Edward E. Kerr

Coccygectomy for chronic refractory coccygodynia: clinical case series and literature review: Clinical article

OBJECT Coccygodynia is disabling pain in the coccyx and is usually provoked by sitting or rising from sitting. The diagnosis can be missed by neurosurgeons likely to encounter the disorder, and surgical treatment for coccygodynia has historically been viewed with caution. The authors conducted a retrospective review of 62 successive coccygectomy surgeries for coccygodynia performed at their institution. METHODS Sixty-two consecutive cases of coccygectomy for coccygodynia in 61 unique patients were identified from the surgical database; they had been treated between 1997 and 2009. The authors succeeded in contacting 26 patients for follow-up (42.6%). A retrospective chart review was performed, and a telephone questionnaire was administered to these patients. Data collected included cause, pre- and postoperative visual analog scale, a graded outcome measure, and patient satisfaction. The median follow-up time was 37 months (range 2-133 months). RESULTS The clinical results among the 26 patients with follow-up were as follows: 13 excellent, 9 good, 2 fair, and 2 poor. The overall favorable (excellent and good) outcome after coccygectomy was 84.6%. There were 3 wound infections (11.5%). There were no rectal injuries. An overwhelming majority of patients were satisfied with the procedure. CONCLUSIONS The authors report the results of their clinical case series, which to date is the largest in North America. The results closely concur with previously published case series from Europe. Coccygectomy for chronic intractable coccygodynia is simple and effective, with a low complication rate. A comprehensive literature review and discussion of coccygectomy is provided.

Posterior fossa calcifying pseudoneoplasm of the central nervous system.

Calcifying pseudoneoplasms of the neuraxis are rare, poorly understood masses that may arise throughout the CNS. Although these lesions are generally considered benign and noninfiltrative, reports exist that document growth of these masses on serial plain radiographs. The authors report a case of a posterior fossa calcifying pseudoneoplasm of the neuraxis demonstrating interval development of peritumoral edema on serial MRI. Their findings suggest that these lesions may sometimes behave in a more aggressive manner than commonly thought.

Comparative analysis of the anterior transpetrosal approach with the endoscopic endonasal approach to the petroclival region

OBJECTIVE The endoscopic endonasal approach (EEA) offers direct access to midline skull base lesions, and the anterior transpetrosal approach (ATPA) stands out as a method for granting entry into the upper and middle clival areas. This study evaluated the feasibility of performing EEA for tumors located in the petroclival region in comparison with ATPA. METHODS On 8 embalmed cadaver heads, EEA to the petroclival region was performed utilizing a 4-mm endoscope with either 0° or 30° lenses, and an ATPA was performed under microscopic visualization. A comparison was executed based on measurements of 5 heads (10 sides). Case illustrations were utilized to demonstrate the advantages and disadvantages of EEA and ATPA when dealing with petroclival conditions. RESULTS Extradurally, EEA allows direct access to the medial petrous apex, which is limited by the petrous and paraclival internal carotid artery (ICA) segments laterally. The ATPA offers direct access to the petrous apex, which is blocked by the petrous ICA and abducens nerve inferiorly. Intradurally, the EEA allows a direct view of the areas medial to the cisternal segment of cranial nerve VI with limited lateral exposure. ATPA offers excellent access to the cistern between cranial nerves III and VIII. The quantitative analysis demonstrated that the EEA corridor could be expanded laterally with an angled drill up to 1.8 times wider than the bone window between both paraclival ICA segments. CONCLUSIONS The midline, horizontal line of the petrous ICA segment, paraclival ICA segment, and the abducens nerve are the main landmarks used to decide which approach to the petroclival region to select. The EEA is superior to the ATPA for accessing lesions medial or caudal to the abducens nerve, such as chordomas, chondrosarcomas, and midclival meningiomas. The ATPA is superior to lesions located posterior and/or lateral to the paraclival ICA segment and lesions with extension to the middle fossa and/or infratemporal fossa. The EEA and ATPA are complementary and can be used independently or in combination with each other in order to approach complex petroclival lesions.

Immediate complications associated with high-flow cerebrospinal fluid egress during endoscopic endonasal skull base surgery.

Endoscopic expanded endonasal approaches (EEAs) to the skull base are increasingly being used to address a variety of skull base pathologies. Postoperative CSF leakage from the large skull base defects has been well described as one of the most common complications of EEAs. There are reports of associated formation of delayed subdural hematoma and tension pneumocephalus from approximately 1 week to 3 months postoperatively. However, there have been no reports of immediate complications of high-volume CSF leakage from EEA skull base surgery. The authors describe two cases of EEAs in which complications related to rapid, large-volume CSF egress through the skull base surgical defect were detected in the immediate postoperative period. Preventive measures to reduce the likelihood of these immediate complications are presented.

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.

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.