Surgical management of tuberculum sellae meningiomas: involvement of the optic canal and visual outcome

Optic Canal Decompression: Comparison of 2 Surgical Techniques

BACKGROUND

The optic canal is a bony channel that connects the anterior cranial fossa and orbit and contains the optic nerve and ophthalmic artery. It can be affected by several pathologies, leading to compression of the nerve nearby or inside the canal, leading to visual impairment. The usual technique to decompress the canal is through a craniotomy, but recently endoscopic endonasal approaches (EEAs) have surfaced as an interesting alternative due to direct access to the canal without the need for manipulation of neurovascular structures.

METHODS

Six specimens were dissected. The right optic canal was drilled on the right side via the EEA, and the left optic canal was drilled via frontotemporal craniotomy. The amount of decompression was measured using a 3-dimensional reconstruction on computed tomography scans and compared.

RESULTS

The EEA generated an average of 267.8 (221-294) degrees of decompression in the anterior portion of the canal versus 258.3 (219-300) degrees of decompression in the posterior portion of the canal, whereas the craniotomy generated an average of 229.3 (101-289) degrees of decompression in the anterior portion of the canal versus 250.3 (76-300) degrees of decompression in the posterior portion of the canal. There was no significant difference statistically.

CONCLUSION

The decision for an approach for optic canal decompression should be based on the site of the pathology and localization of canal involvement. Both techniques are equivalent in terms of proportion of nerve decompression.

Endoscopic Assisted Supraorbital Keyhole Approach or Endoscopic Endonasal Approach in Cases of Tuberculum Sellae Meningioma: Which Surgical Route Should Be Favored?

OBJECTIVE

Keyhole approaches are under investigation for skull base tumor surgery. They are expected to have a low complication rate with the same successful resection rate compared with endoscopic endonasal procedures. In this study, we compare our current series of tuberculum sellae meningiomas resected via an endoscopic endonasal or microsurgical supraorbital keyhole approach.

METHODS

Between 2011 and 2016, 16 patients were treated using the supraorbital keyhole procedure and 6 patients received an endoscopic endonasal procedure. Both surgical techniques were analyzed and compared concerning complications, surgical radicality, endocrinologic, and ophthalmologic outcome and recurrences in patients' follow-up.

RESULTS

The 2 different approaches yielded similar rates of gross total resection (endonasal 83% [5 of 6] vs. supraorbital 87% [14 of 16]), near total resection (17% [1 of 6] vs. 13% [2 of 16]), and visual recovery (endonasal 66% [2 of 3] vs. supraorbital 60% [3 of 5]). An extension lateral to the internal carotid artery was noted in 81% (13 of 16) of the supraorbital cases and in none of the endonasal cases. Tumor volume was 14.9 cm³ (±8.2 cm³) for supraorbital tumors versus 2.1 cm³ (±0.8 cm³) for the endonasal approach.

CONCLUSIONS

Both approaches provide minimally invasive surgical routes accessing meningiomas of the sellar region. The ideal approach should be tailored to the individual patient considering the tumor anatomy, lateral extension, and the experience of the surgeon with both surgical approaches. We suggest using the supraorbital approach for larger meningiomas of sellar region with far lateral extension or broad vascular encasement.

Craniotomy for perisellar meningiomas: comparison of simple (appropriate for endoscopic approach) versus complex anatomy and surgical outcomes

OBJECTIVE

Microsurgical resection of perisellar meningiomas has remained the gold standard for treatment, with extended endoscopic endonasal surgery emerging as a viable alternative. Historical microsurgical series do not distinguish based on tumor anatomy, but are being used as a comparison against endonasal surgery. In this study, the authors retrospectively reviewed and compared the anatomy of perisellar meningiomas seen at their institution. The tumors were separated into 2 groups based on whether they would be appropriate for endoscopic resection, and the authors compared the surgical outcomes.

METHODS

Between 2001 and 2013, 53 patients (73.6% women) with perisellar meningiomas underwent open microsurgical resection at Vancouver General Hospital performed by the senior author (R.A.). These tumors were separated into 2 groups based on their anatomy, and the authors analyzed the resection rates, surgical results, patient quality of life, and complications.

RESULTS

Among the 53 patients who presented with perisellar meningiomas, the authors were able to identify 18 lesions with “simple” anatomy suitable for endoscopic resection and 35 lesions with “complex” anatomy suitable for craniotomy resection. The mean age of patients in the study cohort was 57.4 years (range 33–91 years), and most patients presented with visual loss (68.0%) and visual field restriction (64.2%). There were no major differences in patient demographic data between the 2 groups. Patients with simple anatomy had smaller lesions (2.1 vs 3.5 cm; p = 0.004), no optic canal invasion (89% vs 26%; p < 0.0001), minimal vascular encasement (cortical cuff 83% vs 9%; p < 0.0001), and a rounded tumor shape (100% vs 31.8%; p = 0.0001) when compared with those with complex anatomy. The majority of lesions originated from the tuberculum sellae and planum sphenoidale. A greater degree of resection was achieved in the favorable anatomy group (99% vs 87.1%; p < 0.0001). Vision was improved or normalized in 96.6% of patients. Patients in the cohort with complex anatomy had more transient complications; there were no incidents of surgical-site infection, meningitis, or death in this series. One patient who underwent removal of a recurrent lesion experienced a CSF leak that required endoscopic repair. The overall persisting complications rate was higher in the group with complex anatomy (11.1% vs 37.1%; p = 0.0498); overall, 28.3% of patients experienced disabling complications. Patient-perceived quality of life improved in the simple anatomy group following surgery (ΔSF-36 +16.6 vs −8.4; p = 0.0045).

CONCLUSIONS

Extended endoscopic surgery is emerging as a viable alternative to microsurgical resection of perisellar meningiomas. The authors identified 2 patient groups based on tumor anatomy, with distinctly separate surgical outcomes. In the future, patients considered for endoscopic resection should be compared against the surgical group with simple anatomy that includes smaller tumors, no vascular encasement, and limited optic canal invasion.

Sellar and Parasellar Imaging

The skull base is a complex anatomical region that harbors many important neurovascular structures in a relatively confined space. The pathology that can develop at this site is varied, and many disease processes may present with similar clinical and neuroimaging findings. While computed tomography maintains a role in the evaluation of many entities and can, for instance, delineate osseous erosion with great detail and characterize calcified tumor matrices, magnetic resonance imaging (MRI) is the mainstay in the neuroimaging assessment of most pathology occurring at the skull base. Various MRI sequences have proven to be robust tools for tissue characterization and can provide information on the presence of lipids, paramagnetic and diamagnetic elements, and tumor cellularity, among others. In addition, currently available MRI techniques are able to generate high spatial resolution images that allow visualization of cranial nerves and their involvement by adjacent pathology. The information obtained from such examinations may aid in the distinction of these disease processes and in the accurate delineation of their extent prior to biopsy or treatment planning.

Penetration and Splitting of Optic Nerve by Tuberculum Sellae Meningioma

Preservation of the optic nerves is an important issue in the resection of tuberculum sellae meningiomas. We report the case of a patient whose optic nerve was penetrated by a tuberculum sellae meningioma. During surgery, a bulging tumor was found to penetrate the right optic nerve. The tumor was gross totally removed, including tumors bulging through the optic nerve. Two trunks of the split optic nerve were preserved. The penetrated shape of the optic nerve may lead to misjudgment and its damage. Divided trunks of optic nerves are difficult to recognize and may be confused for the tumor capsule, because they may be thinned and seem to contain tumors. In addition, a single trunk may be confused for the whole nerve; thus, the other trunk may be easily damaged if not dissected cautiously. Treatment strategy according to the remnant visual acuity was suggested.

Radiosurgical decompression for benign perioptic tumors causing compressive cranial neuropathies: a feasible alternative to microsurgery?

Several studies have reported the efficacy and safety of hypofractionated stereotactic radiosurgery (hSRS) in the treatment of benign perioptic tumors. This study went further and evaluated the feasibility of hSRS in the treatment of those causing compressive cranial neuropathies (CCNs) among perioptic tumors with special consideration of functional improvement. Twenty-six patients with CCNs (CN II = 19; CN III/IV/VI = 9; CN V = 3) caused by perioptic tumors underwent hSRS between 2011 and 2015. hSRS was delivered in five fractions with a median marginal dose of 27.8 Gy (≈14 Gy in a single fraction, assuming an α/β of three) to a tumor volume of 8.2 ± 8.3 cm³. All tumors except one shrank after treatment, with a mean volume decrease of 35 % (range 4-84 %) during the mean follow-up period of 20 months. In 19 patients (38 eyes) with compressive optic neuropathy, vision improved in 55.3 % of eyes (n = 21), was unchanged in 36.8 % (n = 14), and worsened in 7.9 % (n = 3) (2.6 % after excluding two eyes deteriorated due to transient tumor swelling). A higher conformity index (p = 0.034) and volume of the optic apparatus receiving >23.0 Gy (p = 0.019) were associated with greater tumor shrinkage. A greater decrease in tumor volume (p = 0.035) was associated with a better improvement in vision. Ophthalmoplegia and facial hypesthesia improved in six of nine (66.7 %) and three of three (100 %) patients, respectively. There was no newly developed neurological deficit. Decompressive SRS for benign perioptic tumors causing CCN is feasible using hypofractionation, representing a useful alternative to microsurgical resection.

Endoscopic transnasal surgery for planum and tuberculum sella meningiomas: decision-making, technique and outcomes

Tuberculum sella and planum sphenoidale meningiomas pose a management challenge given their intimate relationship to surrounding critical neurovascular structures. The development and advancement of expanded endoscopic transnasal surgery has provided a good surgical option that in well-selected cases, may provide several advantages over a transcranial route. These include early devascularization, complete dura and bone removal, elimination of brain retraction and enhanced visualization of the optic apparatus perforating vessels. The authors review the endoscopic transnasal approach to these tumors and discuss surgical decision-making and case selection, surgical technique and outcomes. We also discuss the expanding role of stereotactic radiosurgery and fractionated stereotactic radiotherapy for these challenging lesions.

Frontolateral Approach Applied to Sellar Region Lesions: A Retrospective Study in 79 Patients

Background:

Various surgical approaches for the removal of sellar region lesions have previously been described. This study aimed to evaluate the reliability and safety of the frontolateral approach (FLA) to remove sellar region lesions.

Methods:

We presented a retrospective study of 79 patients with sellar region lesions who were admitted and operated by the FLA approach from August 2011 to August 2015 in Department of Neurosurgery of Beijing Tian Tan Hospital. We classified FLA into three types, compared the FLA types to the areas of lesion invasion, and analyzed operation bleeding volume, gross total resection (GTR) rate, visual outcome, and mortality.

Results:

Seventy-nine patients were followed up from 2.9 to 50.3 months with a mean follow-up of 20.5 months. There were 42 cases of meningiomas, 25 cases of craniopharyngiomas, and 12 cases of pituitary adenomas. The mean follow-up Karnofsky Performance Scale was 90.4. GTR was achieved in 75 patients (94.9%). Two patients (2.5%) had tumor recurrence. No patients died perioperatively or during short-term follow-up. Three patients (3.8%) with craniopharyngioma died 10, 12, and 23 months, respectively, after surgery. The operative bleeding volume of this study was no more than that of the other approaches in the sellar region (P = 0.783). In this study, 35 patients (44.3%) had visual improvement after surgery, 38 patients (48.1%) remained unchanged, and three patients’ visual outcome (3.8%) worsened.

Conclusions:

FLA was an effective approach in the treatment of sellar region lesions with good preservation of visual function. FLA classification enabled tailored craniotomies for each patient according to the anatomic site of tumor invasion. This study found that FLA had similar outcomes to other surgical approaches of sellar region lesions.

Improvement of long-term blindness caused by compression from inner-third sphenoid wing meningioma after optic canal decompression: An extremely rare case report

Background:

There has been no previous case report of a patient whose visual acuity improved after long-term blindness caused by tumor invasion into the optic canal.

Case Description:

A 65-year-old Asian woman presented with a 6-month history of blindness caused by a meningioma located on the inner third of the sphenoid ridge. An operation was performed to prevent further tumor invasion into the cavernous sinus and contralateral optic nerve. During surgery, optic canal decompression was performed using an epidural approach. Subtotal removal of the tumor was achieved. Two days after the surgery, her left visual acuity recovered from blindness.

Conclusion:

Normally, long-term blindness caused by optic nerve compression by a brain tumor is regarded as irreversible, and even a surgical excision of the optic nerve is performed in some cases. However, because we experienced a case in which the patient recovered from long-term blindness after optic canal decompression, we believe that this surgical procedure should definitely be considered as an option.

Contralateral supraorbital keyhole approach to medial optic nerve lesions: an anatomoclinical study

OBJECTIVE The authors describe the supraorbital keyhole approach to the contralateral medial optic nerve and tract, both in a series of cadaveric dissections and in 2 patients. They also discuss the indications and contraindications for this procedure. METHODS In 3 cadaver heads, bilateral supraorbital keyhole minicraniotomies were performed to expose the ipsilateral and contralateral optic nerves. The extent of exposure of the medial optic nerve was assessed. In 2 patients, a contralateral supraorbital keyhole approach was used to remove pathology of the contralateral medial optic nerve and tract. RESULTS The supraorbital keyhole craniotomy provided better exposure of the contralateral superomedial nerve than it did of the same portion of the ipsilateral nerve. In both patients gross-total resections of the pathology was achieved. CONCLUSIONS The authors demonstrate the suitability of the contralateral supraorbital keyhole approach for lesions involving the superomedial optic nerve.

Surgical Indications of Exploring Optic Canal and Visual Prognostic Factors in Neurosurgical Treatment of Tuberculum Sellae Meningiomas

Background:

Tuberculum sellae meningiomas (TSMs) present a special symptom because of the adherence and compression to the optic nerve, optic artery, and the chiasm. A significant number of patients with TSMs appear visual deficits. This study aimed to investigate the surgical indications of exploring the optic canal and visual prognostic factors in the neurosurgical treatment of TSMs.

Methods:

Totally 21 patients with TSM, who were operated from September 2007 to August 2011 in the Department of Neurosurgery, Tongren Hospital were enrolled in this study. Results of orbital computed tomography (CT) and magnetic resonance imaging (MRI), visual acuity, Goldmann visual field test, orbital color Doppler flow imaging (CDI) test in these patients were retrospectively analyzed.

Results:

Visual deficit and optic canal involvement (OCI) were detected in all the 21 patients. Fourteen patients had bone proliferation within the area of the optic canal. After the operation, visual outcomes were improved in 13 patients, unchanged in 7 patients, and deteriorated in 1 patient. All the 21 patients performed orbital CDI test preoperatively, the results showed that if the peak systolic velocity (PSV) of central retinal artery (CRA) value was ≤8 cm/s, the visual outcome would be better.

Conclusions:

The surgical indications of exploring optic canal in TSM cases included: (1) The neuroimaging evidences of OCI (CT and/or MRI); (2) PSV of CRA in orbital CDI test was ≤8 cm/s; (3) visual acuity was below 0.1; (4) visual field deficit. The PSV of CRA in CDI test could be a prognostic factor for visual outcomes of TSMs.

Endoscopic Endonasal Approach to the Optic Canal: Anatomic Considerations and Surgical Relevance

BACKGROUND

Increasing use of endoscopic endonasal surgery for suprasellar lesions with extension into the optic canal (OC) has necessitated a better endonasal description of the OC.

OBJECTIVE

To identify the osseous OC transcranially and then investigate its anatomic relationship to the key endonasal intrasphenoidal landmarks. We also aimed to determine and describe the technical nuances for safely opening the falciform ligament and intracanalicular dura (surrounding the optic nerve [ON]) endonasally.

METHODS

Ten fresh human head silicon-injected specimens underwent an endoscopic transtuberculum/transplanum approach followed by 2-piece orbitozygomatic craniotomy to allow identification of 20 OCs. After completing up to 270° of endonasal bony decompression of the OC, a dural incision started at the sella and continued superiorly across the superior intercavernous sinus. Subsequently the dural opening was extended anterolaterally across the dura of the prechiasmatic sulcus, limbus sphenoidale, and planum.

RESULTS

Endonasally, the length of the osseous OC was approximately 6 mm and equivalent to the length of the lateral opticocarotid recess, as measured anteroposteriorly. The ophthalmic artery arose from the supraclinoidal carotid artery at approximately 2.5 mm from the medial osseous OC entrance. Transcranial correlation of the endonasal dural incision confirmed medial detachment of the falciform ligament and exposure of the preforaminal ON.

CONCLUSION

The lateral opticocarotid recess allows distinction of the preforaminal ON, roofed by the falciform ligament from the intracanalicular segment in the osseous OC. This facilitates the preoperative surgical strategy regarding the extent of OC decompression and dural opening. Extensive endonasal decompression of the OC and division of the falciform ligament is feasible.

Anatomical Origin of Tuberculum Sellae Meningioma: Off-Midline Location and Its Clinical Implications

OBJECTIVE

Tuberculum sellae meningiomas (TSM) arise from the dura mater of tuberculum sellae, limbus sphenoidale, and chiasmatic sulcus and cause asymmetric visual disturbances. In this study, we analyzed the laterality of the origin of TSM and discussed its clinical implications on immediate and long-term visual outcomes.

METHODS

Between 1994 and 2013, TSM was diagnosed in 100 patients after microsurgical resection. The medical records, radiologic features, and operative findings were retrospectively reviewed and analyzed in these patients.

RESULTS

Visual disturbances were evident in 95 patients (95%) after neuro-ophthalmologic testing. Among them, 89 patients (89%) showed marked asymmetric visual field defect, and 6 patients (6%) had relatively symmetric visual field defect. On intraoperative inspection, the origin of TSM was at the one lateral end portion of the tuberculum sellae in 85 patients (85%). In 15 patients (15%), the TSM originated from the midline region, including the central portion of the tuberculum sellae (n = 13) and diaphragm sellae (n = 2). Optic canal involvement was observed in 73 patients (73%). Preexisting visual field defects were improved in 70 patients (70%), were stationary in 25 patients (25%), and aggravated in 5 patients (5%) during postoperative follow-up (mean 58 months, 24∼122 months). The preoperative symptom duration, the laterality of the origin of TSM, and optic disc atrophy were associated with long-term poor visual outcomes.

CONCLUSIONS

Most TSMs that originated from the dura of one lateral end portion of the tuberculum sellae correlated with asymmetric visual symptoms and poor visual outcomes. This microsurgical feature should be considered in the planning of optimal surgical strategy to achieve favorable outcomes.

Direct visualization of improved optic nerve pial vascular supply following tuberculum meningioma resection: case report

Tuberculum sellae meningiomas frequently produce visual loss by direct compression from tumor, constriction of the optic nerve (ON) under the falciform ligament, and/or ON ischemia. The authors hypothesized that changes in visual function after tumor removal may be related to changes in blood supply to the ON that might be seen in the pial circulation at surgery. Indocyanine green (ICG) angiography was used to attempt to document these changes at surgery. The first patient in whom the technique was used had a left-sided, 1.4-cm, tuberculum meningioma. Time-lapse comparison of images was done postsurgery, and the comparison of video images revealed both faster initial filling and earlier complete filling of the ON pial circulation, suggesting improved pial blood flow after surgical decompression. In follow-up the patient had significant improvements in both visual acuity and visual fields function. Intraoperative ICG angiography of the ON can demonstrate measurable changes in pial vascular flow that may be predictive of postoperative visual outcome. The predictive value of this technique during neurosurgical procedures around the optic apparatus warrants further investigation in a larger cohort.

Frontobasal Midline Meningiomas: Is It Right To Shed Doubt on the Transcranial Approaches? Updates and Review of the Literature

BACKGROUND

Traditionally, the surgical removal of tuberculum sellae meningioma (TSM) and olfactory groove meningioma (OGM) requires transcranial approaches and microsurgical techniques, but in the last decade endoscopic expanded endonasal approaches have been introduced: transcribriform for OGMs and transtuberculum-transplanum for TSM. A comparative analysis of the literature concerning the two types of surgical treatment of OGMs and TSM is, however, difficult.

METHODS

We conducted a literature search using the PubMed database to compare data for endoscopic and microsurgical techniques in the literature. We also conducted a retrospective analysis of selected cases from our series presenting favorable characteristics for an endoscopic approach, based on the criteria of operability of these lesions as generally accepted in the literature, and we compared the results obtained in these patients with those in the endoscopic literature.

RESULTS

We believe that making the sample more homogeneous, the difference between microsurgical technique and endoscopic technique is no longer so striking. A greater radical removal rate, a reduced incidence of cerebrospinal fluid fistula and, especially, the possibility of removing lesions of any size are advantages of transcranial surgery; a higher percentage of improvement in visual outcome and a lower risk of a worsening of a pre-existing deficit or onset of a new deficit are advantages of the endoscopic technique.

CONCLUSION

At present, the microsurgical technique is still the gold standard for the removal of the anterior cranial fossa meningiomas of all sizes, and the endoscopic technique remains a second option in certain cases.

Multi-size, Multi-angle Microbipolar Forceps for Skull Base Surgery: Technical Note

Objective Hemorrhage control in skull base surgery is critical but hindered by the lack of instruments suitable for coagulating structural curves and corners. The main impediment is that most of the instruments currently used are right-angled and unsuitable because anatomical and pathologic structures are three-dimensional objects having complex curves and corners. In this article, we present a solution: the use of angled bipolar microforceps having a range of small diameters and angles for dissection and coagulation.

Methods Utilizing modern design software and up-to-date synthetic and metallic materials, a variety of nonstick bipolar microforceps with different angles and very fine tips (0.2–1.2 mm) were designed and constructed for use on different anatomical and pathologic curves. The tips of the forceps were made very fine to improve coagulation precision as well as to improve microdissection dexterity. The blades were made long and thin to improve visibility during coagulation and dissection procedures. As a result, these multi-size, multiangle micro instruments can be used not only for coagulation but also for microdissection or tumor removal in most anatomical areas accessed during the course of skull base surgery

Results The research, design, and construction of a new bipolar microforceps with different angles and sizes represents a technical innovation that can lead to improved surgical outcomes.

Conclusion The new micro-instruments enhance the quality and quantity of tumor and tissue resection and dissection in skull base surgery and open the possibility of new surgical approaches to microscopic tumor resection and hemorrhage coagulation in the anatomical areas of the skull base.

Open Transcranial Resection of Small (<35 mm) Meningiomas of the Anterior Midline Skull Base in Current Microsurgical Practice

OBJECTIVE

Despite technical surgical advance, the ultimate management of midline anterior skull base meningiomas remains to be defined. Open transcranial surgery is usually the first treatment option for large meningiomas, while less invasive techniques such as endoscopic surgery or radiosurgery might represent an alternative to open microsurgery for smaller lesions. The aim of our study is to investigate the outcome of open transcranial microsurgery in the resection of small (<35 mm) meningiomas of the midline anterior cranial base.

METHODS

Clinical and surgical data from 43 patients affected by small midline anterior skull base meningiomas operated via an open transcranial approach were retrospectively reviewed.

RESULTS

The tumor diameter on its major axis ranged from 12 to 35 mm, with a mean diameter of 28 mm. Gross total resection (Simpson grades I-II) was achieved in 100% of cases through a pterional approach. Postoperative overall morbidity was 9%. It was 3% among patients <70 years. No mortality was reported. Postoperative visual outcome was significantly associated with preoperative visual performance (P = 0.02), but not with preoperative optic nerve compression as detected by magnetic resonance imaging (P = 0.116). Age >70 years was associated with postoperative visual impairment, although not significantly (P = 0.06). Visual function was preserved or improved in 95% of cases, in 100% of patients <70 years, and in 71% of patients with preoperative visual impairment.

CONCLUSIONS

In our experience, open transcranial surgery proved safe and effective for midline anterior skull base meningiomas smaller than 35 mm in all patients <70 years and in patients >70 years without preoperative visual deficit. Our data are consistent with the literature. Conversely, the standard of treatment for the subgroup of patients >70 years with preoperative visual deficit has not yet been defined. This specific subgroup of patients offers a topic for further investigation.

The Pterional Port in Dual-Port Endoscopy: A 2D and 3D Cadaveric Study

Objective We propose a novel dual-port endonasal and pterional endoscopic approach targeting midline lesions of the anterior cranial fossa with lateral extension beyond the optic nerve. Methods Ten dual-port approaches were performed on five cadaveric heads. All specimens underwent an endoscopic transtuberculum/transplanum approach followed by placement of a pterional port. The endonasal port was combined with an endoscopic extradural pterional keyhole craniectomy. The pterional port was placed at the intersection of the sphenoparietal and coronal sutures. The extradural space was explored using two-dimensional and three-dimensional endoscopes. Results The superolateral access provided by the pterional port may improve the ability to achieve a gross total resection of tumors with lateral extensions. The complete opening of the optic canal achieved through the dual-port approach may enable resection of the intracanalicular portion of a tumor, a crucial step in improvement of visual function and reduction of tumor recurrence. Conclusion The pterional port may enhance control of midline anterior skull base lesions with lateral extension beyond the optic nerve and optic canal. Dual-port endoscopy maintains minimally invasiveness and dramatically increases the working limits and control of anatomical structures well beyond what is attainable through single-port neuroendoscopy.

Endoscopic endonasal surgery for suprasellar meningiomas: experience with 75 patients

OBJECT

Following the introduction of the neurosurgical microscope, the outcomes in suprasellar meningioma surgery were dramatically improved. More recently, the neurosurgical endoscope has been introduced as a visualization option during removal of skull base tumors, both transcranially and endonasally. The authors retrospectively reviewed the effectiveness of endoscopic endonasal surgery (EES) in the management of suprasellar meningiomas.

METHODS

Between 2002 and 2011, 75 patients (81.3% female) with suprasellar meningiomas underwent EES at the University of Pittsburgh Medical Center. The authors present the results of EES and analyze the resection rates, visual outcome, and complications.

RESULTS

Seventy-one patients presented with primary tumors, whereas 4 were previously treated elsewhere. Their mean age was 57.3 years (range 36-88 years), and most patients presented with visual loss (81.3%). Tumors occupied the tuberculum sellae (86.7%) and planum sphenoidale (50.7%), with extension into the optic canals in 26.7% (unilateral in 21.3% and bilateral in 5.3%) and the pituitary fossa (9.3%). Gross-total tumor resection (Simpson Grade I) was achieved in 76% of the cases in the whole cohort and in 81.4% of the patients in whom it was the goal of surgery. Tumor location and extension into the optic canals was not a limitation for total resection. Tumor size, configuration, and vascular encasement were significant factors that influenced the degree of resection (p < 0.0001). Vision was improved or normalized in 85.7% of the cases. Visual deterioration following EES occurred in 2 patients (3.6%). Complications included postoperative CSF leaks (25.3% overall, 16.1% in recent years) resulting in meningitis in 4 cases. One patient had an intraoperative injury of the artery of Heubner resulting in associated neurological deficit. Another elderly patient died within 1 month after EES due to cerebral vasospasm and multisystem impairment. No patient developed postoperative cerebral contusions, hemorrhage, or seizures. During a mean follow-up period of 29 months (range 1-98 months), 4 patients have shown recurrence, but only 1 required repeat EES.

CONCLUSIONS

With the goal of gross-total tumor resection and visual improvement, EES can achieve very good results, (comparable to microscopic approaches) for the treatment of suprasellar meningiomas. Avoidance of brain and optic nerve retraction, preservation of the vascularization of the optic apparatus, and wide decompression of the optic canals are the main advantages of EES for the treatment of suprasellar meningiomas, while CSF leaks remain a disadvantage.

Relationship between the pituitary stalk angle in prefixed, normal, and postfixed optic chiasmata: an anatomic study with microsurgical application

BACKGROUND

The relationship between the optic apparatus and the skull base is important during approaches near the sella turcica. One relationship that dictates which approach is taken is whether the optic chiasm is prefixed or postfixed or in a "normal" location, (centered over the diaphragma sella). The relationship between the position of the chiasm and the angulation of the pituitary stalk has not been investigated.

METHODS

Forty adult cadavers without intracranial pathology were dissected and parasagitally hemisected lateral to the sella turcica. The angulations between the pre- and postfixed and normal chiasm and the pituitary stalk were evaluated under magnification. Additionally, 50 MRIs performed among patients evaluating headache were analyzed for these relationships.

RESULTS

For cadavers, the chiasm was prefixed in 7.5% (n = 3), normal in 85% (n = 34), and postfixed in 7.5% (n = 3). On imaging, the chiasm was prefixed in 4% (n = 2), normal in 88% (n = 44), and postfixed in 8 % (n = 4). For all, the relation between the type of chiasm and the pituitary stalk was more often (p < 0.05) 90° or greater for prefixed chiasmata and acute angles for normal or postfixed chiasmata.

CONCLUSIONS

These data may assist skull base surgeons when approaching pathology near the optic chiasm and pituitary stalk.

Impact of anterior clinoidectomy on visual function after resection of meningiomas in and around the optic canal

BACKGROUND

Meningiomas of the anterior and middle skull base frequently involve the optic nerve and cause progressive visual impairment. Surgical decompression of the optic nerve is the only option to preserve visual function. Depending on the invaded structures, optic nerve decompression can be part of a complete tumor removal or the main surgical intention in terms of local debulking. However, bony decompression of the optic canal including anterior clinoidectomy for optic nerve decompression is still a surgical maneuver under discussion.

METHODS

From 2006 to 2011, 46 consecutive patients with skull base meningiomas in and around the optic canal were operated. The pterional approach was tailored for each patient. Resection included bony decompression of the optic canal with or without anterior clinoidectomy. Visual acuity and fields were evaluated pre- and postoperatively.

RESULTS

Fifty-three percent of patients underwent anterior clinoidectomy, 23 % optic canal unroofing, and 24 % any bony decompression. In 21 patients (46 %), gross total resection (GTR, Simpson grade I or II) was achieved, while 25 patients (54 %) received subtotal resection (STR, Simpson grade III or IV). Sixty-three percent of patients presented with preoperative visual impairment. Postoperative visual changes were significantly related to preoperative visual function. While all patients with normal preoperative vision remained unchanged, in patients with impaired vision, surgery caused improvement in 70 % and deterioration in 10 % of patients (p < 0.0001). In patients with anterior clinoidectomy, vision improved more frequently than without anterior clinoidectomy (p < 0.05).

CONCLUSIONS

Anterior clinoidectomy is safe and may improve visual outcome in meningiomas in and around the optic canal.

Endoscopic resection of tuberculum sellae meningiomas

Objective To evaluate the results of endoscopic transnasal resection of tuberculum sellae meningiomas (TSMs) as compared with transcranial approaches. Design We retrospectively analyzed five patients who underwent endoscopic endonasal resection of TSM and performed a comprehensive review of articles published between 2000 and 2012 describing the operative treatment of TSMs. Results Gross total resection (GTR) was achieved in four patients (80%). Transient diabetes insipidus occurred in three patients (60%). Preoperative visual field deficit resolved in all patients. Cerebrospinal fluid (CSF) leak occurred in one patient. Analysis of published studies included 1,026 transcranial and 144 transnasal cases. GTR was achieved in 85% of transcranial and 72% of transnasal cases. Visual field deficit improved in 65% of transcranial and 82% of transnasal cases. Rate of diabetes insipidus and CSF leak was higher in the transnasal series. Rate of GTR and visual improvement was higher in endoscopic endonasal as compared with microsurgical transnasal series. Conclusion The literature supports transsphenoidal surgery for the resection of TSMs with significant optic nerve compromise and limited lateral extension. This approach may have an equivalent if not superior outcome over transcranial surgery in visual outcome. CSF leaks are still a challenge but may improve with the use of vascularized nasoseptal flaps.

Tuberculum sellae meningiomas: surgical technique, visual outcome, and prognostic factors in 51 cases

Complete tumor resection with preservation or improvement of visual function is the goal of tuberculum sellae meningioma (TSM) treatment. The authors retrospectively reviewed 51 patients treated surgically for TSM between 2003 and 2010, with special attention to surgical technique, visual outcomes, and prognostic factors for treatment outcome. All patients were operated via the lateral subfrontal approach. The cohort mean age and Karnofsky performance status (KPS) on admission was 57.1 ± 13.6 and 84.3 ± 11.7, respectively. The most common presenting sign was visual impairment. The mean tumor size was 29.4 ± 10.7 mm. In 45 of the patients (88.2%), gross total resection was achieved. Improvement and/or preservation of visual acuity and visual field were achieved in 95.9% and 85.3%, respectively. Visual functions on admission were found to be the strongest predictors for postoperative improvement in visual outcome, followed by better KPS on admission, smaller tumor size, and young age. Postoperative neurological complications included cerebrospinal fluid (CSF) leak, meningitis, and postoperative seizures. TSM can be safely operated on through the lateral subfrontal approach. A high percentage of complete tumor resection and excellent visual outcomes are achieved using this technique. Surgical treatment in the early stage of the disease may result in a better visual outcome.

Clinical outcomes of tuberculum sellae meningiomas focusing on reversibility of postoperative visual function

BACKGROUND

Tuberculum sellae meningiomas present a special challenge because of their proximity to major arteries, visual pathways, and the hypothalamus. The aim of this study was to determine the prognostic determinants of clinical and visual outcomes of these tumors, focusing on the functional reversibility of an unserviceable eye after surgery.

METHODS

We retrospectively reviewed 86 patients on the basis of clinical and radiological factors that appeared to affect outcome. The visual acuity and visual fields were analyzed according to the visual impairment score (VIS). Unserviceable visual acuity included no perception of light (NPL), hand movement (HM), and counting fingers (CF). Ophthalmological functioning was tested in the preoperative period, the postoperative short-term period (≤2 weeks after surgery), and the postoperative long-term period (>6 months after surgery). Our own clinical outcome criteria including tumor control, visual improvement, and complications were used for evaluation.

RESULTS

Seventy-four of 86 patients (86 %) underwent total removal of the tumor. In three of these cases (3.4 %), recurrence developed. Thirty patients were classified into the "Excellent" group, 21 into the "Good" group, 20 into the "Fair" group, and 15 into the "Poor" group. In multivariate analysis, adhesion to optic nerve was an independent and significant predictor of clinical outcome. Favorable visual outcomes in both short- and long-term postoperative periods were achieved in 80.8 % of cases. Preoperative and short-term visual outcomes were closely related to long-term visual outcome. Six of eight patients with preoperative CF status showed reversibility to a serviceable status after surgery. However, there was no conversion to serviceable status from NPL or HM.

CONCLUSIONS

For patients with unilateral unserviceable visual function, maintenance of serviceable visual function on the opposite side might be more important. Of the patients with unserviceable visual function, careful surgery might be able to improve the visual function in CF eyes.

Surgical unroofing of the optic canal and visual outcome in basal meningiomas

BACKGROUND

To define from a series of surgically treated suprasellar, anterior clinoid, and sphenoid wing meningiomas, an unequivocal criterion for performing optic canal deroofing in patients with basal meningiomas with deteriorated vision.

METHODS

One hundred-fifty consecutive patients with suprasellar and parasellar meningiomas (44 tuberculum sellae, 46 clinoidal, and 60 spheno-orbital) who underwent surgery between 1988 and 2008 are retrospectively analyzed. The rate of preoperative visual deficit, the incidence of optic canal involvement, the related surgical management, and its influence on visual outcome are reviewed in all tumor localizations.

RESULTS

All 44 patients with tuberculum sellae meningiomas had variable preoperative visual impairment. All were operated on by transcranial approach. Unroofing of the optic canal was performed in the two cases with intracanalar tumor extension. Postoperatively, the visual function improved in 27 patients (61.4 %) and was unchanged in 17 (25 %). Among 46 patients with clinoidal meningiomas, visual dysfunction was found in 30 (65.2 %). The first 32 patients were operated on by classical pterional approach, with selective opening of the optic canal in six cases (group A), whereas all the last 14 underwent routine anterior clinoidectomy and opening of the optic canal (group B). The visual function improved postoperatively in 17 among 30 patients (56.7 %), with a significantly higher rate in group B cases (80 % versus 45 %). Among 60 patients with spheno-orbital meningiomas, 36 (60 %) had visual dysfunction and 43 (71.6 %) involvement of the optic canal. The visual function improved in 18 cases (50 %), was unchanged in 13 (36 %), and worsened in 5 (14 %). Lateral tumors had the lowest rate of optic canal involvement and a 100 % rate of visual improvement; on the other hand, all orbital apex and diffuse tumors had concentric invasion of the optic canal with a 18.6 % rate of visual worsening.

CONCLUSIONS

UOC seems to be a safe procedure not associated with immediate postoperative impairment of the vision. We recommend routine deroofing of the optic canal coupled with extradural anterior clinoidectomy in all clinoidal meningiomas in order to obtain early and complete exposure of both intradural and extradural segments of the optic nerve. For tuberculum sellae meningiomas, we advise to open the optic canal only in cases with intracanalar tumor extension. Finally, for spheno-orbital meningiomas, we recommend UOC through a cranio-orbital approach in almost all cases, except for lateral meningiomas, where the involvement of the lateral wall of the optic canal is rare and may be successfully managed through a lateral orbitotomy without craniotomy.

Tuberculum sellae meningiomas: A series of 41 cases; surgical and ophthalmological outcomes with proposal of a new prognostic scoring system

Context:

Tuberculum sellae meningiomas have proved difficult to treat, partly because of their intimate association with the optic nerves and chiasma, hypothalamus, and internal carotid arteries.

Aims:

The aim of this study is to analyze the degree of influence of various prognostic factors affecting visual outcome; the pattern of visual recovery and develop a scoring system for prognostication.

Settings and Design:

This is a retrospective study carried out from January 2004 till June 2011.

Materials and Methods:

Patients were analyzed on the basis of clinical, radiological, and surgical factors that appeared to affect the outcome. A special scoring system (according to the guidelines of the German Ophthalmological Society) was adopted to quantify the extent of ophthalmological disturbances.

Statistical Analysis Used:

Comparison of categorical variables between the two was performed using chi-square test and a P value of ≤ 0.05 was considered significant. Logistic regression was used when multivariate analysis was required.

Results:

Vision improved in 27% and deteriorated in 7.3%. A prognostic scoring system (score 4–13) was developed depending on the degree of influence of significant prognostic factors. The patients with a score of ≤6 had improved vision postoperatively (44%), whereas none of those with a score > 6 improved. Completeness of visual recovery was perceived in 100% of patients within 3 months. Complete resectability was achieved in 73% of patients.

Conclusions:

The proposed scoring system is very useful in prognosticating the visual outcome of these patients. The patients with a score of ≤6 have the best visual outcome postoperatively. Complete resectability is better achieved with extended bifrontal and unilateral frontal approaches. Short-term postoperative visual outcome is a strong indicator of permanent visual outcome after surgery.

Predictive factors for vision recovery after optic nerve decompression for chronic compressive neuropathy: systematic review and meta-analysis

Objectives Surgical optic nerve decompression for chronic compressive neuropathy results in variable success of vision improvement. We sought to determine the effects of various factors using meta-analysis of available literature. Design Systematic review of MEDLINE databases for the period 1990 to 2010. Setting Academic research center. Participants Studies reporting patients with vision loss from chronic compressive neuropathy undergoing surgery. Main outcome measures Vision outcome reported by each study. Odds ratios (ORs) and 95% confidence intervals (CIs) for predictor variables were calculated. Overall odds ratios were then calculated for each factor, adjusting for inter study heterogeneity. Results Seventy-six studies were identified. Factors with a significant odds of improvement were: less severe vision loss (OR 2.31[95% CI = 1.76 to 3.04]), no disc atrophy (OR 2.60 [95% CI = 1.17 to 5.81]), smaller size (OR 1.82 [95% CI = 1.22 to 2.73]), primary tumor resection (not recurrent) (OR 3.08 [95% CI = 1.84 to 5.14]), no cavernous sinus extension (OR 1.88 [95% CI = 1.03 to 3.43]), soft consistency (OR 4.91 [95% CI = 2.27 to 10.63]), presence of arachnoid plane (OR 5.60 [95% CI = 2.08 to 15.07]), and more extensive resection (OR 0.61 [95% CI = 0.4 to 0.93]). Conclusions Ophthalmologic factors and factors directly related to the lesion are most important in determining vision outcome. The decision to perform optic nerve decompression for vision loss should be made based on careful examination of the patient and realistic discussion regarding the probability of improvement.

Endoscopic versus open resection of tuberculum sellae meningiomas: a decision analysis

BACKGROUND/AIMS

Tuberculum sellae meningiomas (TSMs) are challenging tumors for surgical resection. Endoscopic endonasal (EE) approaches to these lesions have not been directly compared to open craniotomy in a controlled trial.

METHODS

We searched Medline and Embase online databases for English-language articles containing key words related to TSMs. Data were pooled, including 5 of our own patients reported here for the first time. Metaregression was used and a decision-analytical model was constructed to compare outcomes between open microsurgery and EE approaches.

RESULTS

The overall quality of life (QOL) was not significantly different between the approaches (p = 0.410); however, there were large differences in individual complication rates. The Monte Carlo simulation yielded an overall average QOL in craniotomy patients of 0.915 and in endoscopic patients of 0.952. Endoscopy had a higher CSF leak rate (26.8 vs. 3.5%, p < 0.001) but a lower rate of injury to the optic apparatus (1.4 vs. 9.2%, p < 0.001) compared with craniotomy. The 3-year recurrence rates were not statistically different (p = 0.529).

CONCLUSION

EE resection of TSMs appears to be a comparable alternative to traditional open microsurgical resection with respect to overall QOL based on available publications. A meaningful comparison of recurrence rates will require a longer follow-up.

Validation of the superior interhemispheric approach for tuberculum sellae meningioma: clinical article

OBJECT

The objective of this study was to evaluate the ophthalmological outcome, nonvisual morbidity, and surgical complications after tuberculum sellae meningioma (TSM) removal using a superior interhemispheric approach.

METHODS

In the last decade, 20 consecutive patients with TSM underwent operations using the superior interhemispheric approach. Visual acuity, visual field, and ocular fundus examination were assessed both preoperatively and 6-months postoperatively. Nonvisual morbidity was determined at an early postoperative period and at 6 months based on assessment of the Karnofsky Performance Scale score, leakage of CSF, endocrinological status, and olfactory function, which was assessed using a visual analog scale (VAS). The potential brain injury related to the approach was assessed by MRI at 6 months. Magnetic resonance imaging was then performed yearly to detect a recurrence. The mean follow up was 56.3 ± 34 months.

RESULTS

The primary presenting symptom for diagnosis of TSM in 20 patients (female:male ratio of 6.6:1, mean age 59.1 ± 11.1 years) was visual disturbance in 12 patients (60%), headache in 4 (20%), cognitive alteration in 1 (5%), epilepsy in 2 (10%), and accidental in 1 (5%). In a total of 40 eyes, 17 eyes in 11 patients presented with preoperative deterioration of visual acuity. Postoperatively, the visual acuity improved in 13 eyes in 8 patients (72.8%), remained unchanged in 3 eyes in 2 patients (18.2%) and deteriorated in 1 patient (9%). The nonvisual morbidity included olfactory deterioration in 7 patients (35%), and panhypopituitarism in 1 patient (5%). No patients experienced a CSF leak. The impact of olfactory deterioration on the quality of life, as estimated by a VAS score (range 0-10), was a mean of 5.7 ± 2.2 (95% CI 4.1-7.3). On the follow-up MRI, no additional lesions or recurrences were observed on the medial aspect of the frontal lobe along the surgical corridor.

CONCLUSIONS

The superior interhemispheric approach appears to be effective in resolving the problem of visual deterioration due to a TSM, without inducing surgical injury on the brain surface along the surgical corridor. Olfactory deterioration remained the challenging predominant nonvisual morbidity using this approach.

Lateral supraorbital approach applied to tuberculum sellae meningiomas: experience with 52 consecutive patients

BACKGROUND

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 post-discharge, 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.

Endoscopic endonasal resection of anterior skull base meningiomas

OBJECTIVE

Anterior cranial fossa (ACF) meningiomas are difficult to surgically manage. Endoscopic transnasal approaches have increasingly been used as a minimally invasive route and thus offer significant advantages. However, a paucity of literature describing the intraoperative challenges and postoperative outcomes of this technique still exists.

STUDY DESIGN

Case series with chart review.

SETTING

The Royal Adelaide Hospital, Flinders Medical Centre, Wellington Hospital.

SUBJECTS AND METHODS

Fifteen consecutive patients who underwent endoscopic resection of ACF meningiomas between 2004 and 2010 by the South Australian and Wellington Skull Base Units. Demographic and clinical information was compiled by reviewing patient charts and operation notes. Safety and efficacy of the procedure, role of a team approach, and areas for further improvement were analyzed.

RESULTS

Of the patients, 87% were women. Tumor locations: 8 olfactory groove, 2 tuberculum sellae, 1 clinoidal, 1 jugum sphenoidale, 1 planum sphenoidale, 1 subfrontal, and 1 midline ACF floor. Commonest presenting symptom was visual change. Mean volume of tumor was 25.69 cm(3), with a size area of 7.28 cm(2). Five were revision cases. None had previous endonasal surgery. Average operating times decreased over time. Gross total removal was achieved in 14, with no deaths. Four patients had postoperative cerebrospinal fluid (CSF) leak. Rate of CSF leak decreased over time. Sixty percent of patients reported visual improvement. Two patients had radiological evidence of recurrence.

CONCLUSION

ACF meningiomas can be safely removed endonasally, offering significant advantages over the traditional transcranial approach for suitable tumors. Early audit of this approach shows results achieved by this unit are comparable with the published literature.

The Importance and Timing of Optic Canal Exploration and Decompression During Endoscopic Endonasal Resection of Tuberculum Sella and Planum Sphenoidale Meningiomas

BACKGROUND:

Suprasellar meningiomas often invade the optic canals (OCs). The feasibility of removing these tumors through a minimal-access endonasal route has been demonstrated, but the importance, safety, and timing of OC exploration and decompression are not well described.

OBJECTIVE:

To create a simple decision-tree algorithm for OC exploration and decompression in the endonasal endoscopic surgery for planum sphenoidale and tuberculum sella meningiomas.

METHODS:

We identified a consecutive series of 8 planum sphenoidale and tuberculum sella meningiomas resected endonasally. “Late” OC exploration and decompression was performed in 4 of 8 patients. The extent of resection, visual outcome, and complications were recorded.

RESULTS:

Five patients had OC invasion on magnetic resonance imaging. Endoscopic inspection did not reveal additional OC invasion. The OC was opened bilaterally in 2 patients and unilaterally in 2 patients. Gross total resection was achieved in 6 of 7 patients in whom it was the goal. Vision improved in 3 patients (3 of 3 OCs opened) and was stable in 4 (1 of 4 OCs opened). In 1 patient, the bitemporal hemianopsia improved, but there was unilateral deterioration (no OC invasion) because the tumor was extremely adherent to 1 optic nerve. After an average follow-up of 20.9 months, all patients had an Glasgow Outcome Scale score of 5, and there were no cerebrospinal fluid leaks.

CONCLUSION:

Exploration and decompression of the OC are feasible, safe, and important to optimize visual outcome and to minimize recurrence in planum sphenoidale and tuberculum sella meningiomas resected endonasally. It may not be important to open the canal early during surgery because tumor debulking can be performed without manipulating the optic nerves. Early decompression, however, is technically feasible.

Endoscopic skull base surgery: a comprehensive comparison with open transcranial approaches

Little data exists comparing endoscopic endonasal approaches to pathology of the anterior skull base with more traditional transcranial and transsphenoidal microscopic approaches. In order to more fully characterize the role of endoscopy in the management of pathology of the anterior cranial base, we conducted a systematic review of case series and case reports documenting surgical and clinical outcomes. We found that for craniopharyngiomas, clival chordomas, esthesioneuroblastomas and giant pituitary adenomas, the endonasal endoscopic approach can result in equivalent or higher rates of gross total resection than open approaches. For meningiomas, however, open transcranial approaches are still able to achieve higher rates of total resection. CSF leak rates are higher for patients undergoing endoscopic surgery for meningiomas and craniopharyngiomas, but not for chordomas, esthesioneuroblastomas or giant pituitary adenomas. In certain patients, the endonasal endoscopic approach may be a safe and effective alternative for the treatment of a wide variety of skull base pathology, particularly those with small midline tumours.

Optic canal decompression with dural sheath release; a combined orbito-cranial approach to preserving sight from tumours invading the optic canal

PURPOSE

The purpose of this case series is to describe an orbito-cranial surgical approach for the management of optic nerve compression secondary to tumours extending into the optic canal.

METHOD

We present a retrospective, observational case series of 4 patients who underwent surgery aimed at improving or stabilising vision for tumours invading the optic canal. In all cases tumours were not amenable to complete resection due to their intrinsic relation to important structures including: the internal carotid artery, cavernous sinus, optic and oculomotor nerves. All patients underwent combined orbito-cranial surgery consisting of craniotomy, debulking of the tumour, transcaruncular orbital and optic canal decompression with release of the dural sheath overlying the optic nerve via the craniotomy approach. Visual acuity was the primary outcome measure.

RESULTS

Four patients, aged 42, 44, 61 and 78 years, three with spheno-orbital meningioma and one with cerebral sino-nasal adenocarcinoma were included in the study. Mean postoperative follow-up time was 26, 19 and 15.6 months. The fourth patient died at 2.9 months post-surgery due to high grade aggressive cerebral adenocarcinoma. Postoperative visual acuity improved by greater than 4 lines of Snellen acuity in 2 patients at 26 and 19.1 months. Two patients decreased from counting fingers vision to perception of light at last follow-up.

CONCLUSIONS

In cases of non-resectable meningioma extending into the optic canal with secondary optic nerve compression, a combined surgical approach with optic canal decompression and dural sheath release may help preserve and even improve vision in certain cases.

Postoperative recovery from unilateral blindness caused by tuberculum sellae meningioma

A 47-year-old female had noticed diminished visual acuity in both eyes 2 months previously. The patient had vision loss (no light perception) in her right eye on admission. Her left visual acuity was 1.2 (naked vision) and an upper temporal quadrant hemianopsia was revealed in her left eye. Optic disc atrophy was also found bilaterally during a fundus examination. The tumor was located at the tuberculum sella. The first operation was performed using a right pterional approach. The right optic nerve was thin and atrophic and was severely encased by the tumor. Considering the deterioration of her visual evoked potential, the operation was terminated in the remaining major part of the tumor. Postoperatively, the patient suffered visual loss in her right eye (no light perception), decreased visual acuity (naked: 0.6 (corrected: 1.0)), and deteriorated visual field defects (upper temporal quadrant hemianopsia) in her left eye. The tumor remnant was resected again 2 weeks later using the right frontobasal and pterional approaches. The tumor around the bilateral internal carotid arteries and optic nerves was not resected. Light perception in the right eye appeared 2 weeks after the operation. Although an opthalmological examination revealed right optic atrophy, finger counting was possible in the upper nasal visual field of the right eye three months after the second operation. Her visual acuity was 0.7 (1.0), and the upper temporal quadrant hemianopia of the left eye improved in comparison with the preoperative one. Our case demonstrated the possibility of a recovery from blindness.

Pterional approach versus unilateral frontal approach on tuberculum sellae meningioma: Single centre experiences

INTRODUCTION

Tuberculum Sellae Meningioma is one of the most challenging surgeries among neurosurgeons. Many approaches have been established in the effort of removing the tumor and some of them are supported by an advanced neurosurgical technology. In this study, we aim to compare the efficacy of the two most common approaches, the pterional and the unilateral frontal.

MATERIALS AND METHODS

This was a restrospective study that aimed to observe the efficacy of the two most common approaches used in our center, the pterional and the unilateral frontal, in resecting the tuberculum sellae meningioma, which was held in Dr. Hasan Sadikin General Hospital, Bandung, from July 2007-July 2010. Twenty patients were enrolled with half of them operated by the pterional approach and the rest by unilateral frontal approach. We evaluated six parameters: tumor size, degree of tumor removal, surgery duration, post-operative cerebral edema, patients' outcome, and length of stay, which were evaluated to take measure of the efficacy of each procedure.

RESULTS

We found that the pterional approach gave more advantages than the unilateral frontal. Total tumor removal, especially in tumor size ≥ 3 cm was achieved in a greater number of subjects in the pterional (P<0.023). Other advantages of the pterional compared to the unilateral frontal were a shorter surgical duration (P=0.024), shorter length of stay (P=0.009) and less frequency of post-operative cerebral edema incidence (P=0.023).

CONCLUSION

According to our facilities and conditions, it seems that the pterional approach have more advantages than the unilateral frontal approach in tuberculum sellae meningioma surgery.

Endoscopic endonasal versus open transcranial resection of anterior midline skull base meningiomas

OBJECTIVE

To assess the advantages and limitations of the endoscopic endonasal approach to anterior skull base meningiomas, a minimally invasive approach that avoids extensive bone drilling, brain retraction, and manipulation of nerves and critical vessels, versus open transcranial surgery.

METHODS

A MEDLINE (2000-2010) search was performed to identify series for either olfactory groove meningiomas or tuberculum sellae (TS) or planum sphenoidale meningiomas. Statistical analyses of categorical variables such as extent of resection, morbidity, and visual outcome were performed using χ(2) and Fisher exact tests.

RESULTS

The literature review included 60 studies, involving 1426 patients. Open surgery achieved a higher rate of gross total resection (GTR) for both olfactory groove (P < 0.001) and TS and planum (P < 0.001) meningiomas. Postoperative cerebrospinal fluid (CSF) leak occurred more frequently in the endoscopic cohort (P < 0.001). Other postoperative complications occurred more frequently in the open cohort, although this difference was not statistically significant. There were no significant differences in postoperative visual outcome between the groups.

CONCLUSIONS

Based on the current literature, open transcranial approaches for olfactory groove and TS and planum sphenoidale meningiomas still result in higher rates of total resection with lower postoperative CSF leak rates. The endoscopic endonasal approach may be safe and effective for certain skull base meningiomas; careful patient selection and multilayer closure techniques are essential.