Todd W. Vitaz

Adverse Effects Associated With High-dose Recombinant Human Bone Morphogenetic Protein-2 Use in Anterior Cervical Spine Fusion

Study Design. A retrospective review of patients who underwent an anterior cervical fusion using recombinant human bone morphogenetic protein (rhBMP)-2 with an absorbable collagen sponge (INFUSE®; Medtronic Sofamor Danek, Minneapolis, MN). Objective. To ascertain the complication rate after the use of high-dose INFUSE® in anterior cervical fusions. Summary of Background Data. The rhBMP-2 has been primarily investigated in lumbar spine fusions, where it has significantly enhanced the fusion rate and decreased the length of surgery, blood loss, and hospital stay. Methods. We present 151 patients who underwent either an anterior cervical discectomy and fusion (n = 138) or anterior cervical vertebrectomy and fusion (n = 13) augmented with high-dose INFUSE® between July 2003 and March 2004. The rhBMP-2 (up to 2.1 mg/level) was used in the anterior cervical discectomy and fusions. Results. A total of 35 (23.2%) patients had complications after the use of high-dose INFUSE® in the cervical spine. There were 15 patients diagnosed with a hematoma, including 11 on postoperative day 4 or 5, of whom 8 were surgically evacuated. Thirteen individuals had either a prolonged hospital stay (>48 hours) or hospital readmission because of swallowing/breathing difficulties or dramatic swelling without hematoma. Conclusions. A significant rate of complications resulted after the use of a high dose of INFUSE® in anterior cervical fusions. We hypothesize that in the cervical area, the putative inflammatory effect that contributes to the effectiveness of INFUSE® in inducing fusion may spread to adjacent critical structures and lead to increased postoperative morbidity. A thorough investigation is warranted to determine the optimal dose of rhBMP-2 that will promote cervical fusion and minimize complications.

Outcome following moderate traumatic brain injury

BACKGROUND Little is known about the outcome following moderate traumatic brain injury (TBI) (GCS 9-12). Most patients regain consciousness; however, the full magnitude of long-term cognitive and functional deficits is unknown. METHODS We conducted a prospective observational study evaluating the outcome of patients suffering moderate TBI between October 1995 and March 1998. Long-term outcome was assessed by telephone interviews. RESULTS A total of 79 consecutive patients were included. Average length of ICU and total hospital stay was 9.1 and 15.8 days respectively. The median GCS at 24 hours was 10 with 67% improving to GCS 15 by time of discharge. The presence of multisystem trauma did not affect outcome; however, age >/=45, initiation of enteral feeding after postinjury day 4 and the presence of pneumonia were all associated with longer lengths of stay and increased complication rates. Fifty-six (71%) patients were contacted for follow-up at an average of 27.5 months. GOS scores were 5 in 44%, 4 in 41%, 3 in 9%, 1 in 6%. Seventy-four percent of patients employed premorbidly returned to full-time work. Questions regarding cognitive and functional status revealed significant problems in the majority of patients. CONCLUSIONS Pneumonia, age >/=45 years and a delay in initiation of enteral feeding all increased the duration of acute care hospital stay following moderate TBI. In addition, cognitive, emotional, and functional problems following such injuries are extensive and long lasting. Physicians must be knowledgeable of these long-term sequela so they can provide the appropriate support and treatment to these patients.

Development and implementation of a clinical pathway for severe traumatic brain injury.

BACKGROUND Clinical pathways (CPs) have been shown to be beneficial in optimizing patient care and resource use. METHODS A multidisciplinary CP for the treatment of severe traumatic brain injury (Glasgow Coma Scale score of 3-7) was developed. Data from these patients (group I) were collected prospectively and compared with a retrospective database (group II). RESULTS There were a total of 119 patients managed in conjunction with the CP and 43 patients in the control group. No statistical differences were found between the groups in age, Glasgow Coma Scale score at 24 hours, or Injury Severity Scores. There was a significant decrease in the length of hospital stay, intensive care unit stay, and length of ventilator support in the study group (group I: 22.5, 16.8, and 11.5 days, respectively; group II: 31.0, 21.2, and 14.4 days, respectively; p < 0.03). CONCLUSION The use of this CP helped to standardize and improve patient care with fewer complications and a potential cost savings of approximately

Dynamic weight-bearing cervical magnetic resonance imaging: technical review and preliminary results.

14,000 per patient.

Successful incorporation of the Severe Head Injury Guidelines into a phased-outcome clinical pathway.

Background: Conventional magnetic resonance imaging (MRI) of complex cervical spine disorders may underestimate the magnitude of structural disease because imaging is performed in a nondynamic non-weight-bearing manner. Myelography provides additional information but requires an invasive procedure. Methods: This was a prospective review of the first 20 upright weight-bearing cervical MRI procedures with patients in the flexed, neutral, and extended positions conducted in an open-configuration MRI unit. Results: This technique clearly illustrated the changes in spinal cord compression, angulation, and spinal column alignment that occur during physiologic movements with corresponding changes in mid-sagittal spinal canal diameter (P < 0.05). Image quality was excellent or good in 90% of the cases. Conclusions: Dynamic weight-bearing MRI provides an innovative method for imaging complex cervical spine disorders. This technique is noninvasive and has adequate image quality that may make it a good alternative to cervical myelography.

Intraoperative MRI for transphenoidal procedures: Short-term outcome for 100 consecutive cases

&NA; Clinical pathways have been proven to be valu able tools in improving outcomes in patients with neuro logical diagnoses. However, their use with trauma populations has been limited. The unpredictable nature of trauma makes it difficult to develop a day‐by‐day plan of care that would be applicable to all patients with the same trauma diagnosis. Nev ertheless, a severe traumatic brain injury (TBI) clinical pathway was developed and implemented at a Level 1 Trauma Center with significant reductions in length of stay and number of ven tilator days. With the publication of the Guidelines for the Management of Severe Head Injury, this pathway was refashioned into a severe TBI phased‐outcome pathway. Rather than a day‐by‐day plan of care, this clinical pathway consists of four phases of care: (a) admission to the intensive care unit, (b) acute critical care, (c) mobility and weaning, and (d) pre‐reha bilitation. After 12 months, the improvements accomplished by the original pathway have been maintained or exceeded.

Changes in Cyst Volume following Intraoperative MRI-Guided Ommaya Reservoir Placement for Cystic Craniopharyngioma

BACKGROUND The majority of pituitary lesions are benign and can be cured with complete surgical resection. However, the transsphenoidal technique (the most common approach for pathology in this region) is limited by poor visualization and anatomical constraints. This can lead to incomplete tumor resection and thus increased recurrence rates. The use of iMRI during these procedures offers the advantage of radiographic confirmation during the procedure and may improve extent of resection. We reviewed our experience with this technology in 100 consecutive cases and compared the outcomes to published results. METHODS 100 patients were treated via transnasal transsphenoidal approach using the GE Signa SP 0.5Tesla (double doughnut design) iMRI system between July 2002 and August 2009 and followed prospectively. Intraoperative findings, imaging results, postoperative MRI and clinical outcome were evaluated to determine the extent of tumor resection, monitor for recurrence and determine outcome. RESULTS There were 100 patients studied, 81 macroadenomas, 9 microadenomas, and 10 other pathological diagnosis. The average extent of resection was 96% with gross total resection based on iMRI in 76 patients (76%). Four patients (4%) all with macroadenomas greater than 4 cm experienced major perioperative complications (hydrocephalus 2, thalamic infarct 1, major arterial bleeding 1), six patients (6%) developed post-operative CSF leaks, one patient (1%) had post-operative worsening of visual fields, and five patients (5%) had abdominal fat graft infections. Nine patients (9%) including five with known residual tumor required post-operative adjuvant treatment during the follow-up period secondary to either disease progression or failure to achieve endocrinological cure. CONCLUSIONS iMRI-guided transsphenoidal pituitary surgery provides the surgeon with immediate radiographic feedback during the procedure and aides in overcoming the limitations in direct visualization during such procedures. As a result of this it may enable surgeons to perform such procedures with fewer complications and increased rate of gross total resection. However, the impact of this technology on long-term tumor control still needs to be determined with further follow-up.

Intraoperative MRI for Pediatric Tumor Management

Introduction: Intracavitary treatment of solitary cystic craniopharyngiomas with 32P is an emerging treatment option, especially for pediatric patients. We have treated two patients with solitary cystic craniopharyngiomas using intraoperative MRI (iMRI)-guided catheter placement. Methods: The optical tracking system of the General Electric Signa SP iMRI system was utilized for preoperative planning and intraoperative catheter tracking during insertion. Intraoperative volumetric imaging was then used to confirm final catheter position. Patients were brought back to the iMRI suite approximately 8 weeks later and diluted gadolinium was injected with further MRI to confirm the absence of communication between the cyst lumen and surrounding CSF spaces and for volumetric analysis. Results: Intraoperative imaging illustrated deformation and changes in the cyst wall during catheter placement and cyst aspiration and confirmed final catheter placement. Images acquired 8 weeks following catheter placement prior to the instillation of 32P showed decreases in cyst volume of 40 and 85%. Conclusion: iMRI-guided catheter placement for cystic craniopharyngiomas helps to assure successful catheter placement. Significant decreases in cyst volume occur in the interval between catheter placement and 32P administration and must be accounted for to prevent overdosing of the radioisotope.

Interventional MRI-Guided Frameless Stereotaxy in Pediatric Patients

The emergence of intraoperative MRI has opened new doors for the surgical treatment of pediatric disorders. This technology will hopefully not only improve the surgeons ability to obtain complete tumor resections with minimal damage to surrounding structures, but also allows surgeons to perform various procedures via less invasive measures. We performed a total of 38 procedures in 36 children in our intraoperative MRI system (GE Signa SP, open configuration). All procedures were performed within the magnet bore, which allows for either continuous real-time or periodic imaging. Procedures included craniotomy for tumor resection, open biopsy, stereotactic biopsy or catheter placement into a tumor-related cyst. There were no infectious, hemorrhagic or neurological complications. Intraoperative MRI is an useful tool for the management of pediatric neurosurgical disorders. Intraoperative imaging not only helps surgeons navigate through eloquent areas of the brain, but also ensures the maximal possible tumor resection or confirms adequate catheter placement prior to skin closure. The impact of this technology on long term survival is yet to be determined.

Development and implementation of a clinical pathway for spinal cord injuries.

Introduction: We prospectively reviewed our experience with intraoperative MRI (iMRI)-guided stereotactic procedures in pediatric patients. Methods: All procedures were performed within the magnet bore of the General Electric Signa SP MRI system, which allows for either continuous real-time or periodic imaging. The internal optical tracking system was used to plan and monitor target localization and instrument trajectory. Results: Fifteen patients underwent 16 frameless stereotactic procedures, consisting of 4 tumor biopsies and 12 cyst aspirations and stereotactic catheter placements (average age 6 years, range 6 weeks to 18 years). There were no hemorrhagic, neurologic or infectious complications. Conclusion: iMRI is an important component in expanding the horizon of minimally invasive neurosurgery for pediatric patients. Thus far, we have found this technology to be safe, reliable and extremely useful for frameless stereotactic procedures.