Neurosurgery Blog

Neurosurg Rev (2013) 36:39–44

The cochlear nerve is most commonly located on the caudoventral portion of the capsule of vestibular schwannomas and rarely on the dorsal portion. In such a condition, total removal of the tumor without cochlear nerve dysfunction is extremely difficult.

The purpose of our study was to identify the frequency of this anatomical condition and the status of postoperative cochlear nerve function; we also discuss the preoperative radiological findings.

The study involved 114 patients with unilateral vestibular schwannomas operated on via a retrosigmoid (lateral suboccipital) approach. Locations of the cochlear nerve on the tumor capsule were ventral, dorsal, caudal, and rostral. Ventral and dorsal locations were further subdivided into rostral, middle, and caudal third of the tumor capsule. The postoperative cochlear nerve function and preoperative magnetic resonance (MR) findings were reviewed retrospectively.

In 56 patients that had useful preoperative hearing, useful hearing was retained in 50.0 % (28 of 56) of patients after surgery. The cochlear nerve was located on the dorsal portion of the tumor capsule in four patients (3.5 %), and useful hearing was preserved in only one of these patients (25 %) in whom the tumor had been partially resected.

This tumor-nerve anatomical relationship was identified in all tumors of <2 cm at preoperative MR cisternography. MR cisternography has the potential to identify the tumor–nerve anatomical relationship, especially in small-sized tumors that usually require therapeutic intervention that ensures hearing preservation. Hence, careful evaluation of the preoperative MR cisternography is important in deciding the therapeutic indications.

Neurosurgery 72:42–46, 2013

Jugular foramen schwannomas are uncommon and surgically challenging lesions.

OBJECTIVE: To determine the importance of surgical technique on morbidity and recurrence of jugular foramen schwannomas.

METHODS: A retrospective review and case-control analysis of a single-senior-surgeon series of 81 patients with surgically treated jugular foramen schwannomas was performed, focusing on operative technique. Patients undergoing an aggressive, total tumor resection (series 1) were compared with those undergoing more conservative resection focusing on preserving the pars nervosa (series 2).

RESULTS: There was a statistically significant (P = .04) decrease in permanent deficits of the cranial nerve 9/10 complex with a conservative technique. Recurrence was seen in 3 patients (5.7%) in series 1 and in 3 patients (10.7%) in series 2 (P = .36). Recurrence was treated with reoperation in 1 patient, radiation in 1 patient, and observation in the others.

CONCLUSION: Although radical gross total resection is desirable, it is not optimal for cranial nerve preservation in patients with jugular foramen schwannomas. A more conservative approach resulted in a statistically significant decrease in lower cranial nerve deficits. There was a nonstatistically significant trend toward increasing recurrence, which may be treated with multiple modality therapy in the modern era.

Neurosurgery 71[ONS Suppl 2]:ons308–ons314, 2012

The endoscopic endonasal approach (EEA) has developed as an emerging surgical corridor to the craniovertebral junction (CVJ). In addition to understanding its indications and surgical anatomy, the ability to predict its inferior limit is vital for optimal surgical planning.

OBJECTIVE: To develop a method that accurately predicts the inferior limit of the EEA on the CVJ radiologically and to compare this with other currently used methods.

METHODS: Predissection computerized tomographic scans of 9 cadaver heads were used to delineate a novel line, the naso-axial line (NAxL), to predict the inferior EEA limit on the upper cervical spine. A previously described method with the use of the nasopalatine line (NPL or Kassam line) was also used. On computerized tomographic scans obtained following dissection of the EEA, the predicted inferior limits were compared with the actual extent of dissection.

RESULTS: The postdissection inferior EEA limit ranged from the dens tip to the upper half of the C2 body, which matched the limit predicted by NAxL, with no statistically significant difference between them. In contrast to the NAxL, the NPL predicted a significantly lower EEA limit (P , .001), ranging from the lower half of the C2 body to the superior end plate of C3.

CONCLUSION: The novel NAxL more accurately predicts the inferior limit of the EEA than the NPL. This method, which can be easily used on preoperative sagittal scans, accounts for variations in patients’ anatomy and can aid surgeons in the assessment of the EEA to address caudal CVJ pathology.

Neurosurg Rev (2012) 35:573–582

In this article, the authors are presenting their experience and the results with the surgical treatment of intraorbital intraconal tumors based on a review of 33 constitutive cases. Our data were evaluated in comparison to other major series, and possible factors that might influence surgical outcome and survival are discussed. Thirty-three patients diagnosed with intraorbital intraconal tumors between 1998 and 2009 were treated by transcranial approach. Of these patients, there were 14 males (42.4 %) and 19 females (57.8 %). The age ranged between 2 and 70 years (mean036±16.6 years). The follow-up period ranged between 2 and 13 years (mean07.3±3.2 years). The most common presenting symptoms were exophthalmus and decreased visual acuity, which was seen in 21 (63.6 %) and 19 patients (57.6 %), respectively. Total resection was achieved in 23 patients (69.7 %) while subtotal resection was done in ten patients (30.3 %). Cavernoma and optic nerve sheath meningioma were the most common histologic variants, which were found in 11 (33.3 %) and 10 (30.3 %) patients, respectively. In the long-term follow-up, 54.5 % of the patients showed total ophthalmologic improvement, 9.1 % showed partial improvement, 21.2 % demonstrated unchanged ophthalmologic status, and 15.2 % showed worse ophthalmologic outcome.

Transcranial approach for the treatment of intraorbital intraconal tumors is an effective approach for the management of these pathologies. The effectiveness is clearly demonstrated by the clinical results and outcomes of these patients’ groups.

Neurosurg Rev (2012) 35:593–599

In retrosigmoid craniotomy, neurosurgeons usually depend on surface landmarks and their experience to evaluate the position of transverse-sigmoid sinus junction (TSSJ) and place an appropriate initial burr-hole, which is not accurate each time because of variability in different craniums. The authors introduce a simple procedure based on 3D computed tomography (CT) to localize the TSSJ in retrosigmoid craniotomy.

Eighteen patients who underwent retrosigmoid craniotomy were analyzed. On the internal view of skull in 3D CT image, a simulative burr-hole was placed on the margin of transverse-sigmoid sinus groove junction. Then, on the external view of skull in 3D CT image, the center of the simulative burr-hole was marked and a coordinate system was established based on a line connected the digastric point and the asterion. Then the coordinate of the burr-hole’s center was measured in this coordinate system.

In operation, the burr-hole was placed according to the coordinate measured previously and craniotomy was performed. The margin of TSSJ was exposed in each case. No damage of venous sinus was encountered. Post-operative skull base CT demonstrated a good match between the actual and predicted burr-hole and bone defects only existed along the cut line.

This simple method could help in localizing the TSSJ and avoiding the risk of sinus injury and reducing the bone defect. It is sufficiently precise for practical application at surgical planning.

J Neurosurg 117:654–665, 2012

Surgery for giant anterior clinoidal meningiomas that invade vital neurovascular structures surrounding the anterior clinoid process is challenging. The authors present their skull base technique for the treatment of giant anterior clinoidal meningiomas, defined here as globular tumors with a maximum diameter of 5 cm or larger, centered around the anterior clinoid process, which is usually hyperostotic.

Methods. Between 2000 and 2010, the authors performed 23 surgeries in 22 patients with giant anterior clinoidal meningiomas. They used a skull base approach with extradural unroofing of the optic canal, extradural clinoidectomy (Dolenc technique), transdural debulking of the tumor, early optic nerve decompression, and early identification and control of key neurovascular structures.

Results. The mean age at surgery was 53.8 years. The mean tumor diameter was 59.2 mm (range 50–85 mm) with cavernous sinus involvement in 59.1% (13 of 22 patients). The tumor involved the prechiasmatic segment of the optic nerve in all patients, invaded the optic canal in 77.3% (17 of 22 patients), and caused visual impairment in 86.4% (19 of 22 patients). Total resection (Simpson Grade I or II) was achieved in 30.4% of surgeries (7 of 23); subtotal and partial resections were each achieved in 34.8% of surgeries (8 of 23). The main factor precluding total removal was cavernous sinus involvement. There were no deaths. The mean Glasgow Outcome Scale score was 4.8 (median 5) at a mean of 56 months of follow-up. Vision improved in 66.7% (12 of 18 patients) with consecutive neuroophthalmological examinations, was stable in 22.2% (4 of 18), and deteriorated in 11.1% (2 of 18). New deficits in cranial nerve III or IV remained after 8.7% of surgeries (2 of 23).

Conclusions. This modified surgical protocol has provided both a good extent of resection and a good neurological and visual outcome in patients with giant anterior clinoidal meningiomas.

Neurosurgery 71[ONS Suppl 1]:ons146–ons159, 2012

The jugular tubercle is a rounded bony prominence that arises from the inferolateral margin of the clivus. In a previous publication, we described the surgical anatomy of the expanded endonasal approach to the jugular tubercle.

OBJECTIVE: To illustrate the translation of laboratory work to the operating room describing the anatomic and technical nuances of the endonasal approach to the jugular tubercle.

METHODS: We review the relevant surgical anatomy needed to perform an endonasal approach to the jugular tubercle, and we select 4 different lesions to illustrate the application of our laboratory findings.

RESULTS: In the first case, exposure and partial drilling of the jugular tubercle was critical to gain an adequate corridor to the meningioma, particularly to its inferolateral margin. This allowed for early devascularization, safe extracapsular dissection, and preservation of surrounding neurovascular structures. In addition, the jugular tubercle was hyperostotic and its resection, along with generous dural removal, provided a grade I Simpson tumor resection. In the second (chondrosarcoma) and third (chordoma) cases, the jugular tubercle was infiltrated by tumor, and consequently its complete resection was essential to achieve total tumor removal. In the last case, an unusual adrenocorticotropic hormone-secreting adenoma recurrence at the jugular tubercle region, the technical modification of the transclival approach presented here was successfully applied to achieve complete resection and Cushing disease remission.

CONCLUSION: The transjugular tubercle variant of the expanded endonasal transclival approach allows for direct access to ventrolateral lesions in the inferior clival/petroclival region with no cerebral or cerebellar retraction, or cranial nerve manipulation during the approach.

Neurosurg Focus 33 (3):E14, 2012

Various studies report outcomes of vestibular schwannoma (VS) surgery, but few studies have compared outcomes across the various approaches. The authors conducted a systematic review of the available data on VS surgery, comparing the different approaches and their associated complications.

Methods. MEDLINE searches were conducted to collect studies that reported information on patients undergoing VS surgery. The authors set inclusion criteria for such studies, including the availability of follow-up data for at least 3 months, inclusion of preoperative and postoperative audiometric data, intraoperative monitoring, and reporting of results using established and standardized metrics. Data were collected on hearing loss, facial nerve dysfunction, persistent postoperative headache, CSF leak, operative mortality, residual tumor, tumor recurrence, cranial nerve (CN) dysfunction involving nerves other than CN VII or VIII, and other neurological complications. The authors reviewed data from 35 studies pertaining to 5064 patients who had undergone VS surgery.

Results. The analyses for hearing loss and facial nerve dysfunction were stratified into the following tumor categories: intracanalicular (IC), size (extrameatal diameter) < 1.5 cm, size 1.5–3.0 cm, and size > 3.0 cm. The middle cranial fossa approach was found to be superior to the retrosigmoid approach for hearing preservation in patients with tumors < 1.5 cm (hearing loss in 43.6% vs 64.3%, p < 0.001). All other size categories showed no significant difference between middle cranial fossa and retrosigmoid approaches with respect to hearing loss. The retrosigmoid approach was associated with significantly less facial nerve dysfunction in patients with IC tumors than the middle cranial fossa method was; however, neither differed significantly from the translabyrinthine corridor (4%, 16.7%, 0%, respectively, p < 0.001). The middle cranial fossa approach differed significantly from the translabyrinthine approach for patients with tumors < 1.5 cm, whereas neither differed from the retrosigmoid approach (3.3%, 11.5%, and 7.2%, respectively, p = 0.001). The retrosigmoid approach involved less facial nerve dysfunction than the middle cranial fossa or translabyrinthine approaches for tumors 1.5–3.0 cm (6.1%, 17.3%, and 15.8%, respectively; p < 0.001). The retrosigmoid approach was also superior to the translabyrinthine approach for tumors > 3.0 cm (30.2% vs 42.5%, respectively, p < 0.001). Postoperative headache was significantly more likely after the retrosigmoid approach than after the translabyrinthine approach, but neither differed significantly from the middle cranial fossa approach (17.3%, 0%, and 8%, respectively; p < 0.001). The incidence of CSF leak was significantly greater after the retrosigmoid approach than after either the middle cranial fossa or translabyrinthine approaches (10.3%, 5.3%, 7.1%; p = 0.001). The incidences of residual tumor, mortality, major non-CN complications, residual tumor, tumor recurrence, and dysfunction of other cranial nerves were not significantly different across the approaches.

Conclusions. The middle cranial fossa approach seems safest for hearing preservation in patients with smaller tumors. Based on the data, the retrosigmoid approach seems to be the most versatile corridor for facial nerve preservation for most tumor sizes, but it is associated with a higher risk of postoperative pain and CSF fistula. The translabyrinthine approach is associated with complete hearing loss but may be useful for patients with large tumors and poor preoperative hearing.

Neurosurg Focus 33 (3):E15, 2012

Removal of vestibular schwannomas (VSs, or acoustic neuromas) remains one of the most challenging operations in neurosurgery. Giant or huge tumors (> 5 cm) heighten these challenges, and technical nuances play a special role in maximizing tumor resection while minimizing complications.

In this article, the senior author describes his technical experience with microsurgical excision of giant VSs. The accompanying video further illustrates these details.

Neurosurg Focus 33 (3):E14, 2012

Various studies report outcomes of vestibular schwannoma (VS) surgery, but few studies have compared outcomes across the various approaches. The authors conducted a systematic review of the available data on VS surgery, comparing the different approaches and their associated complications.

Methods. MEDLINE searches were conducted to collect studies that reported information on patients undergoing VS surgery. The authors set inclusion criteria for such studies, including the availability of follow-up data for at least 3 months, inclusion of preoperative and postoperative audiometric data, intraoperative monitoring, and reporting of results using established and standardized metrics. Data were collected on hearing loss, facial nerve dysfunction, persistent postoperative headache, CSF leak, operative mortality, residual tumor, tumor recurrence, cranial nerve (CN) dysfunction involving nerves other than CN VII or VIII, and other neurological complications. The authors reviewed data from 35 studies pertaining to 5064 patients who had undergone VS surgery.

Results. The analyses for hearing loss and facial nerve dysfunction were stratified into the following tumor categories: intracanalicular (IC), size (extrameatal diameter) < 1.5 cm, size 1.5–3.0 cm, and size > 3.0 cm. The middle cranial fossa approach was found to be superior to the retrosigmoid approach for hearing preservation in patients with tumors < 1.5 cm (hearing loss in 43.6% vs 64.3%, p < 0.001). All other size categories showed no significant difference between middle cranial fossa and retrosigmoid approaches with respect to hearing loss. The retrosigmoid approach was associated with significantly less facial nerve dysfunction in patients with IC tumors than the middle cranial fossa method was; however, neither differed significantly from the translabyrinthine corridor (4%, 16.7%, 0%, respectively, p < 0.001). The middle cranial fossa approach differed significantly from the translabyrinthine approach for patients with tumors < 1.5 cm, whereas neither differed from the retrosigmoid approach (3.3%, 11.5%, and 7.2%, respectively, p = 0.001). The retrosigmoid approach involved less facial nerve dysfunction than the middle cranial fossa or translabyrinthine approaches for tumors 1.5–3.0 cm (6.1%, 17.3%, and 15.8%, respectively; p < 0.001). The retrosigmoid approach was also superior to the translabyrinthine approach for tumors > 3.0 cm (30.2% vs 42.5%, respectively, p < 0.001). Postoperative headache was significantly more likely after the retrosigmoid approach than after the translabyrinthine approach, but neither differed significantly from the middle cranial fossa approach (17.3%, 0%, and 8%, respectively; p < 0.001). The incidence of CSF leak was significantly greater after the retrosigmoid approach than after either the middle cranial fossa or translabyrinthine approaches (10.3%, 5.3%, 7.1%; p = 0.001). The incidences of residual tumor, mortality, major non-CN complications, residual tumor, tumor recurrence, and dysfunction of other cranial nerves were not significantly different across the approaches.

Conclusions. The middle cranial fossa approach seems safest for hearing preservation in patients with smaller tumors. Based on the data, the retrosigmoid approach seems to be the most versatile corridor for facial nerve preservation for most tumor sizes, but it is associated with a higher risk of postoperative pain and CSF fistula. The translabyrinthine approach is associated with complete hearing loss but may be useful for patients with large tumors and poor preoperative hearing.

Neurosurg Focus 32 (6):E7, 2012. DOI: 10.3171/2012.5.FOCUS1255

Extended endoscopic endonasal approaches have allowed for a minimally invasive solution for removal of a variety of ventral skull base lesions, including intradural tumors. Depending on the location of the pathological entity, various types of surgical corridors are used, such as transcribriform, transplanum transtuberculum, transsellar, transclival, and transodontoid approaches. Often, a large skull base dural defect with a high-flow CSF leak is created after endoscopic skull base surgery. Successful reconstruction of the cranial base defect is paramount to separate the intracranial contents from the paranasal sinus contents and to prevent postoperative CSF leakage. The vascularized pedicled nasoseptal flap (PNSF) has become the workhorse for cranial base reconstruction after endoscopic skull base surgery, dramatically reducing the rate of postoperative CSF leakage since its implementation.

In this report, the authors review the surgical technique and describe the operative nuances and lessons learned for successful multilayered PNSF reconstruction of cranial base defects with high-flow CSF leaks created after endoscopic skull base surgery. The authors specifically highlight important surgical pearls that are critical for successful PNSF reconstruction, including target-specific flap design and harvesting, pedicle preservation, preparation of bony defect and graft site to optimize flap adherence, multilayered closure technique, maximization of the reach of the flap, final flap positioning, and proper bolstering and buttressing of the PNSF to prevent flap dehiscence. Using this technique in 93 patients, the authors’ overall postoperative CSF leak rate was 3.2%.

An illustrative intraoperative video demonstrating the reconstruction technique is also presented.

Neurosurg Focus 32 (6):E8, 2012. (http://thejns.org/doi/abs/10.3171/2012.4.FOCUS1258)

Methods for repairing middle fossa CSF (MFCSF) leaks have varied and yielded mixed results. The objective of this study was to evaluate the safety and durability of the authors’ repair technique using a novel combination of 3 synthetic materials.

Methods. The authors performed a retrospective case review of patients treated for CSF leaks between January 2009 and September 2011. Eight patients were found to have undergone middle fossa craniotomies for CSF leaks. Inclusion criteria for the study included age greater than 18 years, neuroimaging-documented temporal bone defect, and symptoms consistent with CSF leaks or gross CSF otorrhea. Seven patients, 3 men and 4 women, met the inclusion criteria, and their charts were reviewed. Hydroxyapatite cement, collagen-based dural substitute matrix, and polyethylene glycol hydrogel sealant were used in all patients for the repair.

Results. In all patients the MFCSF leaks were successfully repaired. Initial presenting symptoms included CSF otorrhea in 4 patients (57.1%), hearing loss in 3 (42.9%), and CSF rhinorrhea in 1 (14.3%). The mean follow-up duration was 12 months (range 5–33 months). In 1 patient an epidural hematoma developed at the operative site on postoperative Day 2, and in another patient a superficial wound dehiscence occurred on postoperative Day 48. During the follow-up period, the authors found no evidence of wound infections, neurovascular damage, or CSF leakage requiring reoperation.

Conclusions. The middle fossa approach involving a combination of hydroxyapatite cement, collagen-based dural substitute matrix, and polyethylene glycol hydrogel sealant is a safe, effective method for repairing MFCSF leaks. The combination of synthetic materials provides an alternative to existing materials for skull base surgeons.

Neurosurgery 70[ONS Suppl 2]:ons192–ons201, 2012 DOI: 10.1227/NEU.0b013e31823583a1

The middle fossa approach and extended middle fossa approach, also known as the anterior transpetrosal approach, are cranial base techniques for addressing small vestibular schwannomas, medial temporal bone lesions, midbasilar trunk aneurysms, and selected petroclival lesions.

OBJECTIVE: To provide an outline of a number of technical nuances that are important to correct application of these approaches, maximizing exposure, and limiting potential morbidity.

METHODS: Via a temporal craniotomy, the petrous apex is removed in variable degrees, depending on the exposure requirements of the lesion. The technique is described in detail with appropriate nuances of the technique provided.

RESULTS: The described nuances of technique in the performance of the approaches have resulted in successful application of these techniques in a significant number of cases.

CONCLUSION: Significant familiarity and practice with these surgical approach techniques are critical to applying them safely to clinical problems. A number of technical details can assist the surgeon in achieving optimal exposure and limited morbidity.

Neurosurgery 70:1504–1519, 2012 DOI: 10.1227/NEU.0b013e31824a36e8

Various surgical approaches for the removal of tuberculum sellae meningiomas (TSMs) have previously been described.

OBJECTIVE: To assess the reliability and safety of the lateral supraorbital (LSO) approach to remove TSMs.

METHODS: We identified all TSM patients operated on at the Department of Neurosurgery at Helsinki University Central Hospital, Finland, by the senior author (J.H.) using the LSO approach between September 1997 and August 2010. We retrospectively analyzed the clinical data, radiological findings, surgical treatment, histology, and outcome of patients and discuss the operative technique.

RESULTS: Apparent complete tumor removal was achieved in 45 patients (87%). Of 42 patients, preexisting visual deficit improved in 22, remained the same in 13, and worsened in 7, and de novo visual deficit occurred in 1 patient. At 3 months postdischarge, 47 patients (90%) had a good recovery, 4 (8%) were moderately disabled, and 1 (2%) died 40 days after surgery of unexplained cardiac arrest. Seven patients (13%) had minimal residual tumors, 2 of which required reoperation. During the median follow-up of 59 months (range, 1-133 months), tumor recurred in 1 of the patients who had undergone a second operation.

CONCLUSION: TSMs of all sizes can be removed via the LSO approach with minimal morbidity and mortality. Low-power or no coagulation is recommended near the optic nerves and the optic chiasm to preserve their vascular support from the internal carotid artery perforators. Our results are comparable to those obtained using more extensive and time-consuming approaches. We recommend the LSO approach to remove TSMs.

Neurosurg Focus 32 (6):E5, 2012. (http://thejns.org/doi/abs/10.3171/2012.3.FOCUS1267)

Lateral sphenoid encephaloceles of the Sternberg canal are rare entities and usually present with spontaneous CSF rhinorrhea. Traditionally, these were treated via transcranial approaches, which can be challenging given the deep location of these lesions. However, with advancements in endoscopic skull base surgery, including improved surgical exposures, angled endoscopes and instruments, and novel repair techniques, these encephaloceles can be resected and successfully repaired with purely endoscopic endonasal approaches.

In this report, the authors review the endoscopic endonasal transpterygoid approach to the lateral recess of the sphenoid sinus for repair of temporal lobe encephaloceles, including an overview of the surgical anatomy from an endoscopic perspective, and describe the technical operative nuances and surgical pearls for these cases.

The authors also present 4 new cases of lateral sphenoid recess encephaloceles that were successfully treated using this approach.

Acta Neurochir (2012) 154:621–626. DOI 10.1007/s00701-011-1266-0

Recent advances in minimally invasive surgery have allowed extended transsphenoidal approaches to treat large and complex lesions beyond the sella turcica including basal meningiomas, but the inclusion criteria and limitations of this approach remain unclear.

Methods Retrospective review of 19 consecutive patients (5 males and 14 females aged from 43 to 79 years) with tuberculum sellae meningioma with a maximum diameter of less than 30 mm surgically treated between December 2006 and August 2011 by a single surgeon. Operative outcomes and limitation-based indications were investigated. Findings Total removal was achieved in 15 cases including Simpson’s grade 1 in 2 cases (78.9%). All tumor remnants were located in the lateral portion of the internal carotid artery (ICA), as indicated by preoperative magnetic resonance (MR) imaging. Additional oblique imaging along the longitudinal axis of the C1-2 portion of the ICA revealed a paradoxical presence of tumor in between both sides of the ICA in some patients, even in the case with lateral extension over the ICA on coronal MR imaging. Total removal could be achieved in these patients, and after the introduction of additional preoperative oblique MR imaging, total removal was achieved in all patients. Visual outcomes of eyes showed improvement in 23, remained steady in 11, and showed deterioration in 4, and 89.5% eyes recovered to a good state. Deterioration was caused by injury of a small vein in one patient and previous disruption of the arachnoidal sheath in the remaining three. One patient suffered cerebrospinal fluid leakage and required re-operation. None of the patients developed endocrinological deficits or required prolonged hormonal supplementation.

Conclusions The extended transsphenoidal approach has equivalent potential to transcranial surgery for tuberculum sellae meningiomas with a maximum diameter of less than 30 mm. The tumors with lateral extension over the ICA have fewer chances of total removal. ICA-oriented simulation and surgical planning are important.

Neurosurg Rev (2012) 35:185–194. DOI 10.1007/s10143-011-0346-1

Jugular foramen paragangliomas are rare skull base tumours posing multiple complex diagnostic and management problems. We did a study to evaluate surgical technique, outcome and complications in 75 cases of tumours treated by multidisciplinary approach (i.e. combined neurosurgery, neuroradiology, ear, nose and throat surgery and intensive care unit team).
Methods: Retrospective study on 75 consecutive patients with jugular foramen paragangliomas treated surgically from 1989 to 2005. Preoperative balloon occlusion test was performed in all patients as well as embolization (100%). A combined limited infratemporal and juxtacondylar approach was used in all patients.
Results: Gross total resection was achieved in 59 patients (78.7%). The most common complication was represented by lower cranial nerve deficits in five patients (6.6%), which was only temporary in three. Postoperative facial nerve weakness occurred in five cases (6.6%) and resolved in three of them. The remaining two patients underwent facial nerve reconstruction by hypoglossal/facial nerve anastomosis. Four patients (5.3%) had a postoperative cerebrospinal fluid leak, which was successfully treated by lumbar drainage. Two patients (2.7%) died because of complications related to surgical injury of lower cranial nerves: one patient developed aspiration pneumonia and septicemia and the second one developed a large cervicobulbar hematoma that led to severe respiratory distress and ultimately global cerebral hypoxia.
Conclusion: Paragangliomas are rare and complex skull base lesions that may be managed with low morbidity and mortality if a multidisciplinary approach is considered. Facial and lower cranial nerve postoperative deficits can be limited.

Neurosurg Rev (2012) 35:147–154. DOI 10.1007/s10143-011-0360-3

The cavernous sinus (CS) has one of the most complex anatomical networks of the skull base and because of the diversity of its contents is involved in many pathological processes. Nevertheless, anatomical literature concerning the CS is still controversial, so a systematic literature review was performed to find out the microanatomy of the medial wall of the CS and its clinical importance on sellar pathologies.

Experimental studies from English-language literature between 1996 and 2010 were identified in MEDLINE, LILACS, and Cochrane databases. After analysis, two tables were prepared exhibiting the major points of each article. Fourteen experimental studies were included in the tables.

Four studies concluded that the medial wall of the CS is composed of a loose, fibrous structure, and the remaining ten presumed that the medial wall is formed by a dural layer that constitutes the lateral wall of the sella. The lack of definition standards and of methodological criteria led to variation in the results among different studies.

Thus, this hindered results comparison, possibly explaining the different observations.

Neurosurgery 70[ONS Suppl 1]:ons132–ons144, 2012 DOI: 10.1227/NEU.0b013e31822efb21

Trigeminal schwannomas make up 0.8% to 8% of all intracranial schwannomas.

OBJECTIVE: To analyze our surgical experience with trigeminal schwannomas.

METHODS: We performed 107 operations on 105 patients harboring trigeminal schwannomas over the past 30 years. We classified the tumors as peripheral, ganglion cavernous, posterior fossa root, and dumbbell types according to the portion of the nerve that gave rise to the tumor.

RESULTS: Fourteen were peripheral-type tumors (13.1%), 39 (36.4%) were ganglion cavernous type, 22 (20.6%) were posterior fossa root type, and 32 (30.0%) were dumbbell type. Sixty-five tumors were solid, 35 were mixed, and only 7 were cystic. Among solid tumors, 14 were vascular, fibrous, and adherent to adjacent structures. Total or near-total removal was performed in 86 cases (81.9%), and subtotal removal was achieved in 18 (17.1%). The most common symptom was facial hypesthesia, occurring in 69 patients. This symptom improved in 11 patients, persisted in 50 patients, and worsened in 8 patients after surgery. New postoperative hypesthesia was observed in 8 patients. The second most common symptom was facial pain, observed in 24 patients. Facial pain subsided in 22 and persisted in 2 patients after surgery. Diplopia was observed in 21 patients. This symptom improved postoperatively in 14 patients, persisted in 6 patients, and worsened in 1 patient.

CONCLUSION: The present series demonstrates acceptable results using microsurgical treatment to remove trigeminal schwannomas. Pain and diplopia may be relieved after surgery; however, hypesthesia frequently remains or may be worsened by surgery.

J Neurosurg 116:373–384, 2012. DOI: 10.3171/2011.6.JNS081451

The authors report surgical and endocrinological results of a series of 73 cases of craniopharyngioma that they treated surgically since 1997 to demonstrate their change in treatment strategy and its effect on outcome compared with a previous series and results reported in the literature.

Methods. A total of 73 patients underwent surgery for craniopharyngiomas between May 1997 and January 2005. In patients with poor clinical or neuropsychological condition, even following pretreatment, only stereotactic cyst aspiration took place (8 cases). In the remaining patients, gross-total resection (GTR) was intended and appeared to be possible. The most frequent approaches were subfrontal (27 cases) and transsphenoidal (26 cases); in some cases, a multistep approach was used. The rate of GTR, complications, and functional outcome (comparing pre- and postoperative endocrine and neuropsychological testing) were evaluated. The mean duration of follow-up was 25.2 months.

Results. Gross-total resection was achieved in 88.5% of cases in which a transsphenoidal approach was used and 79.5% of those in which a transcranial approach was used (85.2% of those in which a subfrontal approach was used and 72.7% of those in which a frontolateral approach was used). In the total series, GTR was achieved in 83.1% of cases (vs 49.3% in the authors’ former series). The complication rate was 13.8% without any mortality. New endocrine deficits were observed more frequently in patients treated with transcranial approaches over the years (16.3%– 66.7% vs 2.6%–50.0%) but were less frequent after transsphenoidal approaches (5.2%–19.2% vs 2.9%–45.7%).

Conclusions. Open surgery with intended total resection remains the treatment of choice in most patients. Initial stereotactic cyst aspiration or medical pretreatment to improve the patients’ condition and adequate choice of surgical approach(es) are essential to achieve that goal. Nevertheless, a moderate increase in endocrinological deficits has to be accepted. The authors recommend using radiotherapy only in cases in which there are tumor remnants or disease progression after surgery.