Search

Rationale: Arterial vasospasm has rarely been reported following temporal lobectomy for intractable epilepsy., Case Presentation: A 31-year-old patient presented with a global aphasia 2 days after a left dominant anteromesial temporal lobectomy for intractable epilepsy. Magnetic resonance imaging on 5th post-operative day revealed severe narrowing of M1 segment of the left middle cerebral artery (MCA) and Transcranial Doppler (TCD) ultrasonography an increased velocity of the MCA that suggested a severe vasospasm. The patient received continuous intravenous hyperhydratation and nimodipine; aphasia improved within 24 h and resolved completely within 6 weeks, associated with velocity reduction on control TCD., Conclusion: Transient vasospasm is a likely underestimated cause of focal deficit following temporomesial resection that deserves appropriate treatment.

After endovascular coiling, several authors have reported refilling of the aneurysm, appearance of a mass effect, coils protruding into the parent artery, migration of coils into parent artery or through aneurysm wall, and compression of the parent artery by coil impaction. This is the first report of an endovascular coil transfixing a cranial nerve. We present a 59 year old man who presented with a symptomatic bilobulated aneurysm of the right internal carotid artery. The aneurysm was embolised by endovascular coiling. Angiographic follow up showed occlusion of the aneurysm. Five years later, the patient complained of progressive diplopia with ptosis. Follow-up angiography showed renewed filling of the aneurysm at its neck. The aneurysm was clipped surgically. At operation, a coil mass effect was noted and one coil penetrated the fibres of the right oculomotor nerve.

Symptomatic pituitary metastasis and intraventricular haemorrhage from a cerebral metastasis are exceptional events in the natural history of a renal cell carcinoma. We report the first case of a metastatic renal cell carcinoma to the pituitary gland presenting with intraventricular haemorrhage. The origin of intraventricular haemorrhage and its association with renal cell carcinoma pituitary metastasis are discussed.

One of the most recent laser treatment modalities in neurosurgery is interstitial laser thermotherapy (ILTT). In this review, experimental and clinical studies concerning intracranial ILTT are discussed. Two methods for intra-operative control of the laser induced lesions are described; i.e., computer-controlled power delivery, using a thermocouple that is positioned interstitially at the periphery of the tumour to maintain the desired temperature at that point, and MRI, to visualise the extent of the thermal lesions induced by ILTT. The results show that ILTT using a Nd: YAG laser is easy and relatively effective in the treatment of small deep-seated brain tumours with minimal risk and complications. This review is concluded with suggestions for further improvement of this treatment modality.

From initial experiments of ruby, argon and CO2 lasers on the nervous system so far, dramatic progress was made in delivery systems technology as well as in knowledge of laser-tissue interaction effects and hazards through various animal experiments and clinical experience. Most surgical effects of laser light on neural tissue and the central nervous system (CNS) are thermal lesions. Haemostasis, cutting and vaporization depend on laser emission parameters--wavelength, fluence and mode--and on the exposed tissues optical and thermal properties--water and haemoglobin content, thermal conductivity and specific heat. CO2 and Nd-YAG lasers have today a large place in the neurosurgical armamentarium, while new laser sources such as high power diode lasers will have one in the near future. Current applications of these lasers derive from their respective characteristics, and include CNS tumour and vascular malformation surgery, and stereotactic neurosurgery. Intracranial, spinal cord and intra-orbital meningiomas are the best lesions for laser use for haemostasis, dissection and tissue vaporization. Resection of acoustic neuromas, pituitary tumours, spinal cord neuromas, intracerebral gliomas and metastases may also benefit from lasers as accurate, haemostatic, non-contact instruments which reduce surgical trauma to the brain and eloquent structures such as brain stem and cranial nerves. Coagulative lasers (1.06 microns and 1.32 microns Nd-YAG, argon, or diode laser) will find an application for arteriovenous malformations and cavernomas. Any fiberoptic-guided laser will find a use during stereotactic neurosurgical procedures, including image-guided resection of tumours and vascular malformations and endoscopic tumour resection and cysts or entry into a ventricle. Besides these routine applications of lasers, laser interstitial thermotherapy (LITT) and photodynamic therapy (PDT) of brain tumours are still in the experimental stage. The choice of a laser in a neurosurgical operating room implies an evaluation of the laser use (applications, frequency), of the available budget and costs--including purchase, maintenance and staff training--, and material that will be necessary: unit, peripherals, safety devices and measures, training programme. Future applications of lasers in neurosurgery will come from technological advances and refined experimental applications. The availability of new wavelength, tunable, small sized and "smart" laser units, will enlarge the thermal and non-thermal interactions between laser energy and neural tissue leading to new surgical applications. Tissue photo-ablation, photohynamic therapy using second generation of photosensitizers, updated thermotherapy protocols, are current trends for further use of lasers in neurosurgery.

The authors, since 1985, have used 587 Madreporic Coral grafts as bone substitute in a total of 183 patients, among them in 80 cases for repair of cranial base bone defects. They report their long-term results. Partial resorption to about 40% of the initial volume occurred in almost all cases within 8 to 10 months, with complete resorption after about one year. 20% of the coral blocks moved spontaneously or split into pieces, but could easily be withdrawn rhinoscopically through the nostrils. No CSF leakage was noticed afterwards. The local infection rate was only 4%, always close to the basal coral graft. This is lower than the infection rate after using autologous bone harvested from the inner table of the bone flap (20%). Infections were cured by removal of the coral graft. Despite the mentioned draw backs, Madreporic Coral graft implants can be recommended as bone substitute in cranial base surgery: 1. The material simplifies the surgical procedure; 2. Harvesting of autologous bone is no longer necessary; 3. Transmission of infections like AIDS, Hepatitis C or Creutzfeld-Jacob-disease can be avoided with certainty.

The authors present their clinical experience with 1.32 microns Nd-YAG Laser. After a series of experimental studies which demonstrated the adaptability of such a wavelength to central nervous surgery, they used such a Laser during current neurosurgical procedures. The MC 2100 unit combines two wavelengths 1.32 microns and 1.06 microns, and two emission modes: continuous wave (c.w.) and pulsed. This Laser has been used during 70 procedures: 54 supra-tentorial, 8 infra-tentorial, 5 intra-spinal, 3 intra-orbital, 600 microns and 400 microns fibers were preferred in most cases, either with a telescopic light handpiece or- less often--with a focussing handpiece. The quality of vaporization--close to that of CO2 Laser- and of haemostasis-close to that of 1.06 microns Nd-YAG Laser-makes this 1.32 microns wavelength very suitable for neurosurgery. The manoeuverability due to the optic fibers is most interesting. Furthermore, such a Laser should have in the near future large applications in stereotactic and/or endoscopic neurosurgery.

New therapeutic modalities for Ethmoidal Adenocarcinomas are presented. Thirty three patients harbouring such a tumour have been treated during the last four years. Twenty three were included in the following protocol:--the first step consisted in inductive chemotherapy based on a four-day course of continuous cisplatine (CDDP) and 5-fluoro-uracyl (5-FU infusion)--the second step was the tumour removal, which was performed through a combined transfacial and subfrontal approach. A contralateral ethmoidectomy was always performed. The integrity of the sphenoidal sinus was systematically checked. The cranial base was reconstructed with madreporic coral grafts; then a large extra-dural pediculated galea flap was placed onto the anterior base to line the sub-frontal dura. The authors discuss the results of this series of rare tumours.

The authors have been using CO2-laser radiation routinely for more than 2 years. After having recalled the basic thermal properties of this beam, they present their experience. The goal of this work is to point out the particular benefit of CO2-laser cautery to perform tumoral haemostasis. The technical data of this CO2-laser haemostasis are detailed for 3 main indications: In cases of a precise origin of the haemorrhage, the coagulation of small intratumoural vessel necessitates a low output power: 2-4 watts in continued emission; 10-15 watts in the pulsed mode. The beam must be defocussed so as to be as large as the aimed vessel. A micro-manipulatotor is necessary for deeply located tumours. Basal meningiomas, neurinomas, giant adenomas are the best indications. If a diffuse bleeding is encountered in the operative cavity the output must be a little higher: 3-8 watts in continuous mode or 15-30 watts in the pulsed mode; first the cavity is swept with a defocussed CO2-laser ray; then the few larger vessels which have not been cauterized are coagulated one by one either by laser or by bipolar coagulation. The insertion zone of a meningioma can be efficiently coagulated by CO2-laser: a 150-200 watts output in the pulsed mode is necessary if the attachment is dural, a 300-400 watts pulsed output in the case of bony infiltration.