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Michael P. Steinmetz, Ann Warbel, Melvin Whitfield and William Bingaman

Object. Despite the wide use of anterior cervical instrumentation in the management of multilevel cervical spondylosis, the incidences of pseudarthrosis and instrument-related failure remain high. The use of a dynamic implant may aid in the prevention of these complications. The purpose of this study was to evaluate the DOC dynamic cervical implant in the treatment of multilevel cervical spondylosis.

Methods. The authors evaluated 34 cases in which anterior multilevel cervical decompression and fusion were performed using the DOC Ventral Cervical Stabilization System. Postoperatively, and at each follow-up visit, the sagittal angle and the degree of subsidence that developed were measured. Fusion rates and clinical outcomes were also evaluated.

The mean postoperative sagittal angle was 14° of lordosis. The mean change in the sagittal angle during the follow-up period was 0.4° of lordosis. By 6 months postoperatively some subsidence had occurred in most patients, with no subsidence occurring in only 15%. By 3 months greater than or equal to 2 mm of subsidence was demonstrated in 61% of cases. The overall fusion rate was 91%. In the majority of patients (79%) symptoms were judged to be improved or resolved.

Conclusions. The DOC dynamic cervical implant permitted controlled subsidence and prevented progression of kyphotic deformity. There was one construct failure (related to a motor vehicle accident) and an overall fusion rate of 91%. The DOC implant is a safe and effective cervical construct for multilevel spondylotic disease.

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Wayel Kaakaji, Gene H. Barnett, Diane Bernhard, Ann Warbel, Karen Valaitis and Sarah Stamp

Object. The goal of this study was to determine the clinical and economic consequences of early discharge (< 8 hours) of patients following stereotactic brain biopsy (SBB).

Methods. The records of all patients who underwent percutaneous SBB at The Cleveland Clinic Foundation, a tertiary care teaching hospital, during 1994 and 1995 (Group A) were retrospectively reviewed to collect data on the nature and timing of perioperative (< 48 hours) clinical and radiological complications. Biopsies were performed using image-guided stereotaxy either with or without a frame. Based on the results, guidelines for early discharge of patients following SBB were implemented. Information on the nature and timing of perioperative complications was also collected prospectively in all patients who underwent percutaneous SBB from January 1996 through July 1998 (Group B). Hospital financial records for patients who underwent SBB in 1997 and 1998 were also reviewed and assessed for net revenue stratified by discharge status: early discharge (< 8 hours), extended outpatient observation (≥ 8 and < 24 hours), and inpatient hospitalization (≥ 24 hours).

In Group A, 130 biopsies were performed. There were five serious complications (3.8%), of which four were transient, and there was one death (0.8%). The death and any sustained deficit occurred in patients in whom a clot had been demonstrated on postoperative CT scans. All complications were detected within 6 hours after surgery. Intraoperative bleeding occurred in 12 patients (9.2%), but was associated with only 40% of cases in which hemorrhage appeared on postoperative CT scans. Guidelines for early discharge (< 8 hours) following SBB were developed and stipulated the absence of the following: 1) intraoperative hemorrhage; 2) new postoperative deficit; and 3) clot on a postoperative CT scan.

In Group B, 139 biopsies were performed. There were three serious complications (2.2%), one of which was sustained due to a clot that had been demonstrated on the postoperative CT scan. All complications were detected within 6 hours postsurgery. There were no deaths in this group. Intraoperative bleeding occurred in 11 patients (7.9%), requiring intraoperative craniotomy to control bleeding in one case.

Hospital financial records were available for 96 patients, of whom 22 were discharged from the hospital early, 11 were observed for an extended outpatient period, and the remainder were retained for inpatient hospitalization. Average net hospital incomes on technical charges for patients in the inpatient hospitalization, extended outpatient observation, and short-stay (early discharge) groups were $1778, $1175, and $1219, respectively, in 1997, but declined to −$889, −$1339, and $671, respectively, in 1998. The ratios of indirect costs to direct technical costs were 132.5%, 128.7%, and 103.7%, respectively.

Conclusions. Early discharge of patients following SBB of supratentorial lesions is safe in the absence of excessive intraoperative bleeding, new postoperative deficit, and clot on a postoperative CT scan. Extended outpatient observation (8–23 hours) is not clinically necessary and may be economically prohibitive in the setting of a teaching hospital.

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Nitin Tandon, Andreas V. Alexopoulos, Ann Warbel, Imad M. Najm and William E. Bingaman


Occipital resections for epilepsy are rare. Reasons for this are the relative infrequency of occipital epilepsy, difficulty in localizing epilepsy originating in the occipital lobe, imprecisely defined seizure outcome in patients treated with focal occipital resections in the MR imaging era, and concerns about producing visual deficits. The impact of lesion location on vision and seizure biology, the management decision-making process, and the outcomes following resection need elaboration.


The authors studied 21 consecutive patients who underwent focal occipital resections for epilepsy at Cleveland Clinic Epilepsy Center over a 13-year period during which MR imaging was used. Demographics, imaging, and data relating to the epilepsy and its surgical management were collected. The collateral sulcus, the border between the medial surface and the lateral convexity, and the inferior temporal sulcus were used to subdivide the occipital lobe into medial, lateral, and basal zones. Lesions that did not involve most or all of the occipital lobe (sublobar) were spatially categorized into these zones. Visual function, semiology, and scalp electroencephalography were evaluated in relation to these spatial categories. Preresection and postresection visual function and seizure frequency were evaluated and compared. Lastly, an exhaustive review and discussion of the published literature on occipital resections for epilepsy was carried out.


Five lesions were lobar and 16 were sublobar. Patients with medial or lobar lesions had a much greater likelihood of preoperative visual field defects. Those with basal or lateral lesions had a greater likelihood of having a visual aura preceding some or all of their seizures and a trend (not significant) toward having a concordant lateralized onset by scalp electroencephalography. Invasive recordings were used in 8 cases. All patients had lesions (malformations of cortical development, tumors, or gliosis) that were completely resected, as evaluated on postoperative MR imaging. At last follow-up, 17 patients (81%) were seizure free or had only occasional auras (Wieser Class 1 or 2). The remaining 4 patients (19%) had a worthwhile improvement in seizure control (Class 3 or 4). Of the patients for whom both pre- and postoperative visual testing data were available, 50% suffered no new visual deficits, and 17% each developed a new quadrantanopia or a hemianopia.


Lesional occipital lobe epilepsy can be successfully managed with resection to obtain excellent seizure-free rates. Individually tailored resections (in lateral occipital lesions, for example) may help preserve intact vision in a subset of cases (38% in this series). Invasive recordings may further guide surgical decision-making as delineated by an algorithm generated by the authors. The authors' results suggest that the spatial location of the lesion correlates both with the semiology of the seizure and with the presence of visual deficit.

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Michael P. Steinmetz, Jared Miller, Ann Warbel, Ajit A. Krishnaney, William Bingaman and Edward C. Benzel


The cervicothoracic junction (CTJ) is the transitional region between the cervical and thoracic sections of the spinal axis. Because it is a transitional zone between the mobile lordotic cervical and rigid kyphotic thoracic spines, the CTJ is a region of potential instability. This potential for instability may be exaggerated by surgical intervention.


A retrospective review of all patients who underwent surgery involving the CTJ in the Department of Neurosurgery at the Cleveland Clinic Foundation during a 5-year period was performed. The CTJ was strictly defined as encompassing the C-7 vertebra and C7–T1 disc interspace. Patients were examined after surgery to determine if treatment had failed. Failure was defined as construct failure, deformity (progression or de novo), or instability. Variables possibly associated with treatment failure were analyzed. Statistical comparisons were performed using the Fisher exact test.

Between January 1998 and November 2003, 593 CTJ operations were performed. Treatment failed in 14 patients. Of all variables studied, failure was statistically associated with laminectomy and multilevel ventral corpectomies with fusion across the CTJ. Other factors statistically associated with treatment failure included histories of cervical surgery, tobacco use, and surgery for the correction of deformity.


The CTJ is a vulnerable region, and this vulnerability is exacerbated by surgery. Results of the present study indicate that laminectomy across the CTJ should be supplemented with instrumentation (and fusion). Multilevel ventral corpectomies across the CTJ should also be supplemented with dorsal instrumentation. Supplemental instrumentation should be considered for patients who have undergone prior cervical surgery, have a history of tobacco use, or are undergoing surgery for deformity correction.

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010