Endoscopic Training Model for Intranasal Transsphenoidal Hypophysis Surgery Using a Skull Model and Chicken Wings.

AIM: To evaluate the feasibility of an experimentally designed model for training on endoscopic intranasal transsphenoidal hypophysis surgery. MATERIAL AND METHODS: In this experimental study, a surgical training model for endoscopic transsphenoidal hypophysis surgery was designed to simulate real life surgical challenges, such as drilling through the sella turcica under endoscopic vision. This laboratory experiment was repeated at 1-week intervals and it was observed that surgeons improved their skills. The compatibility of the training model was evaluated as either poor, acceptable or perfect. RESULTS: The results revealed that according to earlier data, greater success occurred in tests conducted after 1 week. Three new specialist neurosurgeons also expressed that their self-confidence increased during the second procedure. CONCLUSION: This laboratory study will result in improved use of microsurgical instruments and understanding of the threedimensional surgical field, as well as the development of manual dexterity. We believe that this model will contribute to the practical training of endoscopic hypophysis surgery.

Lumbar Juxtafacet Cysts.

AIM: To evaluate the factors affecting the clinical and radiological findings of juxtafacet cyst patients. MATERIAL AND METHODS: Between January 2011 and December 2018, eight patients diagnosed with juxtafacet cyst were reviewed, retrospectively. Patient demographics; signs and symptoms; and neurological examination, radiological, and surgical findings were noted. RESULTS: The mean age was 54 years (range, 34â€"69 years) with five (62.5%) females and three (37.5%) males. There were nine juxtafacet cysts in eight patients. Five cysts (55.5%) were located at the L3â€"L4 level, two cysts (22.2%) at the L4â€"L5 level, and two cysts (22.2%) at the L5â€"S1 level. In all patients with L3â€"L4 cysts, the intercrest line was intersecting the spinal column at L4 vertebral body level. The most frequent symptoms were back pain and radiculopathy. Magnetic resonance imaging and computerized tomography revealed degenerative facet arthropathy in six patients (75%). Three patients (37.5%) had a medical history of trauma. One patient (12.5%) was treated conservatively. Seven patients (87.5%) were advised to undergo surgical treatment. CONCLUSION: Degeneration and instability are the main causes of juxtafacet cysts. They are mainly seen at the L4â€"L5 level due to higher movement capacity of this level. But, if the intercrest line intersects the spinal column at higher levels, degeneration and instability risks move to upper levels, and juxtafacet cysts may occur at the L3â€"L4 or upper levels.

The Microneurosurgical Training Model for Intrinsic and Extrinsic Brain Tumor Surgery Using Polyurethane Foam and Fresh Cadaveric Cow Brain: An Experimental Study.

OBJECTIVE: To evaluate the feasibility of an experimentally designed brain tumor model consisting of polyurethane foam and fresh cadaveric cow brain for the surgical training of the technique for tumor ablation. METHODS: A laboratory-training model was created for microneurosurgical intervention of intrinsic brain tumor ablation covering microdissection of the brain tissue and opening of the pia mater, dissection and separation of the sulcal and cisternal structures, and dissection and removal of the tumor tissue. The left front parietal lobe was used as the area of interest for this experimental study. One-centimeter cube polyurethane foam was injected 2-cm deep inside the brain tissue using a plastic injection tube. After 5 minutes, the model was ready to use under the operating microscope for dissection, separation, and removal of the tumor tissue. The compatibility of the training model also was evaluated as poor, acceptable, and perfect. RESULTS: Ten stripped fresh cadaveric cow brains were used in this experimental feasibility study. The compatibility of the model was evaluated as poor, acceptable, and perfect in 1, 6, and 3 subjects, respectively. CONCLUSIONS: In intrinsic brain tumor ablation, surgical manipulations of sulcal, cisternal, and fissural dissection must be undertaken while preserving vital neural and vascular structures. We believe that our model holds promise in developing the technical skills of neurosurgeons in training.

Histopathological evaluation of mesenchymal stem cells in the healing of anastomosed carotid arteries.

The objective of this study was to evaluate the influence of mesenchymal stem cells on the healing of experimental carotid artery anastomoses histopathologically. Twenty-four female Sprague-Dawley rats were used in this study. After random separation of the subjects into two groups, in both groups carotid arteries were transected and anastomosed in end-to-end fashion. Anastomoses were locally treated with 1 ml 0.09% NaCl, and 1 ml mesenchymal stem cell suspension (1×106 cells) in control and trial groups, respectively. Anastomoses were wrapped with an 8 mm sheet of surgicel and soaked with BioGlue in order to sequestrate the stem cells. After patencies were confirmed via Doppler USG, surgical site was closed with 2/0 silk sutures. Histopathological evaluation was carried out after 4 weeks. In respect to endothelial continuity, vessel patency (along with presence or absence of restenosis), integrities of internal and external elastic laminae, muscularis and adventitia; no statistically significant differences were present between the trial and control groups. In Trial and Control Groups, luminal thrombus was present in 8 (66.6%) and 3 (25%) of the 12 subjects, respectively. The difference was statistically significant (P < 0.05). Recanalization was present in 6 subjects in trial group; 1 subjects in Control Group, respectively. Our results suggest that local administration of mesenchyme stem cell does not have a positive influence on success of an anastomosis.

Difficulties of Distal Catheter Insertion of Ventriculoatrial Shunting in Infants and Little Children.

AIM: Ventriculoatrial (VA) shunting is a well-described cerebrospinal fluid diversion method for the treatment of hydrocephalus. However, it may be very challenging in infants and little children because of atrial catheter placement difficulties. This study aimed to create an algorithm to solve problems faced during open surgical procedures based on the present authors' experience. MATERIAL AND METHODS: We conducted a retrospective analysis on 18 infants and children who underwent VA shunt insertion at the Department of Neurosurgery, Ondokuz Mayis University School of Medicine Hospital between 2005 and 2012. Complications, clinical outcomes, revisions, and solutions for overcoming distal catheter placement difficulties were evaluated. RESULTS: Twenty-six VA shunt operations were performed in 18 patients. Six patients required eight VA shunt revisions. VA shunting was primarily performed from the internal jugular, facial, cephalic, and subclavian veins to the right atrium. In revision procedures, the internal jugular, cephalic, and subclavian veins were used. CONCLUSION: VA shunting in infants and little children requires careful surgical techniques. Neurosurgeons should necessarily have an appropriate strategy for VA shunting considering the complications and revisions. Our results suggest open surgical solutions to overcome distal catheter placement difficulties in this age group.

Electrophysiological and histopathological effects of mesenchymal stem cells in treatment of experimental rat model of sciatic nerve injury.

AIM: The aim of this study was to evaluate electrophysiological and histopathological effects of mesenchymal stem cells in treatment of sciatic nerve injury. MATERIAL AND METHODS: Thirty-two female Spraque-Dawley rat were used in this study. Eight rats were used as a reference group in electrophysiological analysis for evaluation of non-injured nerve recordings (Control Group). Twenty-four rats were used for experimental evaluation. Twelve rats were anastomosed without treatment with mesenchymal stem cells (Sham Group) and twelve other rats were anastomosed and treated with mesenchymal stem cells (Stem Cell Group). Surgicel and bioglue were used in anastomosed line in both Groups. Eight weeks after the surgery, electrophysiological evaluation of rats was performed and, then, rats were decapitated under anesthesia and specimens including sciatic nerves and anastomosed line were taken for histopathological evaluation. Electromyography and nerve conduction velocity testing and histopathological scoring including rate of Wallerian degeneration, and neuroma and scar formation were evaluated for both Groups. RESULTS: There were no statistically significant differences between Sham and Stem Cell Groups with respect to histopathological evaluation. However, nerve conduction velocity showed significant difference between groups (P = 0.001). Nerve conduction velocity was significantly improved in Stem Cell Group when compared to Sham Group. CONCLUSION: In this study, based on nerve conduction velocity data, it was concluded that treatment with mesenchymal stem cells during end-to-end anastomosis improves functional regeneration.

Shoulder traction device for enhanced conventional fluoroscopy during cervical spine operations.

Conventional biplanar fluoroscopic imaging of the cervical spine is commonly used during cervical spinal surgery. We designed an intraoperative traction device to prevent shoulder superimposition on the cervical fluoroscopic imaging. During surgery at the stage of fluoroscopic examination, an operator can apply traction via the traction band of the device. This device is safe and easy to use, and can be preoperatively fitted to patients. Fluoroscopic images obtained with the new traction device were definitely superior compared with images obtained without the traction device. This device may be useful in cases with difficult fluoroscopic imagination of the lower cervical spine.

Use of topical landmarks for percutaneous projection of intracranial tumors for neurosurgical oncology.

AIM: The objective of this study was to introduce a surgical navigation method which provides a safe, quick and effective access to cortical and subcortical tumors, along with a review of other methods in use for this purpose. MATERIAL AND METHODS: 53 patients have been operated using this technique. The area overlying the tumor is shaved and one half of a smoothly cut hazelnut is taped on the skin. The precise localization of the hazelnut is confirmed with MRI and then stained. After general anesthesia, the stained impression is projected firstly to the bone, dura and then cortex respectively by the Midas Rex cutting tip. Cortical landmarks surrounding the tumor's cortical projection are further confirmed with ultrasonography. RESULTS: After removal, cortical and subcortical tumors were separately graded for efficiency. Grade 1 and 2 were accepted as precise access. Our method accordingly yielded 95.2% and 90.6% success rates for cortical and subcortical tumors respectively. CONCLUSION: Considering the method's success rate along with its inexpensiveness and modest technical requirements, it is believed that this method can be of widespread use.