Bengt Liliequist

An adapter for computed tomography-guided stereotaxis

A new, versatile adapter for computed tomography-guided stereotaxis is presented. The instrument consists of a light aluminum frame, which by means of a nasion support and two ear plugs is fixed to the patients head. Reproducibility of repeated fixations is very high. The adapter is fitted to most stereotactic frames and can be used in all adult patients. Comparison between computed tomography- and ventriculography-guided determinations of thalamic targets showed a mean difference of 0.6 and 0.7 mm for the x and y coordinates, respectively. The z coordinates seldom showed any measurable difference. We now perform all types of stereotactic neurosurgery (tumor biopsy, implantation of depth electrodes, thalamotomy, dentatotomy, cingulotomy, etc.) with computed tomography guidance only. The short-term results in a small number of patients have been at least as good as after conventional ventriculography-guided surgery. In addition to open stereotactic surgery, the adapter is also suitable for external stereotactic irradiation of intracranial targets with a linear accelerator.

Effect of cranioplasty on cerebrospinal fluid hydrodynamics in patients with the syndrome of the trephined

SummaryForty patients with cranial bone defects after craniectomy underwent extensive cerebrospinal fluid (CSF) hydrodynamic investigations by means of a CSF infusion test before and after cranioplasty. The results of these investigations were related to the clinical signs of the patients before and after cranioplasty and to the size and location of the skull bone defect. Twenty-two patients were considered to have “the syndrome of the trephined” (ST). The remaining patients were either free of symptoms or had symptoms not related to ST.CSF hydrodynamic variables that were changed before and normalized after cranioplasty include the following: Resting pressure, sagittal sinus pressure, buffer volume, elastance at resting pressure and pulse variations at resting pressure. The changes were statistically significant mainly in ST patients who were also relieved of their symptoms after cranioplasty.

Antifibrinolysis with tranexamic acid in aneurysmal subarachnoid hemorrhage: a consecutive controlled clinical trial.

A randomized controlled clinical trial was carried out to study the effect of tranexamic acid (AMCA, Cyklokapron; AB Kabi, Stockholm, Sweden) in the prevention of early rebleeding after the rupture of an intracranial aneurysm. The incidence of vasospasm, hydrocephalus, cerebral ischemic and thromboembolic complications, morbidity, and mortality was also evaluated. The series comprises 59 patients, 30 treated with tranexamic acid and 29 controls. The treatment was stopped if there was rebleeding, operation, or discharge from the hospital. There were 6 recurrent hemorrhages in 6 patients in the tranexamic acid-treated group and 11 recurrences in 7 patients in the control group. Recurrent hemorrhages occurred later in tranexamic acid-treated patients than in controls. Five patients in each group died from rebleeding. Five additional treated patients and 2 controls died from cerebral ischemic dysfunction. The results suggest that tranexamic acid may protect patients with ruptured aneurysms from rebleeding for 1 or 2 weeks, but that it also may produce cerebral ischemic complications.

Spontaneous thrombosis of ruptured intracranial aneurysms during treatment with tranexamic acid (AMCA). Report of three cases.

SummaryRadiographically verified spontaneous disappearance of medium-sized arterial cerebral aneurysms is seldom reported, and only three times in connection with antifibrinolytic therapy (EACA). In our clinic repeat angiograms have shown non-filling of the aneurysms in three patients during treatment with tranexamic acid (AMCA) two, three, and four weeks respectively after primary bleeds. Initially, all three patients had severe radiological vasospasm associated with neurological deterioration. Follow-up angiograms have demonstrated partial reappearance of the aneurysm after one month in one patient and complete disappearance of the aneurysms in the other two patients after 9 and 22 months respectively. In two cases occlusion of cerebral arteries occurred. With regard to the higher risk of severe vasospasm and occlusion of cerebral arteries in our opinion it should not be a therapeutic goal to try to achieve a thrombosis of a ruptured aneurysm with antifibrinolytic drugs.The reason for spontaneous aneurysm thrombosis during treatment with AMCA may be a local inhibition of plasminogen activators in and around the aneurysm wall. It may also be related to the sympathomimetic property of the drug, with vasospasm and a subsequent flow-reduction inside the aneurysm or a possible interaction with other drugs and substances.

Primary malignant melanoma of the central nervous system

SummaryAmong 10 patients with primary malignant melanoma of the CNS, the tumour was localized to the brain in 7 cases (group I) and to the spinal cord in the remaining 3 cases (group II). A mean age of about 50 years and a male preponderance were found. In group I there were various neurological symptoms, and cerebral arteriography disclosed either vascular or non-vascular lesions. Diagnosis was made at light microscopic examination of material obtained at operation or autopsy. The tumour was either diffuse or localized and involved both the leptomeninges and cerebral parenchyma. After operation the patients survived for between 2 weeks and 7 months. In group II there were compression symptoms and pathological gas myelography. At operation tumours were found that involved the leptomeninges and medulla. Light microscopic examination showed malignant melanoma. The postoperative survival was longer (12 months-2 years and 9 months) than in group I.

Treatment of spontaneous intracerebral haemorrhage. A retrospective analysis of 74 consecutive cases with special reference to computertomographic data

SummaryThe surgical treatment of spontaneous intracerebral haemorrhage (SIH) is still a matter of controversy, although most Neurosurgeons agree that surgery is indicated in selected cases. The introduction of computer tomography (CT) permits a more accurate determination of the localization, size and expansion of an intracerebral haemorrhage. The aim of this study is to evaluate the results of surgical and conservative therapy in selected cases and to search for parameters that could help to predict the outcome and facilitate the decision between surgery and conservative therapy.Seventy-four patients treated following SIH during the years 1976–1980 were analyzed. The decision for surgical treatment was made on the basis of the patients conditions and the findings in the CT scan. Thirty-nine patients with mainly medium-sized haemorrhages underwent surgery and 35 were conservatively treated. The mortality after three months was 5/39 (13%) in the surgical and 7/35 (20%) in the conservative group. The volume of haemorrhage was significantly larger in the patients who died and 9/10 patients with a haematoma volume above 80 ml died. Five of these 10 were operated and the other 5 not and surgery seemed to be of little benefit to this group. Dilatation of the contralateral ventricle is another indicator of a bad prognosis.Long-term follow-up investigation was carried out 4–38 months after the initial treatment. Total mortality was 19 out of 68 patients that could be reached for late follow-up. Eleven patients (29%) were fully recovered and 16 had minor neurological deficits. There was no difference in late results between the surgical and the conservative groups, but the patients in the surgical group were generally in a worse condition and had larger haemorrhages that the others. The fact that the total mortality in this material is lower than in other conservatively treated series favours surgery in selected cases of SIH. The use of CT gives valuable information as to the prognosis and especially the volume of haemorrhage seems to be a good prognostic factor.

Traumatic lateral sinus thrombosis. Report of two cases.

Two cases with thrombosis of the transverse sinus caused by a fracture crossing the sinus are reported, and the roentgenological changes seen in cerebral angiography are discussed. In 1 case, a filling defect was seen which at subsequent autopsy was found to correspond with an intraluminal thrombosis. In the other case, not verified at autopsy, the angiographic changes were consistent with a thrombosis of a transverse sinus.

Hodgkin's disease primarily localized to the brain

SummaryA case of primary Hodgkins paragranuloma of the brain is described. The benignancy of the lesion is shown both by the microscopical appearance and by the clinical course of the disease. It seems that this is the first case of intracranial Hodgkins paragranuloma to be described, and that all forms of the disease can affect the brain. The possible origin of the tumour is discussed.

Quantitative estimation of tumor volume on computer assisted tomography.

With the use of computer assisted tomography (CAT), the volume of intracranial hemorrhages can be calculated. The present work outlines a method that, based on EMI scan printouts, makes possible a calculation of the volume of hemorrhages, tumors, or other pathological changes detectable on CAT with a high degree of accuracy, even when the pathological changes are irregular in shape. Thus, there have been divergences between the estimations of volume of meningiomas using this method and the measure of the volume of the enucleated meningiomas within the range of 0 to +5%. An example of such a meningioma, and the calculation of its volume, is presented.

Absent cervical pedicle

SummaryCongenital defect of a cervical pedicle produces a rare clinical syndrome with a characteristic X-ray picture associated with vague clinical signs often accentuated after trauma. A careful analysis of the X-ray films, including oblique views, shows the congenital defect of the pedicle and the associated abnormalities which can all be attributed to a defect in the neural arch centre of chondrification. Further X-ray examinations including myelography with or without vertebral angiography as well as surgical exploration should be unnecessary.A case of absence of the right pedicle of the sixth cervical vertebra is described. The symptoms in this patient were not caused by the malformation, but by an associated enlarged seventh cervical transverse process which produced a thoracic outlet syndrome.