Band 2, Heft 1-4

Purpose: We report the effectiveness of a new strategy for ventricular cannulation that allows for easy insertion into the firm ventricular wall. Method: The new ventricular needle consisting of an outer needle, a dull inner needle, and a sharp inner needle was used for a firm ventricular wall tap in five patients. The dull inner needle was used for the brain mantle tap, whereas the sharp needle was used for penetrating the ventricular wall. The outer needle with the insertion of the dull inner needle was set for initial puncture. If the operator felt that the ventricular wall was firm or confirmed that the tip of the cannula indented the wall of the ventricle using real-time ultrasound monitoring before penetrating the ventricle wall, then the inner needle was changed to the sharp one to penetrate the ventricular wall. After confirming that the trajectory was now passing into the ventricle, the ventricular catheter was placed using the trajectory. Result: There was no perioperative complication associated with insertion of the device. All catheters were inserted with a single pass through the brain mantle. Conclusion: The new ventricular tap strategy is safe and effective for firm ventricular wall tap and ventricular catheter insertions.

Objective: The aim of our study was to investigate the detailed endoscopic anatomy of the intracisternal portion of the oculomotor nerve and to update the present knowledge of its related anatomy with the newest research on the topography of the arachnoid membrane system of the skull base. Methods: This study was performed on 50 fresh human cadaveric specimens post-mortem not more than 72 h. In each specimen, the intracranial arterial system was injected with red gelatin solution. We used the endoscope-controlled and endoscope-assisted microsurgical techniques applied through the minimally invasive supraorbital keyhole craniotomy to perform our dissections. Results: We divided the intracisternal oculomotor nerve into three segments in this study. These are the interpeduncular segment, located in the interpeduncular fossa and surrounded by dens arachnoid trabeculae around the thalamoperforating arteries; the tentorial segment, located between the posterior cerebral and superior cerebellar arteries and the posterior petroclinoid fold and surrounded by the elements of the clival and tentorial arachnoid membrane groups; and the trigonal segment located on the surface of the oculomotor trigone between the posterior petroclinoid fold and the dural exit of the nerve into the cavernous sinus and surrounded by the posteriorly located membranes of the carotid membrane group. Conclusions: Our findings support the more accurate understanding of the physiology of the arachnoid membrane system and the pathophysiology of space-occupying lesions in the region of the oculomotor nerve. Therefore, our results may support performing more atraumatic surgery in this area.

Background: Spinal cord stimulation has been in use for decades and is growing as a therapeutic treatment option. A significant problem arising from the epidural location of the lead is electrical shunting through the cerebrospinal fluid, providing sub-optimal delivery of the electrical current specifically to the Aβ fibers of the dorsal column. Objective: Our goal is to design a safe and effective intradural spinal cord stimulator (SCS) that places the stimulating electrodes directly against the pia similar to what is currently employed with the auditory brainstem implant. Methods: We have reviewed the literature on the early original intradural SCSs and designed, built, and tested an improved device that seeks to overcome the limitations the existing epidural stimulators. Results: In particular, we have shown that the present design of our device allows for motion of the spinal cord without the device being displaced itself, exerts a surface pressure on the spinal cord surface that is below what would cause ischemia or vessel injury, activates somato-sensory evoked potentials at a lower threshold than epidural stimulation, and (iv) does not cause deleterious neurological deficits in a chronic ovine model of intradural stimulator implantation. Conclusion: While further studies to prove long-term safety and durability of the device are underway, we believe that revisiting an intradural approach to spinal cord stimulation may continue to improve our ability to treat certain chronic pain states and possibly the spasticity associated with spinal cord injuries.

Traumatic spondylolisthesis of C2 occurs when the mechanical event at the base of the trauma is a compression force on the vertex. Management of this is well defined in literature, and both surgical and conservative treatments have been proposed in adults. In contrast, the principles of treatment are somewhat more uncertain and less well defined in children. One of the most frequently suggested treatments is the early reduction of the fracture, with immobilization in halo. Other types of cervical orthoses are not recommended. This article reports on a rare case of an inveterate hangman’s fracture in a 12-year-old girl that is healing completely through immobilization in a SOMI brace that was applied 4 months after the trauma. In our experience, hangman’s fracture is poorly defined with regard to the treatment of pediatric patients, and there are currently no established guidelines. If dynamic X-ray scans show complete reduction of the fracture, conservative treatment is an efficient, effective, and noninvasive solution, even in case of inveterate fractures. Halo vest and SOMI brace are good solutions. SOMI brace is an available option because it is less traumatic for the patient.

Pediatric intracranial aneurysms are a rare entity, with an often reported prevalence ranging from 0.5% to 4.6%. Their etiology is poorly understood; however, their association with other congenital disorders, such as polycystic kidney disease and Marfan syndrome, has been widely documented in the pediatric neurosurgical literature. We present a case of a 9-month-old boy with tuberous sclerosis with a giant cavernous internal carotid artery aneurysm presenting with third nerve palsy.

Background: Advances in neurosurgery have allowed for more sophisticated mapping of various eloquent neural structures including the visual cortex. Applications of various modalities of new technologies allow accurate brain mapping for neurosurgical planning and preservation of functions in patients with lesions involving the eloquent cortex. The authors demonstrate the use of various new technologies for accurate presurgical planning, preservation of brain functions, and depiction of patterns of cortical brainwaves, which relate to motor networks and continuous visual stimuli. Methods: A patient with a right periatrial lesion involving the optic radiation with no visual field deficits was operated under an awake state and under continuous contralateral electrocorticography and visual monitoring. Presurgically, extra-operative brain mapping for visual-, sensory-, and motor-evoked magnetic fields were completed using magnetoencephalography (MEG). The dipole areas were identified, and the images were fused with a 116-region cortical brain atlas. The ideal trajectory was planned based on these images and diffusion tensor imaging (tractography). The trans-sulcal approach via the inferior parietal lobule was elected. Prior to resection, intra-operative stimulation and mappings were done and continuous visual-evoked potentials were monitored during the actual resection. Results: A good agreement for eloquent areas was identified based on extra-operative MEG and intra-operative neurostimulation mappings. The patient had no new neurological or visual-field deficits after the surgery. Certain patterns of brainwaves for motor cortex and visual stimulation were obtained: (a) spikes at the contralateral sensorimotor area when the motor strip was stimulated and (b) up-down and dense-loose continuous visual-evoked brainwaves at the occipital pole toward flashing checkerboard visual stimulation. Conclusions: A combination of extra- and intra-operative brain mappings should ideally be done in patients harboring lesions near eloquent areas. The continuous visual-evoked potential monitoring, using a grid electrode and flashing checkerboard and contralateral sensorimotor responses, observed in our case is interesting and needs further studies.