exhibit three CT patterns: nonthrombotic, partially thrombotic, and completely thrombotic. Partially thrombotic aneurysms have the most specific pattern, consisting of a "target" configuration on the post-contrast scan. Ring calcification of the wall or mural thrombus is frequently observed in partially or completely thrombotic aneurysms. Calcification is not seen in nonthrombotic lesions. Angiographic and neuropathological findings are correlated with the CT findings.

Computed tomography of arachnoid cysts

The typical CT appearance of intracranial arachnoid cysts may obviate additional neuroradiological procedures. Ventriculography using water-soluble contrast media may differentiate a suprasellar arachnoid cyst from a dilated third ventricle. Twelve cases are presented.

The base view in vertebral angiography. An aid in the diagnosis of extraaxial cerebellopontine angle tumors

Though the advent of computed tomography has improved the detection of posterior fossa lesions, there are times when it can not be used to differentiate between an intra- and extraaxial lesion, particularly when the mass is anteriorly located. Base view angiography can be used to make this distinction, accurately localize the lesion, and demonstrate involvement or compression of vital adjoining structures.