The extended anterior subcranial approach differs significantly from more traditional surgical approaches to the skull base in that it allows a broad inferior access to the anterior skull base planes with tumor exposure from below rather than via the transfrontal route. The authors initially used the subcranial approach in 1978 for the treatment of high-velocity skull base trauma and certain craniofacial anomalies. In 1980 they expanded the indications to include the combined neurosurgical-otolaryngological resection of various skull base tumors. Osteotomy of the frontonasoorbital external skeletal frame provides optimum anterior access to the orbital and sphenoethmoidal planes as well as to the nasal and paranasal cavities while avoiding frontal lobe retraction and the external facial incisions characteristic of transcranial and transfacial approaches. The improved visualization of the anterior skull base and clival-sphenoidal region facilitates en bloc tumor removal, optic nerve decompression, exposure of the medial aspect of the cavernous sinus, and watertight realignment of the anterior cranial base dura. In this report the authors present their experience over the past 13 years with 104 patients who underwent operation via the extended subcranial approach. Because extensive frontal lobe manipulation and external facial incisions are avoided with this approach, intensive care unit and overall hospital stay are reduced, related complications are minimized, and postoperative cosmetic appearance is enhanced. The extended anterior subcranial method is therefore an excellent alternative to traditional transfacial-transcranial skull base approaches for the removal of selected skull base tumors.

Parallel treatment results in using two options--keyhole craniotomy and standard larger craniotomy--were analysed in the past eight years. Two experienced neurosurgical teams in performing both surgical approaches have reached almost similar morbidity and mortality rates, and overall surgical results. The type of craniotomy is selected according to the experience of the surgical team, and familiarity with certain approach. The authors have good experience with the minimally invasive approach for different intracranial pathology and recommend it especially in neurovascular surgery.

The authors review their experience in the surgery of intracranial aneurysms via an eyebrow keyhole approach. The eyebrow keyhole approach presumes a skin incision in the lateral two-thirds of the eyebrow followed by small supraorbital craniotomy (15 x 25 mm). Using this approach and an intraoperative endoscope for better visualisation of the aneurysmal neck, the authors operated on thirty-seven patients with forty intracranial aneurysms. There was no mortality, postoperative recovery was fast, and the cosmetic effect was excellent. Advantages and possibilities of this approach are discussed and results are presented. The authors recommend this approach as a minimal invasive surgery procedure in the treatment of intracranial aneurysms. When performed by experienced vascular neurosurgeons this approach is neither more difficult for the surgeon nor more dangerous for the patient than any other standard craniotomy procedure. According to the authors' present results, surgery of intracranial aneurysm via an eyebrow keyhole approach is the method of choice when performed by an experienced vascular neurosurgeon.

We reviewed our experience with shunt implantation during two time periods. From June 1985 to December 1990, 201 children with hydrocephalus underwent 382 operations. Among these children 36 (18%) developed a proven shunt infection, with an incidence rate per procedure of 9.4%. As a result of this study, a new effective protocol for shunt procedures involving modifications to the perioperative (antibiotic prophylaxis) and intraoperative management (meticulous surgical technique, complete shunt revision) of children undergoing initial shunt implantation or revision was initiated. With this new protocol 75 children underwent a total of 112 procedures between January 1991 and December 1995. The incidence of shunt infection decreased, with a per patient rate of 8% and a per procedure rate of 5.3%. The majority of infections in our study were caused by Staphylococcus epidermidis, which was found in 22 (52.3%) patients.

Objective: To demonstrate the clinical course in a young female with gonadotroph adenoma causing ovarian stimulation. Patient and methods: Our patient was a 23-year-old woman with a history of oligomenorrhea who had previously undergone bilateral ovarian wedge resection owing to the clinical appearance of polycystic ovaries. Two years later, she sought treatment for headache, galactorrhea, history of spotting and lower abdominal distension. FSH, LH, b-LH, inhibin A and B, estradiol, prolactin (PRL), and bchorionic gonadotrophin (b-CG) were measured, and the responses of FSH, LH and b-LH to thyrotrophin-releasing hormone (TRH) were documented. Immunohistochemical analysis of the tumor tissue was performed after surgery. Five years after the trans-sphenoidal surgery, the patient again became oligomenorrheic. A large recurrent adenoma was diagnosed on CT one year later. Transvaginal ultrasound showed ovaries of normal size with multiple small cystic formations simulating a polycystic pattern, While the patient was awaiting surgery, a pituitary apoplexy occurred. Emergency decompressive surgery was performed and the patient fully recovered. Results: Enlarged ovaries were found on ultrasound examination simulating a hyperstimulationlike pattern. At that time, elevated levels of FSH (13.4 IU/l) and marginally elevated levels of b-LH (1.43 ng/ml) were found, whereas the level of LH (0.5 IU/l) was subnormal. Plasma estradiol was markedly supranormal (6150 pmol/l). Levels of inhibin A and B were elevated (326 pg/ml and 588 pg/ml respectively). The prolactin level (70 ng/ml) was increased, whereas b-chorionic gonadotrophin (b-CG) was normal. Signi®cantly increased FSH, LH, and b-LH responses to TRH stimulation were documented. Pituitary macroadenoma was found on MRI scan and removed by trans-sphenoidal surgery. Immunohistochemical examination showed high positivity for b-CG and LH, and slight positivity for FSH. Five years after the surgery, estradiol was elevated (1160 pmol/l), whereas basal levels of LH (4.65 IU/l) and FSH (3.98 IU/l) were not suppressed. After the second operation, immunostaining of the adenoma tissue con®rmed the previous ®ndings. Conclusions: Measurement of gonadotrophins in our case did not prove to be a method for identifying a large recurrent gonadotroph pituitary adenoma. The sonographic ovarian imaging varied from a polycystic-to an ovarian hyperstimulation-like pattern during the evolution of the tumour.