Modified Tap-drilling Technique for Mid-cervical Pedicle Screw Placement: A Case Series of 473 Consecutive Screws.

STUDY DESIGN: Retrospective cohort study. OBJECTION: To report our modified tap-drilling technique for mid-cervical pedicle screw placement and to evaluate its safety and accuracy. SUMMARY OF BACKGROUND DATA: Cervical pedicle screw fixation, which provides a strong stabilization, has been a major concern due to the potential risks to neurovascular structures despite its increasing use. Several insertion techniques have been described so far to improve the cervical pedicle screw placement accuracy. METHODS: This study retrospectively reviewed patients who underwent mid-cervical (C3-C6) pedicle screw fixation between September 2005 and September 2020. Laminectomy, laminoforaminotomy, or notch-referred anatomic landmark methods were used to adjust the entry point and the direction of the screws. After the cortical bone was removed at the entry point with a diamond burr, the cancellous bone was slowly drilled with a hand drill starting from 8 to 10 millimeters in length. Then, all of the bone walls were checked with a ball-tip probe to determine if there was any breach. The procedure was repeated several times. After completing the drilling, the screw was inserted without tapping. The breach rate of pedicle screws was analyzed on postoperative computed tomography scans. RESULTS: A total of 473 mid-cervical pedicle screws were placed in 122 consecutive patients. No navigation or computer-assisted system was used, and the first 2 authors inserted all of the screws. All patients completed the surgery, and no evident intraoperative complications occurred. Postoperative CT scans were obtained for 405 screws. Although deviation was observed for 131 pedicle screws, a critical deviation was observed for only 25 pedicle screws. CONCLUSIONS: Cervical pedicle screw insertion is a risky but applicable technique. Checking all of the bone walls with a ball-tip probe before gradually advancing the hand drill in small amounts, as presented in this article, may lead to the safe and effective placement of cervical pedicle screws.

A case of rare lumbar intradural tumor: paraganglioma.

Lumbar paragangliomas are rare neuroendocrine neoplasms arising from specialized neural crest cells in the cauda equina/filum terminale region. They are difficult to diagnose radiologically and can be difficult to treat surgically if they secrete catecholamines. A 38-year-old woman presented with three and a half years of increasing lower back and sacrum discomfort. Her neurological examination was normal. The MRI revealed an L4 intradural lesion that was compressing the cauda equina. A total tumor resection was conducted. The paraganglioma was diagnosed by the pathology report. Paragangliomas should be considered in the differential diagnosis of intradural masses of the lumbar spine.

Dexamethasone Addition Impairs the Therapeutic Effects of Nimodipine for Subarachnoid Hemorrhage: An Experimental Animal Study.

AIM: To evaluate the effects of the combination of nimodipine and dexamethasone in subarachnoid hemorrhage (SAH). MATERIAL AND METHODS: In this study, 35 female adult Wistar Albino rats were randomly assigned to four groups: Sham (n=8), SAH with no treatment (n=9), SAH with nimodipine (n=9, oral gavage, 12 mg/kg, BID) treatment, and SAH with combined therapy with nimodipine and dexamethasone (n=9, intraperitoneally, 1mg/kg, BID). The "cisterna magna double injection of autologous blood" model was used. The animals were euthanized 5 days after the first injection. RESULTS: Of the total, five rats died before euthanasia. The SAH+Nontreatment group showed the worst score in neurological examinations, and the most severe histopathological findings were noted in terms of vasospasm. The SAH+Nimodipine group showed the best neurological score and the closest histopathological results to those of the Sham group, whereas adding dexamethasone to nimodipine treatment (the SAH+Nimodipine+Dexamethasone group) worsened the neurological and histopathological outcomes. CONCLUSION: We thus concluded that the therapeutic effects of nimodipine were impaired when combined with dexamethasone. We thus hypothesized that dexamethasone possibly induces the CYP3A4-enzyme that metabolizes nimodipine. However, it should be noted that our results are based on laboratory findings obtained on a small sample, therefore further studies with drug-drug interaction on a larger sample size through CYP3A4-enzyme and clinical confirmation are warranted.

Women in Neurosurgery: Turkey's Yildiz Yalçinlar.

BACKGROUND: Severalreports have been published on the history of pioneering women pursuing neurosurgery. Women in Turkey started receiving neurosurgery specialty training later than men, as was the case in other parts of the world. However, compared to other countries, Turkey saw the admission of women in neurosurgery sooner, with Aysima Altinok who obtained her specialization in 1959. Nevertheless, Yildiz Yalçinlar, one of the pioneers, remains relatively unknown. METHODS & RESULTS: In this paper, we witness Yildiz Yalçinlar's journey, from her graduation from Ankara Medical Faculty in 1954 and her subsequent specialization in general surgery to her arrival in Igdir as a young surgeon in the early 1960s, where she faced cultural challenges. We explored her transition into neurosurgery, becoming the second neurosurgeon in Turkey in 1965. We examine her complex career progression from receiving her specialization in neurosurgery to her academic journey toward becoming a department chief and her role as one of the founding members of the Turkish Neurosurgery Association. CONCLUSIONS: In Turkey, the number of women practicing as neurosurgeons has increased consistently. Despite this upward trend, the representation of women in the field of neurosurgery remains disproportionately low. We hope that Yildiz Yalçinlar's achievements, which began in the early 60s, will encourage women today and contribute to the continuing growth of neurosurgery.

A True Percutaneous Anterior Odontoid Screw Fixation: The Results of 42 Cases by a Single Surgeon.

OBJECTIVE: This study aimed to analyze a clinical series of odontoid fractures treated with true percutaneous anterior odontoid screws. The technique we used is different from the traditional approach of using blunt dissection to arrive at the anterior surface of the vertebral body. METHODS: Between 2004 and 2021, forty-two patients underwent anterior screw fixation of the odontoid process using the true percutaneous technique without dissection among the fascial planes. Instead, we pressed from the medial border of the sternocleidomastoideus muscle with our second and third fingers to feel the vertebrae under the skin. Thus, the carotid artery is pushed laterally, the trachea-esophageal complex is moved medially, and when no esophagus, great vessels, etc., can be felt under our fingers; we have reached the anterior surface of the spine. Advancing the Jamshidi needle between the fingers causes it to pass only through the fascial layers. The absence of a gap between the dilatation tubes prevents any tissue from escaping into the tubes. RESULTS: We had no intraoperative complications, such as esophageal, tracheal, or carotid injury. One patient required screw revision. In total, 5 patients died during the follow-up period, and 3 were lost to follow-up. There was no residual neck pain in our cohort, and no instability was noted on flexion-extension radiographs, even in ten patients without solid bone fusion. CONCLUSIONS: True percutaneous anterior odontoid screw fixation is a safe and reliable procedure for treating odontoid fractures. The fibrous union of odontoid fractures provides as much stability as a solid bone fusion.

Evaluation of Incidentally Detected Pathology Results of Patients with Vertebral Fracture Treated by Vertebroplasty and Kyphoplasty: A Retrospective Study.

BACKGROUND: Vertebroplasty and kyphoplasty are minimally invasive techniques used to treat vertebral compression fractures. The etiology of vertebral compression fractures varies among patients. Although osteoporosis and trauma are major etiologic factors in patients with a vertebral compression fracture, unexpected results were found in 11 patients in the present study. The aim of the present retrospective study was to determine the incidentally detected pathology results of patients with vertebral fracture treated by vertebroplasty and kyphoplasty. METHODS: From February 2010 to November 2015, 616 patients with a vertebral compression fracture were treated by kyphoplasty and vertebroplasty at our institution. Vertebral biopsies were obtained from 533 patients during a vertebral augmentation technique. The average patient age was 62.4 years. Of the 616 patients, 388 were female and 228 were male. Histological evaluation of the biopsy specimens from the vertebral compression fractures was performed. RESULTS: The biopsy results of 505 patients showed various stages of bone healing. Among these patients, malignancy was identified in 23 patients, and 43 patients had a history of malignancy. In 6 patients, an unsuspected malignancy was found, and 1 patient had Paget's disease. Infection was detected in 4 patients. In our study, the rate of unsuspected malignancy was 1.1%. CONCLUSIONS: Tissue examination is useful and could reveal pathologic fractures. An incidentally detected biopsy result could change the treatment of patients; however, bone biopsy should be reserved for those patients whose preoperative radiological diagnosis raises suspicion of a nonosteoporotic etiology.

Double-layer appearance after evacuation of a chronic subdural hematoma.

OBJECTIVE: To investigate the reason for and the course of the double-layer appearance in the postoperative computed tomographies (CTs) of chronic subdural hematoma (CSDHs). METHODS: We reviewed CSDH cases that were operated on during the last 3 years, between January 2008 and December 2010. We checked the preoperative, early postoperative, and late postoperative CTs of these patients. We investigated the relationship between the formation of a double-layer appearance and the prognoses and demographic characteristics of the patients. RESULTS: Our database included 119 cases. A double-layer appearance was found in the postoperative CTs of 34 cases. The mean age of double-layer cases was older (72.5 ± 12.1) than that of the remaining 85 cases (63.1 ± 17.8). We did not find any relationship between the double-layer appearance and the reoperation/recurrence/death rates. CONCLUSIONS: The double-layer appearance after evacuation of a CSDH might be caused by enlargement of the subarachnoid space and is not related to the presence of any residual hematoma. This appearance is not considered as a reason for reoperation.

Prevention of anterior scar formation following discectomy with a MediShield adhesion barrier: randomized experimental trial.

AIM: To investigate whether carboxymethylcellulose/polyethylene oxide (CMC/PEO) gel has a protective effect against epidural scar formation anterior to the dura following discectomy. MATERIAL AND METHODS: A barrier gel comprised of CMC and PEO (MediShield) was studied as a material to reduce anterior epidural scar formation in a rabbit laminotomy and discectomy model. After laminotomy and disc puncture, the surgical side was either treated with MediShield or used as a surgical control, as determined by random allocation. Two months after surgery, the animals were euthanized, and their lumbar spines were removed in an en bloc excision for pathological evaluation. Scar formation was evaluated as present or absent. RESULTS: The MediShield group contained 12 rabbits, and the control group contained 7 rabbits. Epidural fibrosis was observed in two out of twelve specimens (17%) in the MediShield group and in three of seven (43%) cases in the control group (P=0.305, Fisher's Exact Test). CONCLUSION: Though it was not statistically significant, we observed a difference between the MediShield and control group that favored the MediShield group. The application of the CMC/PEO gel might protect against epidural fibrosis after lumbar discectomy, but its efficacy needs to be investigated in larger experimental trials.

Brucellar spondylodiscitis: comparison of patients with and without abscesses.

Brucellosis is an important cause of spondylodiscitis in endemic areas. Brucellar spondylodiscitis is a serious complication because of its association with abscess formation. Prospective studies comparing patients with and without abscesses are lacking. The objective of this study was to determine the frequency and demographic, clinical, laboratory, and radiological features of brucellar spondylodiscitis and to compare patients with and without abscesses regarding treatment and outcome. Out of 135 consecutive patients with brucellosis, 31 patients with spondylodiscitis were recruited for the study. Patients were grouped according to magnetic resonance imaging findings. The frequency of spondylodiscitis was 23.0 %. Sites of involvement were lumbar (58.1 %), lumbosacral (22.6 %), cervical (9.7 %), thoracolumbar (6.5 %), and thoracic (3.2 %). Abscesses occurred in 19 (61.3 %) patients and were associated with low hemoglobin levels. Medical treatment included a combination of streptomycin (for the first 3 weeks), doxycycline, and rifampin. The total duration of treatment was 12-39 (mean 17.0 ± 8.5 SD) weeks. By 12 weeks of treatment, evidence of clinical improvement (67 vs. 28 %) and radiological regression (92 vs. 50 %) was significantly greater in patients without abscesses. The duration of treatment was longer if an abscess was present. Two female patients with abscesses required surgical intervention. Both patients presented with high fever, neurologic deficit, and high Brucella standard tube agglutination test titers. Each patient should be evaluated individually, based on clinical findings, laboratory data, and radiological results, when undergoing treatment for brucellar spondylodiscitis. If abscesses are found, a longer course of treatment and even surgical intervention may be needed.

Partial spondylectomy for primary leiomyosarcoma of C2 vertebra.

STUDY DESIGN: A primary leiomyosarcoma located on the left side of the C2 is reported. Left-sided partial spondylectomy and anterior reconstruction with posterior stabilization was performed by a two-staged operation. OBJECTIVE: To emphasize the occurrence of primary leiomyosarcoma and the importance of proper stabilization in the upper cervical spine. SUMMARY OF BACKGROUND DATA: Leiomyosarcoma is a rare malignant neoplasm of the bone and the primary leiomyosarcoma of the spine is extremely rare. Radical tumor excision is the goal in case of vertebral leiomyosarcoma, but to both gain surgical access to the upper cervical spine and obtain anterior reconstruction is challenging. METHODS: Leiomyosarcoma of the C2 in a 25-year-old woman with mild neurologic deficits is reported. A left-sided partial spondylectomy of C2 was performed. The defect of the vertebral body was reconstructed by expandable titanium prosthesis, and posterior craniocervical fixation was performed by the polyaxial screws in the lateral masses and rod/plates. RESULTS: The surgical margin was very small. The pathology of the tumor was reported as leiomyosarcoma. No sign of local recurrence or metastasis was evident 1 year after surgery. CONCLUSION: Leiomyosarcoma, although rare, should be kept in mind as one of the possible diagnoses when a patient with an upper cervical tumor is presented and complete tumor removal must be the goal.

Nasal-subfrontal giant schwannoma.

Subfrontal schwannomas are rare lesions. They can be misdiagnosed as olfactory meningiomas or neuroblastomas. We report a case of giant schwannoma involving the anterior cranial fossa; the frontal and ethmoid sinuses and nasal cavities. The patient presented with a year-long history of increasingly severe headache associated with insomnia. Examination revealed no neurological deficit except for the anosmia. Magnetic Resonance Imaging revealed a 9x5x3 cm intranasal-subfrontal extraaxial mass. Nasal biopsy indicated the presence of a schwannoma. The lesion was totally removed through a bifrontal craniotomy and the skull base was repaired with periosteal flap, fibrin glue and a split craniotomy graft. In addition to the cosmetic advantages over standard transfacial approaches, the extended subfrontal approach also provides early dissection of neural tissues, avoiding an inadvertent cerebrospinal fluid leak.

Is it possible to start the treatment based on immediate cytologic evaluation of core needle biopsy of the spinal lesions?

Core needle biopsy is widely used to diagnose spinal lesions. Final histopathological report of the specimen usually can be given after several days. These several days delay may prevent early treatment in some patients. Our aim was to investigate if treatment of spinal lesions could be started according to the immediate cytologic evaluation of the core needle biopsy. The cytological materials of the 213 core needle spinal biopsy were prepared immediately after biopsy procedure. Of these biopsies, only 101 core needle biopsy had a final diagnosis which formed the backbone of the current study. Cytological materials of these cases were compared with both histopathologic results of the core biopsy and with final diagnosis obtained by open surgery or clinical follow up. According to final diagnoses 40 patients had infections, 59 patients had neoplasms and 2 patients had no pathology. When the diagnosis that determines the treatment is considered, the overall success rates (positive predictive value:PPV) of cytology and histology were 0.65 and 0.76 respectively. Moreover when the specific diagnosis were analyzed separetely in the subgroups of tuberculous infection, lymphoma and plasmacytoma; PPV of both cytological and histological assessments was 1.00. In spinal metastasis, PPV was 0.97 for cytology and 1.00 for histology. Rapid cytologic interpretation of core needle biopsy material is a useful and reliable tool to determine the spinal lesions which require urgent treatment. When the cytological specimen reveals the diagnosis of spinal metastasis, lymphoma, plasmacytoma or tuberculosis, the treatment may be started without waiting the result of the histological examination.

Hemifacial spasm in correlation with electrophysiological and radiological findings.

OBJECTIVE: To investigate the correlation between the electrophysiological and radiological findings of primary hemifacial spasm patients. SUBJECTS: Patients with primary hemifacial spasm who had had no botulinum toxin treatment previously were included in the study. DESIGN: In this prospective study patients underwent cerebral magnetic resonance imaging,a magnetic resonance angiography investigation and an electrophysiological examination after informed consent had be given by the patients. The facial nerve distal latency, amplitude and blink reflex responses were recorded as well as clinical and demographic data. RESULTS: Twenty five patients completed radiological and electrophysiological investigations. The radiological investigations disclosed neurovascular compromise which can cause hemifacial spasm in twelve patients (48%) while the findings of two patients were not considered as a certain cause of hemifacial spasm. All patients except two had at least one electrophysiological abnormality (92%). The most frequent finding was an increased R1/D ratio which suggested an increased central conduction time. CONCLUSION: In this study, an increased R1/D ratio suggests that there is a functional impairment in the brain stem even if it is not possible to disclose structural abnormalities in some hemifacial spasm patients. Combining magnetic stimulation may be a useful tool for further investigations. An inadequate radiological investigation might be the cause of relatively low radiological abnormalities in comparison with the electrophysiological ones.

Can midline brain shift be used as a prognostic factor to predict postoperative restoration of consciousness in patients with chronic subdural hematoma?

BACKGROUND AND PURPOSE: Our aim was to determine if midline brain shift could be used as a prognostic factor to predict postoperative restoration of consciousness in patients with CSDH. In these patients, we evaluated the relation (1) between midline brain shift as measured on CT and alteration of level of consciousness, and (2) between midline brain shift and restoration of consciousness after the operation. METHODS: Prospectively recorded data of 45 patients with CSDH were evaluated. We compared level of consciousness of patients measured by GCS score, brain displacement at PG and SP both in the preoperative and early postoperative period. RESULTS: Preoperatively, PG and SP shifts of the patients who were alert (GCS = 15) were significantly less than those of patients who had diminished consciousness. However, in patients with diminished consciousness (GCS < 15), the amount of lateral brain displacement and the degree of diminution of consciousness did not correlate. Those patients who had a preoperative SP shift of less than 10 mm had a significantly lesser chance to become alert after operation (2 of 5 patients) when compared with those patients who had a preoperative SP shift of 10 mm or more (21 of 23 patients). CONCLUSIONS: We conclude that preoperative SP shift may be used as a factor to predict restoration of consciousness in patients with CSDH; the likelihood of becoming alert after operation is increased if SP shift is 10 mm or greater, and is decreased if SP shift is less than 10 mm.

Percutaneous computed-tomography-guided biopsy of the spine: 229 procedures.

OBJECTIVES: Percutaneous biopsy of the spine is an effective and well-evaluated procedure. Only very few series containing more than a hundred patients have been reported so far and there is no agreement about the factors affecting the diagnostic rate. We aimed to find out if there is any factor influencing the success rate of the spinal biopsy using our biopsy series. METHODS: Two hundred and twenty-nine procedures were performed in 201 patients between November 2001 and August 2005. All procedures were performed under computed tomography guidance. The side was chosen according to the extension of the lesion. When the lesion was in the midline or extended to both sides, we preferred to obtain biopsy from the right side. The puncture point and the needle trajectory were planned on both lateral computed tomography scout scan and axial scans. RESULTS: We found that the diagnostic rate was not affected by the variables such as age, gender, type and diameter of the biopsy needle, diagnosis as well as lesion localization and level. The success rate of the repeat biopsies was considerably lower than the first procedures. CONCLUSIONS: The diagnostic rate is not affected by any of the variables but the approach, chosen can vary with the level, localization, and lesion characteristics.

Lumbar disk herniation with contralateral symptoms.

The aim of the study is to determine if leg pain can be caused by contralateral lumbar disk herniation and if intervention from only the herniation side would suffice in these patients. Five patients who had lumbar disk herniations with predominantly contralateral symptoms were operated from the side of disk herniation without exploring or decompressing the symptomatic side. Patients were evaluated pre- and postoperatively. To our knowledge, this is the first reported series of such patients who were operated only from the herniation side. The possible mechanisms of how contralateral symptoms predominate in these patients are also discussed. In all patients, the shape of disk herniations on imaging studies were quite similar: a broad-based posterior central-paracentral herniated disk with the apex deviated away from the side of the symptoms. The symptoms and signs resolved in the immediate postoperative period. Our data clears that sciatica can be caused by contralateral lumbar disk herniation. When operation is considered, intervention only from the herniation side is sufficient. It is probable that traction rather than direct compression is responsible from the emergence of contralateral symptoms.

The value of XYZ/2 technique compared with computer-assisted volumetric analysis to estimate the volume of chronic subdural hematoma.

BACKGROUND AND PURPOSE: A simple estimation method of intracerebral hematoma volume known as XYZ/2 method has been described previously. This method has also been shown to be valid for the estimation of acute subdural hematoma volume. However, chronic subdural hematomas differ in shape and extension from acute subdural hematomas, which makes the validity of the same method in the estimation of hematoma volume questionable. We aimed to determine the value of XYZ/2 method to estimate the volume of chronic subdural hematoma when compared with computer-assisted volumetric analysis. METHODS: Computed tomography scans of 28 patients with unilateral hemispheric chronic subdural hematoma were reviewed. Hematoma volumes were measured using 5 different XYZ/2 formulas and compared with volumes measured by computer-assisted analysis. Nonparametric correlation coefficient (Spearman's rho) was used in statistical comparison. RESULTS: All 5 formulas showed excellent correlation with the gold standard, proving the validity of XYZ/2 method in the estimation of chronic subdural hematoma volume (level of significance <0.001). Our results suggest that maximum hematoma length and width, which are not necessarily on the same slice, should be used rather than length and width of hematoma on the central slice when using XYZ/2 method in patients with chronic subdural hematoma. CONCLUSIONS: This study proves the validity of XYZ/2 technique for the estimation of chronic subdural hematoma volume as well.

Combined approach for otogenic brain abscess.

Otogenic intracranial infections usually require both neurosurgical and otolaryngological surgery. This prospective, non-randomized study investigated the value of combining both surgical procedures. Thirteen patients with otogenic intracranial abscess were treated by mastoidectomy and abscess removal through the same incision between 1993 and 2002. Another 12 patients underwent abscess removal or mastoidectomy followed by the other procedure within 7 days. The clinical features of the patients were compared. Four patients died in our series. All four patients had Glasgow Coma Scale (GCS) scores of 7 or less. The preoperative GCS score was the main factor in mortality. One patient had recurrence after the combined approach compared to nine patients with recurrence after separate procedures. The surgical procedure was the main factor affecting the recurrence rate. The combined approach and total capsule excision of the abscess may reduce the risk of recurrence of otogenic intracranial abscess.