James Kryzanski

C1-C2 arthrodesis after transoral odontoidectomy and suboccipital craniectomy for ventral brain stem compression in Chiari I patients.

Chiari I malformations are often associated with congenital craniocervical anomalies such as platybasia, basilar invagination, and retroflexion of the odontoid process. Management of ventral brain stem compression associated with Chiari I malformations remains controversial, but several authors report a significant rate of failure with suboccipital decompression alone in the presence of pronounced ventral brain stem compression (VBSC). Treatment options described in the literature for these patients involve anterior, posterior, or combined decompressions with or without concurrent arthrodesis. A combined anterior and posterior approach provides a definitive circumferential decompression but also significantly disrupts the stability of the occipitocervical junction usually necessitating occipitocervical fixation. We describe an alternative surgical treatment for Chiari I patients with significant ventral brain stem compression where a combined anterior and posterior decompression was considered necessary. We report two patients who underwent transoral odontoidectomy with preservation of the anterior arch of the atlas and suboccipital craniectomy with C1 laminectomy followed by C1–C2 arthrodesis. Preservation of the anterior arch of the atlas in conjunction with C1–C2 arthrodesis stabilizes the occipito–atlanto-axial segments while conserving more cervical mobility as compared to an occipitocervical fusion.

Low Complication Rates of Cranial and Craniofacial Approaches to Midline Anterior Skull Base Lesions

OBJECTIVE Surgery is a cornerstone of treatment for a wide variety of neoplastic, congenital, traumatic, and inflammatory lesions involving the midline anterior skull base and may result in a significant anterior skull base defect requiring reconstruction. This study is a retrospective analysis of the reconstruction techniques and complications seen in a series of 58 consecutive patients with midline anterior skull base pathology treated with craniotomy or a craniofacial approach. The complication rates in this series are compared with other retrospective series and specific techniques that may reduce complications are then discussed. DESIGN This is a retrospective analysis of 58 consecutive patients who had surgery for a midline anterior skull base lesion between January 1994 and July 2003. Data were collected regarding pathology, surgical approach, reconstruction technique, and complications. RESULTS Twenty-nine patients underwent surgery for a meningioma (50%). The remainder had frontoethmoidal cancer, mucoceles/invasive nasal polyps, encephalocele, esthesioneuroblastoma, anterior falx dermoid cyst with a nasal sinus tract, or invasive pituitary adenoma. In most patients, a low and narrow two-piece biorbitofrontal craniotomy was used. When possible, the dura was repaired before entering the nasal cavity. Thirteen patients experienced a complication (22%). There was one case of postoperative cerebrospinal fluid (CSF) leak (2%), one case of meningitis (2%), two cases of bone flap infection (3%), and two cases of symptomatic pneumocephalus (3%). There were no deaths, no reoperations for CSF leak, and no patient had a new permanent neurologic deficit other than anosmia. CONCLUSIONS Transcranial approaches for midline anterior skull base lesions can be performed safely with a low incidence of postoperative CSF leak, meningitis, bone flap infection, and symptomatic pneumocephalus. Our results, particularly with regard to CSF leakage, compare favorably with other retrospective series.

A review of the combined medical and surgical management in patients with herpes simplex encephalitis

BACKGROUND Herpes simplex encephalitis (HSE) is a devastating and severe viral infection of the human central nervous system. This viral encephalitis is well known to cause severe cerebral edema and hemorrhagic necrosis with resultant increases in intracranial pressure (ICP). While medical management has been standardized in the treatment of this disease, the role of aggressive combined medical and surgical management including decompressive craniectomy and/or temporal lobectomy has not been fully evaluated. In addition, while barbiturate coma has been studied for treatment of status epilepticus associated with infectious encephalitis, its use for treatment of encephalitis associated intractable intracranial hypertension has not been fully reported. CASE DESCRIPTION We report the case of a 22 year old female with severe herpetic encephalitis requiring aggressive ICP management utilizing all modalities (both medical and surgical) known to control ICP. She continues to have memory deficits but has made a good recovery with a Glasgow Outcome Scale score of 5. CONCLUSION We provide evidence that aggressive combined medical and surgical therapy is warranted even in cases of severe HSE with transtentorial herniation, as there is evidence for the potential of good recovery. A detailed literature review of the medical and surgical management strategies in this disease is presented.

Utility of STIR MRI in pediatric cervical spine clearance after trauma.

OBJECT Although MRI with short-term T1 inversion recovery (STIR) sequencing has been widely adopted in the clearance of cervical spine in adults who have sustained trauma, its applicability for cervical spine clearance in pediatric trauma patients remains unclear. The authors sought to review a Level 1 trauma centers experience using MRI for posttraumatic evaluation of the cervical spine in pediatric patients. METHODS A pediatric trauma database was retrospectively queried for patients who received an injury warranting radiographic imaging of the cervical spine and had a STIR-MRI sequence of the cervical spine performed within 48 hours of injury between 2002 and 2011. Demographic, radiographic, and outcome data were retrospectively collected through medical records. RESULTS Seventy-three cases were included in the analysis. The mean duration of follow-up was 10 months (range 4 days-7 years). The mean age of the patients at the time of trauma evaluation was 8.3 ± 5.8 years, and 65% were male. The majority of patients were involved in a motor vehicle accident. In 70 cases, the results of MRI studies were negative, and the patients were cleared prior to discharge with no clinical suggestion of instability on follow-up. In 3 cases, the MRI studies had abnormal findings; 2 of these 3 patients were cleared with dynamic radiographs during the same admission. Only 1 patient had an unstable injury and required surgical stabilization. The sensitivity of STIR MRI to detect cervical instability was 100% with a specificity of 97%. The positive predictive value was 33% and the negative predictive value was 100%. CONCLUSIONS Although interpretation of our results are diminished by limitations of the study, in our series, STIR MRI in routine screening for pediatric cervical trauma had a high sensitivity and slightly lower specificity, but may have utility in future practices and should be considered for implementation into protocols.

Spontaneous resolution of an acute epidural hematoma with normal intracranial pressure: case report and literature review

Traumatic epidural hematomas are critical emergencies in neurosurgery, and patients symptomatic from acute epidural hematomas are typically treated with rapid surgical decompression. However, some patients, if asymptomatic, may be treated with close clinical observation and serial imaging. Although rare, rapid spontaneous resolution of epidural hematomas in the pediatric population has even been reported, with only seven cases in the literature. Numerous theories have been proposed to explain the pathophysiology behind these cases, including egress of epidural collections through cranial discontinuities (fractures/open sutures), blood that originates in the subgaleal space, and bleeding from the cranial diploic cavity after a skull fracture that preferentially expands into the subgaleal space. We report the case of a rapidly resolving epidural hematoma in a 13-year-old boy. This case allows for more detailed inferences to be made concerning the nature of the epidural hematoma’s resolution, as it is the first reported case in which an intracranial pressure monitor has been utilized. We also review the literature and discuss the nature of rapid spontaneous epidural hematoma resolution.

Nerve root anomalies: implications for transforaminal lumbar interbody fusion surgery and a review of the Neidre and Macnab classification system

Lumbar nerve root anomalies are uncommon phenomena that must be recognized to avoid neural injury during surgery. The authors describe 2 cases of nerve root anomalies encountered during mini-open transforaminal lumbar interbody fusion (TLIF) surgery. One anomaly was a confluent variant not previously classified; the authors suggest that this variant be reflected in an amendment to the Neidre and Macnab classification system. They also propose strategies for identifying these anomalies and avoiding injury to anomalous nerve roots during TLIF surgery. Case 1 involved a 68-year-old woman with a 2-year history of neurogenic claudication. An MR image demonstrated L4-5 stenosis and spondylolisthesis and an L-4 nerve root that appeared unusually low in the neural foramen. During a mini-open TLIF procedure, a nerve root anomaly was seen. Six months after surgery this patient was free of neurogenic claudication. Case 2 involved a 60-year-old woman with a 1-year history of left L-4 radicular pain. Both MR and CT images demonstrated severe left L-4 foraminal stenosis and focal scoliosis. Before surgery, a nerve root anomaly was not detected, but during a unilateral mini-open TLIF procedure, a confluent nerve root was identified. Two years after surgery, this patient was free of radicular pain.

A Minimal Access Far-Lateral Approach to Foramen Magnum Lesions

Objectives The far-lateral approach is widely used to treat pathology of the ventral foramen magnum. Numerous methods of exposure have been described, most of which utilize long skin incisions and myocutaneous flaps. Here we present our experience with gaining exposure through a small paramedian incision using a muscle-splitting technique. Design A cadaveric anatomical study was first performed to verify the feasibility of the approach. We then describe our experience with using the approach in 13 patients. A retrospective chart review was performed and data regarding pathology, imaging, and complications were collected. Results The cadaveric study confirmed that a small paramedian muscle-splitting approach allows sufficient exposure to approach many foramen magnum lesions. Our case series included 10 patients with meningioma, one brainstem glioblastoma, one posterior inferior cerebellar artery aneurysm, and one odontoid pannus. The exposure was adequate in all cases. For the meningioma patients, six had gross total resections and four had subtotal resection because of tumor adherence to neurovascular structures. Two patients experienced postoperative cardiovascular complications. There were no new neurologic deficits, cerebrospinal fluid leaks, or wound complications. Conclusions A small paramedian incision may be used to gain exposure and perform successful far-lateral approaches. The small exposure is likely to reduce the risk of local complications such as cerebrospinal fluid fistula and pseudomeningocele when compared with larger exposures.

Lateral retroperitoneal transpsoas approach to the lumbar spine for the treatment of spondylodiscitis.

Abstract Spondylodiscitis is an infection of the intervertebral disc and adjacent vertebrae. With the advent of minimally invasive spinal surgery, less invasive approaches have been considered for the treatment of discitis. To date, however, there have been no reported cases of a minimally invasive lateral retroperitoneal transpsoas approach for the treatment of spondylodiscitis. The authors report a case of medically refractory discitis in a patient with multiple comorbidities who underwent a successful limited debridement via a lateral transpsoas corridor. This case describes a minimally invasive approach used to treat a patient with lumbar discitis/osteomyelitis who was otherwise a suboptimal surgical candidate.

Unilateral Pedicle Screw Fixation is Associated with Reduced Cost and Similar Outcomes in Selected Patients Undergoing Minimally Invasive Transforaminal Lumbar Interbody Fusion for L4-5 Degenerative Spondylolisthesis.

Study design: Retrospective study of 24 patients who underwent either a bilateral or unilateral TLIF procedure for the treatment of degenerative spondylolisthesis. Objective: To analyze differences in cost and outcome between patients undergoing minimally invasive transforaminal lumbar interbody fusion (mi-TLIF) with unilateral or bilateral pedicle screw fixation for L4-5 degenerative spondylolisthesis. Summary of background data: Lumbar fusion surgeries, including the TLIF procedure, have been shown to be an effective treatment for leg and low back pain caused by degenerative spondylolisthesis. Some studies have shown TLIF surgeries to be cost-effective, but there is still a paucity of data and no consensus. Unilateral TLIFs can provide the same benefits as bilateral TLIFs, but come with additional benefits of a less invasive surgery. Methods: We retrospectively analyzed a consecutive series of patients with L4-5 degenerative stenosis and spondylolisthesis who either received a unilateral or bilateral mi-TLIF, paying particular attention to hospital cost and clinical outcome. Of the 33 patients eligible for analysis, we were able to obtain appropriate clinical and radiographic follow-up data on 24 patients (72.7%), 14 patients who underwent unilateral fixation, and 10 patients who underwent bilateral fixation. Results: The cohorts were similar with regard to age, comorbidities, and demographics. Most patients reported good or excellent results, and there were no significant differences between the cohorts with regard to clinical outcome. There was one interbody graft extrusion in the unilateral cohort that required explantation, but no other hardware failures. Hospital cost was significantly lower in the unilateral cohort, and hardware savings accounted for only part of the difference. Conclusion: Unilateral pedicle screw fixation is an acceptable surgical strategy in patients with stable L4-5 degenerative spondylolisthesis undergoing mi-TLIF. In our series, unilateral fixation led to significant hospital cost savings without compromising clinical or radiographic outcomes.

Pigmented villonodular synovitis of the thoracic spine

Pigmented villonodular synovitis (PVNS) is a proliferative lesion of the synovial membranes. Knees, hips, and other large weight-bearing joints are most commonly affected. PVNS rarely presents in the spine, in particular the thoracic segments. We present a patient with PVNS in the thoracic spine and describe its clinical presentation, radiographic findings, pathologic features, and treatment as well as providing the first comprehensive meta-analysis and review of the literature on this topic, to our knowledge. A total of 28 publications reporting 56 patients were found. The lumbar and cervical spine were most frequently involved (40% and 36% of patients, respectively) with infrequent involvement of the thoracic spine (24% of patients). PVNS affects a wide range of ages, but has a particular predilection for the thoracic spine in younger patients. The mean age in the thoracic group was 22.8 years and was significantly lower than the cervical and lumbar groups (42.4 and 48.6 years, respectively; p=0.0001). PVNS should be included in the differential diagnosis of osteodestructive lesions of the spine, especially because of its potential for local recurrence. The goal of treatment should be complete surgical excision. Although the pathogenesis is not clear, mechanical strain may play an important role, especially in cervical and lumbar PVNS. The association of thoracic lesions and younger age suggests that other factors, such as neoplasia, derangement of lipid metabolism, perturbations of humoral and cellular immunity, and other undefined patient factors, play a role in the development of thoracic PVNS.