Supraorbital eyebrow approach to skull base lesions

The classical supraorbital minicraniotomy to approach the areas of origin of anterior skull base meningiomas: Anatomical nuances influencing accessibility, operability, and frontal lobe retraction

Background

The classical supraorbital minicraniotomy (cSOM) constitutes a minimally invasive alternative for the resection of anterior skull base meningiomas (ASBM). Surgical success depends strongly on optimal patient selection and surgery planning, for which a careful assessment of tumor characteristics, approach trajectory, and bony anterior skull base anatomy is required. Still, morphometrical studies searching for relevant anatomical factors with surgical relevance when intending a cSOM for ASBM resection are lacking.

Methods

Bilateral cSOM was done in five formaldehyde-fixed heads toward the areas of origin of ASBM. Morphometrical data with potential relevant surgical implications were analyzed.

Results

The more tangential position of the cSOM with respect to the olfactory groove (OG) led to a reduction in surgical freedom (SF) in this area compared to others (P < 0.0001). Frontal lobe retraction (FLR) was also higher when approaching the OG (P < 0.05). Olfactory nerve mobilization was higher when accessing the planum sphenoidale (PS), tuberculum sellae (TS), and anterior clinoid process (ACP) (P < 0.0001). OG depth and the slope of the sphenoid bone between the PS and TS predicted lower SF and higher frontal retraction requirements along the OG and TS, respectively (P < 0.05). In contrast, longer distances to the ACP tip predicted lower SF over this structure (P < 0.01).

Conclusion

Although clinical validation is still needed, the present anatomical data suggest that assessing minicraniotomy's position/extension, OG depth, the sphenoid's slope, and distance to ACP-tip might be of particular relevance to predict FLR, maneuverability, and accessibility when considering the cSOM for ASBM resection, thus helping surgeons optimize patient selection and surgical strategy.

Cosmetic Outcomes of Supraorbital Keyhole Craniotomy Via Eyebrow Incision: A Systematic Review and Meta-Analysis

Background  Supraorbital eyebrow craniotomy is a minimally invasive alternative to a frontotemporal craniotomy and is often used for tumor and vascular pathologies. The purpose of this study was to investigate how patient cosmetic outcomes are affected by technique variations of this approach. Methods  PubMed, Embase, and Scopus databases were systematically searched, and results were reported according to PRISMA guidelines. For the meta-analysis portion, the DerSimonian-Laird random effects model was used, and the primary end points were patient satisfaction and percentage of permanent cosmetic complications. Results  A total of 2,629 manuscripts were identified. Of those, 124 studies (8,241 surgical cases) met the inclusion criteria. Overall, 93.04 ± 11.93% of patients reported favorable cosmetic outcome following supraorbital craniotomy, and mean number of cases with permanent cosmetic complications was 6.62 ± 12.53%. We found that vascular cases are associated with more favorable cosmetic outcomes than tumor cases ( p  = 0.0001). Addition of orbital osteotomy or use of a drain is associated with adverse cosmetic outcomes ( p  = 0.001 and p  = 0.0001, respectively). The location of incision, size of craniotomy, utilization of an endoscope, method of cranial reconstruction, skin closure, use of antibiotics, and addition of pressure dressing did not significantly impact cosmetic outcomes ( p  > 0.05 for all). Conclusions  Supraorbital craniotomy is a minimally invasive technique associated with generally high favorable cosmetic outcomes. While certain techniques used in supraorbital keyhole approach do not pose significant cosmetic risks, utilization of an orbital osteotomy and the addition of a drain correlate with unfavorable cosmetic outcomes.

The Endoscopic-Assisted Supraorbital Approach for Resection of Anterior Skull Base Meningiomas: A Large Single-Center Retrospective Surgical Study

Objective The endoscopic-assisted supraorbital approach (eSOA) constitutes a minimally invasive strategy for removing anterior skull base meningiomas (ASBM). We present the largest retrospective single-institution and long-term follow-up study of eSOA for ASBM resection, providing further insight regarding indication, surgical considerations, complications, and outcome.

Methods We evaluated data of 176 patients operated on ASBM via the eSOA over 22 years.

Results Sixty-five tuberculum sellae (TS), 36 anterior clinoid (AC), 28 olfactory groove (OG), 27 planum sphenoidale, 11 lesser sphenoid wing, seven optic sheath, and two lateral orbitary roof meningiomas were assessed. Median surgery duration was 3.35 ± 1.42 hours, being significantly longer for OG and AC meningiomas (p <0.05). Complete resection was achieved in 91%. Complications included hyposmia (7.4%), supraorbital hypoesthesia (5.1%), cerebrospinal fluid fistula (5%), orbicularis oculi paresis (2.8%), visual disturbances (2.2%), meningitis (1.7%) and hematoma and wound infection (1.1%). One patient died due to intraoperative carotid injury, other due to pulmonary embolism. Median follow-up was 4.8 years with a tumor recurrence rate of 10.8%. Second surgery was chosen in 12 cases (10 via the previous SOA and two via pterional approach), whereas two patients received radiotherapy and in five patients a wait-and-see strategy was adopted.

Conclusion The eSOA represents an effective option for ASBM resection, enabling high complete resection rates and long-term disease control. Neuroendoscopy is fundamental for improving tumor resection while reducing brain and optic nerve retraction. Potential limitations and prolonged surgical duration may arise from the small craniotomy and reduced maneuverability, especially for large or strongly adherent lesions.

Supraorbital Keyhole Craniotomy via Eyebrow Incision: A Systematic Review and Meta-Analysis

BACKGROUND

Supraorbital eyebrow keyhole craniotomy is a minimally invasive alternative to a frontotemporal craniotomy and is often used for tumor resection and aneurysm clipping. The purpose of this study is to provide a contemporary review on the outcomes related to this approach and to determine whether they vary with the type of pathology and the addition of an endoscope.

METHODS

PubMed, Embase, and Scopus databases were systematically searched, and results were reported according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. For the meta-analysis portion, the DerSimonian-Laird random effects model was used.

RESULTS

A total of 2629 manuscripts were identified. of those, 124 studies (8241 surgical cases) met the inclusion criteria. Mean total complication rate was 26.7 ± 25.7% and the mean approach-related mortality rate was 1.3 ± 2.8%. Technical success, defined as gross total tumor resection or complete aneurysm clipping, was achieved in 83.6 ± 21.5% of the cases. Vascular pathologies were associated with greater technical success, lower total complications, and longer length of hospital stay compared with tumor cases (P < 0.05 for all). For vascular cases, addition of the endoscope yielded lower technical success (P = 0.001) and lower complication rate (P = 0.041). The use of the endoscope for tumor pathologies did not affect technical success, complications, mortality, length of hospital stay, operative time, or reoperation rate (P > 0.05).

CONCLUSIONS

The supraorbital craniotomy via an eyebrow incision is a feasible minimally invasive approach with an overall high technical success rate for both vascular and tumor pathologies.

The Supraorbital Approach via an Eyebrow Incision: Analysis of Cosmetic Outcomes Using the Scar Cosmesis Assessment Rating Scale

ABSTRACT

The supraorbital craniotomy through an eyebrow incision, referred to as the suprabrow approach, may be used to access intracranial lesions. Though offering good surgical exposure for anterior base cranial lesions, the suprabrow approach has a paucity of studies on its cosmetic outcomes. In this study, we aimed to assess the cosmetic outcomes of suprabrow approach using validated Scar Cosmesis Assessment Rating (SCAR) scale for the first time. Three patients underwent a suprabrow approach for resection of a suprasellar or frontal mass. Their postoperative courses were followed, with specific attention to the cosmetic outcome of their procedures. The SCAR scale was used to determine the cosmetic success of the approach. We found that all 3 patients scored ≤ 5 on the SCAR scale. All 3 resections were successful with no major postoperative complications. The only minor complication was transient hypoesthesia of the ipsilateral forehead that was noted in all 3 patients.This study quantified the positive cosmetic outcomes of a minimally invasive suprabrow approach. The suprabrow approach provides acceptable surgical exposure and access in an appropriately selected patient with anterior cranial base lesions and results in favorable cosmesis. Although transient hypoesthesia in the distribution of the ophthalmic branch of the trigeminal nerve occurs, the overall benefits of the approach and desirable cosmetic outcomes make the suprabrow approach a good technique to access intracranial lesions in appropriate cases.

Comparative study between minimally invasive supraorbital craniotomy and pterional craniotomy for treating anterior circulation cerebral aneurysms in a low-resource setting

The challenges encountered in performing minimally invasive approaches, such as supraorbital minicraniotomy (SOMC), in services without adequate equipment are rarely reported in the literature. This study analyzes the viability of SOMC in the treatment of cerebral aneurysms, using exactly the same resources as pterional craniotomy (PC). The results of these two techniques are compared. 35 patients underwent SOMC, compared to 50 patients underwent CP (100 aneurysms in total), using the same microsurgical instruments. The following variables were compared: operative time, angiographic cure, length of intensive care unit stay during the post-operative period, surgical complications, length of hospital stay after surgery until hospital discharge, intraoperative aneurysm rupture, aesthetic satisfaction with the scar, and neurological status at discharge. SOMC had a significantly shorter operative time in relation to PC (213.9 ± 11.09 min and 268.6 ± 15.44 min, respectively) (p = 0.0081).With respect to the cosmetic parameters assessed by the Visual Analog Scale, the average for SOMC was 94.12 ± 1.92 points, and the average for PC was 83.57 ± 4.75 points (p = 0.036). SOMC was as effective as PC in relation to successful aneurysm clipping (p = 0.77). The SOMC technique did not show advantages over PC in any other variable. Even in a general neurosurgery service lacking a specific structure for minimally invasive surgeries, SOMC was feasible and effective for treating intracranial aneurysms, using the same set of microsurgical instruments used for PC, obtaining better results in operating time and cosmetic satisfaction.

Comparative Analysis of the Exposure and Surgical Freedom of the Endoscopic Extended Minipterional Craniotomy and the Transorbital Endoscopic Approach to the Anterior and Middle Cranial Fossae

BACKGROUND

Numerous minimally invasive approaches to the skull base have been successively developed. Knowledge of the surgical nuances of a specific approach may facilitate approach selection. This study sought to compare the nuances of an extended version of the minipterional craniotomy (EMPT) with those of the transorbital endoscopic approach (TOEA) to the anterior and middle cranial fossae (ACF and MCF, respectively).

OBJECTIVE

To quantitatively analyze and compare the area of exposure and surgical freedom between EMPT and TOEA to the ACF and MCF.

METHODS

EMPT and TOEA were carried out in 5 latex-injected cadaveric heads, bilaterally (10 sides). For each approach, the area of exposure, surgical freedom, and angle of attack were obtained with neuronavigation and statistically compared.

RESULTS

No significant difference was found between the mean area of exposure of EMPT and TOEA at the ACF and MCF (P = .709 and .317, respectively). The mean exposure area at the ACF was of 13.4 ± 2.6 cm2 (mean ± standard deviation) and 13.0 ± 1.9 cm2 for EMPT and TOEA, respectively. Except for the crista galli, EMPT afforded a larger area of surgical freedom at all targets. EMPT also achieved significantly greater attack angles in vertical axis except to the crista galli. The horizontal attack angles to all targets were similar between approaches.

CONCLUSION

EMPT and TOEA offer a comparable area of exposure at the ACF and MCF in the cadaver; however, the instrument maneuverability afforded by EMPT is superior. Further studies are necessary to better define their precise surgical application.

Zygomaticomaxillary buttress and its dilemma

Zygomatic fractures are the second most common fractures of the facial skeleton, after nasal bone fractures. Due to its uniqueness, the malar bone plays a very important role in maintaining appropriate facial contours. Zygomatic fractures can cause ocular and mandibular functional impairment, along with cosmetic defects. With the help of advanced imaging techniques and various treatment options, the management of zygomatic fractures has become more sophisticated and less invasive. This article discusses zygomatic fractures in detail: their clinical and radiographic features, and the various treatment options available.

[The trans-eyebrow supraorbital approach for removal of anterior cranial fossa and suprasellar meningiomas]

Over the past two decades, improvements in surgical tools, navigation systems, and endoscopic techniques have resulted in the widespread use of keyhole surgery for a wide range of skull base tumors. Currently, the trans-eyebrow supraorbital approach is being increasingly used in surgery for anterior cranial fossa and parasellar tumors.

MATERIAL AND METHODS

The study included 7 patients who underwent surgery for meningioma using the trans-eyebrow supraorbital approach at the Burdenko Neurosurgical Institute in the period between 2013 and 2017. The age of patients ranged from 51 to 75 years (median, 60 years); there were 5 females and 2 males. The maximum diameter of resected tumors ranged from 20 to 60 mm (median 40 mm).

RESULTS

Total resection of the tumor was achieved in all 7 cases, which was confirmed by postoperative MRI control. All 7 patients had a good cosmetic result. In 1 case, there was postoperative cerebrospinal fluid rhinorrhea due to incomplete closure of the frontal sinus, which required the patient to be re-operated. None of 7 cases was associated with injury to the main vessels or cavernous sinus.

CONCLUSION

Supraorbital trans-eyebrow craniotomy provides a minimally invasive approach for removing most anterior cranial fossa base and suprasellar tumors. The advantages of keyhole surgery, in comparison with traditional craniotomies, are minimal complications associated with the approach.

[A supraorbital trans-eyebrow approach in surgery of chiasmatic-sellar and anterior cranial fossa tumors]

OBJECTIVE

to analyze 31 resections of chiasmatic-sellar region (CSR) and anterior cranial fossa (ACF) tumors using the supraorbital trans-eyebrow approach (STA).

MATERIAL AND METHODS

We analyzed medical histories of 31 patients who underwent tumor resection using STA in the period between October 2013 and April 2017. We analyzed the age and gender of patients, size and location of the tumor, presence of a neurological deficit, vision and olfactory functions before and after surgery, surgery duration, amount of intraoperative blood loss, rate of frontal sinus trephination and nasal liquorrhea, hemorrhagic and ischemic complications after surgery, Simpson grade of tumor resection, patient's condition before and after surgery (Glasgow Outcome Scale and Karnofsky Scale), and degree of patient satisfaction with the cosmetic result of surgery. A total of 26 meningiomas (20 sphenoid plate, tubercle, and diaphragm tumors, 3 lesser sphenoid wing meningiomas, 2 orbital roof tumors, and 1 anterior clinoid process meningioma), 3 frontal lobe gliomas, and 2 pituitary adenomas were resected.

RESULTS

In all 31 operations, the approach was adequate and enabled tumor resection without lethal outcomes. The mean surgery duration was 174.6±64.4 min. The mean blood loss was 190±96.6 mL (50-380 mL). After surgery, none of the patients developed motor deficits and new epileptic seizures. Neurological deficit aggravation in the form of impaired vision and mental disorders occurred in 8 (25.8%) patients. Vision impaired in 4 (12.9%) patients, improved in 6 (19.3%) patients, and remained unchanged in 21 (67.7%) patients. An endocrinological deficit in the form of partial hypopituitarism developed in 3 (9.6%) patients; in 4 (12.9%) patients, there were mental disorders that regressed by the end of the first month of therapy. There were no intracerebral and subarachnoid hemorrhages. In 2 (6.4%) patients, small epidural hematomas were diagnosed, which did not require surgical treatment. There were only good outcomes (a GOS score of 4 or 5). After surgery, the median Karnofsky index in the STA group was 90±7. In all 31 (100%) patients, the postoperative wound healed by primary intention, without infectious complications and wound liquorrhea. One (4%) patient developed eyebrow palsy; 3 (12%) patients had hypoesthesia in the supraorbital region. The mean VAS score of patient satisfaction with the cosmetic result was 9.36 (median 10±1). The mean follow-up period was 16.2±13.5 months (2-38 months).

CONCLUSION

The STA is adequate for removal of CSR and ACF tumors under proper selection of patients. It provides an adequate view of anatomical structures and enables successful tumor resection through a less traumatic access.

Interfascial Dissection for Protection of the Nerve Branches to the Frontalis Muscles during Supraorbital Trans-Eyebrow Approach: An Anatomical Study and Technical Note

Introduction Preservation of the temporal branches of the facial nerve during anterolateral craniotomies is important. Damaging it can inflict undesirable cosmetic defects to the patient. The supraorbital trans-eyebrow approach (SOTE) is a versatile keyhole craniotomy but still has a high rate of frontalis muscle (FM) palsy. Objective Anatomical study to implement the interfascial dissection during the SOTE to preserve the nerves to the FM. Methods Slight modification of the standard technique of the SOTE was performed in 6 cadaveric specimens (12 sides). Results Distal rami to the FM were exposed. The standard "u-shape" incision of the FM can cross over the nerves. Alternatively, an "l-shape" incision was performed until the superior temporal line (STL). An interfascial dissection was performed near to the STL and the interfascial fat pad was used as a protective layer for the nerves. Conclusion Various pathologies can be addressed with the SOTE. In the majority of the cases the cosmetic results are good, but FM palsy remains a drawback of this approach. The interfascial dissection may be used in an attempt to prevent frontalis rami palsy.

Tumors of the anterior skull base

A variety of histologic tumor types are present in the anterior skull base. Primary tumors of this area may be derived from the bone, paranasal sinuses, nasopharynx, dura, cranial nerves, pituitary gland and brain. Symptoms are caused mostly through mass effect but, if the tumor becomes aggressive, also through invasion. Selection of surgical approaches to the anterior skull base is based upon balancing risk reduction with maximizing extent of resection. Here we review a spectrum of neoplastic entities found in the anterior skull base in adults and discuss clinical and radiographic presentation, treatment options, and outcomes. Surgical resection remains the mainstay in treatment of these tumors, particularly in the hands of experienced surgeons exercising proper patient and case selection.

The Supraorbital Keyhole Craniotomy through an Eyebrow Incision: Its Origins and Evolution

In the modern era of neurosurgery, the use of the operative microscope, rigid rod-lens endoscope, and neuronavigation has helped to overcome some of the previous limitations of surgery due to poor lighting and anatomic localization available to the surgeon. Over the last thirty years, the supraorbital craniotomy and subfrontal approach through an eyebrow incision have been developed and refined to play a legitimate role in the armamentarium of the modern skull base neurosurgeon. With careful patient selection, the supraorbital "keyhole" approach offers a less invasive but still efficacious approach to a number of lesions along the subfrontal corridor. Well over 1000 cases have been reported in the literature utilizing this approach establishing its safety and efficacy. This paper discusses the nuances of this approach, including the benefits and limitations of its use described through our technique, review of the literature, and case illustration.

[Modern surgery of meningiomas affecting anterior visual pathways]

Meningiomas are the most common form of primary intracranial tumors. If the anterior visual pathways are affected clinical visual compromise, visual field defects, oculomotor nerve disturbances or propotosis are predominant. Meningiomas of the anterior visual pathway remain therapeutically challenging due to the direct anatomical relationship to the circulus arteriosus cerebri, the cavernous sinus and cranial nerves. The therapy of choice is microsurgical resection. In many cases a curative approach can be achieved with modern surgical techniques and simultaneously maintaining patient quality of life. Problematic are cases in which resection would be associated with the risk of clinical impairment and in these cases radiotherapy is an important therapeutic option. In cases involving complex invasiveness an interdisciplinary treatment to control local clinical symptoms is favored.

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.

Supraorbital eyebrow craniotomy for removal of intraaxial frontal brain tumors: a technical note

OBJECTIVE

To present the utility and selection criteria for the supraorbital (SO) craniotomy, an approach commonly used to remove extraaxial tumors such as meningiomas and craniopharyngiomas, to resect intraaxial frontal brain lesions.

METHODS

All consecutive patients who underwent a SO craniotomy for an intraaxial lesion were retrospectively analyzed for lesion location, pathology, extent of resection, operative times, length of stay, and complications.

RESULTS

During 28 months, 10 patients (mean age, 67.6 years; 7 women) underwent 11 SO procedures to resect intraaxial brain lesions. Pathologies included metastatic carcinoma (n = 7), glioma (n = 2), and radiation necrosis (n = 1). The mean distance of the shortest trajectory to the lesion was 2.4 mm. Gross total or near-total removal was achieved in 80% of the cases. Median length of hospital stay was 3 days (range, 2-6 days); it was 2 days for patients admitted electively for SO craniotomy. There were no new neurologic deficits, postoperative hematomas, or cerebrospinal fluid leaks.

CONCLUSIONS

The SO "eyebrow" craniotomy is a safe and effective keyhole method to remove intraaxial frontal lobe lesions, particularly lesions of the frontal pole and orbitofrontal region, allowing for minimal disruption of normal brain parenchyma and promoting a rapid recovery and short hospital stay. Metastatic tumors and select gliomas in this area are most amenable to this approach. Deeper intraaxial tumors can also be effectively accessed via this route with excellent clinical outcomes.

Minimally invasive approaches to the anterior skull base

The use of minimally invasive approaches to the anterior skull base is a valuable tool to improving the treatment in patients with aggressive anterior skull base neoplasms. This article discusses the history, advantages and disadvantages relative to open approaches, the corridors and pathways used in approach, the equipment and operating room setup, perioperative care, and complication avoidance. Although outcomes are difficult to compare to open approaches, due to often small and varying patient cohorts, these approaches continue to gain acceptance as an effective treatment of anterior skull base tumors in the experienced surgeon's hands with proper patient selection.

Supra-orbital keyhole removal of anterior fossa and parasellar meningiomas

The improvement of surgical techniques as well as the introduction of new surgical instruments promoted the use of keyhole craniotomies in neurosurgery. We evaluated the technical aspects of the supra-orbital keyhole approach considering the indications, limitations, and complications of this approach to treat anterior cranial fossa and parasellar meningiomas. Twenty-four patients (21 females; mean age, 53 + or - 8.6 years) operated on between 2002 and 2006 through a supra-orbital eyebrow approach were studied. Maximal tumor diameter ranged from 1.6 to 6 cm. Gross total resection was done in 20 (83.3%). All tumors were histologically benign. Two patients (8%) experienced CSF rinorhea and another two patients suffered transitory diabetes insipidus (8%). One patient experienced transitory hemiparesis. There was one case of meningitis and one mortality. Follow-up ranged between 6 to 66 months (mean 31.5 + or - 20.1 months), with no recurrence. The supra-orbital keyhole craniotomy is a useful minimally invasive approach to treat selected anterior fossa and parasellar meningiomas.

Optic canal involvement in tuberculum sellae meningiomas: influence on approach, recurrence, and visual recovery

BACKGROUND

Tuberculum sellae meningiomas frequently extend into the optic canals.

OBJECTIVE

To emphasize the high frequency of optic canal (OC) involvement in tuberculum sellae meningiomas; the importance of opening the OC and of removing tumor within the canal; and the effect of this maneuver on visual outcome, recurrence rates, and surgical approach selection.

METHODS

A retrospective review of 58 patients with tuberculum sellae meningiomas treated surgically by the senior author (O.A.M) between 1993 and 2009 was performed. The frequency of involvement of the OC was documented, as well as the impact of removal of this part of the tumor on visual outcome and recurrence.

RESULTS

Total resection (Simpson grade 1) was achieved in 51 of 58 patients (87.9%). The tumor invaded the optic canal in 67%. Tumor resection from the optic nerve was achieved in all cases, and most (92%) underwent deroofing of the OC for this purpose. The dura over the tuberculum sella and/or planum sphenoidale was removed in all patients. Eighty-three percent required removal of affected hyperostotic bone. Vision was improved and/or spared in 88%. The average follow-up period was 23 months with 1 recurrence detected.

CONCLUSION

In the majority of cases, tuberculum sellae meningiomas extend into 1 or both OCs. Opening the OC for resection of the intracanalicular portion of the tumor enabled us to achieve excellent visual outcome. The supraorbital craniotomy remains the favored approach for removal of such tumors because it allows unroofing of both OCs, wide excision of the dura, and drilling of the affected bone.

Eyelid approach to the anterior cranial base

Skull base approaches play a fundamental role in modern neurosurgery by reducing surgical morbidity. Increasing experience has allowed surgeons to perform minimally invasive approaches without straying from the premises of skull base surgery. The eyelid approach has evolved from the orbitopterional osteotomy into a more effective and targeted approach to disease of the anterior cranial fossa. In this technique, after an incision is made on the supratarsal fold, the orbicularis oculi muscle is incised, and a myocutaneous flap composed of the elements of the anterior lamella is elevated. Subperiosteal dissection is used to expose the superior and lateral walls of the orbit, the superior and lateral orbital rim, and the frontosphenoidal suture. A MacCarty bur hole is drilled, and a frontal osteotomy is fashioned medial to the supraorbital notch and extending through the orbital roof back toward the orbital half of the MacCarty bur hole, exposing the frontobasal brain. A conventional microsurgical technique is used to treat tumors and aneurysms of the anterior cranial fossa under the operative microscope.

Five patients were treated for unruptured aneurysms of the anterior circulation (3 anterior communicating artery aneurysms, 1 ophthalmic artery aneurysm, and 1 posterior communicating artery aneurysm) using the eyelid approach. The mean aneurysm size was 5 mm, and all aneurysms were approached from the right side. Three tumors in the anterior fossa (2 suprasellar pituitary adenomas and 1 craniopharyngioma) were also excised using this approach. There was no surgical morbidity. Three months after surgery all patients presented excellent cosmetic results. The eyelid approach may be considered as an effective, cosmetically beneficial, and minimally invasive skull base approach to selected aneurysms and tumors of the anterior circulation.