Endovascular treatment of traumatic arterio-venous fistulas of the vertebral artery.

Cervical vertebral artery fistulas are rare arteriovenous malformations between the vertebral artery and veins of the neighbourhood. The etiology of the fistulas may be traumatic or spontaneous. Management and the results in two patients with large arterio-venous fistulas of the cervical vertebral artery with severe deterioration of spinal function by using the detachable balloon technique are discussed. Complete angiographic and clinical cure was achieved in both patients and no complications related to the embolization procedure occurred. The detachable balloon technique is an effective method for selective occlusion of the fistula. Good radiographic monitoring facilities are required to make endovascular procedures effective and safe.

Neurosurgical management of cerebellar hemorrhage.

Controversy remains concerning the management of patients with cerebellar hemorrhage. In this study the records of 42 patients were reviewed. In 60% of them the signs of brainstem compression and upward transtentorial herniation were found. The level of consciousness was found to be consistent with the radiologic finding of the ambient cistern on the CT scan. Complete compression of the ambient cistern was always associated with coma, a partially compressed ambient cistern with stupor or drowsiness, while a normally shaped ambient cistern was associated with a normal level of consciousness. Immediate surgical decompression of the posterior fossa was life-saving for patients with brainstem compression and upward transtentorial herniation. Mortality was 57% for comatose patients and 9% for drowsy or stuporous patients. Ventriculostomy alone is the treatment of choice in cases with only hydrocephalus without brainstem compression or transtentorial herniation.

Glycohistochemical visualisation of mannose-binding lectins in the microvasculatures of brain and brain tumours.

Alpha-mannosylated albumins with three types of linkage between sugar and protein were compared. The results showed their histochemical binding to be sensitive to the nature of the linkage configuration. One configuration permitted visualisation of lectin losses from the tumour blood vessels, already known from biochemical analysis.

Cellular glycoconjugates and their potential endogenous receptors in the cerebral microvasculature of man: a glycohistochemical study.

Protein-carbohydrate interactions are supposed to play a pivotal role in mediation of recognitive interactions, relevant to cellular interactions and transport. The brain microvasculature is the site of numerous cell-cell and cell-matrix recognitive interactions. Assuming carbohydrate-protein interactions play important physiological roles here, then specific carbohydrate-binding proteins should be prominent components of this microvasculature, in addition to the wealth of endogenous glycoconjugates reported by other authors. Human brain and brain tumor microvessels were analyzed histochemically for expression of endogenous sugar-binding proteins using a panel of biotin-conjugated, chemically glycosylated probes with specificities for alpha-/beta-D-galactosides and -D-glucosides, alpha-L-fucosides, alpha-D-mannosides, and beta-D-xylosides, and for expression of endogenous glycoconjugates using a panel of biotin-conjugated plant lectins with specificities for fucoside, galactoside, mannoside and glucoside moieties. Wax-embedded aldehyde- or Bouin-fixed tissues or acetone-fixed frozen sections were examined. Blood-brain barrier function was checked by ascertaining immunohistochemically the extravasation of serum albumin in these tissues. Microvessels in normal human brain tissues (with intact blood-brain barrier) contained abundant endogenous sugar-binding proteins with specificities for beta-galactosides, alpha-mannosides and beta-xylosides, and lesser amounts of proteins binding alpha-galactosides, alpha-fucosides and glucosides. Endogenous glycoconjugates bearing beta-galactoside, alpha-D-mannoside/alpha-D-glucoside or alpha-L-fucoside moieties were also abundant. In brain tumors (with defective blood brain barrier) the microvessels contained altered patterns of endogenous sugar-binding proteins, particularly noticeable in glioblastomas, in which there were notable alterations in galactoside-binding proteins in the microvessels.

Extra-intracranial bypass surgery for vertebrobasilar insufficiency due to obstructive vertebral artery and vertebral-basilar artery junction disease.

This report is on 19 patients with vertebrobasilar insufficiency in whom direct extra-intracranial arterial bypass surgery to the posterior circulation was performed. In all patients preoperative angiography had demonstrated vascular lesions of haemodynamic significance of either one or both vertebral arteries (VA) or within the vertebral-basilar artery junction (VABAJ). The bypass procedure was performed between the occipital artery (OA) and - depending on the localization of the obstructive vascular lesion - the posterior inferior cerebellar artery (PICA), the VA or the anterior inferior cerebellar artery (AICA). A modification of the operative technique is presented with using a paramedian approach. The clinical results of this series support the concept that a patent extra-intracranial graft to the posterior circulation may have a protective effect by preventing further ischaemic events.

Recurrent pituitary adenomas.

Based on 880 pituitary adenomas operated upon between 1972 and 1982 the diagnostic and therapeutical strategy in recurrences is discussed. The incidence of reoperations was 7.75%, 3.7% in hormonally inactive and 4.1% in hormonally active recurrences. The rate was 30% after transcranial surgery--due to the extension of the tumours--and 5% after the trans-sphenoidal approach. In hormone inactive adenomas visual impairment in 29 out of 50 recurrences caused a second operation combined with radiotherapy in 13 cases. Radiotherapy alone was used in 17 cases. In hormonally active adenomas the treatment of persistent hormonal excess represents the main therapeutical problem. With HGH-producing adenomas a return to normal was achieved in 22 cases mainly by a combination of reoperation and radiotherapy (12) or radiotherapy (8) alone. Radiotherapy should be avoided in young patients whenever possible. The procedure of choice in PRL-producing adenomas (14 cases) seems to be treatment with dopamine-agonists (9). An additional reoperation was necessary in five cases.

Radionuclide angiography and Doppler sonography to detect patients with cerebrovascular disease. A correlation with radiographic angiography.

Cerebral radionuclide angiography with 99mTc pertechnetate (RNA) and directional Doppler sonography (DS) were employed to study patients with cerebrovascular disease (CBVD). The 86 patients investigated were divided following radiographic angiography (RGA) into normals (n = 26) and into patients with intracranial (n = 22) and extracranial (n = 38) vascular lesions. Of the patients with angiographically demonstrated CBVD, RNA detected 90%, DS 53.3%. The combined evaluation had a sensitivity of 93.3%. If intracranial arterial disease was excluded, the sensitivity of the studies was 92.1% for RNA and 84.2% for DS and combined evaluation had a sensitivity of 97.4%. The diagnostic accuracy by combined evaluation was 93.8% for the extracranial arterial lesions if the clinical findings were also used in patients with normal RGA pattern. RNA and DS complement each other as RNA contributes to the detection of intracranial blood flow alterations indicating vascular changes in either the extra- or intra-cranial vessels and helps confirm and complete DS findings.

Selection of patients for extra-intracranial arterial bypass surgery based on rCBF measurements.

Extracranial intracranial arterial anastomosis is gaining acceptance as a form of treatment in selected cases with ischemic cerebrovascular disease. To establish indications for this operation and to provide an objective assessment of postoperative results, regional cerebral blood flow (rCBF) studies were performed in 110 patients with cerebrovascular insufficiency considered for extra-intracranial bypass surgery. The 133Xe intracarotid injection method with 16 externally placed detectors was used for measuring rCBF. Postoperatively, rCBF was measured in 40 patients. From these results our present criteria for surgery have evolved. The probability of a good postoperative result is best in patients who showed focal cerebral ischemia or a moderate general reduction of CBF with an additional ischemic focus. The operation is contraindicated in patients with either normal or severely reduced CBF values (less than 60% of normal).

Clinical experience with extra-intracranial arterial anastomosis in 65 cases.

Clinical results of an extra-intracranial arterial bypass (EIAB) procedure for cerebral ischemia are assessed in 65 patients. The 5-year-study suggests that the EIAB procedure has a protective effect against further clinically significant cerebrovascular accidents in properly selected patients. Correlation with angiography and regional cerebral blood flow (rCBF) studies are discussed. It is felt that rCBF measurements offer the best diagnostic test to determine which patients are suitable for surgery by revealing if an ischemic or relative ischemic focus is present. The surgical procedure is contraindicated in acute cerebral ischemia and when the rCBF study reveals general reduction of cerebral blood flow as opposed to a localized ischemic focus.