Transmandibular Cervical Corpectomy for Persistent Spinal Cord Compression in a Patient With Klippel-Feil Syndrome: A Technical Note and Systematic Review.

BACKGROUND: Few studies have described a transmandibular approach for decompression in a patient with Klippel-Feil syndrome (KFS) for cervical myelopathy. OBJECTIVE: To describe the transmandibular approach in a KFS patient with cervical myelopathy and to perform a systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. METHODS: A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Embase and PubMed databases were searched from January 2002 to November 2022 for articles examining patients with KFS undergoing cervical decompression and/or fusion for cervical myelopathy and/or radiculopathy were included. Articles describing compression due to nonbony causes, lumbar/sacral surgery, nonhuman studies, or symptoms only from basilar invagination/impression were excluded. Data collected were sex, median age, Samartzis type, surgical approach, and postoperative complications. RESULTS: A total of 27 studies were included, with 80 total patients. Thirty-three patients were female, and the median age ranged from 9 to 75 years. Forty-nine patients, 16 patients, and 13 patients were classified as Samartzis Types I, II, and III, respectively. Forty-five patients, 21 patients, and 6 patients underwent an anterior, posterior, and combined approach, respectively. Five postoperative complications were reported. One article reported a transmandibular approach for access to the cervical spine. CONCLUSION: Patients with KFS are at risk of developing cervical myelopathy. Although KFS manifests heterogeneously and may be treated through a variety of approaches, some manifestations of KFS may preclude traditional approaches for decompression. Surgical exposure through the anterior mandible may prove an option for cervical decompression in patients with KFS.

Clinical and radiographic benefits of skipping C7 instrumentation in posterior cervicothoracic fusion: a retrospective analysis.

Background: C7 instrumentation during posterior cervicothoracic fusion can be challenging because it requires additional work of either placing side connectors to a single rod or placing two rods. Our clinical observations suggested that skipping instrumentation at C7 in a multi-level posterior cervicothoracic fusion will result in minimal intraoperative complications and decreased blood-loss while still maintaining sagittal balance parameters of cervical fusion. The objective of this study is to determine the clinical and radiographic outcomes of skipping C7 instrumentation compared to instrumenting the C7 vertebra in posterior cervicothoracic fusion. Methods: This is a retrospective chart review of 314 consecutive patients who underwent multilevel posterior cervical fusion (PCF) at our institution. Out of 314 patients, 19 were instrumented at C7 serving as the control group, while the remaining 295 patients were not. Evaluation of efficacy was based on intraoperative complications, operative time, estimated blood loss (EBL), significant long-term complications, and radiographic evidence of fusion. Results: Skipping the C7 level resulted in a significant reduction in EBL (488±576 vs. 822±1,137; P=0.007); however, operative time was similar between groups (174±95 vs. 184±86 minutes; P=0.844). Complications were minimal in both groups and not statistically significant. Radiographic analysis revealed C7 bridge patients had a significantly increased postoperative sagittal vertical axis (SVA) (29.3±13.1 vs. 20.2±3.1 mm; P=0.008); however, there was no significant difference between groups in SVA correction (-0.3±16.2 vs. -16.1±16.0 mm; P=0.867), T1 slope correction (3.4°±9.9° vs. 3.2°±5.5°; P=0.127), or cervical cobb angle correction (-5.7°±14.2° vs. -7.0°±12.2°; P=0.519). There were no significant long-term complications in either group. Conclusions: Skipping instrumentation at C7 in a multilevel posterior cervicothoracic fusion is associated with significantly reduced operative blood loss without loss of radiographic correction. This study demonstrates the clinical benefits of skipping C7 instrumentation in posterior cervicothoracic fusion with maintenance of radiographic correction parameters.

Generational Changes in Lumbar Spinal Canal Dimensions: Findings from a Sample U.S. Population.

OBJECTIVE: Evaluation of lumbar canal dimensions in a Chicago population born in 2 different decades. METHODS: This is a retrospective chart review analyzing computed tomography reconstruction from patients born between 1940 and 1949 (older group) and 1970 and 1979 (younger group). The cross-sectional area (CSA) and anterior-posterior diameter (APD) of the lumbar bony canal was measured at each lumbar level at the level of the pedicle. RESULTS: Our study includes 918 patients, 372 in the young group and 546 in the older group. Older patients have significantly larger CSA and APD at all lumbar levels compared with younger patients. Further, CSA and APD comparisons between ethnicities demonstrate significant differences between individuals of Caucasian, Asian, Hispanic, African American, and Other ethnicities. Lastly, there were no differences in CSA or APD compared with factors known to affect bone health (smoking, steroid use, osteoporosis, cancer history). CONCLUSIONS: As seen in European cohorts, our data suggest that patients born in the 1940s have both larger canal area and larger anterior-posterior diameter compared with the younger generation. These data suggest that significant differences exist between ethnicities. These differences highlight the importance of studying normal anatomical dimensions within different geographical populations and the importance of studying non-modifiable factors as they relate to spinal dimensions and spine patients. Furthermore, spinal canal growth seems to be negatively influenced in younger generations, a rather unexpected but worrying finding.

Safety and Efficacy of Skipping C7 Instrumentation in Posterior Cervicothoracic Fusion.

OBJECTIVE: To analyze the safety and efficacy of skipping instrumentation at the C7 vertebra during posterior cervicothoracic fusions. METHODS: This is a retrospective chart review of 53 patients who underwent multilevel posterior cervical fusion between 2010 and 2015. Of 53 patients, 7 patients were instrumented at C7, serving as the control group, whereas the remaining 46 patients were not. Evaluation of efficacy was based on intraoperative complications, operative time, estimated blood loss, significant long-term complications, and radiographic evidence of fusion. RESULTS: Skipping the C7 level resulted in a significant reduction in estimated blood loss (321 ± 214 mL in the C7 bridge group vs. 531 ± 365 mL in the control group) and an insignificant, but decreased, reduction in operative time (155 ± 70 minutes in the C7 bridge group vs. 194 ± 66 minutes in the control group). Two intraoperative complications were noted in the C7 group, and 1 intraoperative complication was noted in the control group. In addition, patients skipped at C7 maintained sagittal balance with fusion rates similar to control patients at follow-up. No significant long-term complications were found in both groups. CONCLUSIONS: Skipping C7 in a multilevel posterior cervicothoracic fusion demonstrates significantly reduced estimated blood loss and faster operative times compared with the control group. In addition, postoperative assessment yielded similar rates of fusion in both groups. Serious negative outcomes of skipping C7 were not found in this retrospective study. Our study results illustrate the clinical benefits of skipping instrumentation at C7 to minimize surgical risk in patients undergoing posterior cervical fusion across the cervicothoracic junction.

Axial and oblique C2 pedicle diameters and feasibility of C2 pedicle screw placement: Technical note.

BACKGROUND: For C2 pedicle screw placement/instrumentation, it is critical to adequately measure the axial and oblique C2 pedicle diameters utilizing the intraoperative O-arm. METHODS: Thirty-three patients who underwent C2 pedicle screw placement (2013-2016) utilizing the O-arm with tri-planar reconstruction. As O-arm software does not allow calibrated measurements with the application's measurement tool, we directly measured axial and oblique widths of the C2 pedicles on the screen with a regular ruler (e.g., "screen width of C2 pedicle"). RESULTS: The axial width of the C2 pedicles ranged from 6 to 15 mm on the right (mean 10.44 ± 2.15 mm) to 7 to 14 mm (10.29 ± 1.72 mm) on the left. The oblique width of C2 pedicles ranged from 10 to 19 mm on the right (mean, 14.73 ± 1.85 mm) and from 12 to 19 mm on the left (mean, of 15.33 ± 1.67 mm). These measurements indicated that oblique screen widths of the C2 pedicles were 1.4 and 1.5 times higher than their axial screen widths on the right and left sides, respectively. CONCLUSIONS: The oblique screen widths of the C2 pedicles better predict the feasibility of C2 pedicle screw placement vs. their axial screen width as measured with a regular ruler.

T-1 pedicle subtraction osteotomy for the treatment of rigid cervical kyphotic deformity: report of 4 cases.

Cervical kyphotic deformity represents a difficult to treat pathology often arising from multiple factors including, but not limited to, traumatic injuries, degenerative changes, and ankylosing spondylitis. Furthermore, treatment of these deformities becomes increasingly difficult with any preexisting instrumentation. Currently, several options exist to treat these severe deformities, with the Smith-Petersen osteotomy and C-7 pedicle subtraction osteotomy being the most frequently used approaches. However, these techniques come with significant risk to the patient including nerve root injury as well as compression of the vertebral arteries. The authors here report on a series of 4 patients with rigid cervical deformity who underwent T-1 pedicle subtraction osteotomy. The authors review the relevant literature and provide a novel, less risky, and potentially more corrective approach for treating cervical deformities.

Spinal epidural abscess in a patient with piriformis pyomyositis.

BACKGROUND: Spinal epidural abscess resulting from piriformis pyomyositis is extremely rare. Such condition can result in serious morbidity and mortality if not addressed in a timely manner. CASE DESCRIPTION: The authors describe the case of a 19-year-old male presenting with a 2-week history of fever, low back pain, and nuchal rigidity. When found to have radiographic evidence of a right piriformis pyomyositis, he was transferred to our institution for further evaluation. Because he demonstrated rapid deterioration, cervical, thoracic, and lumbar magnetic resonance imaging scans were emergently performed. They revealed an extensive posterior spinal epidural abscess causing symptomatic spinal cord compression extending from C2 to the sacrum. He underwent emergent decompression and abscess evacuation through a dorsal midline approach. Postoperatively, he markedly improved. Upon discharge, the patient regained 5/5 strength in both upper and lower extremities. Cultures from the epidural abscess grew methicillin-sensitive Staphylococcus aureus warranting a 6-week course of intravenous nafcillin. CONCLUSION: A 19-year-old male presented with a holospinal epidural abscess (C2 to sacrum) originating from piriformis pyomyositis. The multilevel cord abscess was emergently decompressed, leading to a marked restoration of neurological function.

Anterior cervical corpectomy and fusion for blastomycosis causing destruction of C6 vertebra: a case report.

INTRODUCTION: We describe a patient who had cervical spine osteomyelitis caused by Blastomyces dermatitidis that resulted in cord compression and cervical spine instability. CASE PRESENTATION: A 25-year-old Hispanic woman presented with fever, sweats, neck pain, and an enlarging neck mass with purulent discharge after sustaining a C6 vertebral body fracture. Magnetic resonance imaging confirmed C6 vertebral osteomyelitis, demonstrated by vertebral body destruction, cervical spine instability, prevertebral abscess, and spinal cord compression. She underwent C6 anterior cervical corpectomy and fusion, with fungal cultures confirming Blastomyces dermatitidis. CONCLUSIONS: Anterior cervical corpectomy and fusion successful debrided, decompressed, and restored cervical spine stability in a patient with vertebral osteomyelitis caused by Blastomyces dermatitidis. The patient was subsequently treated with a 1-year course of itraconazole and had no recurrence of infection 4 years postoperatively.

Comparison of perioperative complications following staged versus one-day anterior and posterior cervical decompression and fusion crossing the cervico-thoracic junction.

INTRODUCTION: Multilevel cervical pathology may be treated via combined anterior cervical decompression and fusion (ACDF) followed by posterior spinal instrumented fusion (PSIF) crossing the cervico-thoracic junction. The purpose of the study was to compare perioperative complication rates following staged versus same day ACDF combined with PSIF crossing the cervico-thoracic junction. MATERIAL AND METHODS: A retrospective review of consecutive patients undergoing ACDF followed by PSIF crossing the cervico-thoracic junction at a single institution was performed. Patients underwent either same day (group A) or staged with one week interval surgeries (group B). The minimum follow-up was 12 months. RESULTS: Thirty-five patients (14 females and 21 males) were analyzed. The average age was 60 years (37-82 years). There were 12 patients in group A and 23 in group B. Twenty-eight complications noted in 14 patients (40%) included: dysphagia in 13 (37%), dysphonia in 6 (17%), post-operative reintubation in 4 (11%), vocal cords paralysis, delirium, superficial incisional infection and cerebrospinal fluid leakage each in one case. Significant differences comparing group A vs. B were found in: the number of levels fused posteriorly (5 vs. 7; p=0.002), total amount of intravenous fluids (3233ml vs. 4683ml; p=0.03), length of hospital stay (10 vs. 18 days; p=0.03) and transfusion of blood products (0 vs. 9 patients). Smoking and cervical myelopathy were the most important risk factors for perioperative complications regardless of the group. CONCLUSIONS: Staging anterior cervical decompression and fusion with posterior cervical instrumented fusion 1 week apart does not decrease the incidence of perioperative complications.

All-posterior vertebral column resection for treatment of metastatic tumors.

This technical note describes a surgical technique for an all-posterior (ALL-P) vertebral column resection (VCR) in the treatment of metastatic tumors involving the thoracic spine in adults. A case report of an 18-year-old young man with metastatic T4 osteosarcoma is presented along with the surgical technique for ALL-P VCR, tips and tricks, potential complications, and postoperative management. Advantages and disadvantages of alternative operative methods as well as particular implant types used in ALL-P VCR are discussed.

Anterior approach for complex cervical spondylotic myelopathy.

Cervical spondylotic myelopathy (CSM) is a slowly progressive disease resulting from age-related degenerative changes in the spine that can lead to spinal cord dysfunction and significant functional disability. The degenerative changes and abnormal motion lead to vertebral body subluxation, osteophyte formation, ligamentum flavum hypertrophy, and spinal canal narrowing. Repetitive movement during normal cervical motion may result in microtrauma to the spinal cord. Disease extent and location dictate the choice of surgical approach. Anterior spinal decompression and instrumented fusion is successful in preventing CSM progression and has been shown to result in functional improvement in most patients.

Primitive neuroectodermal tumor after radiation therapy for craniopharyngioma.

The authors report a case of primitive neuroectodermal tumor induced by radiation therapy of craniopharyngioma. This African-American male patient originally presented with craniopharyngioma, for which he underwent resection and whole-brain radiation therapy. Eight years later, at the age of 20 years, he returned with a left facial droop and left hemiparesis. A right basal ganglia mass was identified and resected. Histopathological examination identified the lesion as primitive neuroectodermal tumor. Although radiation therapy has shown to be beneficial in decreasing the recurrence rate in subtotally resected craniopharyngioma, the risks of radiation treatment should be clearly communicated to the patients, their families, and neurosurgeons before starting such treatment. This report expands the spectrum of reported radiation-induced neoplasms in the CNS.

CT Ventriculography for diagnosis of occult ventricular cysticerci.

BACKGROUND: Neurocysticercosis is the most common parasitic infection of the central nervous system (CNS). Intraventricular lesions are seen in 7-20% of CNS cysticercosis. Intraventricular lesions can be missed by computed tomography (CT) and magnetic resonance imaging (MRI) as they are typically isodense/isointense to the cerebrospinal fluid. We present our experience with CT ventriculography to visualize occult cysts. CASE DESCRIPTION: Two patients presented with hydrocephalus and suspected neurocysticercosis were evaluated with CT and MRI with and without contrast failing to reveal intraventricular lesions. CT-ventriculography was used: 10 ml of cerebrospinal fluid was drained from the ventriculostomy catheter, and 10 ml of iohexol 240 diluted 1:1 with preservative-free saline was injected through the ventriculostomy catheter. Immediate CT of the brain was performed. The first patient had multiple cysts located throughout the body of the left lateral ventricle. The second patient had a single lesion located in the body of the lateral ventricle. The CT-ventriculography findings helped in identifying the lesions and plan the surgical intervention that was performed with the aid of an endoscope to remove the cysts. CONCLUSIONS: Intraventricular neurocysticercosis is a common parasitic disease which can be difficult to diagnose. We used CT-ventriculography with injection of contrast through the ventriculostomy catheter in two patients where CT and MRI failed to demonstrate the lesions. This technique is a safe and useful tool in the imaging armamentarium when intraventricular cystic lesions are suspected.

Ethylene oxide gas sterilization: a simple technique for storing explanted skull bone. Technical note.

The authors evaluated the effectiveness of a simple technique using ethylene oxide (EtO) gas sterilization and room temperature storage of autologous bone grafts for reconstructive cranioplasty following decompressive craniectomy. The authors retrospectively analyzed data in 103 consecutive patients who underwent cranioplasty following decompressive craniectomy for any cause at the University of Illinois at Chicago between 1999 and 2005. Patients with a pre-existing intracranial infection prior to craniectomy or lost to follow-up before reconstruction were excluded. Autologous bone grafts were cleansed of soft tissue, hermetically sealed in sterilization pouches for EtO gas sterilization, and stored at room temperature until reconstructive cranioplasty was performed. Cranioplasties were performed an average of 4 months after decompressive craniectomy, and the follow-up after reconstruction averaged 14 months. Excellent aesthetic and functional results after single-stage reconstruction were achieved in 95 patients (92.2%) as confirmed on computed tomography. An infection of the bone flap occurred in eight patients (7.8%), and the skull defects were eventually reconstructed using polymethylmethacrylate with satisfactory results. The mean preservation interval was 3.8 months in patients with uninfected flaps and 6.4 months in those with infected flaps (p = 0.02). A preservation time beyond 10 months was associated with a significantly increased risk of flap infection postcranioplasty (odds ratio [OR] 10.8, p = 0.02). Additionally, patients who had undergone multiple craniotomies demonstrated a trend toward increased infection rates (OR 3.0, p = 0.13). Data in this analysis support the effectiveness of this method, which can be performed at any institution that provides EtO gas sterilization services. The findings also suggest that bone flaps preserved beyond 10 months using this technique should be discarded or resterilized prior to reconstruction.

Virtual reality in neurosurgical education: part-task ventriculostomy simulation with dynamic visual and haptic feedback.

OBJECTIVE: Mastery of the neurosurgical skill set involves many hours of supervised intraoperative training. Convergence of political, economic, and social forces has limited neurosurgical resident operative exposure. There is need to develop realistic neurosurgical simulations that reproduce the operative experience, unrestricted by time and patient safety constraints. Computer-based, virtual reality platforms offer just such a possibility. The combination of virtual reality with dynamic, three-dimensional stereoscopic visualization, and haptic feedback technologies makes realistic procedural simulation possible. Most neurosurgical procedures can be conceptualized and segmented into critical task components, which can be simulated independently or in conjunction with other modules to recreate the experience of a complex neurosurgical procedure. METHODS: We use the ImmersiveTouch (ImmersiveTouch, Inc., Chicago, IL) virtual reality platform, developed at the University of Illinois at Chicago, to simulate the task of ventriculostomy catheter placement as a proof-of-concept. Computed tomographic data are used to create a virtual anatomic volume. RESULTS: Haptic feedback offers simulated resistance and relaxation with passage of a virtual three-dimensional ventriculostomy catheter through the brain parenchyma into the ventricle. A dynamic three-dimensional graphical interface renders changing visual perspective as the user's head moves. The simulation platform was found to have realistic visual, tactile, and handling characteristics, as assessed by neurosurgical faculty, residents, and medical students. CONCLUSION: We have developed a realistic, haptics-based virtual reality simulator for neurosurgical education. Our first module recreates a critical component of the ventriculostomy placement task. This approach to task simulation can be assembled in a modular manner to reproduce entire neurosurgical procedures.

Neuroenteric cyst of the anterior cranial fossa: case report and review of the literature.

A case of intradural neuroenteric cyst located in the anterior cranial fossa is presented. The cyst caused anosmia and progressive personality changes in an elderly woman. The patient underwent bifrontal craniotomy with evacuation of cyst contents and removal of the cyst wall. Incidence, classification, histopathology, and histogenesis of neuroenteric cysts are discussed with review of the literature.