Two types of phantoms were developed with which to evaluate the overall performance of digital subtraction angiography (DSA) systems. A dynamic phantom, called a "fish bone" phantom, consists of polyethylene tubes that simulate blood vessels with various lesions, such as stenoses, ulcers, and aneurysms. With this phantom, washout curves were obtained representing the relationship between iodine content and time. It will be useful for qualitative assessment of DSA images, evaluation of different image-processing schemes, and studies of blood flow analysis. A static phantom, called a "C-D" phantom, can be used for measurement of quantitative contrast-detail (C-D) diagrams and for daily monitoring of DSA systems. This was constructed of tubes of seven different diameters (2.15-0.28 mm) and 14 different concentrations of contrast medium (100%-1.1% Renografin-76 [meglumine and sodium diatrizoate]). The C-D diagrams were determined from an observer performance study using C-D phantom images obtained at four different DSA settings.

Rattenborg, Christen C. M.D.; Reider, Bruce M.D.; Duda, Eugene E. M.D. Author Information

Much interest has recently been focused on the possible role of the endogenous opiates in the perception of pain in humans. Several investigators have examined the levels of these substances in human cerebrospinal fluid (CSF) in attempts to identify the mechanisms by which electrical stimulation of the brain might induce analgesia. Most of these CSF samples were collected at the time of ventriculography or myelography. In the present study, the levels of beta-endorphin in the CSF of 22 patients undergoing myelography were examined before and after the injection of a contrast agent. beta-Endorphin increased an average of 356% (p less than 0.0005) 15 to 20 minutes following the injection of contrast material into the lumbar subarachnoid space. Thus, routine myelography may have a profound effect on the levels of beta-endorphin measured by radioimmunoassay in human CSF, and great care must be taken in interpreting the significance of changes seen in beta-endorphin levels in CSF collected from patients at the time of myelography or ventriculography. The effect of the injection of contrast material on beta-endorphin immunoreactivity must be distinguished from the postulated effects of any analgesia-inducing therapy.

Two types of stereoscopic phantoms were constructed to determine the sensitivity of observers in detecting depth information obtained by means of the magnification stereoscopic technique. One of these, a "plus" phantom, contained perpendicular aluminum wires at the top and bottom of steps of various thicknesses; the observer was asked to identify whether one of the wires was on the top, the bottom, or uncertain in location. The fraction of correct responses versus the height of the step was plotted, indicating the detectability of depth. Fourteen of 20 unselected observers (70%) responded consistently and were considered "good" observers. In general, the greater the stereo shift, the greater the fraction of correct responses. A second phantom, a mesh phantom, contained standard and randomly positioned test wires. The observer was asked to identify the depth position of a test wire with respect to the standard wire if they were in the same plane. It was found that observers can discriminate depth differences of one to two millimeters in magnification stereoscopy, and similar performance for magnification stereoscopic cerebral angiograms is expected.

Four meningiomas were scanned during surgery using a commercially available, real-time sector sonographic scanner. Each lesion was ext remely well defined , and its effects on the surrounding brain were easily characterized by su rround ing edema and displaced ventricles. In one case, sonography demonst rated the nonresect ability of a portion of the tumor because of involvement of the superior sagittal sinus. Th is preliminary experience suggests sonographic imaging may be useful during the resection of meningiomas.

Superior sagittal sinus thrombosis is an often unrecognized clinical condition. This is due to its variable clinical presentation and its association with other serious disease states. The following cases demonstrate that, in the infant, thrombosis of the superior sagittal sinus can be diagnosed quickly and noninvasively by computed tomography (CT). In those clinical situations in which thrombosis of the superior sagittal sinus may occur and neurological changes exist, axial and coronal CT scans may be quite specific in detecting its occurrence.

Examples are presented of the use of a compression balloon to treat trigeminal neuralgia, of a dilating balloon to release a web obstruction of the internal carotid artery, of detachable balloons to seal carotid-cavernous and vertebral-venous fistulas, of a temporary occlusive balloon to aid in thrombogenic treatment of a giant aneurysm, and of a temporary occlusive balloon with double or triple-lumen capacity to assist in angiographic diagnosis and to provide reversible carotid occlusion.

In a preliminary demonstration of cranial intraoperative real-time ultrasound, both supratentorial and posterior fossa scans displayed the pertinent anatomy. A grade III astrocytoma was visualized on the supratentorial scan as well. Ultrasound may be valuable for surgical planning and biopsy procedures because of its reliable depiction of intracranial anatomy and ease of use.

A retrospective and prospective analysis of cerebral arteriograms in 28 patients with intracerebral arteriovenous malformation (AVM) was undertaken to identify those parameters that predict the efficacy of small silicone particle embolization as a method of treatment. It was noted that when the number and caliber of the arterial feeding vessels were greater than the number and caliber of the draining veins the embolization was successful (15 of 16 patients). On the contrary, when the number and caliber of the draining veins exceeded that of the arteries the embolization failed (seven of seven patients). In four of five patients with nearly equal ratios, the embolization reduced the flow but not the size of the malformation.

Previous experimental and clinical observations suggest that radiation is a causative factor in the development of meningiomas. We report a rare case of three spinal meningiomas in a patient who had prior irradiation in the spinal region. The myelographic technique to evaluate multiple spinal canal tumors is outlined.

Subacute sclerosing panencephalitis is a progressive, frequently fatal slow virus infection of the brain attacking children and young adults and caused by measles virus. Computed tomography (CT) of the brain in 15 patients with this disease was normal in seven and abnormal in eight. CT demonstrated varying degrees of cortical atrophy associated with focal and multifocal low density lesions of the white matter. Two cases demonstrated low density lesions of the caudate nuclei. The CT lesions were seen in chronic cases and reflect the gliosis and atrophy that occur in this disease. Differential diagnoses include other viral infections and demyelinating and dysmyelinating diseases. Diagnostic laboratory evaluation includes serum and cerebrospinal fluid titers for measles antibodies, cerebrospinal fluid protein electrophoresis, electroencephalography, and cranial CT.

Twenty-one patients with grade III or IV astrocytomas were assigned randomly to receive either BCNU alone or BCNU and VM-26 after surgery and radiation therapy. Patients surviving radiation therapy and receiving single-agent chemotherapy had a median survival of 14 months while those receiving combination chemotherapy had a median survival of 22 months (P greater than 0.05). None of the patients who failed BCNU-only therapy responded to VM-26. Performance status was not affected by either regimen. Computerized tomographic scanning of the brain was useful only in confirming tumor progression. Two patients died from BCNU-related interstitial pulmonary fibrosis.

Three patients are reported who developed delayed intracerebral hematomas following closed head injuries. Two patients showed hematomas within 24 hours after a normal computerized tomogram. All three were treated surgically, and two had good results.

To identity those patients with hydrocephalus as a basis for their presenile dementia it is suggested that such patients be screened non-invasively by CT scan. If there is ventricular dilatation and small cortical sulci, intracranial pressure should be monitored for 48 hours to detect `B' waves. Patients with significant `B' waves (10 mmHg) for at least two hours in the day might benefit from a shunt.

Computed tomograms (CT) demonstrated symmetrical low-density lesions in the white matter of the posterior portion of the cerebral hemispheres in a 9-year-old boy with adrenoleukodystrophy (Schilder's disease). Biopsy of the brain in an area that appeared normal on the CT scan showed profound loss of myelinated fibers and oligodendroglia; the white matter had been replaced by a rather loose acellular stroma consisting of astroglial cells and blood vessels.