Anterior Interhemispheric Approach for 100 Tumors in and Around the Anterior Third Ventricle

Neurosurgery 66[ONS Suppl 1]:ons65-ons74, 2010 DOI: 10.1227/01.NEU.0000365550.84124.BB

We report our experience with anterior interhemispheric approach for tumors in and around the anterior third ventricle, including surgical technique, instrumentation, pre- and postoperative hormonal disturbances, and resection rate.

METHODS: One hundred patients with 46 craniopharyngiomas, 12 hypothalamic gliomas, 12 meningiomas, 6 hypothalamic hamartomas, and 24 other lesions were operated on using an anterior interhemispheric approach with or without opening of the lamina terminalis. This surgical approach involves no frontal sinus opening; a narrow (approximately 15–20 mm in width) access between the bridging veins, which is sufficient to remove the tumor totally; and sparing of the anterior communicating artery. Specially designed long bipolar forceps and scissors are necessary for this approach, and concomitant use of angled instruments (endoscope, aspirator, and microforceps) is required frequently. The postsurgical follow-up period varied from 4 months to 18 years. RESULTS: Total removal of the neoplasm was accomplished in 37 of 46 patients with craniopharyngiomas (80.4%), whereas subtotal resection was performed in hypothalamic gliomas. No significant differences in pre- and postoperative hormonal disturbances were observed in 37 craniopharyngiomas and 10 hypothalamic gliomas. There was no operative mortality. Visual acuity was preserved or improved in 68 of 75 patients assessed. The Karnofsky Performance Scale score did not deteriorate in 72 of 75 patients tested.

CONCLUSION: The minimally invasive anterior interhemispheric approach, with or without opening of the lamina terminalis, is useful for removal of tumors in and around the anterior third ventricle, such as craniopharyngiomas and hypothalamic gliomas.

Endoscopic Endonasal Transethmoidal Transcribriform Transfovea Ethmoidalis Approach to the Anterior Cranial Fossa and Skull Base

Neurosurgery 66:1-10, 2010. DOI: 10.1227/01.NEU.0000368395.82329.C4

The anterior skull base, in front of the sphenoid sinus, can be approached using a variety of techniques including extended subfrontal, transfacial, and craniofacial approaches. These methods include risks of brain retraction, contusion, cerebrospinal fluid leak, meningitis, and cosmetic deformity. An alternate and more direct approach is the endonasal, transethmoidal, transcribriform, transfovea ethmoidalis approach.

METHODS: A purely endoscopic, endonasal approach was used to treat a variety of conditions of the anterior skull base arising in front of the sphenoid sinus and between the orbits in a series of 44 patients. A prospective database was used to detail the corridor of approach, closure technique, use of intraoperative lumbar drainage, operative time, and postoperative complications. Extent of resection was determined by a radiologist using volumetric analysis.

RESULTS: Pathology included meningo/encephaloceles (19), benign tumors (14), malignant tumors (9), and infectious lesions (2). Lumbar drains were placed intraoperatively in 20 patients. The CSF leak rate was 6.8% for the whole series and 9% for intradural cases. Leaks were effectively managed with lumbar drainage. Early reoperation for cerebrospinal fluid (CSF) leak occurred in 1 patient (2.2%). There were no intracranial infections. Greater than 98% resection was achieved in 12 of 14 benign and 5 of 9 malignant tumors.

CONCLUSION: The purely endoscopic, endonasal, transethmoidal, transcribriform, transfovea ethmoidalis approach is versatile and suitable for managing a variety of pathological entities. This minimal access surgery is a feasible alternative to transcranial, transfacial, or combined craniofacial approaches to the anterior skull base and anterior cranial fossa in front of the sphenoid sinus. The risk of CSF leak and infection are reasonably low and decrease with experience. Longer follow-up and larger series of patients will be required to validate the long-term efficacy of this minimally invasive approach.

Accuracy of pedicle screw placement in the lumbosacral spine using conventional technique: CT postoperative assessment in 102 consecutive patients

Journal of Neurosurgery: Spine. March 2010.DOI: 10.3171/2009.9.SPINE09261

The goal of this study was to determine the incidence of screw misplacement and complications in a group of 102 patients who underwent transpedicle screw fixation in the lumbosacral spine with conventional open technique and intraoperative fluoroscopy. The results are compared with published data.

Methods: Cases involving 102 consecutive patients (424 inserted screws) were reviewed. Surgery was performed in all cases by the same surgeon’s team, using the same implant, and all results were assessed by means of a specific CT protocol. The screw position was assessed by the authors and an independent observer. Screw position was classified as correct when the screw was completely surrounded by the pedicle cortex, as “cortical encroachment” (questionable violation) if the pedicle cortex could not be visualized, and as “frank penetration” when the screw was outside the pedicular boundaries. Frank penetration was further subdivided as minor (when the edge of the screw thread was up to 2.0 mm outside the pedicle cortex), moderate (2.1–4 mm), and severe (> 4 mm). The incidence of intra- and postoperative complications not related to screw position as well as hardware failures were also registered, with a minimum follow-up duration of 8 months.

Results: The rate of frank pedicle screw misplacement was 5%. The rate of minimal or questionable pedicle wall violation was 2.8%. Among the frank misplacements, 6 were classified as minor, 12 as moderate, and 3 as severe penetration. Two patients (2%) had radicular pain and neurological deficits (inferomedial and inferolateral minor misplacement at L-4 and L-5, respectively), and 5 patients (4.9%) complained only of radicular pain. At the follow-up examination all patients had completely recovered their neurological function and radicular pain was resolved in all cases. The complications not related to screw malposition were 2 pedicle fractures (2% of patients), 1 nerve root injury (1%), and 1 dural laceration (1%). Five patients (4.8%) had postoperative anemia and required transfusions. Superficial or deep wound infection was noted in 3 patients (2.9%). Late hardware failure occurred in 2 patients (2%). One patient developed adjacent segmental instability and required additional surgery to extend the fusion.

Conclusions: Our rates of screw misplacement and complications compare favorably with the lowest rates of the series in which conventional technique was used and are close to the rates reported for image-guided methods. The risk of malpositioning may be reduced with careful preoperative surgical planning, accurate knowledge of the spinal anatomy, surgical experience, and correct indication for conventional surgery. The conventional technique still remains a practical, safe, and effective surgical method for lumbosacral fixation.

Comparison of Tonsillar Retraction and Resection in the Telovelar Approach

Neurosurgery 66[ONS Suppl 1]:ons30-ons40, 2010 DOI: 10.1227/01.NEU.0000348558.35921.4E

OBJECTIVE: To compare the effectiveness of the telovelar approach with tonsillar manipulation for approaching the recesses of the fourth ventricle.

METHODS: A telovelar approach was performed in 8 injected cadaveric heads. Areas of exposure were measured for the superolateral and lateral recesses. Horizontal angles were evaluated by targeting the cerebral aqueduct and medial margin of the lateral recess. Quantitative comparisons were made between the telovelar dissections and various tonsillar manipulations.

RESULTS: Tonsillar retraction provided a comparable exposure of the superolateral recess with tonsillar resection (26.4 ± 17.6 vs 25.2 ± 12.5 mm2, respectively; P = .825). Tonsillar resection significantly increased exposure of the lateral recess compared with tonsillar retraction (31.1 ± 13.3 vs 20.2 ± 11.5 mm2, respectively; P = .002). Compared with tonsillar retraction, the horizontal angle to the lateral recess increased after either contralateral tonsillar retraction (22.7 ± 4.8 vs 36.7 ± 6.5 degrees) or tonsillar resection (22.7 ± 4.8 vs 31.5 ± 7.6 degrees; all adjusted P < .01). The horizontal angle to the cerebral aqueduct increased significantly with tonsillar resection compared with tonsillar retraction (17.6 ± 2.3 vs 13.2 ± 2.8 degrees; P < .001)

CONCLUSION: Compared with tonsillar retraction, tonsillar resection provides a wider corridor to, and a larger area of exposure of, the cerebral aqueduct and lateral recess. Contralateral tonsillar retraction improves access to the lateral recess by widening the surgical view from the contralateral side.

The Combined Supraorbital Keyhole-Endoscopic Endonasal Transsphenoidal Approach to Sellar, Perisellar and Frontal Skull Base Tumors: Surgical Technique

Minim Invas Neurosurg 2009;52: 281 – 286. DOI http://dx.doi.org/10.1055/s-0029-1242776

Extended endoscopic endonasal transsphenoidal approaches (extended EETA) are increasingly being explored for lesions around the sella and the frontal skull base. These approaches, however, require significant surgical expertise and training that can only be obtained in high-volume centers and therefore these approaches are not generalizable to the whole neurosurgical community. Also, these approaches require significant skull base destruction and reconstruction, which comes with a high risk of CSF fistulas.

The aim of this article is to describe a combined supraorbital keyhole-endoscopic endonasal transsphenoidal approach as an alternative surgical strategy to the extended EETA that is easier to perform and that leaves the skull base anatomy more intact.

Technique: Two fairly common neurosurgical approaches, the supraorbital keyhole approach and the endoscopic endonasal transsphenoidal approach, are combined into a single-stage or two-stage surgical procedure. The procedure can be performed as a single neurosurgeon-serial approach and as a two neurosurgeon-parallel simultaneous approach. The philosophy and technique of this combined approach will be described.

Conclusion: The combined supraorbital keyhole-EETA approach can be used without extra surgical training or expertise and with preservation of skull base anatomy for sellar, perisellar and frontal skull base tumors.


Results After Lumbar Decompression With and Without Discectomy: Comparison of the Transspinous and Conventional Approaches

Neurosurgery 66[ONS Suppl 1]:ons152-ons160, 2010 DOI: : 10.1227/01.NEU.0000365826.15986.40

OBJECTIVE: To evaluate the efficacy of the transspinous approach compared with the conventional approach in single-level lumbar laminotomies with and without discectomies.
METHODS: Forty consecutive patients underwent single-level lumbar decompression with or without a discectomy. The first 20 patients underwent surgery by the conventional approach (11 with discectomy and 9 without), and the transspinous approach was used in the remaining 20 patients (11 with discectomy and 9 without). Results between the groups were assessed by comparing the following measures: length of inpatient hospital stay, postoperative pain and analgesia use, estimated blood loss, rate of postoperative disability and complications, and incision length.
RESULTS: The groups did not differ significantly with respect to age, level of pathology, insurance status, or type of analgesia used. The primary outcome was physical disability, measured using the Roland-Morris Disability Questionnaire. The secondary outcome was pain intensity, measured using the Brief Pain Inventory. Patients who underwent the transspinous approach had better outcomes across all measures with significance appreciated in those who underwent transspinous decompression with discectomies. Other statistically significant differences were identified in incision length and postoperative analgesia use at the end of 1 week. No statistically significant differences were identified in the rates of complications, estimated blood loss, inpatient narcotic analgesia use, or length of inpatient hospital stay.
CONCLUSION: Patients who underwent single-level lumbar decompression with or without discectomy had similar outcomes as those who underwent the conventional approach. Although of modest clinical significance, the transspinous approach may afford early mobilization and reduced postoperative pain while providing a satisfactory neurological and functional outcome.

Awake Surgery for Nonlanguage Mapping

Neurosurgery 66:523-529, 2010 DOI: 10.1227/01.NEU.0000364996.97762.73

During the past decade, numerous reports have supported the contribution  of awake mapping in surgical removal of brain lesions in eloquent areas, with a significant  increase of the extent of resection while minimizing the risk of permanent deficit—and  even improving quality of life.

METHODS: Most of these awake procedures were performed in patients with lesions in  language areas, to avoid postoperative aphasia. Surprisingly, mapping of nonlanguage  functions received less attention, despite the possible consequences of deficits other than  aphasia on daily life. Visuospatial and cognitive deficits are reported after brain surgery,  because of more objective and extensive neuropsychological assessments.

RESULTS AND CONCLUSION: This review provides new insights into the indications of  awake craniotomies for nonlanguage mapping in surgery for lesions in areas not related  to language processing.

Overview of disc arthroplasty—past, present and future

Acta Neurochir (2010) 152:393–404. DOI 10.1007/s00701-009-0529-5

Degenerative disc disease is one of the most frequent spinal disorders. The anatomy and the biomechanics of the intervertebral disc are very complex, and the pathomechanics of its degeneration are poorly understood. Despite this complexity and uncertainty, great advances have been made in the field of disc replacement technology, with promising results. Difficulties are continuously being encountered, but careful analysis of the results and intensive research and development will assist in countering these problems. There are approximately 40 clinical reports in the literature describing various aspects of randomised controlled trials involving intervertebral disc arthroplasty. However, the majority of these publications do not provide reliable information, in that they give only interim results and/or the results from just one of the many centres in multicentre studies. Such publications must be interpreted with caution, since they do not always represent the results of the whole study population and may hence be underpowered. We identified six randomised controlled trials that compared the final clinical outcomes of disc arthroplasty and spinal fusion. The present systematic review attempts to give an overview of the current status of disc arthroplasty.

High-grade intramedullary astrocytomas: 30 years’ experience at the Neurosurgery Department of the University of Rome “Sapienza”

J Neurosurg Spine 12:144–153, 2010. (DOI: 10.3171/2009.6.SPINE08910)

The goal in this study was to review a series of patients who underwent surgical removal of intramedul- lary high-grade gliomas, focusing on the functional outcome, recurrence rates, and technical problems continually debated in neurosurgical practice.

Methods. Between December 1976 and December 2006, 22 patients underwent removal of intramedullary high- grade gliomas. Lesions were located in the cervical spinal cord in 12 patients, and in the thoracic cord in 10.

Results. Histological examinations showed 10 Grade III astrocytomas and 12 glioblastomas. Only 2 of the 22 high-grade astrocytomas could be completely removed. The clinical postoperative status worsened in 14 patients (63.6%), was unchanged in 7 patients (31.8%), and there was 1 case of intraoperative death (4.5%). None of the 22 patients showed improvement in their neurological status postoperatively. In this series, excluding the 1 intraopera- tive death, all patients died of progression of the malignancy.

Conclusions. Surgical treatment did not ameliorate the postoperative neurological status; instead, in the majority of cases, it prompted a worsening of the deficit. Radiotherapy and chemotherapy have a little influence on the length of survival. In this series, multimodality treatment of intramedullary high-grade astrocytomas has been shown to increase length of survival without improving the neurological status.

Microsurgical Excision of Colloid Cyst With Favorable Cognitive Outcomes and Short Operative Time and Hospital Stay: Operative Techniques and Analyses of Outcomes With Review of Previous Studies

Neurosurgery: February 2010 – Volume 66 – Issue 2 – p 368–375. doi: 10.1227/01.NEU.0000363858.17782.82

Microsurgical and endoscopic colloid cyst excision differ with regard to operative time, length of hospital stay, and extent of resection.

METHODS: A retrospective review of a single surgeon’s microsurgical colloid cyst resection in 10 consecutive patients was performed. Cyst size, hydrocephalus, symptoms, operative time, postoperative stay, complications, and objective testing of memory, concentration, calculation, and attention (cognition), along with performance at job, were noted.

RESULTS: All 10 patients had complete excision. Mean cyst size, mean operative time, and median postoperative stay were 1.6 cm, 124 minutes, and 3.5 days respectively. The mean operative time from cyst visualization to complete excision was 18 minutes. Follow-up ranged from 6 to 111 months (mean, 49.5 months). There were no recurrences; symptoms (headache, visual and balance problems) improved significantly in 70%. Postoperative cognitive performance, including memory, was the same in 8 patients (5 of whom had preoperative memory problems) and worse in 2 patients who had no preoperative memory problems. The bone flap was removed in 1 patient for wound dehiscence. Hemiparesis in another patient, seen immediately after surgery, completely resolved before discharge. One patient with loculated ventricles and multiple previous shunt revisions had unresolved hydrocephalus after cyst excision.

CONCLUSION: We report the very short operative times and postoperative stay for microsurgery, which are comparable to some endoscopic series. We also report results of objective tests of cognitive performance. With adoption of a callosal incision of 1 cm or less, meticulous dissection around the fornix, and complete excision, acceptable long-term cognitive function and functional performance were achieved. Our results support the microsurgical approach. A larger sample size can more conclusively establish whether it should be chosen over the endoscopic technique.

Supracerebellar Infratentorial Approach to Cavernous Malformations of the Brainstem: Surgical Variants and Clinical Experience With 45 Patients

Neurosurgery 66:389-399, 2010. DOI: 10.1227/01.NEU.0000363702.67016.5D

OBJECTIVE: The supracerebellar infratentorial (SCIT) approach can be performed at the midline (median variant), lateral to the midline (paramedian variant), or at the level of the angle formed by the transverse and sigmoid sinuses (extreme lateral variant). We analyzed our experience with SCIT approaches for the surgical treatment of cavernous malformations of the brainstem (CMBs).

METHODS: Demographic, clinical, radiologic, and surgical data from 45 patients (20 males and 25 females; mean age, 36.2 years) with CMBs surgically removed through SCIT approaches were reviewed retrospectively. Anatomic information was explored using cadaver head dissection.

RESULTS: Twenty-three lesions were in the midbrain, 3 were at the midbrain and extended to the thalamus, 9 were at the pontomesencephalic junction, and 10 were in the upper pons. All patients presented with hemorrhage. The median variant was used in 13 patients, the paramedian variant in 9, and the extreme lateral variant in 23. Intraoperatively, all CMBs were associated with a developmental venous anomaly. At last follow-up, 88% of the patients were the same or better. After a mean follow-up of 20 months, their mean Glasgow Outcome Scale score was 4.1.

CONCLUSION: SCIT approaches provide excellent exposure to CMBs located at the posterior incisural space, not only in the midline but also in the posterolateral surface of the upper pons and midbrain. Careful preoperative planning and neuronavigational assistance are needed to determine the best angle of attack and trajectory for SCIT approaches. Refined microsurgical techniques are paramount to achieve safe surgical removal of CMBs with good outcomes.

Long-term back pain after a single-level discectomy for radiculopathy: incidence and health care cost analysis

J Neurosurg Spine 12:178–182, 2010.(DOI: 10.3171/2009.9.SPINE09410)

Object. The most common spinal procedure performed in the US is lumbar discectomy for disc herniation. Long- term 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.

Methods. 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.

Results. 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 esti- mated 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).

Conclusions. 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.

Intraoperative monitoring of visual evoked potential: introduction of a clinically useful method

DOI: 10.3171/2008.9.JNS08451

Object To obtain a clinically useful method of intraoperative monitoring of visual evoked potentials (VEPs), the authors developed a new light-stimulating device and introduced electroretinography (ERG) to ascertain retinal light stimulation after induction of venous anesthesia.
Methods The new stimulating device consists of 16 red light–emitting diodes embedded in a soft silicone disc to avoid deviation of the light axis after frontal scalp-flap reflection. After induction of venous anesthesia with propofol, the authors performed ERG and VEP recording in 100 patients (200 eyes) who were at intraoperative risk for visual impairment.
Results Stable ERG and VEP recordings were obtained in 187 eyes. In 12 eyes, stable ERG data were recorded but VEPs could not be obtained, probably because all 12 eyes manifested severe preoperative visual dysfunction. The disappearance of ERG data and VEPs in the 13th eye after frontal scalp-flap reflection suggested technical failure attributable to deviation of the light axis. The criterion for amplitude changes was defined as a 50% increase or decrease in amplitude compared with the control level. In 1 of 187 eyes the authors observed an increase in intraoperative amplitude and postoperative visual function improvement. Of 169 eyes without amplitude changes, 17 manifested improved visual function postoperatively, 150 showed no change, and 2 worsened (1 patient with a temporal tumor developed a slight visual field defect in both eyes). Of 3 eyes with intraoperative VEP deterioration and subsequent recovery upon changing the operative maneuver, 1 improved and 2 exhibited no change. The VEP amplitude decreased without subsequent recovery to 50% of the control level in 14 eyes, and all of these developed various degrees of postoperative deterioration of visual function.
Conclusions With the strategy introduced here it is possible to record intraoperative VEPs in almost all patients except in those with severe visual dysfunction. In some patients, postoperative visual deterioration can be avoided or minimized by intraoperative VEP recording. All patients without an intraoperative decrease in the VEP amplitude were without severe postoperative deterioration in visual function, suggesting that intraoperative VEP monitoring may contribute to prevent postoperative visual dysfunction.

Economic impact of improving outcomes of lumbar discectomy

The Spine Journal 10 (2010) 108–116.doi:10.1016/j.spinee.2009.08.453

BACKGROUND: Lumbar discectomy is usually a successful operation with a relatively low cost. Potential adjunctive procedures, such as repairing the anulus fibrosus or nucleus replacements, necessitate a cost-benefit analysis.

PURPOSE: This economic analysis was performed to understand the potential value of advanced implantable technologies designed to improve outcomes after discectomy.

STUDY DESIGN/SETTING: Using an insurance claims–based database, the economics of lessthan- favorable outcomes after lumbar discectomy were studied. Estimates of improved clinical outcomes because of adjunctive surgical procedural items were modeled.

PATIENT SAMPLE: Using Current Procedural Terminology (CPT-4) codes and International Classification of Diseases, Clinical Modification procedure codes (ICD-9 CM), all lumbar discectomy patients were identified in a 6-month period from a large, 2002, commercially available claims-based data set representing 3.1 million insured lives.

OUTCOME MEASURES: Not applicable.

METHODS: Longitudinal data analysis from 3 years (2002–2004) of the database was performed for evidence of claims after the insured’s discectomy (up to 18 months post) as a utilization estimate of surgical and medical treatment resultant of less-than-favorable outcomes. Incidence and cost of secondary operations, medical management, and complications were determined. Using these inputs, an economic model was generated to estimate the effect of improvement in discectomy outcomes.

RESULTS: Of the 494 patients who had a discectomy within a 6-month period, 137 (28%) had subsequent claims that suggested the outcome was less than favorable within 18 months. Patients whose insurance claims included codes for a second operation (n552 patients with 56 operations; 11%) and patients being medically/nonsurgically managed (n585, 17%) were studied. Average reimbursed charges incurred (2006 dollars) of repeated discectomy (80% of cases) was $6,907 and for arthrodesis (20% of cases) was $24,375. Average additional medical treatment cost to diagnose or manage poor outcome requiring another surgery was $3,365. Procedure-related complications within 40 days of surgery were evident in 15% of the group; with additional average cost to manage of $3,939.

CONCLUSIONS: Substantial cost associated with poor discectomy outcomes is often overlooked or underappreciated. Surgical technologies that can improve outcomes of discectomy by 50% to 70% thus improving patient quality of life can be overall cost-neutral between $971 and $1,655 additionally per patient.

Outcome of 132 Operations in 97 Patients With Chordomas of the Craniocervical Junction and Upper Cervical Spine

Neurosurgery 66:59-65, 2010 DOI: 10.1227/01.NEU.0000362000.35742.3D

OBJECTIVE: To study the outcomes of surgery for chordomas of the craniocervical junction and upper cervical spine as well as complication rates, survival, and associated adverse factors.

METHODS: Retrospective review of patients (1982-2007) at 2 European centers who underwent transoral, transfacial, transmandibular, and anterior cervical approaches for excision of chordomas of the craniocervical junction and cervical spine. The χ2 test and Fisher exact test were used to determine significant adverse factors (P < .05), and log-rank survival analysis was used to compare outcome in different groups.

RESULTS: One hundred thirty-two operations were performed in 97 patients. The most common operations were transoral surgeries and maxillotomies. After surgery, neck pain was the same or better in 98.1% of patients. Of the 18.6% of patients who presented with myelopathy, 27.8% improved, 44.4% remained unchanged, and 27.8% deteriorated. Major complication rates were velopharyngeal incompetence, 3.1%; vertebral artery stroke, 1%; wound infection, 3.1%; dysphagia, 3.1%; failure of fixation, 2.1%; sepsis, 3.1%; meningitis, 3.1%; and cerebrospinal fluid leakage, 6.2%. Five- and 10-year overall survivals were 55% and 36%, respectively. Patients who presented to our units for revision surgery, after prior attempts at resection elsewhere, were associated with a worse survival than patients who underwent de novo surgery.

CONCLUSION: We present, to our knowledge, the largest published series of chordomas at the craniocervical junction. Complication rates for these major operations can be minimized at specialist centers, with careful patient selection and counseling. As complete or as radical an operation as possible should be performed at first presentation; the best chance for the patient is the first chance.

Limits of endoscopic treatment of sylvian arachnoid cysts in children

Childs Nerv Syst (2010) 26:155–162. DOI 10.1007/s00381-009-0977-5

The optimal surgical management of sylvian arachnoid cysts is debated. We present our experience in children who were treated endoscopically, focusing on the limits and complications of this approach.

Materials and methods Seventeen children with a temporosylvian arachnoid cyst have been treated using a purely temporal endoscopic approach.

Results In all but one case, the recognition of anatomical landmarks was obtained at the insertion of the endoscope. In one child, the orientation and opening of the basal cisterns were more difficult due to the thickness and opacity of the membranes. Nevertheless, it was possible to perform the cysto-cisternostomy endoscopically in all children with several stomies in 13. In one child, a venous bleeding occurred. There were no other intraoperative complications. There were no postoperative cerebrospinal fluid leaks. In two patients, a symptomatic subdural collection developed which required a transient subdural-peritoneal shunt. No subdural collection was noted on a delayed follow-up (mean, 23 months). Preoperative symptoms related to the mass effect exerted by the cyst resolved in all children. Two children presented a recurrence, 12 and 20 months after endoscopic surgery, respectively. At the redo-endoscopy, the stomies were found to be closed. Their reopening resulted in the disappearance of the symptoms.

Conclusions An endoscopic approach can be used safely in the management of sylvian arachnoid cysts. An effective opening of the deep arachnoid membranes into the basal cisterns could be performed in all patients with the resolution of the preoperative symptoms. However, the long-term efficacy of the stoma needs to be assessed.

Intrasellar Ultrasound in Transsphenoidal Surgery: A Novel Technique

Neurosurgery 66:173-186, 2010. doi: 10.1227/01.NEU.0000360571.11582.4F

OBJECTIVE: Residual tumor masses are common after transsphenoidal surgery. The risk of a residual mass increases with tumor size and parasellar or suprasellar growth. Transsphenoidal surgery is usually performed without image guidance. We aimed to investigate a new technical solution developed for intraoperative ultrasound imaging during transsphenoidal surgery, with respect to potential clinical use and the ability to identify neuroanatomy and tumor.

METHODS: In 9 patients with pituitary macroadenomas, intrasphenoidal and intrasellar ultrasound was assessed during transsphenoidal operations. Ultrasound B-mode, power-Doppler and color-Doppler images were acquired using a small prototype linear array, side-looking probe. The long probe tip measures only 3 × 4 mm. We present images and discuss the potential of intrasphenoidal and intrasellar and ultrasound in transsphenoidal surgery.

RESULTS: We present 2-dimensional, high-resolution ultrasound images. A small side-looking, high-frequency ultrasound probe can be used to ensure orientation in the midline for the surgical approach to identify important neurovascular structures to be avoided during surgery and for resection control and identification of normal pituitary tissue. The image resolution is far better than what can be achieved with current clinical magnetic resonance imaging technology.

CONCLUSION: We believe that the concept of intrasellar ultrasound can be further developed to become a flexible and useful tool in transsphenoidal surgery.

Meningiomas of the ventral foramen magnum and lower clivus: factors influencing surgical morbidity, the extent of tumour resection, and tumour recurrence

Acta Neurochir (2010) 152:79–86 DOI 10.1007/s00701-009-0511-2

Purpose To identify an appropriate surgical approach for meningiomas of the foramen magnum and lower clivus and determine the factors influencing the surgical outcomes. Method The study involved 23 patients with foramen magnum or lower clival meningiomas (8 men, 15 women; average age, 56 years; range, 26–70 years) treated at Keio University Hospital between 1991 and 2008. Their clinical data were retrospectively reviewed with regard to the surgical approaches and outcomes. The average follow-up duration was 42.8 months, the mean tumour size, 25.9 mm (range, 12.0–50.0 mm).

Findings The tumours most commonly originated in the anterolateral rim of the foramen magnum. In 12 cases with lateral compression of the brain stem, the tumours were resected via the suboccipital approach with C1 laminectomy. The transcondylar approach was adopted in 11 cases where the tumour was located on the anterior rim of the foramen magnum. Four patients required epidural drilling of the jugular tubercle. Gross total resection was achieved in 15 cases (62.5%), the resection rate being lowest in cases of tumour extension to the lower clivus. The transient and permanent morbidity rates were 30.4% and 17.4%, respectively. Logistic regression analysis revealed that extension to the lower clivus (noted in 6 of 23 patients) was a statistically significant, independent factor influencing the permanent morbidity rate (p = 0.005).

Conclusions Selecting an appropriate surgical approach considering the tumour location resulted in a good surgical outcome. However, tumour extension to the lower clivus strongly influenced the morbidity and tumour radicality.

Extended transsphenoidal approach for pituitary adenomas invading the anterior cranial base, cavernous sinus, and clivus: a single-center experience with 126 consecutive cases

J Neurosurg 112:108–117, 2010. (DOI: 10.3171/2009.3.JNS0929)

The standard transsphenoidal approach has been successfully used to resect most pituitary adenomas. However, as a result of the limited exposure provided by this procedure, complete surgical removal of pituitary adenomas with parasellar or retrosellar extension remains problematic. By additional bone removal of the cranial base, the extended transsphenoidal approach provides better exposure to the parasellar and clival region compared with the standard approach. The authors describe their surgical experience with the extended transsphenoidal approach to remove pituitary adenomas invading the anterior cranial base, cavernous sinus (CS), and clivus. Methods. Retrospective analysis was performed in 126 patients with pituitary adenomas that were surgically treated via the extended transsphenoidal approach between September 1999 and March 2008. There were 55 male and 71 female patients with a mean age of 43.4 years (range 12–75 years). There were 82 cases of macroadenoma and 44 cases of giant adenoma. Results. Gross-total resection was achieved in 78 patients (61.9%), subtotal resection in 43 (34.1%), and partial resection in 5 (4%). Postoperative complications included transient cerebrospinal rhinorrhea (7 cases), incomplete cranial nerve palsy (5), panhypopituitarism (5), internal carotid artery injury (2), monocular blindness (2), permanent diabetes insipidus (1), and perforation of the nasal septum (2). No intraoperative or postoperative death was observed. Conclusions. The extended transsphenoidal approach provides excellent exposure to pituitary adenomas invading the anterior cranial base, CS, and clivus. This approach enhances the degree of tumor resection and keeps postoperative complications relatively low. However, radical resection of tumors that are firm, highly invasive to the CS, or invading multidirectionally remains a big challenge. This procedure not only allows better visualization of the tumor and the neurovascular structures but also provides significant working space under the microscope, which facilitates intraoperative manipulation. Preoperative imaging studies and new techniques such as the neuronavigation system and the endoscope improve the efficacy and safety of tumor resection.


The Efficacy of Plate Construct Augmentation Versus Cage Alone in Anterior Cervical Fusion

Spine 2009 Dec 15;34(26):2886-92.DOI: 10.1097/BRS.0b013e3181b64f2c

Study Design. Retrospective study.
Objective. To compare the efficacy of anterior cervical discectomy and fusion with cage alone (ACDF-CA) with cage and plate construct (ACDF-CPC) in regards to fusion rate, radiologic and clinical outcomes.
Summary of Background Data. ACDF-CA has shown good results; however, debate exists regarding the high rate of complications such as pseudarthrosis, subsidence, and local kyphosis. In an attempt to avoid these complications, the authors have performed ACDF with cage and plate construct (ACDF-CPC).
Methods. A total of 78 consecutive patients who underwent 1- or 2-level ACDF-CA or ACDF-CPC suffering from cervical radiculopathy were divided into 2 groups; Group A (n = 38) underwent ACDF-CA; Group B (n = 40) underwent ACDF-CPC. Fusion rate, segmental kyphosis, disc height, and subsidence rate were assessed by radiographs. Clinical outcomes were assessed using Robinson criteria.
Results. Solid fusion was achieved in 78.9% (30/38) of subjects in group A compared to 97.5% (39/40) of subjects in group B (P = 0.01). Segmental kyphosis was noted in 42.1% (16/38) in group A compared with 10% (4/40) in group B (P < 0.01). There was a significant decrease in disc height in group A compared to group B (P < 0.05). Subsidence occurred in 32.3% (19/59 levels) of group A compared with 9.7% (6/62 levels) of group B (P < 0.01). Clinical outcomes were similar for both treatment groups. The pseudarthrosis rate in group A was higher than that in group B (P = 0.01). Revision surgery was required in 10.5% (4/38) of group A, whereas none of group B required reoperation (P < 0.01).
Conclusion. The use of cage and plate construct in 1- or 2-level ACDF results in a more lordotic alignment, an increased disc height, a higher fusion rate, a lower subsidence rate, and a lower complication rate than that of cage alone; however, there is no significant difference in clinical outcome between groups