Cranio-Orbital Pretemporal Approach for Microsurgical Resection of Hypothalamic Rosette Forming Glioneuronal Tumor with Reversal of Preoperative Blindness: 2-Dimensional Operative Video.

The hypothalamic region is susceptible to involvement of several processes.1 Lesions in this region remain challenging for surgical access and treatment. Strategies include both endoscopic and microsurgical approaches.2 A cranio-orbital approach with extradural clinoidectomy and optic canal unroofing provides the necessary corridor to visualize and decompress the optic nerve/chiasm and remains an important tool in achieving complete tumor resection with favorable functional and visual outcomes.3-12 Endoscope assistance in transcranial surgery is well established, used to provide direct visualization of hidden adjacent tissues.13 A 25-year-old woman presented with headache and progressive visual loss to blindness (hand waving and light perception) on admission. Magnetic resonance imaging demonstrated a 28-mm-diameter tumor in the hypothalamic region with no significant postcontrast enhancement. She underwent right cranio-orbital craniotomy, extradural anterior clinoidectomy, and optic canal unroofing with a 2-mm high-speed diamond drill and copious irrigation. After ipsilateral falciform ligament release, the tumor capsule was coagulated, sharply opened, and resected in a piecemeal fashion. Endoscopic assistance warranted the removal of hidden parts and confirmed tumor removal. Histopathology and next-generation sequencing confirmed the diagnosis of rosette-forming glioneural tumor. Follow-up revealed gross total tumor removal on magnetic resonance imaging and complete recovery of visual function as per ophthalmologist examination. Rosette-forming glioneural tumors are considered rare and classified as World Health Organization grade I tumors usually found in the fourth ventricle.14 To our knowledge, we present the first operative video (Video 1) demonstrating the removal of rosette-forming glioneural tumor in the hypothalamic region with endoscopic assistance.

Lateral micro-orbitotomy as the technique of choice for orbital pseudotumor in IgG4-RD. Case report and review of the literature.

Immunoglobulin G4-related disease (IgG4-RD) is characterized by a systemic fibroinflammatory infiltrate that often involves the orbit in addition to other tissues. Thus it has to be considered in the differential diagnosis of orbital tumors. We report the clinical case of a 64-year-old woman who presented with right mydriasis, progressive proptosis and paralysis of the third cranial nerve of 1 year of evolution. Cranial MRI identified an intraconal lesion of the right orbit, located between the external and inferior rectus muscles and the optic nerve, and she was scheduled for surgery by transcranial approach with lateral micro-orbitomy. A satisfactory macroscopic excision was achieved with no remarkable complications and a definitive deferred histological result of pseudotumor by IgG4-RD. Follow-up for 24 months showed no tumor recurrence, and the patient clinically improved from ophthalmoplegia. This case highlights the efficacy of lateral orbitotomy in the etiologic diagnosis and successful therapeutic outcome of complex orbital lesions associated with IgG4-RD pseudotumor.

Theoretical Insights into Bifurcated Intramolecular Dihydrogen Bonds.

Two-ring intramolecular π-electron delocalization assisted dihydrogen bonds existing in (1Z,4Z)-1,4-dipentene-3-bora-1,5-diol and its symmetrically substituted derivatives have been analysed here since the MP2/6-311++G(d,p) calculations on these systems were performed. The influence of the coexistence of two intramolecular dihydrogen bonded rings in these molecular structures on properties of intramolecular dihydrogen bonds as well as on the π-electron delocalization within these rings was investigated. The comparison with corresponding structures of typical two-ring, so-called resonance-assisted, RAHB, systems was performed. The results of calculations show that such rings' coexistence leads to the weakening of dihydrogen bonds, similarly as for the typical two-ring RAHB systems. The Quantum Theory of ''Atoms in Molecules'' (QTAIM) was also applied here to get more details about the nature of dihydrogen bonds. Correlations between dihydrogen bond strength measures and other energetic, geometrical and topological parameters were also analysed. It was found that characteristics of bond critical points as well as of ring critical points are useful to estimate the strength of intramolecular dihydrogen bonds in two-ring dihydrogen bonded systems discussed here. The Natural Bond Orbital, NBO, approach parameters are also discussed as useful ones to describe properties of dihydrogen bonded systems.

Contralateral supraorbital eyebrow approach for tuberculum sellae meningioma.

BACKGROUND: The main challenge in tuberculum sellae meningioma (TSM) resection is the safe dissection of the optic nerves, which many a times are compressed and distorted by the tumor. While intuitive, an approach from the side of predominant tumor extension makes tumor dissection from the medial surface of the ipsilateral optic nerve rather blind. We describe here a contralateral supraorbital eyebrow approach (c-SEA) to address this "blind spot." METHOD: c-SEA was performed using a 2 × 2 cm craniotomy. The patient improved after surgery and postoperative imaging confirmed the totality of the tumor resection. CONCLUSION: c-SEA can be an excellent minimally invasive option for asymmetric TSM.

Endoscopic diagnostic and surgical orbital approach in canines.

The aim of this study is to describe new diagnostic and surgical orbital approaches using video endoscopy in canines. Four different endoscopic approaches were investigated in this study of video endoscopy in cadavers: dorsal transorbital ligament approach via incision of the orbital ligament (DTOLA), dorsal subpalpebral transconjunctival approach (DSTA), ventral subpalpebral transconjunctival approach (VSTA), and transoral orbital approach (TOA). Two additional approaches, the ventral transpalpebral approach (VTA) and dorsal caudal transmuscular approach (DCTA) along with the DTOLA and DSTA were used in clinical patients. The most technically demanding approach was DTOLA; however, it provided the best visualisation of different anterior and posterior orbital structures. Visualisation of primarily the dorsal orbital wall, dorsal portion of the eye globe, and dorsal extraconal space also was achieved by DSTA. The VSTA enabled good visualisation of the ventral orbital floor and the ventral extraconal and intraconal space. In contrast, the TOA provided relatively poor visualisation of orbital structures, limited to the ventral orbital quadrant. Meanwhile, the VTA provided visualisation similar to the VSTA, while DCTA visualisation was limited to the dorsal and caudal orbital space. Orbital endoscopy is an effective and minimally invasive procedure that can be used for diagnostic and surgical orbital procedures.

Diaphragm Sellae Meningioma: Distinct Clinical, Anatomic, and Surgical Considerations: 2-Dimensional Operative Video.

Nestled in the parasellar region, surrounded by critical neurovascular structures, diaphragm sellae meningiomas although rare present distinct clinical, radiological, and surgical considerations.1-3 Consequently, they present surgical challenges that could be overcome with technical nuances. The origin of this meningioma on the diaphragm creates a distorted anatomy, which must be comprehended for the safe approach and resection. Three distinct subtypes of diaphragm sellae meningiomas are described, each with distinctive clinical presentations and surgical treatment implications.2 Type A originates from the upper leaf of diaphragm sellae pushing the stalk posteriorly. It usually presents with unilateral visual loss. Type B originates from the upper leaf of the diaphragm sellae pushing the stalk anteriorly. It presents with few visual symptoms, but memory disturbance and hypopituitarism are common. Type C originates from the inferior leaf of the diaphragm sellae (intrasellar meningioma) presenting with bitemporal hemianopsia and hypopituitarism. Recognizing these variations in this rare tumor subtype is critical to minimizing potential adverse outcomes associated with operative treatment. The cranial approach has been the recommended route for these lesions with an exception of the intrasellar type.1,3 In this article, we depict the pathological anatomy and demonstrate the surgical nuances in handling diaphragm sellae meningioma resection through a cranio-orbital approach4 in a patient who had an unsuccessful trans-sphenoidal resection attempt. The patient consented for the procedure. Image at 1:38 from Al-Mefty O, Operative Atlas of Meningiomas, © LWW, 1997, with permission. Image at 8:56 from Kinjo et al,2 Diaphragma sellae meningiomas, case reports, Neurosurgery, 1995, 36(6), 1082-1092, by permission of the Congress of Neurological Surgeons.

Orbital Surgical Guidelines: Pediatric Considerations.

Pediatric orbital and skull base surgery comprises a wide array of tumors. An understanding of the location of the lesion, nature of the disease, and surrounding anatomy is paramount to surgical planning in these small spaces. The goals of pediatric skull base surgery are to avoid injury to the surrounding structures, minimize cosmetic deformities, and remove some or all of the tumors based on anticipated pathology and biologic cost of removal. Safe surgery on many of these tumors requires an understanding of the location of the lesion relative to the optic nerve or orbit. This is particularly challenging because the dimensions of the orbital confines change continuously as one navigates from rostral to caudal. Management of these tumors may require a multidisciplinary approach including orbital surgery, neurosurgery, otolaryngology, oral maxillofacial surgery, plastic surgery, and interventional neuroradiology.

Surgical management for IgG4-related ophthalmic disease by a transcranial biopsy combined with extraorbital decompression: illustrative case.

BACKGROUND: Immunoglobulin G4-related ophthalmic disease (IgG4-ROD) accounts for 22% of Japanese lymphoproliferative orbital disease and occurs in 4%-34% of patients with IgG4-related disease, according to the largest case series published to date. Because the optic nerve mass often appears as a tumor-like lesion, it is important, although difficult, to differentiate IgG4-ROD from other orbital tumors and diseases, and biopsy is essential for diagnosis. Here, the authors describe the surgical management of an IgG4-ROD case. OBSERVATIONS: A 63-year-old man presented to the authors' hospital with proptosis and visual impairment. Ophthalmic examination revealed intraocular hypertension. IgG4-related disease with an ophthalmic lesion was suspected on the basis of a blood test and imaging studies. Transcranial biopsy with extraorbital decompression was performed. The patient's symptoms, including visual impairment, improved 3 days after operation, and his IgG4-related disease resolved after corticosteroid treatment. LESSONS: The standard treatment for IgG4-related disease is systemic corticosteroid therapy. However, this treatment should not be administered to patients with IgG4-ROD who a high risk of blindness. In this case, the authors completed a diagnostic and symptom-relieving transcranial biopsy without affecting the patient's aesthetic characteristics. This is the first study, to our knowledge, to report extraorbital decompression via a transcranial approach as a surgical option for IgG4-ROD.

Surgery around the Orbit: How to Select an Approach.

Orbital region pathologies may be safely and effectively treated through a various number of approaches. As the concept of "outcome" and minimally invasive surgery keeps gaining popularity in neurosurgery, these approaches-each with specific indications and limitations-together provide the best surgical options.

The Lateral Orbitotomy Approach for Intraorbital Lesions.

The lateral orbitotomy approach (LOA) was first described by Kronlein in 1888 and has since been subject to many modifications and variations. When considering orbital approaches, the location of the pathology is often more important in decision making than the type of pathology. The LOA is best suited for access to intraconal and extraconal lesions lateral to the optic nerve. Pathologies treated via the LOA include primary orbital tumors, extraorbital tumors with local extension into the orbit, and distantly metastatic lesions to the orbit. These all often initially manifest with vision loss, oculomotor deficits, or proptosis. The expertise of a multidisciplinary team is needed to execute safe and effective treatment. Collaboration between many specialties may be required, including ophthalmology, neurosurgery, otolaryngology, plastic surgery, oncology, and anesthesiology. The modern technique involves either a lateral canthotomy or eyelid crease incision with removal of the lateral orbital wall. It affords many advantages over a pterional craniotomy, primarily a lower approach morbidity and superior cosmetic outcomes. Reconstruction is fairly simple and the rate of complications-vision loss and extraocular muscle palsy-are low and infrequently permanent. Deep orbital apex location and intracranial extension have traditionally been considered limitations of this approach. However, with increased surgeon comfort, modern technique, and the adoption of endoscopy, these limits have expanded to even include primarily intracranial pathologies. This review details the LOA, including the general technique, its indications and limitations, reconstruction considerations, complications, and recent data from case series. The focus is on microscopic access to intraorbital lesions.

Mini Fronto-Orbital Approach: "Window Opening" Towards the Superomedial Orbit - A Virtual Reality-Planned Anatomic Study.

BACKGROUND: Surgical approaches to the orbit are challenging and require combined multispecialist skills. Considering its increasing relevance in neurosurgical practice, keyhole surgery could be also applied to this field. However, mastering a minimally invasive approach necessitates an extended learning curve. For this reason, virtual reality (VR) can be effectively used for planning and training in this demanding surgical technique. OBJECTIVE: To validate the mini fronto-orbital (mFO) approach to the superomedial orbit, using VR planning and specimen dissections, conjugating the principles of skull base and keyhole neurosurgery. METHODS: Three-dimensional measurements were performed thanks to Surgical Theater (Surgical Theater© LLC), and then, simulated craniotomies were implemented on cadaver specimens. RESULTS: The mFO approach affords optimal exposure and operability in the target area and reduced risks of surrounding normal tissue injuries. The eyebrow skin incision, the minimal soft-tissue retraction, the limited temporalis muscle dissection and the single-piece craniotomy, as planned with VR, are the key elements of this minimally invasive approach. Furthermore, the "window-opening" cotton-tip intraorbital dissection technique, based on widening surgical corridors between neuromuscular bundles, provides a safe orientation and a deep access inside the orbit, thereby significantly limiting the risk of jeopardizing neurovascular structures. CONCLUSION: The mFO approach associated to the window-opening dissection technique can be considered safe, effective, suitable, and convenient for treating lesions located in the superomedial orbital aspect, up to the orbital apex.

Pure Endoscopic Lateral Orbitotomy Approach to the Cavernous Sinus, Posterior, and Infratemporal Fossae: Anatomic Study.

Objective The aim of this anatomic study is to describe a fully endoscopic lateral orbitotomy extradural approach to the cavernous sinus, posterior, and infratemporal fossae. Material and Methods Three prefixed latex-injected head specimens (six orbital exposures) were used in the study. Before and after dissection, a computed tomography scan was performed on each cadaver head and a neuronavigation system was used to guide the approach. The extent of bone removal and the area of exposure of the targeted corridor were evaluated with the aid of OsiriX software (Pixmeo, Bernex, Switzerland). Results The lateral orbital approach offers four main endoscopic extradural routes: the anteromedial, posteromedial, posterior, and inferior. The anteromedial route allows a direct route to the optic canal by removal of the anterior clinoid process, whereas the posteromedial route allows for exposure of the lateral wall of the cavernous sinus. The posterior route is targeted to Meckel's cave and provides access to the posterior cranial fossa by exposure and drilling of the petrous apex, whereas the inferior route gives access to the pterygopalatine and infratemporal fossae by drilling the floor of the middle cranial fossa and the bone between the second and third branches of the trigeminal nerve. Conclusion The lateral orbitotomy endoscopic approach provides direct access to the cavernous sinus, posterior, and infratemporal fossae. Advantages of the approach include a favorable angle of attack, minimal brain retraction, and the possibility of dissection within the two dural layers of the cavernous sinus without entering its neurovascular compartment.

Laterocaudal approach to the inferior rim of the orbit.

PURPOSE: Fractures of the orbital floor and orbital rim are frequently treated in maxillofacial departments. Various approaches to the orbital floor are described in the literature. We present an investigation of a modified subciliary approach (laterocaudal approach) with respect to its feasibility and clinical outcome. MATERIALS AND METHODS: Our retrospective study investigated 130 well-documented cases of patients with orbital floor fractures who received surgical reconstruction using a laterocaudal approach, and compared the results with the current literature, with a focus on subciliary and transconjunctival approaches. RESULTS: 111 patients (85.4%) presented a Vancouver scar scale (VSS) of 0.14 patients (10.8%) had a VSS score of 1. No patients had a VSS of 2. Just five patients (3.8%) had a slight ectropium and therefore a VSS score of 3. CONCLUSION: The laterocaudal approach can be safely performed and presents advantages over comparable techniques such as the subciliary and transconjunctival approaches if performed correctly.

Supraorbital approach through eyebrow skin incision for aneurysm clipping: how I do it.

BACKGROUND: Surgery has been in a huge development where the aim is to achieve same or better results with less complication in a less invasive way; these minimal approaches can be applied in a very safe way to aneurysmal neurosurgery. METHOD: Images are studied to optimize the patient positioning and the surgical roadmap. After the positioning, the skin incision, craniotomy, and dura incision are performed and intradural lesion is reached. A watertight closure is performed under the microscope. CONCLUSION: The keyhole approach requires some adaption from the side of the surgeon and can be performed only in cases envisioned to have no increased risk for the patient.

Supraorbital vs Endo-Orbital Routes to the Lateral Skull Base: A Quantitative and Qualitative Anatomic Study.

BACKGROUND: Various extensions of the supraorbital approach reach the lateral and parasellar middle cranial fossa regions by removing the orbital rim and greater/lesser sphenoid wings. Recent proposals of a purely endoscopic ventral transorbital pathway to these regions heighten the need to compare these surgical windows. OBJECTIVE: To detail the lateral and parasellar middle cranial fossa regions and quantify exposures by 2 surgical windows (transcranial and transorbital) through anatomic study. METHODS: In 5 cadaveric specimens (10 sides), dissections consisted of 3 stages: stage 1 began with the supraorbital approach via the eyebrow; stage 2, endo-orbital approach via the superior eyelid, continued with removal of lesser and greater sphenoid wings; and stage 3, extended supraorbital, re-evaluated the gains of stage 2 from the perspective of stage 1. Operative working areas were quantified in Sylvian, anterolateral temporal, and parasellar regions; bone removal volumes were measured at each stage (nonpaired Student t-test). RESULTS: Visualization into the anterolateral temporal and Sylvian areas, though varied in perspective, were comparable with either eyelid or transcranial routes. Compared with transcranial views through a supraorbital window, the eyelid approach significantly increased exposure in the parasellar region with wider angle of attack (P < .01) and achieved comparable bone removal volumes. CONCLUSION: Stage 2's unique anatomic view of the lateral and parasellar middle cranial fossa regions paves the way for possible surgical application to select pathologies typically treated via transcranial approaches. Disadvantages may be the surgeon's unfamiliarity with the anatomy of this purely endoscopic, ventral route and difficulties of dural and orbital repair.

Chemosis as complication in transconjunctival approach for orbital trauma.

The aim of this report was to discuss a complication resulting from a transconjunctival approach to treating an orbital fracture. A 30-year-old male patient presented with a fracture to the zygomatic orbital complex. He was treated with transconjunctival conventional surgical treatment. Two days after surgical treatment, the patient presented with secondary chemosis which was initially slight and then subsequently worsened. The clinical situation was managed with topical and systemic corticosteroids and resolved within one postoperative month. Two-year follow-up showed ptosis of the upper eyelid and limited infraversion in the affected eye. This unusual complication associated with an orbital trauma was resolved with minor functional alterations, although the consequences observed after 2 years were not completely satisfactory.

Chemosis as complication in transconjunctival approach for orbital trauma

The aim of this report was to discuss a complication resulting from a transconjunctival approach to treating an orbital fracture. A 30-year-old male patient presented with a fracture to the zygomatic orbital complex. He was treated with transconjunctival conventional surgical treatment. Two days after surgical treatment, the patient presented with secondary chemosis which was initially slight and then subsequently worsened. The clinical situation was managed with topical and systemic corticosteroids and resolved within one postoperative month. Two-year follow-up showed ptosis of the upper eyelid and limited infraversion in the affected eye. This unusual complication associated with an orbital trauma was resolved with minor functional alterations, although the consequences observed after 2 years were not completely satisfactory.

Orbital Approaches for Treatment of Carotid Cavernous Fistulas: A Systematic Review.

BACKGROUND: Carotid cavernous fistulas (CCFs) are abnormal connections between the carotid arteries and the cavernous sinus. CCFs often present with double vision, reduced visual acuity, and conjunctivitis. Deteriorating ocular symptoms caused by abnormal fistula drainage can cause permanent blindness, and so urgent interventional treatment is necessary. Transvenous embolization of the fistula is the primary treatment option for most patients with symptomatic CCFs. Orbital approaches are considered to be risky compared with the traditional approach via the inferior petrosal sinus and are thus used as a secondary option. These approaches include embolization via the superior ophthalmic vein, inferior ophthalmic vein, and medial ophthalmic vein and direct transorbital puncture. This study aims to assess the merits and risks of orbital approaches in transvenous embolization of CCFs. METHODS: A systematic review of 30 studies assessing the radiographic and clinical outcomes of this approach was conducted. Outcomes of interest included successful fistula closure, postoperative improvement of ocular symptoms, and complications from the procedure. Weighted averages were calculated for all outcomes. RESULTS: Transvenous embolization via an orbital approach had a high success rate (89.9%). Improvement in visual acuity and proptosis was found in 93.4% and 88.1% of patients, respectively. There were no major complications. Minor complications found included subconjunctival hemorrhage (n = 4), intraorbital hemorrhage (n = 1), eyelid hematoma (n = 1), and foreign-body granuloma (n = 3). CONCLUSIONS: All orbital approaches for transvenous embolization of CCFs are effective and safe.

Bicoronal frontobasal approach with a limited, midline orbital bar osteotomy - a technical note.

The frontobasal approach remains a workhorse for removing large olfactory groove meningiomas. Removal of the orbital bar in addition to standard bifrontal craniotomy allows for additional basal exposure, minimising brain retraction and allowing early and direct access to both the vascular supply and dural origin of this tumour. Here, we describe a simple yet effective modification to the standard orbital bar osteotomy. It has the benefit of being simpler and faster with improved cosmesis compared with an osteotomy of the entire orbital bar. It also has the advantage of not requiring manipulation of the supraorbital nerves or intraorbital or periorbital dissection.