Citations

Abstract Twenty surgically verified pituitary adenomas were imaged in a systematic comparative fashion with high field strength magnetic resonance imaging (MRI) and computed tomography (CT) before operation. The study group included 11 microadenomas, 4 macroadenomas, 2 recurrent microadenomas, and 3 recurrent macroadenomas. The MRI and CT examinations were evaluated for lesion detection, pituitary stalk displacement, cavernous sinus displacement or invasion, hemorrhage, cystic degeneration within the adenoma, bony erosion, detection of suprasellar extension, and displacement of suprasellar structures. T1 and T2 relaxation characteristics of the adenomas were evaluated on MRI examinations, and contrast enhancement characteristics were evaluated on CT examinations. MRI was superior to CT for detecting the extrasellar extent of tumor. Within the sella turcica, MRI and CT were equivalent with regard to lesion detection, except for 1 patient in whom CT was able to detect a surgically confirmed 3-mm microadenoma that was not visualized on the MRI examination. (Neurosurgery 22:380-385, 1988)

Abstract Six patients with juvenile pilocytic astrocytomas of the thalamus or basal ganglia underwent seven computer-assisted stereotactic laser craniotomies with complete or nearly complete removal of the tumor in all cases. The tumor was located in the right basal ganglia in one patient, the left basal ganglia in one patient, and the left thalamus in four patients. Postoperative assessment of the completeness of tumor removal was confirmed by contrast-enhanced computed tomographic scanning within the first 2 weeks after operation. None of the patients was neurologically worse after the procedure, and five were improved. The duration of follow-up ranged from 6 months to 3.5 years. In this group of patients, the computer-assisted, stereotactically guided resection of these deeply located, benign tumors was accomplished with no morbidity or mortality.

Abstract This report describes a computed tomography-based computer-assisted stereotactic technique for performing 3rd ventriculostomy. The procedure has been performed on seven patients with acquired obstructive hydrocephalus of various etiologies. None of these patients have yet required shunting. (18:791–794, 1986)

Abstract We have developed a computer-resident stereotactic atlas of the human brain that quantitatively defines subcortical structures within anatomical landmarks detected on obliquely reconstructed computed tomography (CT) slices. Horizontal stereotactic atlas sections can be stretched and contracted by polar transformation and labeled by a computer to fit within these CT scan-defined landmarks. The stereotactic coordinates of any substructure on the atlas-labeled CT slice may then be calculated by the computer and expressed in mechanical adjustments on a stereotactic surgical frame located in the operating room. We demonsrate the use of this method in the stereotactic treatment of movement disorders as an augmentation to conventional ventriculography and microelectrode recording.

Abstract Myelography and myelography assisted with computed tomography have been the most commonly used radiographic methods in the study of syringomyelia. These studies have never been entirely reliable in demonstrating the syrinx cavity and its relationship to other intracranial structures. During the 1st year of operation of the magnetic resonance imaging facility, the syringomyelic cavity was demonstrated in 15 patients who all had typical clinical signs and symptoms associated with syringomyelia. Nine cases were syringomyelia with Chiari malformation. One case showed additional hydrocephalus. Four cases were idiopathic, and 1 case was remotely posttraumatic. Magnetic resonance imaging, although it is in its infancy, already promises to be the most important radiographic technique for syringomyelia because it provides an anatomically truthful visualization of the sagittal plane of the cervical cord and can demonstrate the syrinx cavity and its relationship with the cerebellar tonsils, the 4th ventricle, and other related structures.

Abstract Spontaneous cerebrospinal fluid (CSF) rhinorrhea, occurring in the absence of recent trauma, is a distinct clinical entity that can be difficult to diagnose and treat. The case records of 28 patients with this entity were reviewed retrospectively. Pertinent historical data and the results of radiographic evaluation are discussed. The patients were classified into one of three major etiological categories: congenital anomaly, delayed posttraumatic, and tumor groups. The fistulas causing the rhinorrhea were approached extracranially or intracranially, depending on the suspected cause and location. A cure was obtained in 22 of the 27 patients surgically treated (81%). Seventeen patients were cured by a single operation, 5 were cured after multiple operations, and 5 continued to leak despite surgical treatment. Three of the 5 patients who were surgical failures had intracranial tumors, and 2 of them died from complications of persistent fistulas. With the use of a multidisciplinary team approach, an extracranial operation (transethmoidal or transsphenoidal) to repair a spontaneous CSF leak offers a high success rate and is associated with minimal morbidity in appropriately selected patients.

Abstract A simple and reproducible method of quantitating the amount of hematoporphyrin derivative by fluorescence microscopy in biopsies of tumors from patients undergoing photoradiation therapy is presented, substantiated by laboratory studies of experimental central nervous system tumors and normal rat tissues. The literature regarding the quantitation of hematoporphyrin is reviewed, and implications of this study for the future application of photoradiation therapy and the design of laboratory studies are discussed.

Abstract A 6-year retrospective analysis of incidental intracranial aneurysm surgery was conducted at 12 medical centers (1975-1981). The surgical facilities and techniques were comparable at the institutions surveyed. From a total of 1671 aneurysms operated upon, 119 in 107 patients were unruptured and were discovered incidentally. Among these 107 patients, there was no operative mortality. Operative morbidity occurred in 7 cases (6.5%). Surgical treatment of large aneurysms in less accessible locations incurred the greatest operative morbidity. Presenting symptoms of cerebral ischemia seemed to be associated with increased operative morbidity, whereas repair of aneurysms incidental to other ruptured aneurysms had a uniformly low morbidity. These surgical results compare favorably with the risks of hemorrhage from unruptured intracranial aneurysms as defined by recent reports. The low morbidity without mortality supports a recommendation for surgical management of incidental aneurysms in the anterior circulation at centers equipped for modern aneurysm surgery.

Abstract Hematoporphyrin derivative accumulates in malignant brain tumors and, when activated by light, can produce a cytotoxic reaction. A system for utilizing this concept in the treatment of human malignant brain tumors has been developed and tested in a small series of patients. No significant adverse reactions have occurred, and further development and research are planned.

Abstract A case of intraventricular tension pneumocephalus occurring as a complication of paranasal sinus surgery is presented. The pathophysiology of tension pneumocephalus is discussed and emphasis is placed on the potentially life-threatening increase in intracranial pressure that occurs. Tension pneumocephalus requires prompt diagnosis and treatment.