Sacral Tarlov perineurial cysts: a systematic review of treatment options.

Tarlov perineurial spinal cysts (TCs) are an underrecognized cause of spinal neuropathic symptoms. TCs form within the sensory nerve root sleeves, where CSF extends distally and can accumulate pathologically. Typically, they develop at the sacral dermatomes where the nerve roots are under the highest hydrostatic pressure and lack enclosing vertebral foramina. In total, 90% of patients are women, and genetic disorders that weaken connective tissues, e.g., Ehlers-Danlos syndrome, convey considerable risk. Most small TCs are asymptomatic and do not require treatment, but even incidental visualizations should be documented in case symptoms develop later. Symptomatic TCs most commonly cause sacropelvic dermatomal neuropathic pain, as well as bladder, bowel, and sexual dysfunction. Large cysts routinely cause muscle atrophy and weakness by compressing the ventral motor roots, and multiple cysts or multiroot compression by one large cyst can cause even greater cauda equina syndromes. Rarely, giant cysts erode the sacrum or extend as intrapelvic masses. Disabling TCs require consideration for surgical intervention. The authors' systematic review of treatment analyzed 31 case series of interventional percutaneous procedures and open surgical procedures. The surgical series were smaller and reported somewhat better outcomes with longer term follow-up but slightly higher risks. When data were lacking, authorial expertise and case reports informed details of the specific interventional and surgical techniques, as well as medical, physical, and psychological management. Cyst-wrapping surgery appeared to offer the best long-term outcomes by permanently reducing cyst size and reconstructing the nerve root sleeves. This curtails ongoing injury to the axons and neuronal death, and may also promote axonal regeneration to improve somatic and autonomic sacral nerve function.

Low thoracic erector spinae plane block for perioperative analgesia in lumbosacral spine surgery: a case series.

PURPOSE: Severe postoperative pain following spine surgery is a significant cause of morbidity, extended length of facility stay, and marked opioid usage. The erector spinae plane (ESP) block anesthetizes the dorsal rami of spinal nerves that innervate the paraspinal muscles and bony vertebra. We describe the use of low thoracic ESP blocks as part of multimodal analgesia in lumbosacral spine surgery. CLINICAL FEATURES: We performed bilateral ESP blocks at the T10 or T12 level in six cases of lumbosacral spine surgery: three lumbar decompressions, two sacral laminoplasties, and one coccygectomy. Following induction of general anesthesia, single-injection ESP blocks were performed in three patients while bilateral continuous ESP block catheters were placed in the remaining three. All six patients had minimal postoperative pain and very low postoperative opioid requirements. There was no discernible motor or sensory block in any of the cases and no interference with intraoperative somatosensory evoked potential monitoring used in two of the cases. CONCLUSIONS: The ESP block can contribute significantly to a perioperative multimodal opioid-sparing analgesic regimen and enhance recovery after lumbosacral spine surgery.

Relief of Cervicogenic Headaches after Single-Level and Multilevel Anterior Cervical Diskectomy: A 5-Year Post Hoc Analysis.

STUDY DESIGN: Prospective study. OBJECTIVE: Because single-level disk arthroplasty or arthrodesis in the lower subaxial spine improves headaches after surgery, we studied whether this effect may be better appreciated after two-level arthroplasty. METHODS: We performed an independent post hoc analysis of two concurrent prospective randomized investigational device exemption trials for cervical spondylosis, one for single-level treatment and the other for two adjacent-level treatments. RESULTS: For the one-level study, baseline mean headache scores significantly improved at 60 months for both the cervical disk arthroplasty (CDA) and anterior cervical diskectomy and fusion (ACDF) groups (p < 0.0001). However, mean improvement in headache scores was not statistically different between the investigational and control groups from 6 months through 60 months. For the two-level study, baseline mean headache scores significantly improved at 60 months for both the CDA and ACDF groups (p < 0.0001). The CDA group demonstrated greater improvement from baseline at all points; this difference was statistically significant at 6, 12, 24, 36, and 48 months but not at 18 and 60 months. CONCLUSION: Both CDA and ACDF at either one or two levels are associated with sustained headache relief from baseline. Patients undergoing two-level arthroplasty had significantly greater improvement in headache at all points except for at 18 and 60 months. This difference in improvement was not observed in patients undergoing single-level arthroplasty. The mechanism of greater headache relief after two-level arthroplasty remains unclear.

Intraoperative Extracorporeal Irradiation for the Treatment of the Meningioma-Infiltrated Calvarium.

Objectives Complete removal of infiltrated bone is required to achieve a Simpson Grade 1 meningioma resection. Reconstruction of the resulting bone defect is typically achieved with a nonnative implant that can result in poor cosmesis, foreign body reaction, or infection. Extracorporeal irradiation and reimplantation of tumorous bone has been used for limb-sparing surgery with excellent results, but this treatment option is not routinely considered in meningioma surgery. We present a case of anterior fossa meningioma with tumorous overlying calvarium that was successfully managed with intraoperative extracorporeal irradiation and reimplantation. Design, Setting, and Participant A 37-year-old woman with persistent chronic headaches was found to have an anterior skull base meningioma with extension into the forehead frontal bone. Concurrently with mass resection, the bone flap was irradiated intraoperatively with 120 Gy. After resection of the tumor, the bone flap was replaced in its native position. Main Outcome Measures and Results Twenty-nine months postoperatively, the patient had an excellent cosmetic outcome with no radiographic evidence of tumor recurrence or significant bone flap resorption. Conclusion Intraoperative extracorporeal irradiation of tumorous calvaria during meningioma surgery is an effective, logistically feasible treatment option to achieve local tumor control and excellent cosmetic outcome.

Headache relief after anterior cervical discectomy: post hoc analysis of a randomized investigational device exemption trial: clinical article.

OBJECT: The authors analyzed headache relief after anterior cervical discectomy. Headache may be relieved after anterior cervical discectomy, but the mechanism is unknown. If headaches were directly referred from upper cervical pathology, more headache relief would be expected from surgery performed at higher cervical levels. If spinal kinesthetics were the mechanism, then headache relief may differ between arthroplasty and fusion. Headache relief after anterior cervical discectomy was quantified by the operated disc level and by the method of operation (arthroplasty vs arthrodesis). METHODS: The authors performed a post hoc analysis of an artificial disc trial. Data on headache pain were extracted from the Neck Disability Index (NDI) questionnaire. RESULTS: A total of 260 patients underwent single-level arthroplasty or arthodesis. Preoperatively, 52% reported NDI headache scores of 3 or greater, compared with only 13%-17% postoperatively. The model-based mean NDI headache score at baseline was 2.5 (95% CI 2.3-2.7) and was reduced by 1.3 points after surgery (95% CI 1.2-1.4, p < 0.001). Higher cervical levels were associated with a greater degree of preoperative headache, but there was no association with headache relief. There was no significant difference in headache relief between arthroplasty and arthrodesis. CONCLUSIONS: Most patients with symptomatic cervical spondylosis have headache as a preoperative symptom (88%). Anterior cervical discectomy with both arthroplasty and arthrodesis is associated with a durable decrease in headache. Headache relief is not related to the level of operation. The mechanism for headache reduction remains unclear.

Use of the O-arm® for skull base resection in a sphenoorbital meningioma.

Intraoperative imaging during skull base surgery allows the surgeon to evaluate surgical results and direct further bone resection prior to closure, avoiding the potential morbidity of inadequate surgical therapy or reoperation. Intraoperative CT (iCT) scanning has become widely available in recent years, but its neurosurgical applications have been limited mostly to spinal and functional operations. We report a patient with a sphenoorbital meningioma with adjacent hyperostosis causing proptosis and optic canal stenosis in which a portable iCT scanner (O-arm(®); Medtronic, Fridley, MN, USA) was used to guide further resection. Postoperatively, the patient experienced resolution of her proptosis, and her vision remains clinically normal. The O-arm(®) can be easily incorporated into standard operating rooms and is useful in tailoring bony skull base resections.

Decompressive craniectomy using gelatin film and future bone flap replacement.

OBJECT: Decompressive craniectomy plays an important role in the management of patients with traumatic brain injury (TBI) and stroke. Risks of decompressive craniectomy include those associated with cranioplasty, and may be related to adhesions that develop between the brain surface and overlying scalp and temporalis muscle. The authors report their institutional experience using a multilayered technique (collagen and gelatin film barriers) to facilitate safe and rapid cranioplasty following decompressive craniectomy. METHODS: The authors conducted a retrospective chart review of 62 consecutive adult and pediatric patients who underwent decompressive craniectomy and subsequent cranioplasty between December 2007 and January 2011. Diagnoses included TBI, ischemic stroke, intraparenchymal hemorrhage, or subarachnoid hemorrhage. A detailed review of clinical charts was performed, including anesthesia records and radiographic study results. RESULTS: The majority of patients underwent unilateral hemicraniectomy (n = 56), with indications for surgery including midline shift (n = 37) or elevated intracranial pressure (n = 25). Multilayered decompressive craniectomy was safe and easy to perform, and was associated with a low complication rate, minimal operative time, and limited blood loss. CONCLUSIONS: Decompressive craniectomy repair using an absorbable gelatin film barrier facilitates subsequent cranioplasty by preventing adhesions between intracranial contents and the overlying galea aponeurotica and temporalis muscle fascia. This technique makes cranioplasty dissection faster and potentially safer, which may improve clinical outcomes. The indications for gelatin film should be expanded to include placement in the epidural space after craniectomy.

Breast-related CSF shunt complications: literature review with illustrative case.

In this article, we discuss and classify breast-related ventriculoperitoneal (VP) cerebrospinal fluid (CSF) shunt complications, and provide a literature review. Shunt complications related to pre-existing breast implants comprise nearly half of the breast-related shunt complications reported thus far. We present a complication of shunt failure in a 61-year-old woman who had previously undergone mastectomies for breast cancer with implant reconstruction. Following shunting, she developed headaches, fever, and right-sided breast swelling and erythma consequent to breast implant rupture, distal shunt migration, and CSF pseudocyst. This case is unique in that it involved rupture of a breast implant from VP shunt insertion. For complication avoidance, neurosurgeons should be aware of the potential pitfalls in shunting patients with breast implants.

Coccygodynia and coccygectomy.

OBJECTIVE: A review of the literature on coccygectomy and our patients was performed to assess the effectiveness of coccygectomy for chronic refractory coccygodynia. METHODS: An English language PubMed search was conducted with the terms "coccygodynia" and "coccygectomy" from January 1980 to January 2012. We retrospectively reviewed the medical records and performed telephone questionnaire on 61 patients who underwent coccygectomy at UCDMC between 1997 and 2009. RESULTS: There were 28 case series from 1980 to 2012 for a total of 742 patients who underwent coccygectomy following failed conservative management. The mean age ranged from 26.4 to 52.8 years. The most common cause was direct trauma (58.5%) with a male:female ratio of 1:5.2. Most patients (84%) had a good to excellent outcome after coccygectomy. The most common complication is wound infection (10.0%). The overall complication rate was 13.3%. Similarly, 84.6% of patients from our own surgical case series reported good to excellent outcomes with 11.5% wound infection. CONCLUSION: Coccygectomy is an effective treatment for chronic refractory coccygodynia. The surgery isrelatively simple to perform but precaution must be taken to avoid wound infection.

Clinical emergence of neurometastatic merkel cell carcinoma: a surgical case series and literature review.

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine neoplasm of possible viral origin and is known for its aggressive behavior. The incidence of MCC has increased in the last 15 years. Merkel cell carcinoma has the potential to metastasize, but rarely involves the central nervous system. Herein, we report three consecutive surgical cases of MCC presenting at a single institution within 1 year. We used intracavitary BCNU wafers (Gliadel(®)) in two cases. Pathological features, including CK20 positivity, consistent with MCC, were present in all cases. We found 33 published cases of MCC with CNS involvement. We suggest that the incidence of neurometastatic MCC may be increasing, parallel to the increasing incidence of primary MCC. We propose a role for intracavitary BCNU wafers in the treatment of intra-axial neurometastatic MCC.

Fluorescence lifetime imaging microscopy for brain tumor image-guided surgery.

We demonstrate for the first time the application of an endoscopic fluorescence lifetime imaging microscopy (FLIM) system to the intraoperative diagnosis of glioblastoma multiforme (GBM). The clinically compatible FLIM prototype integrates a gated (down to 0.2 ns) intensifier imaging system with a fiber-bundle (fiber image guide of 0.5 mm diameter, 10,000 fibers with a gradient index lens objective 0.5 NA, and 4 mm field of view) to provide intraoperative access to the surgical field. Experiments conducted in three patients undergoing craniotomy for tumor resection demonstrate that FLIM-derived parameters allow for delineation of tumor from normal cortex. For example, at 460±25-nm wavelength band emission corresponding to NADH/NADPH fluorescence, GBM exhibited a weaker fluorescence intensity (35% less, p-value<0.05) and a longer lifetime τGBM-Amean=1.59±0.24 ns than normal cortex τNC-Amean=1.28±0.04 ns (p-value<0.005). Current results demonstrate the potential use of FLIM as a tool for image-guided surgery of brain tumors.

Giant intracranial medullary thyroid carcinoma metastasis presenting as apoplexy.

We present a case of a giant sellar and suprasellar skull base-invasive metastasis from a medullary carcinoma of the thyroid gland. Radiographic features were similar to atypical/malignant meningioma or pituitary macroadenoma. Intracranial metastases from medullary thyroid carcinoma are very rare. Unusual features of our case are discussed.

Acute deterioration in occult Chiari malformation following missile spinal trauma. Case report.

Patients with Chiari malformation (CM) Type I typically experience chronic, slowly progressive symptoms. Rarely, however, do they suffer acute neurological deterioration following an iatrogenic decrease in caudal cerebrospinal fluid pressure due to, for example, a lumbar puncture. To our knowledge, acute neurological deterioration following missile spinal injury in CM has not been previously described. The authors report on a 16-year-old girl who was shot in the abdomen and lumbar spine. Although neurologically intact on initial workup, she developed precipitous quadriplegia and apnea in a delayed fashion. Tonsillar herniation with medullary compression and cerebellar infarction was diagnosed on magnetic resonance imaging. Suboccipital decompression resulted in significant neurological improvement. Well-formed tonsillar ectopia diagnosed at surgery suggested a preexisting CM. The authors conclude that missile spinal trauma can precipitate medullary compression and acute neurological decline, especially in patients with preexisting tonsillar ectopia. Immediate operative decompression to relieve impaction at the cervicomedullary junction can result in significant neurological recovery.

Organotypic distribution of stem cell markers in formalin-fixed brain harboring glioblastoma multiforme.

The role of stem cells in the origin, growth patterns, and infiltration of glioblastoma multiforme is a subject of intense investigation. One possibility is that glioblastoma may arise from transformed stem cells in the ventricular zone. To explore this hypothesis, we examined the distribution of two stem cell markers, activating transcription factor 5 (ATF5) and CD133, in an autopsy brain specimen from an individual with glioblastoma multiforme. A 41-year-old male with a right posterior temporal glioblastoma had undergone surgery, radiation, and chemotherapy. The brain was harvested within several hours after death. After formalin fixation, sectioning, and mapping of tumor location in the gross specimen, histologic specimens were prepared from tumor-bearing and grossly normal hemispheres. Fluorescence immunohistochemistry and colorimetric staining were performed for ATF5 and CD133. Both markers co-localized to the ependymal and subependymal zones on the side of the tumor, but not in the normal hemisphere or more rostrally in the affected hemisphere. ATF5 staining was especially robust within the diseased hemisphere in histologically normal ependyma. To our knowledge, this is the first in situ demonstration of stem cell markers in whole human brain. These preliminary results support the hypothesis that some glioblastomas may arise from the neurogenic zone of the lateral ventricle. The robust staining for ATF5 and CD133 in histologically normal ventricular zone suggests that an increase in periventricular stem cell activity occurred in this patient on the side of the tumor, either as a localized response to brain injury or as an integral component of oncogenesis and tumor recurrence.

Trevor disease of the spine. Case report.

The authors report the case of a 15-year-old boy who presented with left shoulder pain and paresthesia of the left hand. Imaging studies revealed an osseous lesion compressing the C-8 nerve root. The patient underwent tumor resection followed by instrumentation-augmented fusion. Histological findings were consistent with osteochondroma. The tumor most likely originated from the articular cartilage between the first rib and T-1 or between C-7 and T-1. The correct diagnosis, therefore, was dysplasia epiphysialis hemimelica (DEH), also known as Trevor disease. To the authors' knowledge, this is the first report of DEH involving the spine.