Macular and peripapillary retinal nerve fiber layer thickness in children with hyperopic anisometropic amblyopia

AIM:To compare the retinal nerve fiber layer (RNFL) thickness and macular thickness in the amblyopic eye with that in the sound eye of children with hyperopic anisometropic amblyopia using optical coherence tomography (OCT).METHODS: A prospective, nonrandom, intraindividual comparative cohort study includes 72 children with hyperopic anisometropic amblyopia in a single center. Macular thickness, macular foveola thickness, and peripapillary RNFL thickness were compared between the amblyopia eyes and the contralateral sound eyes.RESULTS:There were 38 male and 34 female patients, with a mean age as 9.7±1.9 years (range, 5–16 years). Hyperopic was +3.62±1.16D (range +2.00D to +6.50D) in the amblyopic eyes, which was significantly higher in the control eyes with +0.76±0.90D (range 0D to +2.00D) (P < 0.01). The mean peripapillary RNFL thickness was 113.9±7.2µm and 109.2±6.9µm in the amblyopic eye and the normal eye, respectively, reaching statistical significance (P = 0.02). The mean macular foveola thickness was significantly thicker in the amblyopic eyes than the contralateral sound eyes (181.4±14.2µm vs 175.2±13.3µm, P < 0.01), but the 1mm, 3mm or 6mm macular thickness central macular thickness was not significantly different. Degree of anisometropia in the contralateral eyes was not significantly correlated with differences of peripapillary RNFL, macular foveola thickness or central macular thickness.CONCLUSION:Eyes with hyperopic anisometropic amblyopia are found thicker macular foveola and peripapillary RNFL than the contralateral eyes in children.     

Retinal nerve fiber layer thickness in normal Indian pediatric population measured with optical coherence tomography

Purpose:

To measure the peripapillary retinal nerve fiber layer (RNFL) thickness in normal Indian pediatric population.

Subjects and Methods:

120 normal Indian children ages 5-17 years presenting to the Pediatric Clinic were included in this observational cross-sectional study. RNFL thickness was measured with stratus optical coherence tomography (OCT). Children with strabismus or amblyopia, with neurological, metabolic, vascular, or other disorders and those with abnormal optic discs were excluded. One eye of each subject was randomly selected for statistical analysis. The effect of age, refraction and gender on RNFL thickness was investigated statistically.

Result:

OCT measurements were obtained in 120 of 130 (92.3%) subjects. Mean age was 10.8 ± 3.24 years (range 5-17). Average RNFL thickness was (± SD) 106.11 ± 9.5 μm (range 82.26-146.25). The RNFL was thickest inferiorly (134.10 ± 16.16 μm) and superiorly (133.44 ± 15.50 μm), thinner nasally (84.26 ± 16.43 μm), and thinnest temporally (70.72 ± 14.80 μm). In univariate regression analysis, age had no statistical significant effect on RNFL thickness (P =0.7249) and refraction had a significant effect on RNFL thickness (P =0.0008).

Conclusion:

OCT can be used to measure RNFL thickness in children. Refraction had an effect on RNFL thickness. In normal children, variation in RNFL thickness is large. The normative data provided by this study may assist in identifying changes in RNFL thickness in Indian children.     

Normative spectral domain optical coherence tomography data on macular and retinal nerve fiber layer thickness in Indians

Aim:

To provide the normative data of macular and retinal nerve fiber layer (RNFL) thickness in Indians using spectral domain OCT (Spectralis OCT, Heidelberg Engineering, Germany) and to evaluate the effects of age, gender, and refraction on these parameters.

Design:

Observational, cross-sectional study.

Materials and Methods:

The eyes of 105 healthy patients aged between 20-75 years, with no ocular disease and best corrected visual acuity of 20/20, were scanned using standard scanning protocols by a single examiner. Exclusion criteria included glaucoma, retinal diseases, diabetes, history of prior intraocular surgery or laser treatment. The mean macular and RNFL thickness were recorded, and the effects of age, gender, and refraction on these parameters were evaluated. This data was compared with published literature on Caucasians to assess the ethnic variations of these parameters.

Results:

The normal central foveal thickness in healthy Indian eyes measured using Spectralis OCT was 260.1 ± 18.19 μm. The nasal inner quadrant showed maximum retinal thickness (338.88 ± 18.17 μm). The mean RNFL thickness was 101.43 ± 8.63 μm with maximum thickness in the inferior quadrant. The central foveal thickness showed a gender-based difference (P = 0.005) but did not correlate significantly with age (P = 0.134), whereas the parafoveal, perifoveal thickness, macular volume, and RNFL thickness showed significant negative correlation with age.

Conclusions:

Our study provides the normative database for Indians on Spectralis OCT. It also suggests that age should be considered while interpreting the macular thickness and RNFL, whereas gender should also be given consideration in central foveal thickness.     

Can ganglion cell complex assessment on cirrus HD OCT aid in detection of early glaucoma?

Context

Ganglion cell complex is damaged early in glaucoma. Does this loss of GCC help in early diagnosis of glaucoma.

Aims

To compare the RNFL thickness and ganglion cell complex (GCC) in diagnosed patients of glaucoma, pre-perimetric glaucoma and normal controls.

Settings and design

Case controlled, observational study.

Methods and material

33 glaucoma patients, 45 pre-perimetric glaucoma, and 30 controls were enrolled in the study. ONH parameters on cirrus HD OCT like CD ratio, para papillary RNFL thickness and GCC were calculated for each case.

Statistical analysis used

ANOVA test to analyse differences between groups. ROC for ganglion cell layer.

Results

RNFL thickness was 71.6 μ and GCC was 69.19 μ in glaucoma patients. RNFL thickness was 77.31 μ and GCC was 71 μ in pre-perimetric glaucoma and 99.6 μ and 85.16 μ in controls respectively. The difference of mean for RNFL and GCC by ANOVA was statistically significant for controls, glaucoma patients and pre-perimetric glaucoma patients. RNFL (p < 0.001) and GCC (p < 0.001). Receiver operating characteristic curve for GCC was 0.83 (p < 0.000).

Conclusions

The RNFL analysis is increasingly being used as newer tool in diagnosis of glaucoma. In addition, GCC can be used as a supplementary tool in picking up cases of pre-perimetric glaucoma as loss is significant in pre-perimetric glaucoma also.     

Comparison of retinal nerve fiber layer and macular thickness measurements with Stratus OCT and OPKO/OTI OCT devices in healthy subjects

AIM: To compare retinal nerve fiber layer (RNFL) and macular thickness measurements obtained with the Stratus optical coherence tomography (OCT) and OPKO/OTI OCT devices. METHODS: Included in the study were 59 eyes of 30 participants. All measurements for each eye were done on the same day with both devices. Student’s paired t-tests were used to compare the central macular thickness and RNFL measurements of the Stratus OCT and OPKO/OTI OCT. Pearson correlation was used to assess the relationship between the devices. Coefficient of variation (COV) was calculated to assess intersession repeatability. RESULTS: Using both the Stratus OCT and OPKO/OTI OCT, respectively, the measured mean average RNFL thicknesses were 98.9±11.1 μm and 115.1±9.6 μm (P=0.001), and the measured mean central retinal thicknesses (CRT) were 196.2±18.8 μm and 204.5±21.1 μm (P<0.001). Measured by the two devices, the RNFL thickness values were correlated in all quadrants, as were the retinal thickness values except the inferior outer sector. COV for average RNFL and CRT thickness were 2.9% and 4.6% for Stratus OCT, and 2.1% and 4.2% for OPKO/OTI OCT, respectively. CONCLUSION: We found good reproducibility of RNFL and retina thickness measurements for both Stratus OCT and OPKO/OTI OCT devices. However, even though the two OCT systems provided statistically correlated results, the values for both RNFL and macular thickness were statistically different. RNFL and macular thickness measurements with the OPKO/OTI OCT were higher than that of the Stratus OCT; therefore, the two OCT systems cannot be used interchangeably for the measurements of RNFL and macular thickness.     

Retinal nerve fiber layer and optic disc measurements by spectral domain OCT: normative values and associations in young adults

Purpose

To determine normative values and associations of retinal nerve fiber layer (RNFL) and optic disc parameters in normal eyes measured by spectral domain optical coherence tomography (OCT).

Methods

In a population-based setting, 1521 young adults were examined as part of the Sydney Adolescent Vascular and Eye Study (SAVES). Their mean age was 17.3±0.6 years. RNFL and optic disc parameter measurements were made using Cirrus HD-OCT 4000.

Results

The average RNFL was found to be 99.4±9.6 μm. RNFL thickness was least for the temporal quadrant (69.9±11.2 μm), followed by the nasal (74.3±12.8 μm), superior (124.7±15.7 μm) and inferior (128.8±17.1 μm) quadrants. The mean disc area in this population was 1.98±0.38 mm² with a mean rim area of 1.50±0.30 mm² and a mean cup/disc ratio of 0.44±0.18. Multivariate-adjusted RNFL thickness was marginally greater in East Asian than in white participants (100.1 μm vs 99.5 μm; P=0.0005). The RNFL was thinner with greater axial length (P<0.0001), less positive spherical equivalent refractions (P<0.0001), smaller disc area and rim area (P<0.0001).

Conclusion

This study documents normative values for the RNFL and optic disc measured using Cirrus HD-OCT in young adults. The values and associations reported in this study can inform clinicians on the normal variation in RNFL and optic disc parameters.     

Radiation Macular Edema after Ru-106 Plaque Brachytherapy for Choroidal Melanoma Resolved by an Intravitreal Dexamethasone 0.7-mg Implant

Purpose

To report the effective treatment of radiation macular edema following ruthenium-106 plaque brachytherapy for a choroidal melanoma with a dexamethasone 0.7-mg (Ozurdex^®) intravitreal implant.

Methods

An interventional case report with optical coherence tomography (OCT) scans.

Results

A 65-year-old Caucasian woman was suffering from radiation macular edema following ruthenium-106 plaque brachytherapy for a choroidal melanoma on her left eye. She had undergone one intravitreal injection of 0.5 mg bevacizumab (Avastin^®, Genentech/Roche) in the following months without functional or anatomical improvement. Seven months after the development of radiation macular edema, she received a single intravitreal injection of dexamethasone 0.7 mg (Ozurdex). Four weeks following the injection, her best-corrected visual acuity improved from 0.3 to 0.5. Radiation macular edema resolved with a reduction of central retinal thickness from 498 μm before Ozurdex injection to 224 μm after Ozurdex injection, as measured by OCT scan.

Conclusion

Dexamethasone 0.7 mg (Ozurdex) has proven to be an effective treatment option in retinal vein occlusion and noninfectious uveitis. It can also be considered as off-label treatment in radiation macular edema following ruthenium-106 plaque brachytherapy for a choroidal melanoma.Key Words: Choroidal melanoma, Ru-106 plaque, Macular edema, Dexamethasone 0.7 mg, Ozurdex^®     

Evaluation of peripapillary retinal nerve fiber layer, macula and ganglion cell thickness in amblyopia using spectral optical coherence tomography

AIM:To investigate peripapillary retinal nerve fiber layer (RNFL), macula and ganglion cell layer thicknesses (GCC) in amblyopic eyes with spectral domain optical coherence tomography (SD-OCT).METHODS:Thirty six patients with a history of unilateral amblyopia and thirty two children who had emmetropia without amblyopia were included in this study.In this institutional study, 36 eyes of 36 patients with amblyopia (AE), 36 fellow eyes without amblyopia (FE), and 32 eyes of 32 normal subjects (NE) were included. RNFL, GCC and macular thickness measurements were performed with RS-3000 OCT Retina Scan (Nidek Inc CA. USA).RESULTS:The mean global thicknesses of the RNFL were 113.22±21.47, 111.57±18.25, 109.96±11.31µm in the AE, FE, and NE, respectively. There was no statistically significant difference for mean global RNFL thickness among the eyes (P=0.13). The mean thicknesses of the macula were 258.25±18.31, 258.75±19.54, 248.62±10.57μm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of macula among the eyes (P=0.06). The GCC was investigated into two parts:superior and inferior. The mean thicknesses of superior GCC were 102.57±13.32, 103.32±10.64, 100.52±5.88μm in the AE, FE, and NE, respectively. The mean thicknesses of inferior GCC were 103.82±12.60, 107.82±12.33, 105.86±10.79μm in the AE, FE and NE, respectively. There was no statistically significant difference for thickness of superior and inferior GCC between the eyes (P=0.63, P=0.46).CONCLUSION:The macular thicknesses of AE and FEwere greater than the NE, although it was not statistically significant. Amblyopia does not seem to have a profound effect on the RNFL, macula and GCC.     

Macular and peripapillary retinal nerve fibre layer thickness in adults with amblyopia

Objective

To evaluate macular and peripapillary retinal nerve fiber layer (RNFL) thickness in amblyopic eyes compared to the fellow eye.

Design

Cross-sectional study.

Participants

30 patients (60 eyes) older than 18 years of age with amblyopia.

Methods

Inclusion criteria included individuals older than 18 years, amblyopia, and best-corrected visual acuity (BCVA) ≤20/40. A complete medical history was taken and an eye examination carried out. Optical coherence tomography (OCT) was carried out on both eyes of all patients. Exclusion criteria included intraocular pressure (IOP) >23 mm Hg and eye pathology that may affect OCT measurements. The primary outcome measures were foveal thickness and average peripapillary RNFL thickness, which were compared using a paired t test. Quadrants in peripapillary scans and concentric rings in macular scans were analyzed.

Results

The average age was 56 years (range = 33–82 years). Visual acuity ranged from 20/40 to 20/4000 (mean = 20/275). The average peripapillary RNFL thickness was 90.6 μm (SD = 9.6 μm) in the amblyopic eye and 90.1 μm (SD = 12.1 μm) in the fellow eye (p = 0.64). The average macular thickness in amblyopic eyes was 260.1 μm (SD = 32.0 μm), and 254.7 μm (SD = 32.5 μm) in fellow eyes (p = 0.10). No statistical difference existed between peripapillary quadrants or macular concentric rings. These differences were smaller when the strabismic amblyopes were isolated.

Conclusions

There does not seem to be a difference in peripapillary RNFL or macular thickness between the amblyopic eye and fellow eye.     

Pattern electroretinogram association with spectral domain-OCT structural measurements in glaucoma

Purpose

To describe the association between pattern electroretinogram (PERG) amplitude and spectral domain-optical coherence tomography (SD-OCT) macular thickness, retinal nerve fibre layer (RNFL) thickness and optic disc topography measurements.

Subjects and methods

Both eyes (n=132) of 66 glaucoma patients (mean age=67.9 years) enroled in the University of California, San Diego, CA, USA, Diagnostic Innovations in Glaucoma Study (DIGS) were included. Eyes were tested with PERG (Glaid PERGLA, Lace Elettronica, Pisa, Italy), RTVue SD-OCT (Optovue Inc., Fremont, CA, USA) GCC, and NHM4 protocols on the same day. Of the 66 enroled patients, 43 had glaucoma defined by repeated abnormal standard automated perimetry (SAP) results in at least one eye and 23 were glaucoma suspects defined by a glaucomatous-appearing optic disc by physicians'' examination in at least one eye and normal SAP results in both eyes. Associations (R ²) were determined between PERG amplitude (μV) and SD-OCT macular ganglion cell complex (GCC) thickness (μm), macular thickness (μm), macular outer retinal thickness (macular thickness minus GCC thickness) (μm), RNFL thickness (μm), neuroretinal rim area (mm²), and rim volume (mm³).

Results

PERG amplitude was significantly associated with GCC thickness (R ²=0.179, P<0.001), RNFL thickness (R ²=0.174, P<0.001), and macular thickness (R ²=0.095, P<0.001). R ² associations with other parameters were not significant (all P>0.624). Significant associations remained for GCC and average RNFL thickness when age and intraocular pressure at the time of testing were included in multivariate models (both P≤0.030).

Conclusions

PERG amplitude is significantly (but weakly) associated with macular GCC thickness, RNFL thickness, and macular thickness. The lack of association between PERG amplitude and macular outer retinal thickness supports previous results, possibly suggesting that that the PERG is driven primarily by retinal ganglion cell (inner retinal) responses.     

Optical coherence tomography findings in spinocerebellar ataxia-3

Purpose

To report optical coherence tomography (OCT) findings in order to detect subclinical alterations of the afferent visual pathways in spinocerebellar ataxia 3 (SCA-3).

Patients and methods

Nine genetically confirmed patients (18 eyes) were evaluated with a complete ophthalmologic examination including visual acuity, colour vision, visual field test, and retinal nerve fibre layer (RNFL) and macular thickness with OCT Cirrus HD. A neurological examination was performed and the Scale for the Assessment and Rating of Ataxia (SARA score) was determined in all patients.

Results

The mean RNFL thickness was 77.39 microns, standard deviation (SD) was ±5.93. In 15 eyes (83.33%), the mean RNFL thickness was lower than the population average considering age and sex. In 10 cases, there was a reduction of the RNFL thickness in the superior sector, eight in the inferior and four in the nasal. Temporal sector RNFL thickness was preserved in all eyes. RNFL thickness was inversely correlated to SARA score (r=−0.64, P=0.012). The mean macular thickness was 252.61 microns, SD±22.80, being inferior respecting average population in only two eyes (11.11%). In four patients, (eight eyes) OCT studies were performed during a mean follow-up of 14.25 months, and in five eyes (62.50%) there was a mild trend to a RNFL thickness decrease in this period.

Conclusion

A mild and progressive decrease in RNFL thickness can be observed in SCA-3 patients. A negative correlation exists between an anatomic marker (RNFL thickness) and a clinical severity scale (SARA score); thus, RNFL thickness could be considered as a promising biomarker of the disease.     

Intravitreal bevacizumab for pediatric exudative retinal diseases

Purpose

To detect if intravitreal bevacizumab can reduce retinal exudation, improve visual and anatomical outcomes, and facilitate the treatment in various pediatric exudative retinal diseases.

Patients and methods

Prospective, non-randomized, case series of nine eyes of pediatric exudative retinal diseases less than 18 years old which included six eyes with juvenile diabetic retinopathy, two eyes in children with Coats’ disease, and one eye with myopic choroidal neovascular membrane (CNV). All eyes received only intravitreal bevacizumab injection 1.25 mg/0.05 ml as the primary treatment. The need for adjuvant ablative procedures, including laser photocoagulation or cryotherapy, were performed and recorded. The need for supplementary intravitreal bevacizumab injection was recorded. The changes in pre- and post-operative best-corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded. Serial optical coherent tomography (OCT) and fundus flourescein angiography (FFA) were performed to follow treatment efficacy.

Results

The study included 19 eyes of 11 patients with age equal to or less than eighteen years with exudative retinal diseases including type I DM (n = sixteen eyes), Coats’ disease (n = 2 eyes), and due to myopic CNV (n = 1 eye). Mean pre-injection log MAR for all was 0.605 ± 0.174 and mean post-injection for all log MAR was 0.284 ± 0.247. While Mean pre-injection log MAR for DR and myopic CNV patients was 0.576 + 0.152 SD and mean post-injection log MAR for DR and myopic CNV patients was 0.229 + 0.189 at one year. Serial OCT measurements showed that mean CMT for all eyes was 355.8 ± 35.3 μm SD at baseline, which was decreased to 222.42 + 26.2 μm SD. The two eyes of Coats’ disease needed another two supplementary intravitreal bevacizumab injections. No ocular or systemic complications related to bevacizumab were noted during the entire course of follow-up.

Conclusion

Intravitreal bevacizumab appears to be a well-tolerated treatment for pediatric age group with various exudative retinal diseases. It has the potential as an adjuvant therapy for ablative procedures to improve final visual and anatomical outcome.     

Macular findings on optical coherence tomography in cat-scratch disease neuroretinitis

Purpose

To describe the macular findings on optical coherence tomography (OCT) in patients with cat-scratch disease (CSD) neuroretinitis.

Methods

Medical records of all patients diagnosed with CSD neuroretinitis at the Tel Aviv Medical Center between April 2006 and May 2010 were retrospectively reviewed. All patients underwent Stratus OCT macular examination.

Results

Eight eyes of seven patients with confirmed CSD neuroretinitis, (mean age 33±9.9 years, range 6–48 years) were included in the study. All patients presented clinically with optic nerve swelling and macular edema or macular exudates. OCT demonstrated flattening of the foveal contour, thickening of the neurosensory retina, and accumulation of subretinal fluid (SRF) in all studied eyes. Retinal exudates appeared as multiple hyper-reflective foci in the outer plexiform layer. The average central macular thickness was 460 μm (range 170–906 μm) and the average maximal retinal thickness was 613 μm (range 387–1103 μm), at presentation. The macula appeared normal on repeated exams during follow-up.

Conclusion

Similar OCT findings were demonstrated in patients with CSD neuroretinitis. SRF was found in all eyes, although was not visible on clinical examination or fluorescein angiography. OCT may be used as an adjunct imaging tool in the diagnosis and follow-up of patients with CSD neuroretinitis.     

Thicknesses of macular retinal layer and peripapillary retinal nerve fiber layer in patients with hyperopic anisometropic amblyopia

This prospective study was performed to measure the macular and the peripapillary retinal nerve fiber layer (RNFL) thicknesses using optical coherence tomography (OCT) in patients with anisometropic amblyopia. Thirty-one patients with hyperopic anisometropic amblyopia were included. The macular retinal thickness and the peripapillary RNFL thickness were measured using OCT. The mean refractive error was +3.71 diopters (D) and +1.00 D, the mean macular retinal thickness was 252.5 microm and 249.7 microm, and the mean RNFL thickness was 115.2 microm and 109.6 microm, inthe amblyopic eye and the normal eye, respectively. OCT assessment of RNFL thickness revealed a significantly thicker RNFL in hyperopic anisometropic amblyopia (P=0.019), but no statistically significant difference was found in macular retinal thickness (P>0.05). In conclusion, the amblyopic process may involve the peripapillary RNFL, but not the macula. However, further evaluation is needed.     

Macular and peripapillary retinal nerve fibre layer thickness in patients with cyanotic congenital heart disease

Purpose

To evaluate macular and retinal nerve fibre layer (RNFL) measurements in patients with cyanotic congenital heart disease (cCHD) using spectral domain optical coherence tomography (OCT).

Patients and methods

Thirty patients with cCHD (18 females and 12 males, mean age 10.9 years) and 60 healthy controls (35 females and 25 males, mean age 11.2 years) underwent complete ophthalmologic examination and OCT measurements of macular and peripapillary RNFL thickness.

Results

Patients with cCHD had significantly thinner measurements in all macular subfields compared with healthy controls (P<0.001). There was no significant difference in peripapillary RNFL thickness between the two groups, with the exception of the upper quadrant, for which thickness measurements were higher in patients with cCHD (P=0.021).

Conclusions

Patients with cCHD showed a significant decrease in macular thickness and a thickened superior quadrant RNFL thickness when compared with healthy controls. This may represent the damage caused by the effect of hypoxia.     

Discriminating ability of spectral domain optical coherence tomography in different stages of glaucoma

Purpose

To determine the discriminating ability of retinal nerve fiber layer (RNFL) thickness measured with spectral-domain optical coherence tomography (SD-OCT) in different stages of glaucoma.

Patients and methods

Thirty normal, 150 glaucomatous eyes were included. Glaucomatous eyes were graded into early, moderate and severe stages according to one of the global indices called visual field index (VFI). Complete ophthalmic examination, white on white perimetry and SD-OCT were done for all patients. RNFL thickness of quadrants and average thickness were recorded. Area under receiver operating characteristic curves (AUCs) were used to assess the performance of OCT parameters.

Results

Average, inferior and superior RNFL thickness were the best parameters to discriminate normal from early glaucoma (AUC: 0.91–86), early from moderate (AUC: 0.77–0.70) and moderate from severe (AUC: 0.85–83). Average RNFL loss was 18% in early glaucoma, 28% in moderate glaucoma and 41% in severe glaucoma. Early damage tends to be focal and in the lower quadrant. A significant correlation was detected between mean VFI and mean RNFL loss. Glaucoma was restaged according to average RNFL loss into early: ⩾97.5 μ, moderate: <97.5–72.5 μ and severe: <72.5 μ.

Conclusion

RNFL thickness measured with SD-OCT could discriminate the three stages of glaucoma. RNFL loss can be correlated to visual field loss. Future OCT-based staging of glaucoma, adjunctive to perimetry is possible.     

Cystoid Macular Edema after Complicated Cataract Surgery Resolved by an Intravitreal Dexamethasone 0.7-mg Implant

Purpose

To report the effective treatment of cystoid macular edema (CME) following complicated cataract surgery (resulting in Irvine-Gass syndrome) with a dexamethasone 0.7-mg (Ozurdex^®) intravitreal implant.

Methods

An interventional case report with optical coherence tomography (OCT) scans.

Results

An 83-year-old Caucasian woman was suffering from CME following complicated cataract surgery on her left eye. She had undergone 3 intravitreal injections of dexamethasone 0.4 mg in the 3 months following the surgery without any improvement of visual function. Seven months after the cataract surgery, she received a single intravitreal injection of dexamethasone 0.7 mg (Ozurdex). Four weeks following the injection, her best-corrected visual acuity improved from 0.3 to 0.8. CME resolved with a reduction of central retinal thickness from 393 μm pre-Ozurdex injection to 212 μm post-Ozurdex injection, as measured by OCT scan.

Conclusion

Dexamethasone 0.7 mg (Ozurdex) has proven to be an effective treatment option in retinal vein occlusion and non-infectious uveitis. It can also be considered as off-label treatment in Irvine-Gass syndrome.Key Words: Cystoid macular edema, Irvine-Gass syndrome, Dexamethasone 0.7 mg, Ozurdex^®     

Foveal Thickness between Stratus and Spectralis Optical Coherence Tomography in Retinal Diseases

Purpose

To compare the foveal thickness (FT) parameters measured by Stratus optical coherence tomography (OCT) and Spectralis OCT in various retinal diseases and to construct conversion formulas between the two types of OCT devices.

Methods

We examined 366 consecutive patients (475 eyes) with retinal diseases and 13 normal controls (13 eyes). The patients were categorized into eight retinal disease groups. The mean amount and distribution of foveal thickness differences (FTD) measured by Stratus and Spectralis OCT were determined, and conversion formulas were constructed for Stratus OCT FT from Spectralis OCT FT for each retinal disease group.

Results

Among retinal diseases, the mean FTD was significantly larger in exudative age-related macular degeneration (AMD) patients (mean ± SD, 94.0 ± 55.0 µm) compared to normal subjects (66.2 ± 11.7 µm; p < 0.0001). The proportion of eyes with a mean FTD outside 1.96 standard deviations of normal subject FTD was greatest in the exudative AMD (50.0%) group and smallest in the macular hole (18.2%) group. The predicted FTs obtained through the conversion formulas showed lower variance than the actual FTD values, especially in the exudative AMD group. The prediction line for exudative AMD deviated most from that of normal subjects.

Conclusions

FTD shows diverse values and variances among various retinal diseases, especially in exudative AMD, which indicates that Stratus OCT FT cannot be predicted from Spectralis OCT FT by FTD value alone. We constructed statistically significant conversion formulas, which provided more reliable methods to predict Stratus OCT-measured FT from Spectralis OCT measurements for different retinal disease groups.     

Evaluation of the Response to Ranibizumab Therapy following Bevacizumab Treatment Failure in Eyes with Diabetic Macular Edema

Background/Aims

Bevacizumab and ranibizumab are routinely used to treat diabetic macular edema (DME). We aim to evaluate the usefulness of switching to ranibizumab therapy following bevacizumab treatment failure in eyes with DME.

Methods

We performed a retrospective analysis of a consecutive group of patients with DME who received ranibizumab injections following the failure of bevacizumab injections. The injections were delivered following a pro re nata protocol every 4–6 weeks. The data collected included demographics, systemic and ophthalmic findings, as well as the central subfield thickness according to spectral-domain OCT.

Results

Eight eyes (5 patients) were included in the study. The median number of bevacizumab injections prior to the switch to ranibizumab was 4, and the median number of ranibizumab injections during the study was 2. The mean follow-up period was 541 ± 258 days. The mean central retinal thickness (CRT) (±SEM) was 539 ± 75 μm before the initiation of bevacizumab treatment, and 524 ± 43 μm after the last bevacizumab injection (p = 0.7). It reduced to 325 ± 26 μm following the ranibizumab injections (p = 0.0063). The best-corrected visual acuity (BCVA) improved in 4 eyes and remained stable in 4 eyes following the ranibizumab injections.

Conclusion

A ranibizumab therapy was effective in reducing the CRT in eyes that failed bevacizumab therapy. A BCVA improvement can also occur in these eyes. Switching between anti-vascular endothelial growth factor compounds may be beneficial in eyes with DME.Key Words: Ranibizumab, Bevacizumab, Diabetic macular edema, Treatment failure     

The Effect of Pattern Scan Laser Photocoagulation on Peripapillary Retinal Nerve Fiber Layer Thickness and Optic Nerve Morphology in Diabetic Retinopathy

Purpose

To evaluate the effect of pattern scan laser (PASCAL) photocoagulation on peripapillary retinal nerve fiber layer (RNFL) thickness, central macular thickness (CMT), and optic nerve morphology in patients with diabetic retinopathy.

Methods

Subjects included 35 eyes for the PASCAL group and 49 eyes for a control group. Peripapillary RNFL thickness, cup-disc area ratio and CMT were measured before PASCAL photocoagulation and at 2 and 6 months after PASCAL photocoagulation in the PASCAL or control groups.

Results

The average RNFL thickness had increased by 0.84 µm two months after and decreased by 0.4 µm six months after PASCAL photocoagulation compared to baseline, but these changes were not significant (p = 0.83, 0.39). The cup-disc area ratio was unchanged after PASCAL photocoagulation. CMT increased by 18.11 µm (p = 0.048) at two months compared to baseline thickness, and partially recovered to 11.82 µm (p = 0.11) at six months in the PASCAL group.

Conclusions

PASCAL photocoagulation may not cause significant change in the peripapillary RNFL thickness, CMT, and optic nerve morphology in patients with diabetic retinopathy.