Novel optical coherence tomography findings in a patient with methanol toxicity: a case report.

We report a case of acute methanol toxicity with unique optical coherence tomography findings. A 56-year-old man was referred to our ophthalmology clinic with a history of handmade vodka consumption and vision loss. On ophthalmologic examination, his vision was 20/100 in his right eye and 20/200 in his left eye. Bilateral mild optic disk hyperemia was detected on fundus examination. Because of the severity of systemic symptoms in such cases, it is very difficult to include optical coherence tomography in the ophthalmologic examination. However, we managed to perform optical coherence tomography and recorded shallow subretinal fluid and a prominent middle limiting membrane sign as acute retinal structural changes in the patient. The patient was treated with hemodialysis, intravenous ethanol, and sodium bicarbonate. On the fourth day of treatment, visual acuity improved to 20/20 in both eyes. In addition, the prominent middle limiting membrane sign and subretinal fluid disappeared. In this unusual case, retinal pigment epithelium damage and retinal ischemia may have contributed to the prominent middle limiting membrane and subretinal fluid, which are novel optical coherence tomography findings of methanol toxicity.

Novel optical coherence tomography findings in a patient with methanol toxicity: a case report

ABSTRACT We report a case of acute methanol toxicity with unique optical coherence tomography findings. A 56-year-old man was referred to our ophthalmology clinic with a history of handmade vodka consumption and vision loss. On ophthalmologic examination, his vision was 20/100 in his right eye and 20/200 in his left eye. Bilateral mild optic disk hyperemia was detected on fundus examination. Because of the severity of systemic symptoms in such cases, it is very difficult to include optical coherence tomography in the ophthalmologic examination. However, we managed to perform optical coherence tomography and recorded shallow subretinal fluid and a prominent middle limiting membrane sign as acute retinal structural changes in the patient. The patient was treated with hemodialysis, intravenous ethanol, and sodium bicarbonate. On the fourth day of treatment, visual acuity improved to 20/20 in both eyes. In addition, the prominent middle limiting membrane sign and subretinal fluid disappeared. In this unusual case, retinal pigment epithelium damage and retinal ischemia may have contributed to the prominent middle limiting membrane and subretinal fluid, which are novel optical coherence tomography findings of methanol toxicity.

Choroidal structural changes in patients with early diabetic nephropathy.

PURPOSE: To determine alterations of the choroidal thickness (CT) and the choroidal vascularity index (CVI) in patients with glomerular hyperfiltration, a marker of early diabetic nephropathy (DN). METHODS: Twenty-two patients with type 2 diabetes (T2D) with glomerular hyperfiltration (early DN group) and 28 patients with T2D without DN (NDN group) were included in the study. Patients with diabetic retinopathy were excluded. Parameters including subfoveal CT, the subfoveal choroidal vascularity index (CVI), and total CVI were measured using spectral-domain enhanced depth imaging optical coherence tomography method. RESULTS: The early DN group included 22 patients and the NDN group comprised 28 patients. The groups were similar in terms of age and sex (p>0.05). The CT values were statistically significantly lower in the early DN group than in the NDN group (p < 0.001). There was no significant difference between the early DN group and the NDN group in terms of total and subfoveal CVI (p>0.05). CONCLUSION: The choroidal thickness decreased in patients with T2D with glomerular hyperfiltration, but there were no differences in CVI when they were compared with patients with T2D without DN.

Choroidal structural changes in airline pilots and cabin crew.

PURPOSE: To analyze the differences in terms of choroidal vascularity index (CVI) and choroidal thickness (CT) between the airline pilots-cabin crew and the normal population. METHODS: In this prospective study, 50 airline pilots-cabin crew (study group) and 50 healthy individuals (control group) were included for comparison. For each participant, one eye, the eye with the higher OCT scan score index, was enrolled. Subfoveal CT and CVI were measured using a spectral-domain optical coherence tomography system with enhanced depth imaging. RESULTS: There were no significant differences in terms of age and sex between the study and control groups. The mean CT was 368.5 ± 79.6 in the control group vs. 424.9 ± 80.7 in the study group (p = 0.001). CT was significantly thicker in the study group. The mean CVI was 64.3 ± 1.5 in the control group and 66 ± 3.1 in the study group (p = 0.5). There was no significant correlation between the study and control groups in terms of CVI. CONCLUSION: Airline pilots-cabin crew had thicker CT, but there were no differences in CVI when they were compared with healthy subjects. The effect of unique occupational exposures of airline pilots-cabin crew to the pathophysiology of choroidal structural alterations needs further investigation.

Characteristics and management of macular hole developing after rhegmatogenous retinal detachment repair.

PURPOSE: To report characteristics of patients developing full-thickness macular hole (MH) after rhegmatogenous retinal detachment (RRD) repair surgery. We also compared patients developing MH with and without accompanying RRD recurrence regarding anatomical and visual outcomes of MH repair. DESIGN: Retrospective study. METHODS: Medical records of patients who developed MH after RRD repair between January 2002 and January 2018 were reviewed. RESULTS: We performed 1661 primary RRD operations during the study period and 14 of these developed MH, an incidence of 0.8%. Nine patients had their primary RRD repair surgery in another clinic and were referred to our clinic after development of MH. In total 23 patients with MH secondary to RRD repair were included in the study. The type of RRD repair surgery was scleral buckling only in 4 patients (17%), pars plana vitrectomy (PPV) only in 14 patients (61%), and sequential scleral buckling and PPV in 5 patients (22%). Nineteen patients (83%) had macula-off RRD. In 12 patients (52%), MH developed within 3 months after RRD repair. Surgery for MH repair was performed in 18 patients. Postoperative best corrected visual acuity (BCVA) was better than preoperative BCVA in the group with RRD recurrence as well as in the group without RRD recurrence (both P < 0.05). There wasn't a significant difference between these groups regarding postoperative visual gain and anatomical success (P > 0.05). CONCLUSION: MH can develop after various surgical methods of RRD repair. Anatomic closure and visual acuity gain can be achieved even if patients have accompanying RRD recurrence.

REPEATABILITY OF CHOROIDAL VASCULARITY INDEX MEASUREMENTS USING DIRECTIONAL OPTICAL COHERENCE TOMOGRAPHY IMAGES.

PURPOSE: To investigate the repeatability of choroidal vascularity index (CVI) measurements in centered and decentered (regarding pupil entry position of the beam) directional subfoveal optical coherence tomography (OCT) scans with (CVI1) and without (CVI2) brightness adjustment. METHODS: Thirty-two eyes of 32 healthy volunteers were included in this prospective study. First, the fovea was evaluated by a single horizontal enhanced depth imaging OCT scan in a centered direction. Then, the same subfoveal horizontal line was scanned in a decentered direction. The agreement between CVIs obtained from these centered and decentered directional OCT scans was investigated using Bland-Altman analysis and intraclass correlation coefficient. RESULTS: Intraclass correlation coefficient between centered and decentered CVI1 was 0.71 (95% CI: 0.48-0.85, P value < 0.001). Intraclass correlation coefficient between centered and decentered CVI2 was 0.73 (95% CI: 0.5-0.86, P value < 0.001). The mean difference between centered and decentered directional measurements for CVI1 and CVI2 were 0.5 and 0.8, respectively. CONCLUSION: There is moderate agreement between CVIs obtained from centered and decentered directional single OCT scans of the same subfoveal area. Studies investigating choroidal vascularity should be standardized by using the same OCT beam direction in all scans.

TRANSCORNEAL SUTURELESS SILICONE OIL REMOVAL USING 23-GAUGE TROCAR SYSTEM IN APHAKIA.

PURPOSE: To describe transcorneal sutureless silicone oil removal using 23-gauge trocars as an alternative surgical technique in an aphakic eye. METHODS: We retrospectively evaluated the management of a 50-year-old male patient who had a history of bilateral congenital cataract removal at the age of 5 and developed rhegmatogenous retinal detachment. A 3-port 23-gauge pars plana vitrectomy, removal of the vitreous up to the vitreous base, 60° temporal retinotomy, and anterior flap retinectomy were performed. Silicone oil (1,000 cSt) was selected as a tamponading agent. The patients underwent active silicone oil removal at subsequent surgery 2 months after the initial vitrectomy. RESULTS: The silicone oil was successfully extracted from the aphakic eye by using transcorneal 23-gauge trocars. No suture was needed at the corneal wound sites. There were no intraoperative or postoperative complications. CONCLUSION: Transcorneal silicone oil removal using 23-gauge trocars can be performed easily with today's modern vitreoretinal surgery systems as an alternative treatment modality.

DEVELOPMENT OF PACHYCHOROID PIGMENT EPITHELIOPATHY AND TRANSFORMATION TO CENTRAL SEROUS CHORIORETINOPATHY AFTER INTRAVITREAL DEXAMETHASONE IMPLANTATION.

PURPOSE: To report first case of sequential development of pachychoroid pigment epitheliopathy (PPE) and central serous chorioretinopathy (CSC) after repeated intravitreal dexamethasone implantations for diabetic macular edema treatment. METHODS: We present a case of a 54-year-old man having intravitreal dexamethasone implant for bilateral diabetic macular edema. RESULTS: We observed development of pachychoroid pigment epitheliopathy, seen as a small pigment epithelial detachment on optical coherence tomography after a fourth dexamethasone implantation. A fifth implantation caused transformation of pachychoroid pigment epitheliopathy to central serous chorioretinopathy. CONCLUSION: Consecutive administration of dexamethasone implants may have a cumulative effect on retinal pigment epithelium, Bruch membrane, and choroid.

Spectral domain optical coherence tomography classification of diabetic macular edema: a new proposal to clinical practice.

PURPOSE: To classify the types of diabetic macular edema (DME) and evaluate its morphological features on spectral domain optical coherence tomography (SD-OCT) and determine correlations between visual acuity and OCT findings. METHODS: We assessed 406 eyes of 309 patients with a diagnosis of DME retrospectively. Three types based on SD-OCT were identified: diffuse macular edema, cystoid macular edema, and cystoid degeneration. Morphological features such as serous macular detachment (SMD), vitreomacular interface abnormalities (VMAI), hard exudates, photoreceptor status, and correlations between visual acuity and those morphological features were also evaluated by SD-OCT. RESULTS: The most common type of DME was cystoid edema (68.5%). No statistically significant difference was found between groups in sex (P = 0.40), type of diabetes (P = 0.50), or diabetic retinopathy (P = 0.78). However, the duration of symptoms and BCVA was significantly lower in the group with cystoid degeneration compared with the group with cystoid edema (P < 0.001) and the group with diffuse macular edema (P < 0.001). In the group with cystoid degeneration compared with the groups with cystoid and diffuse edema, the central fovea and central subfield were significantly thicker (both (P < 0.001), the subfoveal choroid was significantly thinner (P = 0.049), rate of serous macular detachment was significantly lower (P < 0.001), and the rate of outer retinal damage was significantly higher (P < 0.001). CONCLUSIONS: Cystoid macular degeneration, which is consistent with poor functional and morphological outcomes, should be differentiated from cystoid macular edema. Serous macular detachment, which is mostly seen in eyes with early stages of DME, should be evaluated as an accompanying morphological finding rather than a type of DME.

Features of neovascularization in pachychoroid neovasculopathy compared with type 1 neovascular age-related macular degeneration on optical coherence tomography angiography.

PURPOSE: To compare neovascular membrane features of pachychoroid neovasculopathy (PNV) and type 1 neovascular age-related macular degeneration (nAMD) using optical coherence tomography angiography (OCTA). DESIGN: Retrospective study. METHODS: We assessed 34 treatment-naïve eyes with a diagnosis of PNV and 36 treatment-naïve eyes with a diagnosis of type 1 nAMD. Morphological patterns of neovascular membranes were categorized, and lesion sizes and flow areas were calculated by using en face images on the AngioVue (Optovue) OCTA system. RESULTS: Statistically significant differences were found between groups in age (P=0.001), baseline best corrected visual acuity (P=0.005), and baseline subfoveal choroidal thickness (P<0.001). However, there were no statistically significant differences in membrane morphology (P=0.86), lesion size (P=0.80), or flow area (P=0.96). All membranes that could be detected by OCTA could also be detected by indocyanine green angiography (ICGA). However, OCTA could not identify the neovascularization in 11.8% of the eyes with PNV and 16.7% of the eyes with nAMD, which could be identified on ICGA images. CONCLUSIONS: PNV is seen in younger patients and in patients with thicker choroids, but in terms of morphological characteristics and vessel density, membranes detected by OCTA are not different from those of nAMD. Dye angiography remains the gold standard for identifying neovascularization, especially in treatment-naïve patients, owing to blockage of fluid and hemorrhage and scattering of OCTA signals.

DOUBLE ARCUATE RELAXING RETINOTOMY FOR A LARGE MACULAR HOLE.

PURPOSE: To describe double arcuate relaxing retinotomy as an alternative surgical technique in a case with a secondary large macular hole. METHODS: The management of a patient who developed a large macular hole and macular tractional rhegmatogenous retinal detachment after pars plana vitrectomy for proliferative diabetic retinopathy was retrospectively assessed. Despite surgical procedures, such as dissection of a preretinal membrane from the retina and peeling of the retinal internal limiting membrane, the macular hole could not be closed. In the absence of an alternative method, superior and inferior posterior arcuate, 120° relaxing retinotomies were performed. RESULTS: At the follow-up, the macular hole closure was confirmed by clinical examination and optical coherence tomography imaging, and visual acuity improved. There were no intraoperative or postoperative complications. CONCLUSION: In cases of large macular holes, double arcuate relaxing retinotomy can reduce traction, leading to hole closure.

Evaluation of Prelaminar Region and Lamina Cribrosa with Enhanced Depth Imaging Optical Coherence Tomography in Pseudoexfoliation Glaucoma.

OBJECTIVES: To analyze optic nerve head images of pseudoexfoliative glaucoma (PXG) patients and healthy volunteers obtained with enhanced depth imaging spectral domain-optical coherence tomography (SD-OCT). MATERIALS AND METHODS: Seventy patients with PXG and 68 age- and gender-matched healthy subjects were included in this prospective study. The prelaminar tissue and lamina cribrosa were imaged using spectralis OCT with the enhanced depth imaging technique. PXG disease stage was determined with visual field to evaluate relationships between prelaminar tissue thickness (PTT), lamina cribrosa thickness (LT) and disease severity. RESULTS: There was no significant difference between the PXG group and control group with regard to age, gender, central corneal thickness, or axial length. The mean PTT (93.1±44.5 µm, p<0.05) and LT (206.3±33.6 µm p<0.05) values of the PXG group were significantly lower compared to the control group in enhanced depth imaging OCT measurements. The PXG patients were divided into stages according to visual field defect severity. While a significant difference was not detected in PTT based on disease stage (p>0.05), a statistically significant difference was detected between stages for LT (p<0.05). CONCLUSION: A thinner PTT was correlated with the presence of PXG but not with the severity of glaucoma. In addition, LT has a stronger relationship with disease severity and progression compared to PTT.

Functional and anatomical outcomes following surgical management of persistent fetal vasculature: a single-center experience of 44 cases.

PURPOSE: To investigate the functional and anatomical outcomes following surgical management of persistent fetal vasculature (PFV). METHODS: Single-center, retrospective, interventional consecutive case series of 41 patients (44 eyes) who underwent vitrectomy with or without lensectomy through a limbal or pars plana/plicata approach with diagnosis of anterior, posterior, or combined anterior and posterior segment PFV were included. RESULTS: The median age at the time of surgery was 3 months (range, 1-36 months), and the mean follow-up period was 37.2 ± 38.1 months (range, 12-164 months). Of the 44 eyes, 5 (11%) had clinical and ultrasonographic findings of anterior PFV, 5 (11%) had posterior PFV, and 34 (78%) had components of both anterior and posterior disease. At the last visit, 38 eyes (87%) were aphakic, 5 eyes (11%) were phakic, and 1 eye (2%) was pseudophakic. The mean Snellen equivalent VA at the final visit for the 14 (32%) eyes with measurable VA was 20/283. Nine (20%) eyes had final VA of only light perception or no light perception. The remaining 21 (48%) eyes behaved consistently with form vision, but the patients were not able to report VA. CONCLUSIONS: Most of the eyes achieved at least form vision, with acceptable postoperative complication rates. Functional and anatomical outcomes are not strictly dependent on axial length, and microphthalmic eyes with mild posterior segment involvement have the potential for good visual results. Outcomes after surgery for posterior PFV associated with tractional retinal detachment are limited. Anatomical success does not always equate to functional improvement.

FEATURES OF THE MACULA AND CENTRAL VISUAL FIELD AND FIXATION PATTERN IN PATIENTS WITH RETINITIS PIGMENTOSA.

PURPOSE: To evaluate macular features and fixation pattern in patients with retinitis pigmentosa (RP) compared with healthy controls, using spectral-domain optical coherence tomography and MP-1 microperimetry. METHODS: Eighty-one eyes of 81 patients with RP and 90 eyes of 90 healthy subjects were assessed. The central foveal thickness, subfoveal choroidal thickness, ellipsoid zone length, and the mean retinal sensitivities and fixation characteristics were evaluated by spectral-domain optical coherence tomography and MP-1 microperimetry. RESULTS: Compared with healthy subjects, patients with central macular thinning had lower best corrected visual acuity, central foveal thickness, ellipsoid zone length, retinal sensitivity, and visual field than patients with cystoid macular edema or no macular change (all P < 0.001). Correlations between fixation characteristics and best corrected visual acuity, central foveal thickness, ellipsoid zone length, retinal sensitivity, and visual field were statistically significant (all P < 0.001). Patients with no macular change had more centralized and stabilized fixation than patients with central foveal thinning and cystoid macular edema. CONCLUSION: The spectrum of macular features from the nearly normal retina to complete chorioretinal atrophy can be seen in RP patients without associations with age or duration of symptoms. Unlike other macular degenerations, most patients with RP obtained at least a central 2° of visual field, with foveal and stable fixation.

Anatomical and functional outcomes following vitrectomy for dense vitreous hemorrhage related to Terson syndrome in children.

PURPOSE: Our purpose was to assess anatomical and functional outcomes of vitrectomy in pediatric cases of Terson syndrome. METHODS: A total of 11 eyes of seven children diagnosed with Terson syndrome secondary to traumatic brain injury and 17 eyes of 12 children diagnosed with Terson syndrome secondary to nontraumatic brain hemorrhage who had 20-gauge or 23-gauge pars plana or pars plicata vitrectomy were included in this retrospective study. The primary outcome was the change in visual acuity from the preoperative examination to postoperative final follow-up. Secondary outcomes were anatomic surgical success and postoperative complications. RESULTS: The mean time between diagnosis and surgery was 62 ± 35 days (range, 30-150), and the average age at the time of the surgery was 4.5 ± 6.4 years (range, 3 months to 17 years). The mean preoperative logarithm of the minimum angle of resolution (logMAR) (Snellen) best corrected visual acuity (BCVA) was 2.6 ± 0.7 (20/7260) (n = 9) and in the remaining 19 eyes it was recorded as noncentral, unsteady, nonmaintained fixation. The mean follow-up period was 50 ± 54 months (range, 12-192 months). At the last follow-up visit, the mean logMAR BCVA was 0.46 ± 0.6 (20/60) (n = 19) and in eight eyes it was recorded as fix-and-follow. One eye developed a retinal detachment 14 months after the first operation, and one eye developed an epiretinal membrane after 2 years. Anatomical success was recorded in all patients at the final visit. CONCLUSIONS: In children with massive vitreous hemorrhage secondary to Terson syndrome, vitrectomy is an effective procedure and offers a rapid visual improvement. Earlier surgical treatment prevents amblyopia and blood-related potential complications.

Correlation between morphological changes and functional outcomes of recent-onset macula-off rhegmatogenous retinal detachment: prognostic factors in rhegmatogenous retinal detachment.

PURPOSE: To assess correlation between preoperative and postoperative findings and surgical factors, and postoperative functional outcomes after successful repair of acute macula-off rhegmatogenous retinal detachment (RRD). METHODS: Forty-four eyes of 44 patients with recent-onset macula-off RRD who had primary pars plana vitrectomy were included in this retrospective study. Best-corrected visual acuity (BCVA) and retinal and choroidal changes on spectral-domain optical coherence tomography (SD-OCT) were evaluated before and after surgery. Correlation between preoperative and postoperative variables such as demographic and clinical data, SD-OCT findings and surgical factors, and postoperative functional outcomes were assessed. RESULTS: Eighteen women and 26 men, whose mean age at the onset of RRD was 51.7 ± 14.4 years, were evaluated. The mean preoperative and postoperative logMAR BCVA were 1.1 ± 0.5 (20/250) and 0.14 ± 0.1 (20/30), respectively, after a mean of 16.7 ± 7.2 months. Although all factors were evaluated as prognostic factors for functional outcome after surgical treatment of recent-onset macula-off RRD, epiretinal membrane formation was found as the only factor affecting postoperative visual acuity. CONCLUSION: Satisfactory visual recovery can be achieved after a successful surgery in patients with acute RRD without any association with morphological changes such as increased subretinal fluid, central foveal thickness, subfoveal choroidal thickness, cystic spaces in the inner nuclear layer and/or outer nuclear layer, undulation of separated outer retina, and disruption of the photoreceptor layer. Epiretinal membrane formation may affect visual outcome in these patients.

Choroidal thickness in chronic rhegmatogenous retinal detachment before and after surgery, and comparison with acute cases.

PURPOSE: To evaluate subfoveal choroidal thickness (SCT) in cases with chronic rhegmatogenous retinal detachment (RRD), before and after pars plana vitrectomy, and cases with acute RRD using optical coherence tomography. METHODS: This retrospective study included 24 eyes with chronic RRD and 26 eyes with recent-onset RRD. Best corrected visual acuity, intraocular pressure, and SCT were measured and compared between the two groups. Of 24 eyes with chronic RRD, 11 had primary pars plana vitrectomy. Measurements of operated and fellow eyes were also compared before surgery and 1 week, 1 and 3 months after surgery. RESULTS: The preoperative mean SCT in eyes with chronic RRD was 342.6 ± 111.7 µm and in fellow eyes 342.4 ± 116.7 µm (P = 0.83) and in eyes with acute RRD was 346.2 ± 51 µm and in fellow eyes 262.7 ± 46.8 µm (P < 0.001). There was also no significant change in SCT between baseline before surgery and 3 months after surgery in eyes with chronic RRD (P = 0.20). CONCLUSION: No significant difference was found in the mean SCT between affected and fellow eyes in chronic RRD. This may be related to intraocular inflammation, which is more limited in chronic than in acute RRD. There was also no significant difference in the SCT in eyes with chronic RRD between the operated and fellow eyes after surgery. It may be concluded that vitrectomy does not affect choroidal thickness.

THERAPEUTIC OUTCOMES AFTER ENDORESECTION OF COMPLEX RETINAL CAPILLARY HEMANGIOBLASTOMA.

PURPOSE: To evaluate the anatomical and functional outcomes after endoresection of complex retinal capillary hemangioblastoma (RCH). METHODS: Retrospective case series of 12 patients (13 eyes), all treated with pars plana vitrectomy, endodiathermy of feeding and draining vessels, endoresection of RCH and silicone oil injection. RESULTS: The mean age at the time of surgery was 32.5 ± 15.9 years. The mean follow-up duration after initial surgery was 50.5 ± 49.4 months. Indications for surgery included RCH with associated complications such as tractional retinal detachment in five eyes (38%), exudative retinal detachment in four eyes (31%), and combination of tractional retinal detachment and exudative retinal detachment in four eyes (31%). The dimensions of the resected RCHs were as follows: >3.0 mm in seven eyes (54%), >3.5 mm in three eyes (23%), and >4.0 mm in three eyes (23%). No tumor was located closer than 10 mm to the optic nerve or fovea. Anatomical success after initial surgery was 92%. One eye had a second vitreoretinal procedure owing to recurrent RD. The mean preoperative Snellen visual acuity was 20/303. The mean Snellen visual acuity at the final visit was 20/73. At the final visit, visual acuity had improved in seven eyes (54%), and six eyes (46%) were stable. Short-term complications included recurrent proliferative vitreoretinopathy in one eye (8%), transient ocular hypertension requiring topical antiglaucoma treatment in four eyes (31%), and long-term complications included progression of cataract in seven eyes (54%). CONCLUSION: Combined pars plana vitrectomy, endodiathermy of feeding and draining vessels, endoresection of RCH, and silicone oil injection may be an effective treatment option for complex RCH, achieving high anatomical success and stable or even improved visual acuity, acceptable rates of disease- and treatment-related complications, and minimal need for retreatment.