Frontotemporal Orbitozygomatic Approach Research Articles

A quantitative comparative surgical analysis of the endoscopic transorbital approach and frontotemporal-orbitozygomatic approach for extradural exposure of the cavernous sinus.

Recently, the endoscopic superior eyelid transorbital approach (SETA) has emerged as a potential alternative to access the cavernous sinus (CS). Several previous studies have attempted to quantitatively compare the traditional open anterolateral skull base approaches with transorbital exposure; however, these comparisons have been limited to the area of exposure provided by the bone opening and trajectory, and fail to account for the main avenues of exposure provided by subsequent requisite surgical maneuvers. The authors quantitatively compare the surgical access provided by the frontotemporal-orbitozygomatic (FTOZ) approach and the SETA following applicable periclinoid surgical maneuvers, evaluate the surgical exposure of key structures in each, and discuss optimal approach selection. SETA and FTOZ approaches were performed with subsequent applicable surgical maneuvers on 8 cadaveric heads. The lengths of exposure of cranial nerves (CNs) II-VI and the cavernous internal carotid artery; the areas of the space accessed within the supratrochlear, infratrochlear, and supramaxillary (anteromedial) triangles; the total area of exposure; and the angles of attack were measured and compared. Exposure of the extradural CS was comparable between approaches, whereas access was significantly greater in the FTOZ approach compared with the SETA. The lengths of extradural exposure of CN III, V1, V2, and V3 were comparable between approaches. The FTOZ approach provided marginally increased exposure of CNs IV (20.9 ± 2.36 mm vs 13.4 ± 3.97 mm, p = 0.023) and VI (14.1 ± 2.44 mm vs 9.22 ± 3.45 mm, p = 0.066). The FTOZ also provided significantly larger vertical (44.5° ± 6.15° vs 18.4° ± 1.65°, p = 0.002) and horizontal (41.5° ± 5.40° vs 15.3° ± 5.06°, p < 0.001) angles of attack, and thus significantly greater surgical freedom, and provided significantly greater access to the supratrochlear (p = 0.021) and infratrochlear (p = 0.007) triangles, and significantly greater exposure of the cavernous internal carotid artery (17.2 ± 1.70 mm vs 8.05 ± 2.37 mm, p = 0.001). Total area of exposure was also significantly larger in the FTOZ, which provided wide access to the lateral wall of the CS as well as the possibility for intradural access. This is the first study to quantitatively identify the relative advantages of the FTOZ and transorbital approaches at the target region following requisite surgical maneuvers. Understanding these data will aid in selecting an optimal approach and maneuver set based on target lesion size and location.

Quantitative Anatomical Comparison of Surgical Approaches to Meckel's Cave.

Meckel's cave is a challenging surgical target due to its deep location and proximity to vital neurovascular structures. Surgeons have developed various microsurgical transcranial approaches (MTAs) to access it, but there is no consensus on the best method. Newer endoscopic approaches have also emerged. This study seeks to quantitatively compare these surgical approaches to Meckel's cave, offering insights into surgical volumes and exposure areas. Fifteen surgical approaches were performed bilaterally in six specimens, including the pterional approach (PTA), fronto-temporal-orbito-zygomatic approach (FTOZA), subtemporal approach (STA), Kawase approach (KWA), retrosigmoid approach (RSA), retrosigmoid approach with suprameatal extension (RSAS), endoscopic endonasal transpterygoid approach (EETPA), inferolateral transorbital approach (ILTEA) and superior eyelid approach (SEYA). All the MTAs were performed both with 10 mm and 15 mm of brain retraction, to consider different percentages of surface exposure. A dedicated navigation system was used to quantify the surgical working volumes and exposure of different areas of Meckel's cave (ApproachViewer, part of GTx-Eyes II, University Health Network, Toronto, Canada). Microsurgical transcranial approaches were quantified with two different degrees of brain retraction (10 mm and 15 mm). Statistical analysis was performed using a mixed linear model with bootstrap resampling. The RSAS with 15 mm of retraction offered the maximum exposure of the trigeminal stem (TS). If compared to the KWA, the RSA exposed more of the TS (69% vs. 46%; p = 0.01). The EETPA and ILTEA exposed the Gasserian ganglion (GG) mainly in the anteromedial portion, but with a significant 20% gain in exposure provided by the EETPA compared to ILTEA (42% vs. 22%; p = 0.06). The STA with 15 mm of retraction offered the maximum exposure of the GG, with a significant gain in exposure compared to the STA with 10 mm of retraction (50% vs. 35%; p = 0.03). The medial part of the three trigeminal branches was mainly exposed by the EETPA, particularly for the ophthalmic (66%) and maxillary (83%) nerves. The EETPA offered the maximum exposure of the medial part of the mandibular nerve, with a significant gain in exposure compared to the ILTEA (42% vs. 11%; p = 0.01) and the SEY (42% vs. 2%; p = 0.01). The FTOZA offered the maximum exposure of the lateral part of the ophthalmic nerve, with a significant gain of 67% (p = 0.03) and 48% (p = 0.04) in exposure compared to the PTA and STA, respectively. The STA with 15 mm of retraction offered the maximum exposure of the lateral part of the maxillary nerve, with a significant gain in exposure compared to the STA with 10 mm of retraction (58% vs. 45%; p = 0.04). The STA with 15 mm of retraction provided a significant exposure gain of 23% for the lateral part of the mandibular nerve compared to FTOZA with 15 mm of retraction (p = 0.03). The endoscopic approaches, through the endonasal and transorbital routes, can provide adequate exposure of Meckel's cave, especially for its more medial portions, bypassing the impediment of major neurovascular structures and significant brain retraction. As far as the most lateral portion of Meckel's cave, MTA approaches still seem to be the gold standard in obtaining optimal exposure and adequate surgical volumes.

Anterolateral Routes to the Skull Base-The Frontotemporal Approaches and Exposure of the Sellar and Parasellar Regions.

Surgical approaches to the sellar and parasellar regions are highly challenging due to the densely packed nature of the traversing neurovasculature. The frontotemporal-orbitozygomatic approach offers a wide angle of exposure for the management of lesions involving the cavernous sinus, parasellar region, upper clivus, and adjacent neurovascular structures. It combines the pterional approach with different osteotomies that remove the superior and lateral walls of the orbit and zygomatic arch. Extradural exposure and preparation of the periclinoid region, whether as initial preparation for a combined intraextradural approach to deep-seated skull base targets or as the main avenue of surgical exposure, can substantially enlarge surgical corridors and minimize the need for brain retraction in this very confined microsurgical space. We provide a stepwise description of how we perform the fronto-orbitozygomatic approach and an associated series of surgical maneuvers and techniques that can be utilized in a variety of anterior and anterolateral approaches, either alone or in combination, to tailor exposure to a given lesion. These techniques are not limited to traditional skull base approaches and represent a valuable addition to every neurosurgeon's armamentarium as enhancements to common surgical approaches.

Tailored Surgical Access to the Cavernous Sinus and Parasellar Region: Assessment of Cavernous Sinus Entry Corridors and the Periclinoid and Pericavernous Surgical Maneuvers

Lesions involving the cavernous sinus (CS) represent some of the most challenging pathologies of the skull base owing to the dense traversing and surrounding neurovasculature. Extradural exposure and preparation of this region, whether as initial preparation for a combined intra-extradural approach or as the main avenue of surgical exposure, can enlarge surgical corridors and minimize the need for brain retraction in this very confined space. We provide a detailed assessment of the entry corridors to the CS that are available within each approach, the surgical exposure and freedom provided by each of these corridors, and demonstrate how extradural and intradural preparation of these corridors can be used to widen the available working space and facilitate surgery. Pterional, frontotemporal-orbital, frontotemporal-orbitozygomatic, frontotemporal-zygomatic, perilabyrinthine transtentorial, and endoscopic transnasal transsphenoidal approaches were performed on cadaveric heads to access the perisellar and CS regions. Periclinoid maneuvers (extradural cutting of the meningo-orbital band, anterior clinoidectomy, unroofing of the optic canal, opening of the superior orbital fissure, displacement of the extra-annular structures, opening of the annulus of Zinn, and interdural dissection), pericavernous maneuvers (intradural cutting of the distal dural ring, mobilization of the supraclinoid internal carotid artery, opening of the oculomotor porus, and mobilization of cranial nerve (CN) III), peritrigeminal extensions (extradural mobilization of CN V2 [maxillary] and/or V3 [mandibular]), and other surgical maneuvers were performed and evaluated. The CS was divided into 8 anatomical compartments and 9 entry corridors were described, and exposure and freedom were assessed accordingly. Intradurally, the standard unextended pterional, frontotemporal-orbital, and frontotemporal orbitozygomatic transsylvian approaches provided access solely to the parasellar entry corridor into the superior wall of the CS. Expanding these approaches with extradural periclinoid maneuvers allowed for subsequent application of the intradural pericavernous maneuvers and enlargement of the parasellar corridor and exposure of the carotid cave. Extradurally, the frontotemporal-orbital approach could be expanded via application of periclinoid maneuvers, which provided access to the anterior portions of the main lateral wall entry corridors. The frontotemporal-orbitozygomatic approach could also be expanded with periclinoid maneuvers to provide extradural access to all 6 lateral wall entry corridors. The extradural frontotemporal-zygomatic approach only provided exposure following interdural dissection, which allowed for access to the inferolateral entry corridors into the lateral wall. Extradural peritrigeminal extension in the frontotemporal-orbitozygomatic and frontotemporal-zygomatic approaches allows for enlargement of the supramaxillary and pre- and postmandibular corridors. The perilabyrinthine approach to the posterior wall was enlarged with opening of Dorello's canal and the endoscopic transnasal transsphenoidal approach was enlarged with opening of the optic canal. Targeted extradural preparation optimizes exposure and significantly improves access to deep-seated targets by enhancing surgical maneuverability through the unlocking of neurovascular structures and widening of surgical corridors without the need for additional brain retraction.

Quantitative Anatomic Comparison of Endoscopic Transnasal and Microsurgical Transcranial Approaches to the Anterior Cranial Fossa.

Several microsurgical transcranial approaches (MTAs) and endoscopic transnasal approaches (EEAs) to the anterior cranial fossa (ACF) have been described. To provide a preclinical, quantitative, anatomic, comparative analysis of surgical approaches to the ACF. Five alcohol-fixed specimens underwent high-resolution computed tomography. The following approaches were performed on each specimen: EEAs (transcribriform, transtuberculum, and transplanum), anterior MTAs (transfrontal sinus interhemispheric, frontobasal interhemispheric, and subfrontal with unilateral and bilateral frontal craniotomy), and anterolateral MTAs (supraorbital, minipterional, pterional, and frontotemporal orbitozygomatic approach). An optic neuronavigation system and dedicated software (ApproachViewer, part of GTx-Eyes II-UHN) were used to quantify the working volume of each approach and extrapolate the exposure of different ACF regions. Mixed linear models with random intercepts were used for statistical analyses. EEAs offer a large and direct route to the midline region of ACF, whose most anterior structures (ie, crista galli, cribriform plate, and ethmoidal roof) are also well exposed by anterior MTAs, whereas deeper ones (ie, planum sphenoidale and tuberculum sellae) are also well exposed by anterolateral MTAs. The orbital roof region is exposed by both anterolateral and lateral MTAs. The posterolateral region (ie, sphenoid wing and optic canal) is well exposed by anterolateral MTAs. Anterior and anterolateral MTAs play a pivotal role in the exposure of most anterior and posterolateral ACF regions, respectively, whereas midline regions are well exposed by EEAs. Furthermore, certain anterolateral approaches may be most useful when involvement of the optic canal and nerves involvement are suspected.

Microsurgical Management of Complex Hypothalamic Hamartomas in the Era of Minimally Invasive Therapy: A Case Series and Narrative Review

There has been a paradigm shift in the management of hypothalamic hamartoma (HH) from traditional microsurgical techniques to less invasive alternatives. However, large and extensive HH may fail to respond to these therapies, necessitating craniotomies. All patients who underwent microsurgical resection of a complex HH by the 2 senior authors from 2011 to 2021 were included. Charts were retrospectively reviewed and demographic, clinical, imaging, and outcome data were recorded. Eight patients (mean age, 7 years) were included. Two had failed previous treatments. All 7 presented with gelastic seizures and cognitive dysfunction, 6 showed central precocious puberty, and 3 had behavioral problems. The mean lesion size was 21.6 mm and all had interpeduncular extension, 5 had intraventricular extension (Delalande type I, 3; type III, 4; type IV, 1). A frontotemporal orbitozygomatic approach with optic nerve decompression was used in all patients, supplemented by another approach in 3 (endoscopic transventricular, 3; transcallosal, 1). Gross total resection was achieved in 6 patients and subtotal resection in 2. Transient complications occurred in 3 patients (37.5%): self-limited sodium imbalance (n= 3), subdural hygroma (n= 2). Permanent complications occurred in 2 patients (25%): perforator infarct (n= 1) and short-term memory loss (n= 1). All patients experienced seizure resolution with preserved hypothalamic-pituitary axis function. After a mean follow-up of 41 months (range, 2-66 months), 7 patients remained seizure free, and 1 had rare seizures. Cognitive and behavioral symptoms improved in all patients. For large HH with interpeduncular extension, microsurgery via the frontotemporal orbitozygomatic approach is a safe and highly effective treatment modality.

Analysis on endoscopic endonasal approach combined with the frontotemporal orbitozygomatic approach under the microscope for skull base tumor with intra and extra-cranial involvement

Objective: To evaluate the application of combination use of endoscopic endonasal approach combined with the frontotemporal orbitozygomatic approach microscopically in skull base tumor with intra and extra-cranial involvement. Methods: A total of 7 patients (4 males and 3 females, aging from 27 to 65 years old, with a medium age of 48) undergone complicated skull base surgeries via endoscopic endonasal approach combined with the frontotemporal orbitozygomatic approach microscopically from May 2016 to January 2018 were reviewed respectively. The patients included 2 cases of recurrent invasive pituitary adenoma, 3 cases of basal skull meningiomas, 1 case of clivus chondrosarcoma, and 1 case of recurrent nasopharyngeal carcinoma. The lesion extensively infiltrated nasal cavity, extending to the paranasal sinus, bilateral cavernous sinus, sellar region, suprasellar, superior clivus, temporal lobe, pterygopalatine fossa, infratemporal fossa and important intracranial vessels. All the 7 patients were treated under general anesthesia by endoscopic endonasal approach combined with frontotemporal orbitozygomatic approach under the microscope. Total excision rate, intraoperative and postoperative complications and postoperative curative effect were observed. All of them were followed up for 6 to 12 months. The Glasgow Outcome Scale (GOS) was used to evaluate the prognosis. Result: Total tumor removal was performed in 5 cases, subtotal removel in 2 cases. There was no complication during the operation. Postoperative severe complications occurred in 2 cases, including 1 case of cerebrospinal fluid rhinorrhea and intracranial infection, which was cured by lumbar cistern drainage and intrathecal injection; 1 case occurred oculomotor nerve paralysis, which recovered during follow-up. Postoperative complications occurred in 1 case of trochlear nerve dysfunction, 2 cases of facial numbness, and 1 case of tinnitus. During follow-up, all patients recovered to varying degrees. There was no bleeding and death after the operation. No tumor recurred during the follow-up period. All patients were recovered well with GOS grade Ⅳ-Ⅴ. Conclusions: Endoscopic transnasal approach combined with microscopic frontotemporal orbitozygomatic approach can remove tumors in one stage, reduce surgical complications and improve surgical effect. It has good application prospects and is suitable for excising complex intracranial and extracranial communicating tumors of widely involving sellar, clivus and petrous apex area.

Extended pterional approach with orbital flattening for suprasellar and parasellar lesions

Background and aim The aim of this study was to investigate the advantages of the extended pterional approach and compare it with more invasive and less-invasive similar approaches. Patients and method s This study is an observational retrospective case-series study and descriptive statistics was used. Twelve patients with suprasellar and parasellar lesions were managed in the period between January 2016 and January 2019. Preoperative and postoperative clinical and radiological assessment were done for each patient. Results Twelve cases were done via this approach. There were nine females and three males. Age ranges from 2 to 55 years with a mean of 31.7 years. Regarding pathology, eight (67%) cases were meningiomas, three (25%) cases were craniopharyngiomas, while one (8.3%) case was pituitary adenoma. Most of the cases (91.7%) were presented with visual affection. The lesion was excised totally (gross total resection) in seven (58.3%) out of the 12 cases. Visual affection improved in seven (63.6%) out of 11 cases. Regarding complications, one case experienced permanent hemiparesis. One patient had deep-vein thrombosis that had been treated. One case had seizures. Approach-related complications: two cases had periorbital edema that disappeared within 1 week. One case had a rim of subdural hematoma. Frontalis nerve injury occurred in two cases, one of them improved within 6 months. We do not have a permanent cosmetic deformity with this approach. Conclusion The extended pterional approach has less functional and cosmetic complications and it can be done in lesser time than frontotemporal–orbitozygomatic approach. The exposure is much larger than conventional pterional approach.

Immersive Surgical Anatomy of the Frontotemporal-Orbitozygomatic Approach.

The frontotemporal-orbitozygomatic (FTOZ) approach is widely used for accessing anterolateral lesions in skull base surgery. Many studies have described the technique and quantified the surgical exposure and freedom provided by the FTOZ approach. However, few studies have provided a detailed analysis of the technique and surgical landmarks using three-dimensional (3D) models. In this study, we aimed to create a collection of volumetric models (VMs) and stereoscopic media on the step-by-step surgical technique of the FTOZ approach using cadaveric dissections. The FTOZ approach was divided into eight major steps: positioning, incision of the skin, dissection of scalp flap, mobilization of the temporalis muscle, dissection of periorbita, craniotomy, drilling of basal structures, and dural opening. The MacCarty keyhole and inferior orbital fissure are major surgical landmarks that were referenced for the six bony cuts. Photogrammetry and structured light scanning were used to construct high-resolution VMs. We illustrated the two-piece FTOZ craniotomy, followed by the one-piece and three-piece FTOZ craniotomies. Stereoscopic images, videos, and VMs were produced for each step of the surgical procedure. In addition, the mini-orbitozygomatic (MOz) and orbitopterional (OPt) approaches were considered and described as possible alternatives to the FTOZ approach. Recent advances in 3D technology can be implemented in neurosurgical practice to further enhance our spatial understanding of neurovascular structures. Surgical approaches should be carefully selected and tailored according to the patient’s unique pathology and needs.

Pediatric Intracavernous Sinus Lesions: A Single Institutional Surgical Case Series and Review of the Literature.

Pediatric intracavernous sinus tumors are exceedingly rare and thus poorly characterized. Their neurosurgical management is challenging and diagnostic, and management guidelines are limited. To report our institutional experience with the surgical resection of pediatric intracavernous sinus tumors. We also compare and contrast our results with the 14 cases of pediatric intracavernous sinus lesions in the current literature. A retrospective descriptive analysis of consecutive pediatric patients (ages 0-18 yr) presenting to our institution with a diagnosis of an intracavernous sinus lesion was performed. From January 2012 to January 2017, 5 cases were identified. Eleven patients with secondary invasion of the cavernous sinus (2 meningiomas, 7 pituitary adenomas) or dermoid tumors involving the cavernous sinus (2) were not included in our review. Surgical resection via a frontotemporal orbitozygomatic approach was performed in all cases by a single senior neurosurgeon (M.L.). There were no perioperative or postoperative complications attributable to the surgery or approach. Four of 5 patients remained neurologically stable throughout the perioperative and postoperative period. The fifth patient had a complete resolution of their cranial neuropathies postoperatively. A pathological diagnosis that guided long-term management was obtained in all cases. Neurosurgical management of pediatric cavernous sinus lesions can be safely performed and critically guide future therapies. Surgeon familiarity with cavernous sinus and skull-base anatomy is critical to the successful management of these patients. The benefits of surgery should be balanced against the potential complications and need for a tissue diagnosis in children. The senior author had a significant experience with cavernous sinus approaches in adults prior to initiating use of the approach in the pediatric population.

The Interlenticulostriate Approach to Very High-Riding Distal Basilar Trunk Aneurysms.

Most high-riding distal basilar trunk aneurysms can be surgically approached via the transsylvian route and its orbitozygomatic variant. However, on rare occasions, the basilar bifurcation may be unusually high and an approach above the carotid terminus may be required. In this cadaveric study, we sought to determine the feasibility and exposure limits of the interlenticulostriate approach (ILSA). A standard transsylvian approach was performed in 10 cerebral hemispheres of 5 formalin-fixed, silicone-injected cadaver heads. The interpeduncular cistern was exposed via the opticocarotid window, carotid-oculomotor window, and supracarotid ILSA window. The latter was measured and an aneurysm clip or ventriculostomy stylet was placed as high as possible through each corridor. Using noncontrast 3-D rotational angiography, clip/stylet positions were measured relative to the dorsum sellae. ILSA provided a 9.4 × 4.6 mm mean surgical corridor, just enough room for a standard clip applier. This space was limited by the carotid bifurcation inferiorly, the lenticulostriate arteries medially and laterally, and the optic tract superiorly. There was no difference between opticocarotid and carotid-oculomotor windows, in terms of clip position (+8.9 vs +8.6 mm, respectively; P = .78). In contrast, ILSA provided significantly improved superior exposure, compared with either approaches (mean stylet position: +14.3 mm; P = .005). The exposure benefit afforded by ILSA was consistent across all 10 hemispheres, ranging from +2.5 to +8 mm. For high-riding distal basilar trunk aneurysms that cannot be reached via the frontotemporal orbitozygomatic approach, ILSA can provide a viable route of access. Vascular neurosurgeons should be familiarized with this approach.

The extended transorbital craniotomy: an anatomic study.

Supra-/transorbital approaches are mostly limited to suprasellar and anterior fossa pathologies, whereas lateral supraorbital approaches provide less retrosellar exposure and less overall operative volume, especially in the temporal region. Our cadaveric study proposes removal of the lesser and greater wings of the sphenoid bone to increase both the lateral angle typically achieved with pterional approaches and exposure to the temporal lobe and perisellar region. In 5 cadaveric specimens, our 3 steps to expand transorbital exposures included the following: step 1, standard transorbital craniotomy via a 3-cm supra-eyebrow incision; step 2, removal of the lesser sphenoid wing completed extradurally; and step 3, partial removal of the greater sphenoid wing. Operative extension in sylvian, parasellar, and anterolateral temporal exposures were quantified for each step (t test). Step 2 provided the greatest increased exposure in the sylvian and parasellar regions compared with step 3, whereas step 3 provided a significant proportion of the exposure in the lateral temporal region. Finally, the lateral view progressively increased with each subsequent step. Our 3-step removal of the lesser and greater wings of the sphenoid bone quantified increased sylvian, anterior temporal, and parasellar exposures for this minimally invasive approach with excellent cosmesis. Its increases the anterolateral view (similar to a subfrontal pterional approach) and offers potential applications to vascular and neoplastic (ie, sphenoid meningiomas) pathologies classically treated via a pterional or frontotemporal orbitozygomatic approach.

Injury to the Temporal Lobe via Medial Transorbital Entry of a Toothbrush

Objectives Intracranial penetration by foreign bodies entering via the orbit represent an unusual form of traumatic brain injury. Nevertheless, much is at stake with high risk for cranial nerve and neurovascular injury. We present a case where the bristled end of a toothbrush entered the brain as a projectile via the superior orbital fissure and discuss considerations for surgical management.Setting A 35-year-old woman suffered a periorbital injury after her husband threw an electric toothbrush at a wall and the head of the toothbrush became a missile that projected through her superior orbital fissure and into her right temporal lobe. She complained of headache and incomplete vision loss in the affected eye.Intervention After obtaining a cerebrovascular angiogram, we proceeded with emergent orbital decompression and anterograde extraction of the foreign body via a modified frontotemporal orbitozygomatic approach with drilling of the skull base allowing for en bloc removal of the toothbrush.Conclusions The patient recovered well with improvement in her vision and partial third and sixth nerve palsies. This report illustrates a unique mechanism of injury with a novel intracranial foreign body. We review the neurosurgeon's need for prompt management with an approach customized to the structure of the offending object, the damaged elements, and the surrounding cranial nerves and vascular anatomy.

Injury to the Temporal Lobe via Medial Transorbital Entry of a Toothbrush

Objectives Intracranial penetration by foreign bodies entering via the orbit represent an unusual form of traumatic brain injury. Nevertheless, much is at stake with high risk for cranial nerve and neurovascular injury. We present a case where the bristled end of a toothbrush entered the brain as a projectile via the superior orbital fissure and discuss considerations for surgical management. Setting A 35-year-old woman suffered a periorbital injury after her husband threw an electric toothbrush at a wall and the head of the toothbrush became a missile that projected through her superior orbital fissure and into her right temporal lobe. She complained of headache and incomplete vision loss in the affected eye. Intervention After obtaining a cerebrovascular angiogram, we proceeded with emergent orbital decompression and anterograde extraction of the foreign body via a modified frontotemporal orbitozygomatic approach with drilling of the skull base allowing for en bloc removal of the toothbrush. Conclusions The patient recovered well with improvement in her vision and partial third and sixth nerve palsies. This report illustrates a unique mechanism of injury with a novel intracranial foreign body. We review the neurosurgeon's need for prompt management with an approach customized to the structure of the offending object, the damaged elements, and the surrounding cranial nerves and vascular anatomy.

Management of the optic canal invasion and visual outcome in spheno-orbital meningiomas

ObjectiveSpheno-orbital meningiomas often present with visual deficit due to invasion of the optic canal by the tumor. This study discusses the reasons of visual impairment, the choice of the surgical approach according to the type of optic canal involvement, and the factors correlated to the visual outcome in patients harboring a spheno-orbital meningioma. Materials and methodsA surgical series of 60 spheno-orbital meningiomas is reviewed. The preoperative visual symptoms, the involvement of the optic canal in both neuroradiological studies and surgical descriptions, the different surgical approaches are reviewed. These data are correlated with the postoperative visual outcome. ResultsThe 60 spheno-orbital meningiomas were classified in 4 types according to the intraorbital tumor localization: type I, supero-lateral (18 cases); type II, inferomedial (8 cases); type III, orbital apex (22 cases); type IV, diffuse (12 cases). Thirty-six of the 60 patients (60%) had variable decrease of the visual acuity on the tumor side. Forty-three patients (71.6%) had tumor extension into the optic canal on imaging studies. On the whole, 36 patients among 43 with invasion of the optic canal (83.7%) had preoperative visual dysfunction; on the other hand, none among 17 patients without tumor invasion of the optic canal had visual dysfunction.The surgical approaches according to the tumor location were as follows. A supraorbital-pterional approach was used in the 8 inferomedial tumors, in the 22 orbital apex tumors, and in 9/12 diffuse tumors; these last two types had concentric involvement of the optic canal. Three diffuse tumors with significant extension in the infratemporal fossa were operated on via a frontotemporal-orbitozygomatic approach. A wide decompression of the optic canal was performed in all cases, excepting in two inferomedial tumors without optic canal invasion. The 18 patients with lateral tumors were approached via a lateral orbitocranial approach, including removal of the sphenoid wing and lateral orbital wall without bone flap; the resection of the lateral aspect of the optic canal was performed in the 3 cases with canal invasion.Postoperative improvement of the visual function was observed in 18 of 36 cases with visual dysfunction (50%). The rate of visual improvement was significantly higher in cases with lateral involvement (3/3 or 100%) than in those with concentric involvement of the optic canal (11/27 or 40.7%). ConclusionThe invasion of the optic canal by the tumor is the main reason of visual dysfunction in patients with spheno-orbital meningiomas. A wide opening of the optic canal must be performed routinely in patients with orbital apex and diffuse orbital tumors, where there is concentric invasion of the optic canal wall. In these cases the supraorbital-pterional approach is the technique of choice. In selected cases with lateral intraorbital tumors and invasion of the lateral aspect of the optic canal the complete tumor resection coupled with good decompression of the optic nerve may be achieved via a less invasive lateral orbitocranial approach without craniotomy.

The frontotemporal-orbitozygomatic approach: reconstructive technique and outcome

The frontotemporal-orbitozygomatic (FTOZ) approach, also known as "the workhorse of skull base surgery," has captured the interest of many researchers throughout the years. Most of the studies published have focused on the surgical technique and the gained exposure. However, few studies have described reconstructive techniques or functional and cosmetic outcomes. The goal of this study was to describe the surgical reconstruction after the FTOZ approach and analyze the functional and cosmetic outcomes. Seventy-five consecutive patients who had undergone FTOZ craniotomy for different reasons were selected. The same surgical (one-piece FTOZ) and reconstructive techniques were applied in all patients. The functional outcome was measured by complications related to the surgical approach: retro-orbital pain, exophthalmos, enophthalmos, ocular movement restriction, cranial nerve injuries, pseudomeningocele (PMC) and secondary surgeries required to attain a reconstructive closure. The cosmetic outcome was evaluated by analyzing the satisfaction of the patients and their families. Questionnaires were conducted later in the postoperative period. A statistical analysis of the data obtained from the charts and questions was performed. Of the 75 patients studied, 59 had no complications whatsoever. Ocular movement restriction was found in two patients (2.4 %). Cranial nerve injury was documented in seven patients (8.5 %). One patient (1.2 %) underwent surgical repair of a cerebrospinal fluid (CSF) leak from the initial surgery. Two patients (2.4 %) developed delayed postoperative pseudomenigocele. One patient (1.2 %) developed intraparenchymal hemorrhage (IPH). Full responses to the questionnaires were collected from 28 patients giving an overall response rate of 34 %. Overall, 22 patients (78.5 %) were satisfied with the cosmetic outcome of surgery. The reconstruction after FTOZ approach is as important as the performance of the surgical technique. Attention to anatomical details and the stepwise reconstruction are a prerequisite to the successful preservation of function and cosmesis. In our series, the orbitozygomatic osteotomy did not increase surgical complications or alter cosmetic outcomes.

Follicular Thyroid Carcinoma with Insular Component Metastatic to the Sphenoid Wing

A 60-year-old woman with a history of follicular thyroid carcinoma with insular component presented with a large asymptomatic sphenoid wing mass discovered on routine surveillance. Therapeutic options including observation, surgical excision, radiation therapy, and I-131 therapy were initially debated. Each option presented potential morbidity. The patient initially underwent treatment with iodine-131 (I-131) with a decrease in size of the mass over 8 months. Subsequent MRI at 11 months revealed enlargement of the sphenoid wing mass with involvement of the orbital apex, cavernous sinus, and the middle cranial fossa. The patient ultimately underwent surgical resection and debulking via a frontotemporal orbitozygomatic approach. Although rare, follicular thyroid carcinoma with insular features often has an aggressive clinical course with local invasion and distant metastases. It carries a poor prognosis and can be difficult to treat due to a lack of available treatment protocols and the known morbidity of current therapies.

The Fronto-Temporal-Orbito-Zygomatic Approach: Reconstructive Technique and Outcome

Objective: The fronto-temporal-orbito-zygomatic (FTOZ) approach, also known as “the workhorse of skull base surgery,” has captured the interest of many researchers throughout the years. Most of the studies published have focused on the surgical technique and the gained exposure. However, few studies have described reconstructive techniques or functional and cosmetic outcomes. The goal of this study is to describe the surgical reconstruction after the FTOZ approach and analyze the functional and cosmetic outcomes.

EXPOSURE OF THE DISTAL CERVICAL SEGMENT OF THE INTERNAL CAROTID ARTERY USING THE TRANS-SPINOSUM CORRIDOR

Exposure of the most distal portion of the cervical segment of the internal carotid artery (ICA) is technically challenging. Previous descriptions of cranial base approaches to expose this segment noted facial nerve manipulation, resection of the glenoid fossa, and significant retraction or resection of the condyle. We propose a new approach using the frontotemporal orbitozygomatic approach to expose the distal portion of the cervical segment of the ICA via the trans-spinosum corridor. Six formalin-fixed injected heads were used for cadaveric dissection. Two blocs containing the carotid canal and surrounding region were used for histological examination. The ICA lies immediately medial to the vaginal process. The carotid sheath attaches laterally to the vaginal process. With use of the trans-spinosum corridor, the surgeon's line of sight courses in front of the temporomandibular joint, through the foramen spinosum, spine of the sphenoid, and vaginal process. Removal of the vaginal process exposes the vertical portion of the petrous segment of the ICA. The loose connective tissue space between the adventitia and the carotid sheath is easily entered from above. Incision of the carotid sheath exposes the ICA without disruption of the temporomandibular joint. Control of the cervical segment of the ICA can be critical when dealing with cranial base tumors that invade or surround the petrous segment of the ICA. This novel technique through the trans-spinosum corridor can effectively expose the distal portion of the cervical segment of the ICA without causing manipulation of the facial nerve and while maintaining the integrity of the temporomandibular joint.

EXTENSION OF THE ONE-PIECE ORBITOZYGOMATIC FRONTOTEMPORAL APPROACH TO THE GLENOID FOSSA

Resection of the glenoid fossa has been described as part of cranial approaches to the clivus and subtemporal approaches. However, radical resection carries a significant risk of postoperative temporomandibular joint dysfunction. We examine a simple variation of our previously described one-piece frontotemporal orbitozygomatic (FTOZ) osteotomy that adds en bloc resection of the root of the zygomatic arch and a portion of the glenoid fossa. Five cadaveric fixed heads injected with colored silicone underwent an FTOZ osteotomy that extended to the root of the zygomatic arch and glenoid fossa. A step-by-step guide to the surgical technique is described, with illustrations to depict the glenoid fossa keyhole and bony cuts that free the zygomatic arch and portions of glenoid fossa. The first cut was made through the posterior root, and the second cut was made through the anterior root of the zygomatic arch. In this cadaveric study, extension of the one-piece FTOZ approach included the posterior root of the zygoma and the lateral part of the glenoid fossa. En bloc resection of the glenoid fossa and root of the zygomatic arch, together with the FTOZ osteotomy, facilitated reconstruction of the temporomandibular joint and increased the amount of exposure obtained with this FTOZ osteotomy. Comprehensive understanding of functional outcomes awaits further clinical study.