Endoscopic transorbital approach in children: surgical technique and early results.

OBJECTIVE: In this study, the authors aimed to describe the endoscopic transorbital approach (ETOA) in children. METHODS: Six pediatric patients (2 girls and 4 boys) underwent the ETOA for paramedian skull base lesions at a single institution between September 2016 and February 2023. RESULTS: The median age at the time of surgery was 7.5 (range 4-18) years. The median follow-up period was 33 (range 9-60) months. In this series, the ETOA level of difficulty included stage 1 (n = 2, 33.3%), stage 3 (n = 3, 50%), and stage 5 (n = 1, 16.7%). The ETOA was performed for tumor resection in 4 cases; the final pathology consisted of fibrous dysplasia, pilocytic astrocytoma, metastatic neuroblastoma, and choroid plexus papilloma. The procedure was also performed for repair of a petrous apex meningocele and for lateral orbital wall decompression of traumatic lateral rectus muscle entrapment. One patient experienced a transient cranial nerve III palsy after the procedure. There were no operative deaths in this series. CONCLUSIONS: In select cases, the ETOA can be considered a minimally invasive alternative for conventional skull base approaches in the armamentarium of pediatric skull base surgery. Further investigation and the accumulation of experience are warranted in the future to enhance the efficacy and applicability of the ETOA in pediatric patients.

Clinical outcomes and complications of eyelid versus eyebrow approaches to supraorbital craniotomy: systematic review and indirect meta-analysis.

OBJECTIVE: Eyebrow supraorbital craniotomy is a versatile keyhole technique for treating intracranial pathologies. The eyelid supraorbital approach, an alternative approach to an eyebrow supraorbital craniotomy, has not been widely adopted among most neurosurgeons. The purpose of this systematic review and meta-analysis was to perform a pooled analysis of the complications of eyebrow or eyelid approaches for the treatment of aneurysms, meningiomas, and orbital tumors. METHODS: A systematic review of the literature in the PubMed, Embase, and Cochrane Review databases was conducted for identifying relevant literature using keywords such as "supraorbital," "eyelid," "eyebrow," "tumor," and "aneurysm." Eyebrow supraorbital craniotomies with or without orbitotomies and eyelid supraorbital craniotomies with orbitotomies for the treatment of orbital tumors, intracranial meningiomas, and aneurysms were selected. The primary outcomes were overall complications, cosmetic complications, and residual aneurysms and tumors. Secondary outcomes included five complication domains: orbital, wound-related, scalp or facial, neurological, and other complications. RESULTS: One hundred three articles were included in the synthesis. The pooled numbers of patients in the eyebrow and eyelid groups were 4689 and 358, respectively. No differences were found in overall complications or cosmetic complications between the eyebrow and eyelid groups. The proportion of residuals in the eyelid group (11.21%, effect size [ES] 0.26, 95% CI 0.12-0.41) was significantly higher (p < 0.05) than that in the eyebrow group (6.17%, ES 0.10, 95% CI 0.08-0.13). A subgroup analysis demonstrated significantly higher incidences of orbital, wound-related, and scalp or facial complications in the eyelid group (p < 0.05), but higher other complications in the eyebrow group. Performing an orbitotomy substantially increased the complication risk. CONCLUSIONS: This is the first meta-analysis that quantitatively compared complications of eyebrow versus eyelid approaches to supraorbital craniotomy. This study found similar overall complication rates but higher rates of selected complication domains in the eyelid group. The literature is limited by a high degree of variability in the reported outcomes.

Anterolateral keyhole transorbital routes to the skull base: a comparative anatomical study.

OBJECTIVE: Although keyhole transorbital approaches are gaining traction, their indications have not been adequately studied comparatively. In this study the authors have defined them also as transwing approaches-meaning that they use the different facies of the sphenoid wing for cranial entry-and sought to compare the four major ones: 1) lateral orbitocraniotomy through a lateral canthal incision (LatOrb); 2) modified orbitozygomatic approach through a palpebral incision (ModOzPalp); 3) modified orbitozygomatic approach through an eyebrow incision (ModOzEyB); and 4) supraorbital craniotomy through an eyebrow incision (SupraOrb), coupled with its expanded version (SupraTransOrb). METHODS: Cadaveric dissections were performed at the neuroanatomy lab. To delineate the skull base exposure, four formalin-fixed heads were used, with two sides dedicated to each approach. The outer limits were assessed via image guidance and were mapped and illustrated accordingly. A fifth head was dissected purely endoscopically, just to facilitate an overview of the transwing concept. Qualitative features were also rigorously examined. RESULTS: The LatOrb proves to be more versatile in the middle cranial fossa (MCF), whereas the anterior cranial fossa (ACF) exposure is limited to a small area above the sphenoid ridge. An anterior clinoidectomy is possible; however, the exposure of the roof of the optic canal is suboptimal. The ModOzPalp adequately exposes both the ACF and MCF. Its lateral trajectory allows the inferior to superior view, yet there is restricted access to the medial anterior skull base (olfactory groove). The ModOzEyB also provides extensive exposure of the ACF and MCF, but has a more superior to inferior trajectory compared to the ModOzPalp, making it more appropriate for pathology reaching the medial anterior skull base or even the contralateral side. The anterior clinoidectomy is performed with improved visualization of the optic canal. The SupraOrb provides mainly anterior cranial base exposure, with minimal middle fossa. An anterior clinoidectomy can be performed, but without any direct observation of the superior orbital fissure. Some MCF access can be accomplished if the lateral sphenoid wing is drilled inferiorly, leading to its highly versatile variant, the SupraTransOrb. CONCLUSIONS: All the aforementioned approaches use the sphenoid wing as skull base corridor from a specific orientation point; hence these are designated as transwing approaches. Their peculiarities mandate careful case selection for the effective and safe completion of the surgical goals.

360° around the orbit: key surgical anatomy of the microsurgical and endoscopic cranio-orbital and orbitocranial approaches.

OBJECTIVE: Several pathologies either invade or arise within the orbit. These include meningiomas, schwannomas, and cavernous hemangiomas among others. Although several studies describing various approaches to the orbit are available, no study describes all cranio-orbital and orbitocranial approaches with clear, surgically oriented anatomical descriptions. As such, this study aimed to provide a comprehensive guide to the microsurgical and endoscopic approaches to and through the orbit. METHODS: Six formalin-fixed, latex-injected cadaveric head specimens were dissected in the surgical anatomy laboratory at the authors' institution. In each specimen, the following approaches were modularly performed: endoscopic transorbital approaches (ETOAs), including a lateral transorbital approach and a superior eyelid crease approach; endoscopic endonasal approaches (EEAs), including those to the medial orbit and optic canal; and transcranial approaches, including a supraorbital approach, a fronto-orbital approach, and a 3-piece orbito-zygomatic approach. Each pertinent step was 3D photograph-documented with macroscopic and endoscopic techniques as previously described. RESULTS: Endoscopic endonasal approaches to the orbit afforded excellent access to the medial orbit and medial optic canal. Regarding ETOAs, the lateral transorbital approach afforded excellent access to the floor of the middle fossa and, once the lateral orbital rim was removed, the cavernous sinus could be dissected and the petrous apex drilled. The superior eyelid approach provides excellent access to the anterior cranial fossa just superior to the orbit, as well as the dura of the lesser wing of the sphenoid. Craniotomy-based approaches provided excellent access to the anterior and middle cranial fossa and the cavernous sinus, except the supraorbital approach had limited access to the middle fossa. CONCLUSIONS: This study outlines the essential surgical steps for major cranio-orbital and orbitocranial approaches. Endoscopic endonasal approaches offer direct medial access, potentially providing bilateral exposure to optic canals. ETOAs serve as both orbital access and as a corridor to surrounding regions. Cranio-orbital approaches follow a lateral-to-medial, superior-to-inferior trajectory, progressively allowing removal of protective bony structures for proportional orbit access.

360 Degrees Endoscopic Access to and Through the Orbit.

The treatment of pathologies located within and surrounding the orbit poses considerable surgical challenges, due to the intricate presence of critical neurovascular structures in such deep, confined spaces. Historically, transcranial and craniofacial approaches have been widely employed to deal with orbital pathologies. However, recent decades have witnessed the emergence of minimally invasive techniques aimed at reducing morbidity. Among these techniques are the endoscopic endonasal approach and the subsequently developed endoscopic transorbital approach (ETOA), encompassing both endonasal and transpalpebral approaches. These innovative methods not only facilitate the management of intraorbital lesions but also offer access to deep-seated lesions within the anterior, middle, and posterior cranial fossa via specific transorbital and endonasal corridors. Contemporary research indicates that ETOAs have demonstrated exceptional outcomes in terms of morbidity rates, cosmetic results, and complication rates. This study aims to provide a comprehensive description of endoscopic-assisted techniques that enable a 360° access to the orbit and its surrounding regions. The investigation will delve into indications, advantages, and limitations associated with different approaches, while also drawing comparisons between endoscopic approaches and traditional microsurgical transcranial approaches.

Primary intraorbital inflammatory lumpy lesion: A rare case report.

RATIONALE: Eosinophilic angiocentric fibrosis (EAF) is considered to be a kind of benign IgG4-related disease, and it is more often found in the nasal cavity. We present a pretty rare case of orbital EAF that is unlike any other reported case for this case is an IgG4 negative orbital EAF and successfully treated by the fronto orbitozygomatic approach surgery. PATIENT CONCERNS: This is a 68-year-old man from a rural area of Inner Mongolia Autonomous Region, went to our hospital for a 2-month history of vision loss with a local hospital orbital computer tomography which showed that there was a lesion in his left orbit. The inspection of the patient revealed that the patient left eye was protruding outward and the left eyelid unable to complete open or close. And his left eyeball movement had difficulty in all directions. Postoperative pathology diagnosed that this was a case of IgG4-negative EAF case. DIAGNOSES: Orbital EAF. INTERVENTIONS: Surgical radical resection and postoperative glucocorticoid therapy. OUTCOMES: After surgery, the left eye vision of this patient increased to 0.6 tested in the standard logarithmic visual acuity chart. And his left eyeball movement dysfunction and eyeball outward protruding get a partially relief. LESSONS: EAF occurring in the orbit is a very rare disease and immunohistochemical results of EAF can be IgG4 negative.

Factors affecting anophthalmic socket reconstruction outcomes using autologous oral mucosal graft.

BACKGROUND: Limited studies have reported surgical outcomes that are defined by strict criteria following grade 2 or 3 socket reconstruction using an oral mucosal graft (OMG). We aimed to determine factors influencing surgical outcomes of anophthalmic socket reconstruction using OMG in patients with grade 2 or 3 socket contractures. METHODS: Thirty-seven patients who underwent socket reconstruction with autologous OMG between January 2007 and December 2017 were retrospectively analyzed. The successful outcome was defined as an eye prosthesis wearing without experiencing displacement and the absence of any re-operations or additional surgeries following socket reconstruction. Factors affecting surgical outcomes were identified using multivariate analysis. RESULTS: A total of 15 male and 22 female patients (mean age: 40.2 ± 17.2 years) were included. The median duration of socket contracture was 21.5 years. Grade 2 and 3 socket contractures, based on Tawfik's classification, were reported in 20 and 17 patients, respectively. Twenty-eight and eight patients underwent socket reconstruction using OMG alone and OMG combined with a hard palate graft, respectively. The success rates of grades 2 and 3 socket contracture reconstruction were 80.0% and 52.9%, respectively. Multivariate analysis demonstrated that only grade 3 contractures were predictive of worse outcomes. At the final visit (mean follow-up: 6.3 years), 34 patients (91.9%) could wear their eye prostheses. CONCLUSIONS: Socket reconstruction using autologous OMG can provide acceptable results in grade 2 and 3 contractures; however, satisfactory results were more significantly reported in grade 2 than in grade 3 contractures.

Adjunctive transseptal corridor: Technique for endoscopic resection of orbital tumor.

The transnasal endoscopic approach is increasingly used for resection of tumors that are located inferiorly and medially within the orbit. However, this usually requires multiple-handed manipulations, which demand a second corridor for an assistant. Here, we introduce a simple transseptal corridor from the contra-nare, to facilitate assistant instrument maneuverability. This simple, minimally invasive skill greatly improves operation efficiency and deserves greater attention in endoscopic orbital surgery.

Initial implementation of surgical guide design utilizing digital medicine for lateral orbital decompression surgery.

This study aimed to assess the feasibility of utilizing a surgical guide, designed through digital medical technology, in lateral orbital decompression surgery. METHODS: In total, 18 patients with thyroid-associated ophthalmopathy (TAO), who underwent orbital balance decompression surgery at the Affiliated Eye Hospital of Nanchang University between September 2018 and August 2022, were included. Orbital CT scanning was performed on all patients with TAO, and Mimics 21.0 software was used to reconstruct a three-dimensional model of the orbit based on the CT data. The osteotomy guide plate for lateral orbital decompression surgery was designed using 3-matic 13.0 software, adhering to the criteria of surgical effectiveness and safety. The surgical positioning guide was designed using Geomagic Wrap 21.0. Once printed, the surgical guide was sterilized with low-temperature plasma and applied during surgery. Of the nine patients treated using a surgical navigation system, three cases experienced cerebrospinal fluid leakage complications during the procedure, and two exhibited inadequate bone removal along the lateral wall. In contrast, among the nine patients treated with surgical guides, no intraoperative cerebrospinal fluid leakage or evidence of insufficient lateral wall bone removal was observed, highlighting a statistically significant distinction between the two cohorts (p = 0.046). Postoperative improvements were notable in best-corrected visual acuity (BCVA) and exophthalmos for patients afflicted with extremely severe TAO. The surgical guide, designed with digital medical technology, has been shown to be an effective and secure auxiliary tool in lateral orbital decompression surgery. It not only aids in reducing the incidence of intraoperative complications, but also enhances the accuracy and safety of surgery. These improvements offer robust support for continued exploration in this field within clinical practice.

Exo- and endoscopic lateral orbital wall approach for the medial temporal lobe glioma: how I do it.

BACKGROUND: The endoscopic transorbital approach provides a direct access to the medial temporal lobe (MTL). However, when excising a highly vascular tumour, a wider access route that enables the concurrent use of standard neurosurgical instruments with both hands is preferable. METHOD: We described the concept and technique of the lateral orbital wall approach (LOWA), which comprises orbitotomy and mini-craniotomy to treat MTL lesions using an exoscope and endoscope. CONCLUSION: The LOWA provides a safe and natural surgical corridor to the MTL and enables 2- or 3-hand surgery. Hence, LOWA can potentially improve safety and efficiency to treat MTL lesions.

Clinical and radiographic assessment of patient-specific transantral reconstruction of orbital floor fractures: A case series.

To clinically and radiographically evaluate patient-specific titanium meshes via a trans-antral approach for correction of enophthalmos and orbital volume in patients with recent unilateral orbital floor fracture. Seven patients with unilateral orbital floor fractures received patient-specific titanium meshes that were designed based on a mirror-image of the contralateral intact orbit. The patient-specific implants (PSIs) were inserted via a trans-antral approach without endoscopic assistance. The patients were evaluated clinically for signs of diplopia and restricted gaze as well as radiographically for enophthalmos and orbital volume correction. Diplopia was totally resolved in two of the three patients who reported diplopia in the upward gaze. Whereas enophthalmos significantly improved in all but two patients, with a mean value of 0.2229 mm postoperatively compared to 0.9914 mm preoperatively. CT scans showed excellent adaptation of the PSIs to the orbital floor with a mean reduction of the orbital volume from 29.59 cc to 27.21 cc, a mean of 0.6% smaller than the intact orbit. It can be concluded that the proposed PSI can offer good reconstruction of the orbital floor through an isolated intraoral transantral approach with minimal complications. It could of special benefit in extensive orbital floor fractures.

Customized orbital implant versus 3D preformed titanium mesh for orbital fracture repair: A retrospective comparative analysis of orbital reconstruction accuracy.

This study aimed to compare the accuracy of inferomedial orbital fracture restoration using customized orbital implant versus 3D preformed titanium mesh. Patients were divided into two groups. Group 1 underwent surgery with customized orbital implants and intraoperative navigation, while group 2 was treated using 3D preformed titanium meshes with preoperative virtual surgical planning (VSP) and intraoperative navigation. Reconstruction accuracy was assessed by: (1) comparing the postoperative reconstruction mesh position with the preoperative VSP; and (2) measuring the difference between the reconstructed and unaffected orbital volume. Pre- and postoperative diplopia and enophthalmos were also evaluated. Fifty-two patients were enrolled (25 in group 1 vs 27 in group 2). The mean difference between final plate position and ideal digital plan was 0.62 mm (SD = 0.235) in group 1 and 0.69 mm (SD = 0.246) in group 2, with no statistical difference between the groups (p = 0.282). The mean volume differences between the reconstructed and unaffected orbits were 0.95 ml and 1.02 ml in group 1 and group 2, respectively, with no significant difference between the groups (p = 0.860). Overall clinical improvements, as well as complications, were similar. 3D preformed titanium meshes can reconstruct inferomedial fractures with the same accuracy as customized implants. Therefore, in clinical practice, it is recommended to use 3D preformed meshes for this type of fracture due to their excellent results and the potential for reducing time and costs.

Comparison of patient specific implant reconstruction vs conventional titanium mesh reconstruction of orbital fractures using a novel method.

To compare the reconstruction of orbital fractures using patient-specific implants (PSI) and conventional pre-formed titanium mesh; to develop a method of three-dimensional (3D) superimposition and analysis of the reconstructed orbits; and to present the pitfalls in 3D planning of orbital PSI and how to avoid them. This was a retrospective study of patients with orbital fractures who were treated in our institution between the years 2022 and 2023 using PSI or conservative prefabricated titanium mesh. Three different methods for virtual reconstruction of orbital fractures were used and are detailed with advantages, disadvantages and indications. Data acquired included age, gender, method of reconstruction, functional outcomes and aesthetic outcomes. 3D analysis for accuracy of reconstruction was performed. A total of 23 patients were included; 12 were treated using PSI and 11 using prefabricated titanium meshes. There were 8 male and 4 female patients in the PSI group comparted to 5 and 6 in the prefabricated group. All three virtual methods for reconstruction were used successfully, each with the proper indications. When comparing PSI reconstruction to conventional mesh, a significant difference in accuracy was observed; PSI cases showed an inaccuracy of 0.58 mm compared to 1.54 mm with the conventional method. Complications are presented, and tips for avoiding them are detailed. Three different methods for virtual reconstruction were used successfully; automated computerized reconstruction is used for small defects, repositioning is the superior method for non-comminuted cases while mirroring is the method of choice in comminuted fractures. 3D analysis can be performed using a novel method detailed in this report. PSI reconstruction showed superior results, indicating it should be the method of choice when possible. Pitfalls are presented and approaches to prevent them are discussed. Orbital reconstruction is a very important entity in maxillofacial surgery with crucial functional and esthetical implications, and one should use virtual planning and PSI implants, as they significantly improve outcomes.

Epidemiological analysis of patients with isolated blowout fractures of orbital floor: Correlation between demographic characteristics and fracture area.

Isolated orbital floor fractures are more frequent due to low bone thickness (2 mm). The aim of this study was to conduct a retrospective epidemiological analysis on these fractures, investigating demographic variables and fractures' features and their statistical correlation. A total of 120 patients with isolated orbital floor fracture, admitted at the Maxillofacial Surgery Unit of University of Naples Federico II, from 2010 to 2022 were enrolled in the study. Patients were evaluated for age, sex, smoke, comorbidities, post-traumatic clinical manifestation,s and defect side and size. Statistical analysis was conducted using the Pearson regression coefficient (r). The fractures were more frequent in men (male:female 2.2:1) because of road accidents (30% of cases). The average age was 48 years. Enophthalmos, diplopia and ocular motility anomalies were observed in 31%, 23% and 21% of cases, respectively. Statistical analysis revealed that age was related to fracture area; in particular, older patients showed larger fractures (p < 0.001). Interpersonal violence and traffic accidents were related to younger age (p < 0.001). Data analysis revealed that isolated orbital floor fractures are more frequent in young men (<40 years) because of road accidents or interpersonal violence. There is a statistical correlation between fracture area and patient age; in particular, older age corresponds to larger defects.

Delayed onset enophthalmos and hypoglobus mimicking silent sinus syndrome following midface trauma.

Craniomaxillofacial trauma is primarily diagnosed and managed by oral and maxillofacial surgeons. Among the cases encountered, midface fractures involving orbital walls are highly prevalent. In these fractures, involvement of the orbital walls, particularly floor of the orbit, can lead to considerable aesthetic and functional limitations. From a maxillofacial perspective, indications for surgical repair of orbital floor encompass marked decrease in ocular motility, fracture affecting more than 50% of surface area, an increase in orbital volume exceeding 18% and enophthalmos greater than 2 mm. In the absence of these discernible signs, surgical intervention is not generally indicated. However, in this case, an early adolescent with a history of midface trauma and minimal orbital floor fracture 8 months earlier presented with progressively delayed onset enophthalmos and hypoglobus closely resembling features of silent sinus syndrome. The enophthalmos and hypoglobus were corrected by placing custom-made non-resorbable high-density polyethylene implant in the orbital floor. Postoperative follow-up demonstrated aesthetically and functionally satisfactory outcomes.

Nasal monobloc osteotomy for correction of late nasal and orbital asymmetry of unicoronal synostosis: A morphometric and outcomes study.

BACKGROUND: Craniofacial asymmetry associated with unicoronal synostosis (UCS) may persist into the teenage years despite surgery in infancy. This study evaluated outcomes following a nasal monobloc procedure by mobilizing a united nasomaxillary and bilateral medial orbital segment of bone (nasal monobloc) to perform corrective translational and rotational movement for secondary correction of residual nasal-orbital asymmetry associated with UCS. METHODS: A retrospective review of all UCS patients treated with nasal monobloc at our institution was performed. Demographic information was recorded, and pre- and postoperative 2D imaging was used for morphometric outcome analysis. Outcomes and complications were tabulated. RESULTS: The study included 14 patients (5 males, 9 females; mean age 14.6 years; range 9.6 to 22.5 years; mean follow-up 70.6 months range 12 to 132 months). Ancillary procedures (scar revision, forehead/orbital contouring, MEDPOR® augmentation) were performed in all patients at the time of the nasal monobloc. One patient underwent a repeat procedure 6 years later following technique modification. Additionally, another patient experienced late overgrowth of the frontal sinus with forehead asymmetry. The morphometric analysis demonstrated significant (p < 0.05) pre-op to post-op improvements in naso-orbital asymmetry, as demonstrated by horizontal orbital aperture ratio (0.88 vs 0.99), midline to exocanthion ratio (0.91 vs 0.98), orbital index ratio (1.15 vs 1.01), and midline discrepancy (7.1 degrees vs 2.7 degrees). CONCLUSION: Nasal monobloc osteotomy provides a reasonable surgical treatment to improve both the nasal and orbital asymmetries associated with unicoronal synostosis, including frontal nasal deviation, basal nasal deviation, and orbital aperture asymmetry. It is important to note that confounding anatomic variables such as globe dystopia, strabismus, and scleral show may affect the perception of orbital symmetry.

Semi-supervised segmentation of orbit in CT images with paired copy-paste strategy.

The segmentation of the orbit in computed tomography (CT) images plays a crucial role in facilitating the quantitative analysis of orbital decompression surgery for patients with Thyroid-associated Ophthalmopathy (TAO). However, the task of orbit segmentation, particularly in postoperative images, remains challenging due to the significant shape variation and limited amount of labeled data. In this paper, we present a two-stage semi-supervised framework for the automatic segmentation of the orbit in both preoperative and postoperative images, which consists of a pseudo-label generation stage and a semi-supervised segmentation stage. A Paired Copy-Paste strategy is concurrently introduced to proficiently amalgamate features extracted from both preoperative and postoperative images, thereby augmenting the network discriminative capability in discerning changes within orbital boundaries. More specifically, we employ a random cropping technique to transfer regions from labeled preoperative images (foreground) onto unlabeled postoperative images (background), as well as unlabeled preoperative images (foreground) onto labeled postoperative images (background). It is imperative to acknowledge that every set of preoperative and postoperative images belongs to the identical patient. The semi-supervised segmentation network (stage 2) utilizes a combination of mixed supervisory signals from pseudo labels (stage 1) and ground truth to process the two mixed images. The training and testing of the proposed method have been conducted on the CT dataset obtained from the Eye Hospital of Wenzhou Medical University. The experimental results demonstrate that the proposed method achieves a mean Dice similarity coefficient (DSC) of 91.92% with only 5% labeled data, surpassing the performance of the current state-of-the-art method by 2.4%.

Endoscopic transorbital decompression for traumatic superior orbital fissure syndrome: from cadaveric study to clinical application.

PURPOSE: The endoscopic endonasal approach (EEA) is a minimally invasive and promising modality for treating traumatic superior orbital fissure (SOF) syndrome (tSOFS). Recently, the endoscopic transorbital approach (ETOA) has been considered an alternative method for reaching the anterolateral skull base. This study accessed the practicality of using the ETOA to treat SOF decompression using both cadaveric dissection and clinical application. METHODS: Bilateral anatomic dissections were performed on four adult cadaveric heads using the ETOA and EEA to address SOF decompression. The ETOA procedure for SOF decompression is described, and the extent of SOF decompression was compared between the ETOA and EEA. The clinical feasibility of the ETOA for treating SOF decompression was performed in two patients diagnosed with tSOFS. RESULTS: ETOA allowed for decompression over the lateral aspect of the SOF, from the meningo-orbital band superolaterally to the maxillary strut inferomedially. By contrast, the EEA allowed for decompression over the medial aspect of the SOF, from the lateral opticocarotid recess superiorly to the maxillary strut inferiorly. In both patients treated using the ETOA and SOF decompression, the severity of ophthalmoplegia got obvious improvement. CONCLUSIONS: Based on the cadaveric findings, ETOA provided a feasible access pathway for SOF decompression with reliable outcomes, and our patients confirmed the clinical efficacy of the ETOA for managing tSOFS.

Postoperative magnetic resonance imaging of the inferior oblique muscle.

No previous imaging study has described the appearance of the inferior oblique muscle after surgery. It is unknown whether findings signifying prior myectomy or recession are recognizable on magnetic resonance (MR) imaging and how they might differ for the two procedures. After myectomy via a temporal approach, the cauterized muscle stump retracts into the medial orbit. How far it retracts and whether it reattaches to the globe remains unclear. To address these issues, orbital MR images were reviewed in 5 patients who had previously undergone inferior oblique myectomy or recession. In each case, the operated muscle exhibited subtle but telltale features, when compared with the normal, fellow inferior oblique. After myectomy, the inferior oblique still terminated lateral to the inferior rectus muscle and appeared closely apposed to the globe, although not necessarily attached to the sclera.