Endoscopy guided by an intraoperative 3D ultrasound-based neuronavigation system.

OBJECTIVE: We have investigated the feasibility of using 3D ultrasound-based neuronavigation for guiding neuroendoscopy. METHODS: A neuronavigation system with an integrated ultrasound scanner was used for acquiring the 3D ultrasound image data. The endoscope with a tracking frame attached was calibrated to the navigation system. The endoscope was guided based on intraoperative 3D ultrasound data in 9 operations. In 5 of the operations, ultrasound angiography data were also obtained. Updated image data (e. g., more than one 3D ultrasound dataset) were obtained in 6 of the operations. RESULTS: We found that the image quality of 3D ultrasound was sufficient for image guidance of the endoscope. Planning of the entry point and trajectory as well as finding optimal sites for fenestration were successfully performed. Blood vessels were visualized by 3D ultrasound angiography. In one procedure of third ventriculostomy, the basilar artery was visualized. Updated image data were quickly obtained, and in two of the cases, a reduction of the size of cysts was demonstrated. CONCLUSIONS: 3D ultrasound gives accurate images of sufficiently high quality for image guidance of neuroendoscopy. Updated 3D ultrasound datasets can easily be acquired and may adjust for brain shift. Ultrasound angiography image data are also available with this technology and can visualize vessels of importance.

Acute spontaneous subdural haematoma after transsphenoidal surgery.

Only one case of acute spontaneous subdural haematoma (ASSDH) has been reported following transsphenoidal surgery, whereas, another case of chronic SDH has been reported. We present a patient with pituitary apoplexy, who was treated by transsphenoidal surgery. 8 days postoperative he developed an ASSDH requiring immediate surgical evacuation. This case documents the third occurrence of SDH as a complication of transsphenoidal surgery and is the first report of ASSDH that required immediate surgical evacuation.

Interleukin-1beta potentiates endothelin ET(B) receptor-mediated contraction in cultured segments of human temporal artery.

Segments of human temporal artery were placed in organ culture for up to 4 days and examined for endothelin ET(B) receptor activity in the presence and absence of the pro-inflammatory cytokine interleukin-1beta (IL-1beta) by in vitro pharmacology and reverse transcriptase-polymerase chain reaction (RT-PCR). The contractile effect of prostaglandin F2alpha (used as a reference), was not significantly altered by culture or IL-1beta. However, the selective ET(B) agonist sarafotoxin S6c induced no contraction in fresh arteries, but marked contraction after culture. Both maximal contraction and potency to sarafotoxin S6c were increased in segments incubated with IL-1beta . The contraction was sensitive to BQ 788 (ET(B) antagonist), but not FR 139317 (ET(A) antagonist). Actinomycin D abolished the contraction, whereas only the cytokine-induced increase in contraction was inhibited by cycloheximide. ET(A) and ET(B) receptor mRNAs were detected in all arteries; predominantly for the ET(A) receptor in fresh arteries, and for the ET(B) receptor after culture. However, there was no change in the ET(A)/ET(B) receptor mRNA ratio after treatment with IL-1beta. This suggests de novo synthesis of contractile ET(B) receptors after organ culture and that IL- 1beta may further stimulate translation of the mRNA to active receptors. The results raise the possibility that contractile ET(B) receptors may be implicated in disease states with inflammatory processes.

Increased endothelin ETB contractile activity in cultured segments of human temporal artery.

Contractions induced by endothelin-1, endothelin-3 and the selective ETB agonist, sarafotoxin S6c, were studied in segments of human temporal artery. The results in fresh arteries were compared with those obtained after 1 or 4 days in organ culture, and with the specific ETA antagonist FR 139,317, the specific, mixed antagonist bosentan, or the specific ETB antagonist, BQ 788. Sarafotoxin S6c induced no contractile activity in fresh artery segments, but elicited marked contractions after culture. This contraction was only slightly inhibited by FR 139,317, but was abolished by BQ 788. Contractions induced by endothelin-1 were antagonized by FR 139,317 and bosentan, but not by BQ 788. Organ culture did not change the overall pattern, but all concentration-response curves were shifted leftwards. Contractions induced by endothelin-3 were abolished by all antagonists in fresh arteries, but some activity was restored after organ culture. Sensitivity to endothelin-3 was markedly increased. The results suggest a change in endothelin receptors during organ culture, resulting in a marked increase in contractile ETB activity, and possibly some increase in ETA activity. Such changes illustrate the complexity of endothelin responses in this vascular bed.

Relaxation of human temporal artery by endothelin ETB receptors.

Endothelin receptors have been characterized in human temporal artery by molecular biological methods and in vitro pharmacology. Reverse transcriptase-polymerase chain reaction was used to detect mRNA encoding ETA and ETB receptors in normal and endothelium-denuded arteries. Vasomotor response experiments with a specific ETA antagonist (FR 139317) suggested the presence of ETA subtypes. Marked ETB-mediated relaxation was obtained with ET-3 when ETA activity was blocked in precontracted arteries. Relaxation was significantly reduced by bosentan, indomethacin, and a nitric oxide synthase inhibitor. It may be speculated that the relaxant activity is mediated through ETB1 receptors.

Idiopathic normal pressure hydrocephalus: the CSF tap-test may predict the clinical response to shunting.

A follow-up study was performed in nine patients with idiopathic normal pressure hydrocephalus (NPH) 37 months (mean) after shunting and 10 non-operated controls with comparable degrees of ventricular enlargement, gait disorder, and dementia. Five operated patients vs. no controls reported sustained general improvement (p < 0.02). Objectively improved gait at follow-up (compared with preoperative status) was found in five of the six tested NPH-patients vs. none of the controls (p < 0.005). Improved gait and/or psychometric function was found in four of six NPH vs. none of eight control patients (p < 0.02) after drainage of 40 ml cerebrospinal fluid (CSF tap-test). Improved gait during the CSF tap-test predicted continued improvement at follow-up. Temporal horn size was the only radiological variable which showed a (moderate) positive correlation with resistance to CSF absorption and rate of pressure increase. The size of the third ventricle diminished in parallel with clinical improvement.

[Intracranial tumors in children (under 15 years)]. / Intrakraniale svulster hos barn (< 15 år).

Primary intracranial tumours develop in 30-35 Norwegian children each year. Of these tumours, astrocytomas are the most frequent, followed by medulloblastomas, oligoastrocytomas and ependymomas. In this article we give an overview of tumour classification, epidemiology, diagnosis, treatment and prognosis of intracranial tumours in children.

[Intracranial tumors in adults (over 15 years)]. / Intrakraniale svulster hos voksne (> 15 år).

Primary intracranial tumours develop in 420 adult Norwegians each year. Of these tumours, gliomas are the most frequent, followed by meningiomas, pituitary adenomas and acoustic neurinomas. Glioblastomas represent more than 50% of the gliomas. Less than 10% of the patients with glioblastoma survive for two years, despite aggressive therapy (surgery, radiotherapy and chemotherapy). The prognosis for low grade gliomas is much better. In the case of meningiomas, 95% of the tumours are benign. The primary treatment for meningiomas is surgery. If surgery is impossible, radiosurgery should be considered. Pituitary adenomas are often hormone-secreting (e.g. prolactin, growth hormone, adrenocorticotrophic hormone). Many prolactinomas are treated with bromocriptine alone. The rest of the pituitary adenomas are treated by microsurgery and radiotherapy. The prognosis for patients with pituitary adenomas is good. Acoustic neurinomas, which in most cases are benign, are treated by microsurgery or radiosurgery. Postoperative morbidity due to cochlear nerve and facial nerve dysfunction is a problem. Brain metastases are far more frequent than primary intracranial tumours. Solitary metastases in patients with stable systemic disease should be treated by surgery or radiosurgery.

Low concentrations of lithium and cyclooxygenase inhibitors enhance endothelin-1 (ET-1)-induced contractions in human temporal artery, but not in porcine ophthalmic artery.

Endothelins are a recently discovered group of potent vasoconstrictor peptides synthesized by endothelial cells and other tissues in various species, which seem to participate in the regulation of vascular tonus. Abnormalities in vasoactivity in the head may be an important event in headache pathophysiology, although the mechanisms responsible for such constrictions and/or dilations are not known. The endothelium and its constrictor peptide, endothelin, may play a key role in such mechanisms. Of the various drugs used in the treatment of headache, lithium is an accepted treatment for cluster headache, and indomethacin is the drug of choice for the associated condition chronic paroxysmal hemicrania. The mechanism of action of these drugs in these headaches is not known. Due to the possible involvement of endothelin in headache disorders, the objective of this study was to verify the effects of lithium and cyclooxygenase inhibitors (indomethacin, acetylsalicylic acid and naproxen) on endothelin-1 (ET-1)-induced contractions in isolated human temporal arteries and porcine ophthalmic arteries. It was found that all drugs increased the (ET-1)-induced contractions in human temporal arteries. Conversely, there were no significant changes induced by the drugs in porcine ophthalmic arteries. These results are consistent with the variation of activity often seen in different vascular beds and between species. The potential importance of such reactions for the understanding of vascular changes putatively involved in headache development and treatment is discussed.

Pleomorphic xanthoastrocytoma as a component of a cerebellar ganglioglioma: case report.

A 27-year old male patient underwent surgery for a cerebellar ganglioglioma in which a pleomorphic xanthoastrocytoma constituted the gliomatous element. Neither radiation nor chemotherapy was administered. The patient was well for 12 years and then he suffered a recurrence and underwent a gross total resection. Histological examination revealed a ganglioglioma with thrombosed blood vessels, areas of tumor necrosis, and scattered mitoses. These anaplastic changes, which were restricted to the glial component of the tumor, may herald a more aggressive clinical course. However, 11 months after the second operation, there have been no signs of tumor recurrence.

The Chiari type I malformation in two monozygotic twins and first-degree relatives.

The presence of the Chiari type I malformation in 2 adult monozygotic female twins, their mother, and possibly in 2 of their 4 daughters is reported. The diagnosis was made by magnetic resonance imaging and confirmed at the time of surgery in 1 twin. Monozygosity of the twins was proved by DNA typing. The disorder in the present family should probably be classified together with the autosomal dominant craniocervical malformations. Nongenetic factors also seem to be important because the twins were discordant for the extent of herniation of the cerebellar tonsils and the presence of syringomyelia.

[Microsurgery in lumbar nucleus prolapse]. / Mikrokirurgi ved lumbale nukleusprolaps.

The article describes the cases of 83 patients with lumbar herniated discs operated by means of microsurgical technique since August 1987. In 69 patients the result was good and they had no symptoms. Ten patients had improved, but were not free of symptoms. Four patients had not improved. The time spent in hospital postoperatively varied from one to ten days, with a mean of five days. The mean period off work after operation was two months and three days. The method is an alternative to standard discectomy in patients with lateral herniated discs.

Late post-concussional symptoms in traumatic head injury. An analysis of frequency and risk factors.

During follow-up of 485 adult patients with traumatic head injury, 51% of the patients reported new post-concussional symptoms after an observation period of 3-5 years (mean 4.0 years). Most data, including the level of consciousness on admission, length of post-traumatic amnesia and days of hospitalization were poor parameters for predicting which patients would suffer late complications. A few variables were statistically of predictive importance: Sex, repeated head injury and skull fracture. Age was a risk factor for multiple complaints.

Return to work and social adjustment after traumatic head injury.

During follow-up of 485 adult patients with mainly mild head injury 27% of the patients were unemployed after an observation period of 3-5 years (mean 4.0 years). The length of sick leave during the last 3 years was longer than for a control group. Reduced physical capacity and time of sick leave during the last 3 years were the variables which were most closely associated with unemployment at follow-up. The long term family life, contact with friends and income were less favourable in the head injured patients than in the control group.

Arachnoid cysts of the middle cranial fossa and traumatic complications.

A 17-year-old boy is reported with chronic subdural hematoma and a unilateral grade III arachnoid cyst in the middle cranial fossa. After operation he recovered completely. Attention is drawn to the liability of these arachnoidal cysts to hemorrhagic complications. Subdural hematoma, subarachnoidal hemorrhage and intracystic bleeding have all been reported. These may follow otherwise insignificant trauma to the head, and may have major legal implications in cases of assaults.

Head injury in road traffic accidents. A prospective Study in Trøndelag, Norway, 1979-80.

The purpose of the present prospective investigation was to study the epidemiology of head injuries sustained in road traffic accidents. The characteristics of all 503 head-injured patients admitted to hospitals in the two counties of Trøndelag province, Norway, in 1979 and 1980 are described. The annual incidence was 89 per 100 000 inhabitants. There was a male preponderance in all categories of victims. The highest male to female ratio was found in motorcyclists and mopedists (6.3:1). Pedal cycle accidents accounted for 33% of all accidents, constituting the most common cause of head injury on the roads in the period from May to the end of September. There were more pedal cycle accidents in the present series than in previous studies on road traffic accidents.

Hospital admitted head injury. A prospective study in Trøndelag, Norway, 1979-80.

Head injury ranks among the leading causes of disability and death in the prime of life. The purpose of the present prospective investigation was to study head injuries necessitating hospital admission in our region. The characteristics of 1124 such head injuries in Trøndelag in 1979-80 are presented. The annual incidence was 200 per 100 000 inhabitants. Young males were most often affected. The incidence was higher in males than in females in all age ranges. Road traffic accidents were the most common cause of head injury, but home accidents had higher rates of skull fractures and intracranial haematomas. Both lethality and duration of hospitalization increased with age.