BACKGROUND: To report the authors' experience with recurrent aneurysms after primarily completely clipped cerebral aneurysms and discuss mechanisms of recurrence and recommended management.METHODS: Data were available for 1016 consecutive patients who underwent clipping of ruptured and unruptured aneurysms in a 15-year period from 1993-2007.RESULTS: Nine patients were treated for recurrent aneurysms after successful complete clipping of the initial aneurysms; six patients had initial surgery before 1992, and three patients underwent surgery during the study period. Mean elapsed time between the first clipping and the recurrence of aneurysm was 13.3 years +/- 7.8. Repeat craniotomy was performed in seven patients, and six patients underwent reclipping of aneurysms with or without removal of the old clips. One patient was treated by construction of an extracranial-intracranial (EC-IC) bypass plus coating of the aneurysm. Endovascular occlusion of the parent artery was performed in one patient. One patient died without any intervention. Recurrent aneurysms could be classified into three types according to the relationship of the new aneurysm neck to the old clip.CONCLUSIONS: The incidence of recurrent aneurysms after complete clipping was approximately 0.02% per year; aneurysms recurred after 13.3 years on average with 25 years the longest duration from initial clipping to recurrence. Classification of recurrent aneurysms into three types might be helpful in selecting appropriate surgical management.

Patients sustaining severe trauma are at high risk for the development of venous thromboembolic events (VTE). Pharmacologic VTE prophylaxis may be contraindicated early after trauma due to potential bleeding complications. The purpose of this study was to evaluate safety and feasibility of early prophylactic vena cava filter (VCF) placement and subsequent retrieval in multiple injured patients with traumatic brain injury (TBI).

We report a case of meningioma diagnozed 23 years after high-dose cranial and whole-body irradiation for the treatment of acute lymphocytic leukemia (ALL). Radiotherapy in this case also caused early radiation injury to the lenses and the pituitary gland, with growth retardation and mineralizing angiopathy. Radiation-induced meningiomas are more commonly malignant, more commonly multiple, and more likely to recur after resection than non-radiation-induced meningiomas. Survivors of childhood ALL treated with high-dose cranial irradiation are at risk both for early radiation injury in radiosensitive organs, such as the lens and pituitary gland, and for the later development of a radiation-induced meningioma.

OBJECTIVE:To test the convenience of a new cooling technique with intravenous heat exchange catheters.DESIGN:Retrospective chart review.SETTING:University hospital neurointensive care unit.PATIENTS:Twenty patients with severe subarachnoid hemorrhage Hunt and Hess Grade 3-5 treated with mild hypothermia.INTERVENTIONS:Cooling to reach target body core temperature (33 degrees C-34 degrees C) was induced as quickly as possible in all patients. In the first ten patients (group one) moderate hypothermia was induced and maintained using cooling blankets. In group two, an 8.5F heat exchange catheter was placed central venous and temperature-adjusted normal saline circulated in a closed-loop system entailing two balloons.MEASUREMENTS AND RESULTS:A total of 2,007 values of body core temperature (BCT) were registered every hour. Foley temperature catheters were used for monitoring BCT in the bladder. The time to reach the target BCT and the stability of temperature during hypothermia were compared between the two groups. No specific complications associated with the new cooling device were observed. Time to reach the target temperature in group two was significantly shorter than in group one (190+/-110 and 370+/-220 min) ( P=0.023). In group one significantly more temperature values were out of the target range (127 of 792 values; 16.0%) than in group two (62 of 1,215 values; 5.1%) ( P<0.0001).CONCLUSIONS:The new endovascular cooling technique seems to be superior for rapid induction of hypothermia and maintaining a more stable temperature than the cooling techniques using blankets and ice bags.

around the tentorial notch may be gained by occipital interhemispheric, subtemporal, or temporal transventricular approaches. Each approach carries its own inherent risk of compromising visual fields and/ or language function (when performed in the dominant hemisphere) because of the need for retraction or cortical incision. The SCTT approach was devised to avoid these risks and was originally reported, as far as we can determine from our review of the literature, by Voigt and Yasargil20 in 1976 for removal of a cavernous angioma in the left parahippocampal gyrus. In this communication we describe our experience in using the SCTT approach to structures such as the posterior hippocampal formation and the PCA (P2 and P3 segments), which does not place these highly important functional areas at risk. Clinical Material and Methods

It should never be forgotten that there is far more to microsurgery than the mere possession of a highly perfected optical instrument. Without bipolar coagulation, specialized instruments, and, above all, knowledge and skill in atraumatic microtechniques, the microscope alone is of little value. Perfection of atraumatic microsurgical technique is best acquired by operating on small-diameter blood vessels (0.8 mm to 1.5 mm) in animals.

Barbiturate coma is initiated in brain-injured patients whenever elevated intracranial pressure remains unresponsive to other therapeutical strategies. However, barbiturates alter cortical activity resulting in difficulties in clinical evaluation. Therefore, we investigated the impact of long-term thiopental administration on responsiveness to exteroceptive stimuli in relation to pharmacokinetics of thiopental in CSF and serum. Long-term infusion increases thiopental levels which remain elevated for 6 and 9 days in CSF and serum, respectively, after termination of its administration. Prolonged unresponsiveness to exteroceptive stimuli correlates with persisting thiopental in CSF and serum. Thus, quantitative analysis of thiopental in serum becomes indispensable in predicting the length of drug-induced neurological impairment and in avoiding misinterpretation of the neurological status.

End-to-end carotid artery anastomoses and aorta arteriotomy closure in rats have been performed using a diffraction limited semiconductor MOPA laser, coupled to an operating microscope and emitting a 1 watt continuous power output at a wavelength of 985 nm. Laser aiming was performed using an eye-guided laser targeting prototype, which allows the user to direct the laser with a beam steering unit controlled by the surgeon's eye movements. Preliminary results show that efficient welds can be obtained with the MOPA laser with irradiances of 670 and 1195 W/cm2. The ease and efficiency of the eye-guided procedures enabled the user to close up to 5 mm long arteriotomies in the rat aorta and to accurately perform laser assisted microvascular anastomoses of rat carotid arteries These laser welding procedures demonstrate the feasibility of eye-guided laser targeting in laser microsurgery.

Physiologists have devoted most attention in the cerebrovascular tree to the arterial side of the circulation which has been subdivided in three levels: 1) major brain arteries which keep microcirculation constant despite changes in perfusion pressure; 2) pial arteries supposed to be effectors regulating microcirculation; 3) intracerebral arteries supposed to be deprived of active cerebral blood flow regulating devices.The morphological search for microvascular effectors in the cerebrovascular bed has been elusive. The opaque substance of the brain confines in vivo investigation to the superficial pial arteries. Most morphologists had to limit their observation to the random occurrence of a favorable site in the practically two-dimensional thickness of diaphanized histological sections. It is then not surprising most investigators of the cerebral microcirculation refer to an homogeneous network of microvessels interposed between arterioles and venules.We have taken advantage of the excellent depth of focus afforded by the scanning electron microscope (SEM) to investigate corrosion casts obtained injecting a range of experimental animals with a modified Batson's acrylic mixture.