Diagnostic limitations in the treatment of cerebral aneurysms.

BACKGROUND: Endovascular coiling has become a standard technique in the treatment of cerebral aneurysms. The mechanisms of recurrence are incompletely understood. METHODS: In our clinical investigations we present three uncommon cases where the pathology at the base might has been underestimated in digital subtraction or magnetic resonance angiography. RESULTS: In the first clinical study rehemorrhage occurred 11 years after endovascular coiling. Before rehemorrhage occurred, serial magnetic resonance angiographies had revealed a stable situation with only a small base remnant after initial endovascular treatment. In the second clinical study, intraprocedural rupture during endovascular coiling occurred and a residual angiographic occult lesion was detected only during microsurgical clipping. In the third clinical study, we again found a residual lesion during microsurgical clipping. CONCLUSION: We present three clinical studies were the pathology at the base might has been underestimated in digital subtraction angiography or magnetic resonance angiography. The incidence of angiographic occult residuals is unknown, but their clinical relevance may be important. Beside other mechanisms, these lesions might be the source of aneurysmal regrowth and hemorrhage (Fig. 4, Ref. 27).

Surgical management of an ACM aneurysm eight years after coiling.

The authors present a case report on rebleeding of a medial cerebral aneurysm (MCA) eight years after complete endovascular coiling. The primarily successfully coiled MCA aneurysm showed a local regrowth which, however, was not the source of the rebleeding. The angiogram demonstrated no evidence of contrast filling of the coiled segment, but according to intraoperative findings (haematoma location, displacement of coils, evident place of rupture) there is no doubt that the coiled segment of the aneurysm was responsible for the haemorrhage.

Microneurosurgical water probe.

When constructing the micro-neurosurgical water ball probe, the authors have simply combined the properties of a ball probe with an irrigational function and the supportive role of water current to form a new irrigating ball dissector. The micro-instrument has an outlet mechanism with which the surgeon can regulate the flow of physiological solution into the operational field. Its point has the properties of a ball probe, and the overall bayonet shape facilitates surgical interventions in deep tissues under microscopic control. The water probe therefore enables the surgeon to perform precise mechanical preparation supported by a regulated current of water and a targeted irrigation in the operational field. The physiological solution in the pressure infusion cuff is under minimal pressure and directly connected to the probe. Due to the fact that one device can be used for various purposes the water ball probe represents an advantageous alternative to conventional micro-neurosurgical preparation.

Surgical or endovascular treatment of carotid stenosis.

Carotid endarterectomy (CEA) is a proved standard treatment in stenosis of high-grade carotid artery stenosis. On the basis of new experience, percutaneous transluminal angioplasty with stent (PTAS) has gradually been established as an alternative method to carotid endarterectomy. The aim of the three-month investigation was to evaluate PTAS, CEA and conservative medicamentous therapy. A group of 75 patients (78 stenoses) with symptomatic and asymptomatic stenoses of the carotid artery of 70 and more percent were evaluated within a unicentric retrospective study. The period of investigation commenced in August 1999, and lasted 14 months. The patients were treated by PTAS (23 patients), CEA (23 patients). Two patients were treated by bilateral stenting. One patient was subdued to both operation and endovascular treatment, while the former treatment was performed on one side and the latter on the contralateral side. This patient was included into both surgical and endovascular groups. The rest of the patients were treated solely by medicamentous therapy (30 patients). During the period of 30 days after the intervention, one patient in both PTAS and CEA groups (4.3%) developed a severe ipsilateral infarction. Recurrent stenoses were recorded in two patients from the PTAS group (8.7%) (sonographically more than 50%), and in one patient from the CEA group (4.3%). Immediately after stent implantation, 12 patients (52.2%) developed pinlike ischemic lesions observed by means of diffusion-weighted MR imaging (DWI). Hyperintensive signals did not lead to any neurologic deficits. After 3 months, none of the latter lesions were found in any of the patients. In the group treated by conservative therapy, only one of the patients (3%) developed a mild infarction. After the evaluation of our experience with peri-interventional PTAS and CEA complications in our small group of investigated patients, it is possible to state that the performance of both methods can be comparably successful. However, at the moment we cannot consider PTAS as an equivalent method. (Tab. 6, Fig. 2, Ref. 33.).

Microsurgical management of a complicated aneurysmal endovascular embolisation with GDC coil: a case report.

We present a case involving a microsurgical approach to solving the problem of a medial cerebral artery (MCA) occlusion occurring after GDC coiling of an internal cerebral artery (ICA) bifurcation aneurysm in a 40 year old woman. We describe the clinical course of the case and discuss technical possibilities and risks of clipping a coiled aneurysm. One key to success is awareness of changes in the aneurysm's properties after coiling. With loss of elasticity the aneurysm had the effect of a tumor fixed on the vessel. The apposition of the aneurysm to the wall of the vessel, as well as the aneurysm's rigidity and increase of intracranial pressure after subarachnoideal hemorrhage (SAH), may lead to occlusion of the vessel. In cases of an mandatory operation due to the occlusion of a main arterial stem after coiling, it is primarily crucial to perforate the aneurysm's fundus, remove the coils, and, finally, to clip the slack neck of the aneurysm. An attempt to precisely prepare and clip the aneurysmal neck without removing the coils could result in the rupture of the aneurysm's neck.

Three cases of hindbrain herniation in adults with comments on some diagnostic difficulties.

In discussing the clinical features and surgical treatment of adult patients with Arnold Chiari deformity type I the authors focus on the differential diagnosis from demyelinating disease and present three illustrative cases. Out of 118 patients initially diagnosed as having demyelinating disease and admitted to our hospital between December 1991 and April 1993, three were subsequently found to have the Arnold Chiari deformity on MRI. The delay until correct diagnosis amounted to 10, 16 and 32 years, respectively. Our study stresses the diagnostic importance of MRI of the craniocervical area in cases of unexplained neurological symptoms and external signs of dysplasia. Accurate examination, early diagnosis and selection of proper surgical management can alleviate severe symptoms in many instances and prevent neurological complications.

Subdural hemorrhage of the cauda equina. A rare complication of cerebrospinal fluid shunt. Case report.

We describe the case of a 16-year-old boy with idiopathic hydrocephalus, who developed cranial subdural hygromas and subsequent cranial subdural hemorrhage after a shunting procedure. Sciatica and radicular lumbar pain initially seemed to be unrelated to the proceeding implantation of a ventriculoatrial shunt. CT scan revealed a sharply demarcated hyperdensity in the lumbar subdural space with compression of the cauda equina. Differential diagnosis considerations included vascular malformations, vascular tumors, benign tumors of meninges or nerve sheets, ependymoma, lymphoma, and metastases. MR investigation did, in fact, clearly recognize this hyperintense space-occupying lesion as blood in the subdural space which outlined the cauda equina. We believe that the spinal subdural hematoma in our case represented an extension of intracranial subdural haemorrhage fluid into the spinal subdural space.

[Stereotaxically guided versus ultrasound guided surgery--a comparative report of experiences]. / Stereotaxiegeführtes versus ultraschallgeführtes Operieren--Ein vergleichender Erfahrungsbericht.

Localisation and approach are the keys of surgery on brain tumours. Apart from the up and coming neuronavigational devices, stereotactical and ultrasound guidance are well established methods in locating intracranial tumours and in selecting the optimal approach for resection. Nevertheless it is not clear, which guidance tool is more practicable in the daily routine. Both methods have been used in our department since 1989. During the last six and half years we have operated on 1314 patients suffering from intracranial tumours. In 148 cases we have used either stereotactical (n = 37) or ultrasonic (n = 111) intraoperative guidance. The performing surgeon had documented ease of use, accuracy and users acceptance of the chosen guidance tool. The data were summarised together with the patients history and images in to a descriptive report. Since 1992 we noted a steady increase in guiding operations from 4% to 24%, mainly due to the more frequent use of ultrasound guidance. Saving time, easy handling, accuracy and plausible guidance with real time pictures have been the major advantages in favouring ultrasound guidance. Additionally, the freedom in choosing the appropriate approach seems to be essential. To achieve full advantage of all these benefits, experience and individual expertise are necessary. Conversely, the high accuracy of stereotactic guidance is not within the reach of the ultrasound, which is sufficient to guide the operation. According to our experiences, we recommend intraoperative ultrasound as an easy guiding tool. Except a few cases, this guiding tool seems to be superior to the stereotactic localisation of intracranial lesions.

[Stereotaxic biopsy of brain tumors]. / Streotaktická biopsia mozgových nádorov.

The work re-evaluates the meaning of stereotactic bioptic examination in 50 neurosurgical patients. Bioptic material gained for histologic purposes does not secure always the achievement of the correct histologic diagnosis. The authors critically reevaluate the possibilities of this diagnostic method. They do not consider as adequate to claim multiple expansive processes to be inoperable, respectively as being refractory towards therapy, when the histologic conclusion is lacking. In cases of inconsistency in histologic conclusions from two neuropathologists the further fate of the patient is conditioned by the neuropathologist's stand-point, but also by the clinical experience of the neurosurgeon who overtakes the final responsibility for the patient's further fate. Recently available methods (CT,MR, spectrography) are diagnostically not so precise as to be able to manage without stereotactic biopsy. (Tab. 3, Fig. 5, Ref. 10.).

[The role of the neurosurgeon in histopathologic diagnosis]. / Moznosti a úloha neurochirurga v histopatologickej diagnostike.

Neurosurgical practice has proved that the establishment of a correct neurohistopathologic diagnosis is sometimes difficult. Inconsistency of diagnoses resulting from unbiased examinations of several neuropathologists is not uncommon. The authors-neurosurgeons-have performed 300 fast neurohistopathologic examinations by means of smear technique. Correct diagnosis was stated in more than 90% of cases. Bioptic examination may represent a contribution in cases where postoperative irradiation is indicated, namely under diagnostically controversial circumstances. The authors re-evaluate the possibilities of utilization of smear technique for the purpose of histopathologic diagnostics performed directly by neurosurgeons. (Tab. 7, Ref. 5.).

[Long-term results in patients with stereotaxic surgery for psychopathologic disorders]. / Dlhodobé výsledky 304 stereotakticky operovaných pacientov s psychopatologickými poruchami.

Long-term results (5-20 years) recorded in 304 patients operated on stereotactically for psychopathologic disorders are presented. The largest group of 260 surgically treated subjects represented aggressive patients. This group consisted of 150 patients with mental retardation, 70 with epilepsy, 20 with schizophrenia, and 20 patients with sexual deviations. Amygdalectomy for patients with normal intellect and posterior hypothalamotomy for those with reduced intellect proved to be the most effective procedure. Symmetrical operations were also effective. In some cases a combination of two target was necessary. In epileptics with aggressivity the combination of amygdalectomy and hippocampectomy yielded the best results. In aggressivity with sexual deviations anterior hypothalamotomy was the most effective operation. Favorable results in aggressivity therapy were recorded in 60% of patients. In patients with criminal sexual deviations, in drug addicts, and in alcoholics, anterior hypothalamotomy was found to be most effective, with favorable results in 50% of patients. In patients with depression, thalamotomy or stimulation of the limbic regions of the thalamus decreased the depression, with favorable results recorded in 66% of patients. The results of the surgically treated patients show that target-oriented stereotactic operations remove psychopathologic symptoms, improve the effectiveness of psychoactive drugs and the social adaptability of patients. (Ref. 15.)

[Extra-intracranial microanastomosis and its future]. / Extra-intrakraniálna mikroanastomóza a jej budúcnost'.

Current examination methods fail to provide exact information on potential conditions for functional rehabilitation of ischemic foci. They do not yield the necessary data which would allow to determine reliably the effect of extra-intracranial microanastomosis on the clinical picture. The potentially positive effect depends on the condition of the ischemic lesion and on the pattern of the individual geometry of the cerebral vascular network. In the light of two case reports the author contests the decisive refusal of extra-intracranial microanastomosis as the therapeutic procedure in cerebral ischemia. Although the effect of microanastomosis does not warrant improvement of the clinical picture, it creates better conditions for its potential development. It is frequently impossible to decide unequivocally whether improvement was due to the operation or whether it had occurred also without it. This, however, is not a unique phenomenon in surgery. The potentiality of its positive effect, inherent to the procedure, is both its shortcoming and guarantee of its further survival.