Deep Lateral Orbital Wall Decompression Research Articles

Superior orbital fissure syndrome after deep lateral orbital wall decompression in Graves’ ophthalmopathy

ABSTRACT Purpose The superior orbital fissure contains cranial nerves III, IV, VI, and V1 with their three branches: frontal, lacrimal, and nasociliary. Superior orbital fissure syndrome (SOFS) is rare and can occur as a result of compression of these nerves due to trauma, bleeding, or inflammation in the retrobulbar space, but no cases of SOFS after deep lateral orbital wall decompression (DLOWD) have been reported. The aim of this paper is to describe this pathology, its possible causes, management, and outcome. Methods Retrospective study of 575 DLOWD in patients with disfiguring exophthalmos due to Graves’ ophthalmopathy performed in our hospital between 2010 and 2023. Three cases of postoperative SOFS were identified based on clinical presentation, history, physical examination, and radiological study. All patients were observed for a minimum of 12 months. Results SOFS was diagnosed with the presence of ophthalmoplegia, ptosis, fixed and dilated pupils, hypo/anesthesia of the upper eyelid and forehead, loss of corneal reflex, and no loss of vision after DLOWD. Fractures, edema, and hemorrhages were excluded. They were treated with high-dose intravenous steroids and the patients recovered completely. Conclusions DLOWD challenges orbital surgeons because it requires removing bones near the globe or neurovascular structures. SOFS may occur due to the proximity and increased pressure on these structures.

Extraocular muscle expansion after deep lateral orbital wall decompression: influence on proptosis reduction and its predictive factors.

To examine the relationship between extraocular muscle expansion and proptosis reduction (Δproptosis) in patients with thyroid eye disease who underwent deep lateral orbital wall decompression and to analyze the factors that contribute to extraocular muscle expansion. This retrospective, observational study included 133 sides from 77 patients with thyroid eye disease. The cross-sectional areas of the greater wing of the sphenoid bone (trigone), extraocular muscles, and superior ophthalmic vein were measured on computed tomographic images. Variables influencing Δproptosis were analyzed using multivariate linear regression analyses with stepwise variable selection. Predictive factors for the rate of postoperative increase in the cross-sectional extraocular muscle areas (Δextraocular muscle) were analyzed using the same statistical method. The amount of orbital fat removed (P < 0.001) and rate of Δlateral rectus muscle (P < 0.001) were positively and negatively correlated with Δproptosis, respectively (r = 0.425; adjusted r2 = 0.168; P < 0.001). The cross-sectional trigone area (P < 0.001) was positively correlated with the rate of Δlateral rectus muscle, whereas the preoperative cross-sectional lateral rectus muscle area (P < 0.001) and amount of orbital fat removed (P = 0.036) were negatively correlated with the rate of Δlateral rectus muscle (r = 0.551; adjusted r2 = 0.288; P < 0.001). Lateral rectus muscle expansion was negatively correlated with proptosis reduction and proved to be predictable before surgery. The results of this study will help predict proptosis reduction after deep lateral orbital wall decompression and to preoperatively plan additional orbital bony and fat decompression.

Orbital anatomical parameters affecting outcome of deep lateral orbital wall decompression.

To determine orbital anatomical parameters that affect surgical outcome of deep lateral orbital wall decompression. Twenty orbits of 20 patients with moderate proptosis (maximum 25 mm) due to thyroid eye disease who were stable for at least 6 months were included in this prospective cohort study. Four parameters including lateral orbital wall distance (LOWD), removable surface area (RSA), removable surface length (RSL), and sphenoid door jamb thickness (SDJ) were evaluated by computed tomography (CT) scan prior to surgery in these patients. Deep lateral orbital wall decompression without fat removal was done in all patients. Relationship between all these factors and proptosis reduction, 6 months after surgery was assessed. Mean proptosis before decompression surgery (mean ± SD) was 23.22 ± 1.19 mm and reduction in Hertel exophthalmometry (mean ± SD) was -3.27 ± 1.03 mm (p = 0.006). Pearson correlation showed that LOWD, RSL, and SDJ had statistically significant correlation with proptosis reduction (p = 0.017, 0.002, and 0.001, respectively.). Linear multivariate regression analysis showed SDJ as the only independent factor in predicting surgical outcome. several orbital anatomical factors have significant role in predicting surgical outcome following deep lateral wall orbital decompression. Among these parameters, SDJ is an independent factor, whereas LOWD and RSL are dependent factors. Preoperative assessment of the bony sphenoid anatomy may be helpful in predicting the amount of potential decompression.

Computed Tomography-Based Prediction of Exophthalmos Reduction After Deep Lateral Orbital Wall Decompression for Graves' Orbitopathy.

To examine the predictability of exophthalmos reduction using preoperative computed tomography (CT) in deep lateral orbital wall decompression for Graves' orbitopathy. This was a retrospective, observational, case-control study conducted at a single institution. Forty-three patients (43 orbits) who were treated with deep lateral decompression with (27 patients) and without (16 patients) fat removal. Multivariate linear regression analyses were used to identify factors influencing exophthalmos reduction 3 months postoperatively. Variables investigated included age; smoking history; history of corticosteroid therapy and/or radiotherapy; preoperative diplopia; width, depth, and height of the greater wing of the sphenoid bone (trigone); and volume of fat removed. The influence of these parameters on the area of the orbital opening was also analyzed. Trigone width and amount of fat removed were positively correlated with exophthalmos reduction (both, P < .050); none of the other variables exhibited significant correlations. The predictive equation for postoperative reduction in Hertel exophthalmometric values was 0.57 + 0.15 × trigone width (mm) + 1.1 × fat removed (cm3). Depth and height were positively correlated (both, P < .050) and width was negatively correlated (P = .0045) with orbital opening area. Trigone width and amount of fat removed were positive predictors of exophthalmos reduction after deep lateral decompression. Trigone width was inversely associated with orbital width, and results showed that larger exophthalmos reductions could be achieved in narrower orbits. This CT-based prediction method will assist preoperative decision-making regarding additional fat removal and/or removal of another orbital wall.

Deep lateral rim-sparing orbital wall decompression in spontaneous globe subluxation associated with shallow orbits and eyelids laxity

ABSTRACTPurpose: To share our experience on deep lateral wall rim-sparing orbital decompression for the prevention of further spontaneous globe subluxation, in patients with shallow orbits and eyelid laxity.Methods: This is a retrospective, interventional case series review. We report the results of deep lateral wall rim-sparing orbital decompression in 7 patients with recurrent spontaneous globe subluxation, operated in our department between 2010 and 2016. The orbital morphology was established by computed tomography scan images, and all patients with shallow orbit configuration and who in addition had eyelid laxity were included. Patients with thyroid eye disease were excluded.Results: No significant intraoperative and postoperative complications were encountered. In all cases, the patients were satisfied with the aesthetic result and none reported further episodes of globe subluxation.Conclusions: Deep lateral wall rim-sparing orbital decompression is a safe and effective decompressive procedure associated with minimal complications, which can be performed successfully in patients with spontaneous globe subluxation associated with shallow orbits with enough eyelid laxity.

[Efficacy and Side Effects of Lateral Orbital Wall Decompression Including the Orbital Rim in Patients with Graves' Orbitopathy].

Graves' orbitopathy is the most common extrathyroidal manifestation of Graves' disease. In the burnt out fibrotic phase exophthalmos, diplopia and lid retraction may remain, which can require multiple rehabilitative surgical interventions. Orbital decompression is an established surgical procedure for the treatment of exophthalmos in Graves' orbitopathy. The aim of the study was to evaluate the efficacy and side effects of the deep lateral orbital wall decompression including the orbital rim. In this retrospective, non-comparative case series, all patients with Graves' orbitopathy, who underwent lateral orbital wall decompression at the Eye Clinic of the University of Göttingen between 2008 and 2015, were analysed in terms of exophthalmos reduction, diplopia (Gorman score) and complications. The surgical technique involved the removal of the lateral orbital wall including the orbital rim combined with additional orbital fat resection via swinging eyelid approach. 127 patients who underwent 195 orbital decompressions were included. Mean exophthalmos reduction was 4.0 ± 1.2 mm (range 1.5 - 7.5 mm). Preoperatively, 47 patients/77 orbits (37.0/39.5%) presented without diplopia. Postoperatively, 3 patients/3 orbits (6.4/3.9%) showed new-onset diplopia (2.4% of all patients, 1.5% of all orbits). Diplopia in primary gaze was noted in one of the 3 patients (0.8% of all patients, 2.1% of patients without preoperative diplopia), and inconstant diplopia was seen in the other 2 patients. Postoperative improvement of diplopia was noted in 19 patients/19 orbits (15.0% of all patients, 23.8% of patients with preoperative diplopia/9.7% of all 195 interventions), and 16.1% of cases with preexisting diplopia. No severe complications were seen, except for one case of postoperative bleeding, which was successfully managed surgically without any functional deficits. A visible scar formation was noted in 6 cases (3.1%), temporal hollowing in 3 cases (1.5%), oscillopsia when chewing in 3 cases (1.5%) and a de-insertion of the lateral canthal region in 2 cases (1%). Deep lateral orbital wall decompression, including the orbital rim, is an effective surgical technique to reduce exophthalmos in patients with Graves' orbitopathy with a low risk of functional and aesthetic complications.

Comparison of rim-sparing versus rim-removal techniques in deep lateral wall orbital decompression for Graves’ orbitopathy

The aim of this study was to compare the surgical outcomes of deep lateral orbital decompression using the rim-sparing technique versus the rim-removal technique in Graves’ orbitopathy (GO). A retrospective cohort study of 75 orbits in 50 patients with GO was performed. Proptosis, best corrected visual acuity (BCVA), intraocular pressure (IOP), upper and lower lid margin to reflex distances (MRD-1 and MRD-2, respectively), diplopia, ocular restriction, and GO quality of life (GO-QOL) questionnaire results were analyzed pre- and postoperatively. The average proptosis reduction ranged from 3.5mm to 6.7mm with the rim-sparing technique and from 3.6mm to 6.7mm with the rim-removal technique (P>0.05). All orbits with dysthyroid optic neuropathy in the rim-sparing group and 87.5% of such orbits in the rim-removal group showed improved BCVA (P=0.321). Reductions in IOP, MRD-1, and MRD-2 were observed with both techniques. Patients in the rim-sparing group had greater improvements in GO-QOL appearance score (P=0.043). In conclusion, rim-sparing orbital decompression provides efficacious outcomes with greater improvements in patient quality of life than the rim-removal technique. The rim-sparing technique should be considered as a preferable option because it preserves the integrity of the lateral vertical maxillary buttress and bony protection for the orbital contents.

[Orbital decompression for thyroid associated ophthalmopathy: transnasal endoscopic approach or external orbital approach?]

External orbital decompression, including medial wall, inferior wall, lateral wall and orbital fat decompression alone or in combination, has long been considered to be the standard treatment for thyroid related eye diseases. Deep lateral wall orbital decompression has better effect in the balance of eye position, correction of serious exophthalmos and severe oppression optic neuropathy. Recently, however, endoscopic orbital decompression is becoming increasingly popular with the development of endoscopic surgery technique in naso-orbit related diseases. Endoscopic orbital decompression has the advantages of avoiding an external incision scar. Nevertheless, the new method also has some disadvantages, for example, application limited to medial and inferior orbital wall orbital decompression, high incidence of esotropia, need for external lateral wall decompression and expensive cost for equipment. Both surgical approaches have advantages and disadvantages respectively for medial wall and inferior wall decompression. The operative result depends on the individualized surgical design and the experience of the surgeon rather than the choice of the surgical approach. As a result, the choice of the surgical approaches should be specifically based on the patient's conditions, patient's acceptance of the operation, experience of the surgeon and available resources. (Chin J Ophthalmol, 2018, 54: 484-487).

Deep lateral wall orbital decompression following strabismus surgery in patients with Type II ophthalmic Graves’ disease

ABSTRACTPurpose: Surgical management of ophthalmic Graves’ disease traditionally involves, in order, orbital decompression, followed by strabismus surgery and eyelid surgery. Nunery et al. previously described two distinct sub-types of patients with ophthalmic Graves’ disease; Type I patients exhibit no restrictive myopathy (no diplopia) as opposed to Type II patients who do exhibit restrictive myopathy (diplopia) and are far more likely to develop new-onset worsening diplopia following medial wall and floor decompression. Strabismus surgery involving extra-ocular muscle recession has, in turn, been shown to potentially worsen proptosis. Our experience with Type II patients who have already undergone medial wall and floor decompression and strabismus surgery found, when additional decompression is necessary, deep lateral wall decompression (DLWD) appears to have a low rate of post-operative primary-gaze diplopia.Methods: A case series of four Type II ophthalmic Graves’ disease patients, all of whom had already undergone decompression and strabismus surgery, and went on to develop worsening proptosis or optic nerve compression necessitating further decompression thereafter. In all cases, patients were treated with DLWD. Institutional Review Board approval was granted by the University of Kansas.Results: None of the four patients treated with this approach developed recurrent primary-gaze diplopia or required strabismus surgery following DLWD.Conclusions: While we still prefer to perform medial wall and floor decompression as the initial treatment for ophthalmic Graves’ disease, for proptosis following consecutive strabismus surgery, DLWD appears to be effective with a low rate of recurrent primary-gaze diplopia.

Surgical Outcomes of Balanced Deep Lateral and Medial Orbital Wall Decompression in Korean Population: Clinical and Computed Tomography-based Analysis.

PurposeTo evaluate the clinical outcomes of balanced deep lateral and medial orbital wall decompression and to estimate surgical effects using computed tomography (CT) images in Korean patients with thyroid-associated ophthalmopathy (TAO).MethodsRetrospective chart review was conducted in TAO patients with exophthalmos who underwent balanced deep lateral and medial orbital wall decompression. Exophthalmos was measured preoperatively and postoperatively at 1 and 3 months. Postoperative complications were evaluated in all study periods. In addition, decompressed bone volume was estimated using CT images. Thereafter, decompression volume in each decompressed orbital wall was analyzed to evaluate the surgical effect and predictability.ResultsTwenty-four patients (48 orbits) with an average age of 34.08 ± 7.03 years were evaluated. The mean preoperative and postoperative exophthalmos at 1 and 3 months was 18.91 ± 1.43, 15.10 ± 1.53, and 14.91 ± 1.49 mm, respectively. Bony decompression volume was 0.80 ± 0.29 cm3 at the medial wall and 0.68 ± 0.23 cm3 at the deep lateral wall. Postoperative complications included strabismus (one patient, 2.08%), upper eyelid fold change (four patients, 8.33%), and dysesthesia (four patients, 8.33%). Postsurgical exophthalmos reduction was more highly correlated with the deep lateral wall than the medial wall.ConclusionsIn TAO patients with exophthalmos, balanced deep lateral and medial orbital wall decompression is a good surgical method with a low-risk of complications. In addition, deep lateral wall decompression has higher surgical predictability than medial wall decompression, as seen with CT analysis.

Lower incidence of chemosis with the Berke incision approach versus the swinging eyelid approach after deep lateral orbital wall decompression

Purpose: To compare the incidence of chemosis following deep lateral orbital wall decompression using the Berke incision approach vs the swinging eyelid approach. Methods: This study retrospectively reviewed 49 sides in 29 patients who underwent decompression via the Berke incision approach (Group A) and 122 sides in 71 patients who underwent decompression via the swinging eyelid approach (Group B). Results: The incidence of chemosis was significantly lower in Group A (30.6%) compared with Group B (48.4%; p = 0.034). Although the period until subsidence of chemosis did not differ between the groups (p = 0.164), the ratio of sides that needed intensive postoperative care was lower in Group A than in Group B (p = 0.002). Chemosis tended to occur more frequently in sides with a history of steroid administration relative to those without previous steroid administration (Group A, p = 0.042; Group B, p = 0.059), although past radiation therapy and past combined radiation and steroid therapy did not influence the occurrence of chemosis (p > 0.050). Postoperative proptosis reduction was similar in both groups (p = 0.087). Conclusion: It was found that the Berke incision approach yielded a lower incidence of chemosis while achieving similar postoperative proptosis reduction in comparison with the swinging eyelid approach. These findings suggest that the Berke incision approach is an acceptable alternative procedure for deep lateral orbital wall decompression.

Stereotactic microdebrider in deep lateral orbital decompression for patients with thyroid eye disease.

Stereotactic navigation systems have been used in neurosurgery and otolaryngology with great success. The current investigation illustrates the novel use of a microdebrider with built-in stereotactic guidance in a series of thyroid orbitopathy patients who underwent deep lateral orbital wall decompression surgery. A noncomparative, interventional, retrospective case series of patients who underwent deep lateral deep orbital wall decompression from 2006 to 2013 was conducted in accordance with Institutional Review Board policy and the Declaration of Helsinki. Patient demographics, indications for surgery, pre-, intra-, and postoperative findings along with complications were recorded. One hundred eight deep lateral orbital decompression surgeries were performed in 69 patients using the Straightshot M4 Microdebrider with built-in stereotactic guidance (Medtronics). Seventy-eight cases were in women and 30 cases were in men. The average age was 50.4 years (SD = 11.9 years). Indications for surgery included proptosis, exposure keratopathy, or compressive optic neuropathy. No patient experienced intraoperative complications. Specifically, cerebrospinal fluid leak, visual loss, infection, or unanticipated inflammation were not encountered. The average postoperative follow-up time was 5.35 months. Mean reduction in proptosis was 3.72 mm (SD = 2.1). Visual acuity improved in 32.4% (35/108) of cases. This surgical instrument combines a single handpiece locator, microdebrider, irrigator, retractor, and suction device into one. It enhances anatomical localization during orbital decompression and, with an integrated tissue guard, may decrease the risk of injury to orbital soft tissues. Stereotactic navigation enhances the surgeon's ability to determine the maximal limits of decompression in real time by confirming depth of bone removal and may potentially increase surgeons' confidence in orbital decompression surgery.

Intraocular Pressure Change With Eye Positions Before and After Orbital Decompression for Thyroid Eye Disease

To examine intraocular pressure (IOP) changes in primary and upward gazes before and after orbital decompression in patients with thyroid eye disease. Seventy-eight orbits of 40 patients who underwent orbital decompression between June 2010 and September 2012 were retrospectively reviewed. Subjects were divided in 2 groups according to the number of orbital walls removed: deep lateral orbital wall decompression group (Group A) or balanced decompression group (Group B). IOP was measured using Goldmann applanation tonometry in primary gaze and a 20° upward gaze before and 3 months after surgery. Preoperative IOP in upward gaze (18.7 mm Hg) was higher than in primary gaze (15.7 mm Hg, p < 0.001). Postoperative IOP reduction in upward gaze (3.8 mm Hg) was greater than in primary gaze (1.7 mm Hg, p < 0.001). Although the overall postoperative IOP in upward gaze (14.9 mm Hg) remained higher than in primary gaze (14.0 mm Hg, p = 0.038), the gaze-related IOP demonstrated no significant difference in all subgroups (Group A, p = 0.091; Group B, p = 0.332). IOP in upward gaze was higher prior to orbital decompression, but reduction was greater postoperatively and approximated the IOP in primary gaze.

Outcome of Deep Lateral Wall Rim-Sparing Orbital Decompression in Thyroid-associated Orbitopathy: A New Technique and Results of a Case Series

Purpose: To describe a new technique for deep lateral (single) wall orbital decompression surgery, developed by Mr. Geoffrey Rose, for proptosis in patients with thyroid-associated orbitopathy and to analyse the results achieved in our series.Methods: The study is an interventional, retrospective, non-comparative case series. Twenty-one eyes of seventeen patients underwent the described technique of deep lateral wall orbital decompression for thyroid-associated orbitopathy. All patients had controlled thyroid functions and underwent surgery for cosmetic rehabilitation, with analysis of the reduction in proptosis, changes in visual acuity and post-operative complications. The surgery involved removing the lateral orbital wall whilst preserving the lateral rim, the lateral wall being approached through a horizontal skin incision placed lateral to the lateral canthus. After reflecting the periosteum, most of the bone (deep lateral wall) between the skull base and inferior orbital fissure is removed.Results: A mean reduction in proptosis of 4.81 mm ±1.23 (SD) (p < 0.0001) with a median of 5.0 mm (range 3–7 mm) was achieved and the best-corrected visual acuity was maintained in all patients. There were no complications during surgery, and post-operative complications included worsening of pre-existing diplopia in one patient (6%) and transient cheek/temple numbness seen in three patients (18%).Conclusions: This technique of deep lateral wall orbital decompression developed by Mr. Rose is a safe and effective procedure for patients with mild to moderate proptosis. It carries a low risk of morbidity and avoids complications associated with decompressing the floor and medial wall, including new onset of motility disorders.

Advantageous Surgeon’s Position in Deep Lateral Orbital Wall Decompression

The deep lateral orbital wall decompression is now the first surgical approach in orbital decompression (). Although it is a popular procedure with few complications and satisfactory results, tips for bone removal depend on each surgeon’s experience. Here, I present differences of surgical effects, depending on the surgeon’s standing positions.

Anomaly of the Deep Lateral Orbital Wall in Two Cases

Deep lateral orbital wall decompression is considered the first choice procedure [1] in treating disfiguring proptosis, as well as, compressive optic neuropathy and congestive orbitopathy [2,3]. Although detailed normal anatomy of the deep lateral orbital wall has already been reported [1,4,5], there are no reports of anomalies of the wall. We experienced two types of anomalies of the deep lateral orbital wall in patients who underwent deep lateral orbital wall decompression.

The importance of rim removal in deep lateral orbital wall decompression

Purpose:To evaluate the surgical outcome of deep lateral orbital decompression with or without rim removal.Design:Retrospective case series.Methods:Thirty-two patients (47 orbits) with Graves’ orbitopathy who underwent simple deep lateral decompression or balanced lateral plus medial decompression. Of the 14 patients (24 orbits) who underwent simple deep lateral decompression, 8 (13 orbits) had temporary rim removal and in 6 (11 orbits) the rim was left intact. Of the 18 patients (23 orbits) who underwent a balanced decompression, 7 (9 orbits) had temporary rim removal and in 11 (14 orbits) the rim was left intact. The amount of postoperative reduction in proptosis was compared among these four groups.Results:The average reduction in proptosis in the simple deep lateral decompression group was 5.73 mm (range: 4.0–8.0 mm) in the rim removal group and 4.09 mm (range: 2.5–6.0 mm) in the intact rim group (P = 0.005). The average reduction in proptosis in the balanced decompression group was 6.39 mm (range: 5.0–8.5 mm) in the rim removal group and 5.07 mm (range: 3.0–8.0 mm) in the intact rim group (P = 0.039). There was no statistically significant difference in proptosis reduction between the simple deep lateral decompression with rim removal group and the balanced decompression with an intact rim group (P = 0.220).Conclusion:The rim removal approach allows a more effective decompression than the intact rim approach. Simple deep lateral decompression with rim removal approach has a similar effect to balanced decompression through an intact rim.

Anatomy of the Superior Border of the Lateral Orbital Wall: Surgical Implications in Deep Lateral Orbital Wall Decompression Surgery

To present the anatomical characteristics of the superior border of the lateral orbital wall and thereby reduce the risk of inadvertent dural damage during deep lateral orbital wall decompression. Twenty-five orbits (13 right and 12 left) of 13 Asian cadavers (6 men and 7 women) aged 61 to 93 years at death (average, 79.5 years) were used. After removing the orbital content, the lateral orbital wall, and the skull and brain, the superior border of the lateral orbital wall was exposed, which was analyzed from an orbital cavity view and an intracranial cavity view. The anterior part of the superior border of the lateral orbital wall is parallel with the orbital roof; however, more posteriorly, as the orbital roof curves inferiorly, they become perpendicular. The cortical bone conspicuously separates the thin superior border from the orbital roof. In the junction between the superior and the posterior borders, a thick bone marrow exists. Complete removal of this bone marrow resulted in penetration in the junction of the anterior and middle cranial fossae. The authors documented the anatomy of the superior border of the lateral orbital wall, including the different relative positions between the superior border and the orbital roof in the anterior and posterior parts of the orbit. To avoid dural exposure, the cortical bone should not be exposed at the junction between the superior and posterior borders of the lateral orbital wall, which corresponds to the junction of the anterior and middle cranial fossae.

Orbital Decompression in the Treatment of Proptosis Due to High Axial Myopia

To report the results of orbital decompression surgery for proptosis due to high axial myopia. The clinical records and imaging of 8 consecutive patients with high axial myopia who underwent orbital decompression surgery to treat disfiguring proptosis were reviewed. Data collected included preoperative and postoperative best-corrected visual acuity, Hertel exophthalmometry, ocular motility examination findings, and surgical complications. Eight patients (6 women) with a median presenting age of 53 years (range, 41-78 years) underwent unilateral bony orbital decompression surgery to treat proptosis due to unilateral or asymmetric high axial myopia. Indications for surgery were disfigurement in all patients and exposure keratopathy in 4 patients. All patients had more than 12 diopters of myopia on the operated side and axial lengths between 27.5 and 34.7 mm. Preoperative visual acuity was reduced in all patients owing to amblyopia and/or myopic retinal degeneration. In addition, 2 patients had mild symmetrical thyroid-related orbitopathy. After orbital decompression surgery, Hertel exophthalmometry measurements on the operated side were within 2 mm of the other side in all patients. The mean reduction in proptosis was 2.3 mm after deep lateral orbital wall decompression (3 patients), 4.3 mm after medial and lateral wall decompression (3 patients), and 5 mm after 3-wall decompression (2 patients). Five patients had a hypotropia on the operated side, and inferior rectus recession was performed in 4. Two patients underwent additional eyelid procedures. No surgical complications were observed. Orbital decompression to reduce proptosis in patients with unilateral or asymmetric high axial myopia can improve cosmesis with low morbidity.

Posterior Border of the Deep Lateral Orbital Wall—Appearance, Width, and Distance From the Orbital Rim

To reveal the appearance of the posterior border of the deep lateral orbital wall and to examine the width of the posterior border and distance from the lateral orbital rim to the posterior border. Twenty-seven postmortem orbits (17 right, 10 left) of 17 Asians aged from 57 to 101 years at death (average, 81.6 years) fixed in 10% buffered formalin were examined. After removing the deep lateral orbital wall except for its posterior border, we first observed the appearance of the posterior border, and then confirmed its thinness by using a light source behind the posterior border. Next, the width of the posterior border and distance from the orbital rim to the posterior border were measured at a position 8 mm superior to the inferior orbital rim. The posterior border of the deep lateral orbital wall was very thin. The width of the posterior border was almost constant at each level. The light was strongly visible through the bone of the posterior border. The average width of the posterior border was 17.6 mm OD and 17.3 mm OS, whereas the average distance from the orbital rim to the posterior border was 32.9 mm OD and 32.7 mm OS. Lateralities were not demonstrated in both categories. This information regarding the true appearance of the posterior border and its width and distance from the orbital rim will ensure that surgeons can safely and confidently perform deep lateral orbital wall decompression.