Christopher I. Shaffrey
Y. Raja Rampersaud
Melvin Field, Timothy F. Witham, John C. Flickinger, Douglas Kondziolka and L. Dade Lunsford
Object. Stereotactic brain biopsy has played an integral role in the diagnosis and management of brain lesions. At most centers, imaging studies following biopsy are rarely performed. The authors prospectively determined the acute hemorrhage rate after stereotactic biopsy by performing immediate postbiopsy intraoperative computerized tomography (CT) scanning. They then analyzed factors that may influence the risk of hemorrhage and the diagnostic accuracy rate.
Methods. Five hundred consecutive patients undergoing stereotactic brain biopsy underwent immediate postbiopsy intraoperative CT scanning. Before surgery, routine preoperative coagulation studies were performed in all patients. All medical charts, laboratory results, preoperative imaging studies, and postoperative imaging studies were reviewed.
In 40 patients (8%) hemorrhage was detected using immediate postbiopsy intraoperative CT scanning. Neurological deficits developed in six patients (1.2%) and one patient (0.2%) died. Symptomatic delayed neurological deficits developed in two patients (0.4%), despite the fact that the initial postbiopsy CT scans in these cases did not show acute hemorrhage. Both patients had large intracerebral hemorrhages that were confirmed at the time of repeated imaging. The results of a multivariate logistic regression analysis of the risk of postbiopsy hemorrhage of any size showed a significant correlation only with the degree to which the platelet count was below 150,000/mm3 (p = 0.006). The results of a multivariate analysis of a hemorrhage measuring greater than 5 mm in diameter also showed a correlation between the risk of hemorrhage and a lesion location in the pineal region (p = 0.0086). The rate at which a nondiagnostic biopsy specimen was obtained increased as the number of biopsy samples increased (p = 0.0073) and in accordance with younger patient age (p = 0.026).
Conclusions. Stereotactic brain biopsy was associated with a low likelihood of postbiopsy hemorrhage. The risk of hemorrhage increased steadily as the platelet count fell below 150,000/mm3. The authors found a small but definable risk of delayed hemorrhage, despite unremarkable findings on an immediate postbiopsy head CT scan. This risk justifies an overnight hospital observation stay for all patients after having undergone stereotactic brain biopsy.
Carlos A. Bagley, Markus J. Bookland, Jonathan A. Pindrik, Tolga Ozmen, Ziya L. Gokaslan and Timothy F. Witham
Spinal column metastatic disease clinically affects thousands of cancer patients every year. Local chemotherapy represents a new option in the treatment of metastatic disease of the spine. Despite the clinical impact of metastatic spine disease, the literature currently lacks an accurate animal model for the effective dosing of local chemotherapeutic agents within the vertebral column.
Female Fischer 344 rats, weighing 150 to 200 g each, were used in this study. After induction of anesthesia, a transabdominal approach to the ventral vertebral body of L-6 was performed. A small hole was drilled and 5 μL of ReGel (blank polymer), OncoGel (paclitaxel and ReGel) 1.5%, OncoGel 3.0%, or OncoGel 6.0% were immediately injected to determine drug toxicity. Based on these results, efficacy studies were performed by intratumoral injection of 5 μL of ReGel, OncoGel 3.0%, and OncoGel 6.0% on Day 6 in a CRL-1666 breast adenocarcinoma metastatic spine tumor model. Hind limb function was tested pre- and postoperatively using the Basso-Beattie-Bresnahan rating scale. Histological analysis of the spinal cord and vertebral column was performed when the animal died or was killed.
There were no signs of toxicity observed in association with any of the agents under study. No increased benefit was seen in the blank polymer group compared with the control group (tumor only). OncoGel 3.0% and OncoGel 6.0% were effective in delaying the onset of paralysis in the respective study groups.
These findings demonstrate the potential benefit of OncoGel in cases of subtotal resections of metastatic spinal column tumors. OncoGel 6.0% is the most efficacious drug concentration and offers the best therapeutic option in this experimental model. These results provide promise for the development of local chemotherapeutic means to treat spinal metastases.
Risheng Xu, Mohamad Bydon, Ziya L. Gokaslan, Jean-Paul Wolinsky, Timothy F. Witham and Ali Bydon
Epidural steroid injections are relatively safe procedures, although the risk of hemorrhagic complications in patients undergoing long-term anticoagulation therapy is higher. The American Society for Regional Anesthesia and Pain Medicine has specific guidelines for treatment of these patients when they undergo neuraxial anesthetic procedures. In this paper, the authors present a case in which the current American Society for Regional Anesthesia and Pain Medicine guidelines were strictly followed with respect to withholding and reintroducing warfarin and enoxaparin after an epidural steroid injection, but the patient nevertheless developed a spinal epidural hematoma requiring emergency surgical evacuation. The authors compare the case with the 8 other published cases of postinjection epidural hematomas in patients with coagulopathy, and the specific risk factors that may have contributed to the hemorrhagic complication in this patient is analyzed.
Rafael De la Garza Ramos, C. Rory Goodwin, Nancy Abu-Bonsrah, Ali Bydon, Timothy F. Witham, Jean-Paul Wolinsky and Daniel M. Sciubba
The aim of this study was to investigate the incidence of spinal tuberculosis (TB) in the US between 2002 and 2011.
The Nationwide Inpatient Sample database from 2002 to 2011 was used to identify patients with a discharge diagnosis of TB and spinal TB. Demographic and hospital data were obtained for all admissions, and included age, sex, race, comorbid conditions, insurance status, hospital location, hospital teaching status, and hospital region. The incidence rate of spinal TB adjusted for population growth was calculated after application of discharge weights.
A total of 75,858 patients with a diagnosis of TB were identified, of whom 2789 had a diagnosis of spinal TB (3.7%); this represents an average of 278.9 cases per year between 2002 and 2011. The incidence of spinal TB decreased significantly—from 0.07 cases per 100,000 persons in 2002 to 0.05 cases per 100,000 in 2011 (p < 0.001), corresponding to 1 case per 2 million persons in the latter year. The median age for patients with spinal TB was 51 years, and 61% were male; 11.6% were patients with diabetes, 11.4% reported recent weight loss, and 8.1% presented with paralysis. There were 619 patients who underwent spinal surgery for TB, with the most common location being the thoracolumbar spine (61.9% of cases); 50% of patients had instrumentation of 3 or more spinal segments.
During the examined 10-year period, the incidence of spinal TB was found to significantly decrease over time in the US, reaching a rate of 1 case per 2 million persons in 2011. However, the absolute reduction was relatively small, suggesting that although it is uncommon, spinal TB remains a public health concern and most commonly affects male patients approximately 50 years of age. Approximately 20% of patients with spinal TB underwent surgery, most commonly in the thoracolumbar spine.
Scott L. Parker, Risheng Xu, Matthew J. McGirt, Timothy F. Witham, Donlin M. Long and Ali Bydon
The most common spinal procedure performed in the US is lumbar discectomy for disc herniation. Longterm disc degeneration and height loss occur in many patients after lumbar discectomy. The incidence of mechanical back pain following discectomy varies widely in the literature, and its associated health care costs are unknown. The authors set out to determine the incidence of and the health care costs associated with mechanical back pain attributed to segmental degeneration or instability at the level of a prior discectomy performed at their institution.
The authors retrospectively reviewed the data for 111 patients who underwent primary, single-level lumbar hemilaminotomy and discectomy for radiculopathy. All diagnostic modalities, conservative therapies, and operative treatments used for the management of postdiscectomy back pain were recorded. Institutional billing and accounting records were reviewed to determine the billed costs of all diagnostic and therapeutic measures.
At a mean follow-up of 37.3 months after primary discectomy, 75 patients (68%) experienced minimal to no back pain, 26 (23%) had moderate back pain requiring conservative treatment only, and 10 (9%) suffered severe back pain that required a subsequent fusion surgery at the site of the primary discectomy. The mean cost per patient for conservative treatment alone was $4696. The mean cost per patient for operative treatment was $42,554. The estimated cost of treatment for mechanical back pain associated with postoperative same-level degeneration or instability was $493,383 per 100 cases of first-time, single-level lumbar discectomy ($4934 per primary discectomy).
Postoperative mechanical back pain associated with same-level degeneration is not uncommon in patients undergoing single-level lumbar discectomy and is associated with substantial health care costs.
Carlos A. Bagley, Markus J. Bookland, Jonathan A. Pindrik, Tolga Ozmen, Ziya L. Gokaslan, Jean-Paul Wolinsky and Timothy F. Witham
Spinal column metastatic disease affects thousands of cancer patients every year. Radiation therapy frequently represents the primary treatment for this condition. Despite the enormous clinical impact of spinal column metastatic disease, the literature currently lacks an accurate animal model for testing the efficacy of irradiation on spinal column metastases.
After anesthesia was induced, female Fischer 344 rats underwent a transabdominal approach to the ventral vertebral body (VB) of L-6. A 2- to 3-mm-diameter bur hole was drilled for the implantation of a section of CRL-1666 breast adenocarcinoma. After the animals had recovered from the surgery, they underwent fractionated, single-port radiotherapy beginning on postoperative Day 7. Each group of animals underwent five daily fractions of radiation treatment. Group I animals received a total dose of 10 Gy in 200-cGy daily fractions, Group II animals received a total dose of 20 Gy in 400-cGy daily fractions, and Group III animals received a total dose of 30 Gy in 600-cGy daily fractions. A control group of rats with implanted VB lesions did not receive radiation. To test the effects of radiation toxicity alone, additional rats without implanted tumors received radiation treatments in the same fractions as the rats with tumors. Hindlimb function in all rats was rated before and after radiation treatment using the Basso-Beattie-Bresnahan locomotor rating scale. Histological analysis of spinal cord and vertebral column sections was performed after each animal's death.
Functional assessments demonstrated a statistically significant delay in the onset of paresis between the three treatment groups and the control group (tumor implanted but no radiotherapy). The rats in the three treatment groups, however, did not exhibit any significant differences related to hindlimb function. A dose-dependent relationship was found for the percentage of animals who had become paralyzed at the time of death, with all members of the control group and no members of the 30-Gy group exhibiting paralysis. The results of this study do not indicate any overall survival benefit for any level of radiation dose.
These findings demonstrate the efficacy of focal spinal irradiation in delaying the onset of paralysis in a rat metastatic spine tumor model, but without a clear survival benefit. Because of the dose-related toxicity observed in the rats treated with 30 Gy, this effect was most profound for the 20-Gy group. This finding parallels the observed clinical course of spinal column metastatic disease in humans and provides a basis for the future comparison of novel local and systemic treatments to augment the observed effects of focal irradiation.
Matthew J. McGirt, Kaisorn L. Chaichana, April Atiba, Ali Bydon, Timothy F. Witham, Kevin C. Yao and George I. Jallo
Gross-total resection of pediatric intramedullary spinal cord tumor (IMSCT) can be achieved in the majority of cases while preserving long-term neurological function. Nevertheless, postoperative progressive spinal deformity often complicates functional outcome years after surgery. The authors set out to determine whether laminoplasty in comparison with laminectomy has reduced the incidence of subsequent spinal deformity requiring fusion after IMSCT resection at their institution.
The first 144 consecutive patients undergoing resection of IMSCTs at a single institution underwent laminectomy with preservation of facet joints. The next 20 consecutive patients presenting for resection of IMSCTs underwent osteoplastic laminotomy regardless of patient or tumor characteristics. All patients were followed up with telephone interviews corroborated by medical records for the following outcomes: 1) neurological and functional status (modified McCormick Scale [MMS] score and Karnofsky Performance Scale [KPS] score); and 2) development of progressive spinal deformity requiring fusion. The incidence of progressive spinal deformity and the long-term neurological function were compared between the laminectomy and osteoplastic laminotomy cohorts. The means are expressed ± the standard deviation.
Overall, the patients' mean age was 8.6 ± 5 years, and they presented with median MMS scores of 2 (interquartile range [IQR] 2–4). A > 95% resection was achieved in 125 cases (76%). There were no differences (p > 0.10) between patients treated with osteoplastic laminotomy and those treated with laminectomy in terms of the following characteristics: age; sex; duration of symptoms; location of tumor; incidence of preoperative scoliosis (Cobb angle > 10°: 7 [35%] with laminoplasty compared with 49 [34%] with laminectomy); involvement of the cervicothoracic junction (7 [35%] compared with 57 [40%]); thoracolumbar junction (4 [20%] compared with 36 [25%]); tumor size; extent of resection; radiation therapy; histopathological findings; or mean operative spinal levels (7.5 ± 2 compared with 7.5 ± 3). Nevertheless, patients who underwent osteoplastic laminotomy had better median preoperative MMS scores than those treated with laminectomy (2 [IQR 2–2] compared with 2 [IQR 2–4]; p = 0.04). A median of 3.5 years (IQR 1–7 years) after surgery, only 1 patient (5%) in the osteoplastic laminotomy cohort required fusion for progressive spinal deformity, compared with 43 (30%) in the laminectomy cohort (p = 0.027). Adjusting for the inter-cohort difference in preoperative MMS scores, osteoplastic laminotomy was associated with a 7-fold reduction in the odds of subsequent fusion for progressive spinal deformity (odds ratio 0.13, 95% confidence interval 0.02–1.00; p = 0.05). The median MMS and KPS scores were similar between patients who underwent osteoplastic laminotomy and those in whom laminectomy was performed (MMS Score 2 [IQR 2–3] for laminotomy compared with 2 [IQR 2–4] for laminectomy, p = 0.54; KPS Score 90 [IQR 70–100] for laminotomy compared with 90 [IQR 80–90] for laminectomy, p = 0.545) at a median of 3.5 years after surgery.
In the authors' experience, osteoplastic laminotomy for the resection of IMSCT in children was associated with a decreased incidence of progressive spinal deformity requiring fusion but did not affect long-term functional outcome. Laminoplasty used for pediatric IMSCT resection may decrease the incidence of progressive spinal deformity requiring subsequent spinal stabilization in some patients.
Paul E. Kaloostian, Jennifer E. Kim, Ali Bydon, Daniel M. Sciubba, Jean-Paul Wolinsky, Ziya L. Gokaslan and Timothy F. Witham
The authors describe the largest case series of 8 patients with intracranial hemorrhage (ICH) after spinal surgery and identify associated pre-, intra-, and postoperative risk factors in relation to outcome.
The authors retrospectively reviewed the cases of 8 patients treated over 16 years at a single institution and also reviewed the existing literature and collected demographic, treatment, and outcome information from 33 unique cases of remote ICH after spinal surgery.
The risk factors most correlated with ICH postoperatively were the presence of a CSF leak intraoperatively and the use of drains postoperatively with moderate hourly serosanguineous output in the early postoperative period.
Intracranial hemorrhage is a rare complication of spinal surgery that is associated with CSF leakage and use of drains postoperatively, with moderate serosanguinous output. These associations do not justify a complete avoidance of drains in patients with CSF leakage but may guide the treating physician to keep in mind drain output and timing of drain removal, while noting any changes in neurological examination status in the meantime. Additionally, continued and worsening neurological symptoms after spinal surgery may warrant cranial imaging to rule out intracranial hemorrhage, usually within the first 24 hours after surgery. The presence of cerebellar hemorrhage and hydrocephalus indicated a trend toward worse outcome.