Retinal and optic nerve evaluation by optical coherence tomography in adults with obstructive sleep apnea–hypopnea syndrome (OSAHS)

Objective

To assess the peripapillary retinal nerve fiber layer (RNFL) thickness, optic nerve head (ONH) morphologic parameters, and macular thickness and volume in patients affected by obstructive sleep apnea–hypopnea syndrome (OSAHS).

Methods

This prospective, observational case-control study consisted of 96 eyes of 50 OSAHS patients (mean age of 50.9?±?12.4 years, best-corrected visual acuity ≥20/20, refractive error less than 3 spherocylindrical diopters, and intraocular pressure <21 mmHg) who were enrolled and compared with 64 eyes of 33 age-matched controls. Peripapillary RNFL thickness, ONH parameters, macular thickness and volume were measured by optical coherence tomography (OCT).

Results

OSAHS patients showed a significant reduction of the nasal quadrant RNFL thickness (74.7?±?15.8 μm) compared with those values observed in control patients (81.1?±?16.6 μm, p?=?0.047, Student's t-test). No differences in peripapillary RNFL thickness were observed when dividing the OSAHS group in accordance with disease severity. Vertical integrated rim area (VIRA) (0.67?±?0.41 mm³ in OSAHS vs 0.55?±?0.29 mm³ in controls; p?=?0.043, Student's t-test), horizontal integrated rim width (HIRW) (1.87?±?0.31 mm² in OSAHS vs 1.8?±?0.25 mm² in controls; p?=?0.039, Student's t-test) and disc area (2.74?±?0.62 mm² in OSAHS vs 2.48?±?0.42 mm² in controls; p?=?0.002, Student's t-test) showed significant differences, all of them being higher in the OSAHS group. Severe OSAHS had significant higher disc area (2.8?±?0.7 mm²) than controls (2.5?±?0.4 mm²; p?=?0.016, ANOVA test). Temporal inner macular thickness was significantly higher in mild–moderate OSAHS patients (270?±?12 μm) than in severe OSAHS patients (260?±?19 μm; p?=?0.021, ANOVA test).

Conclusions

OSAHS patients showed decreased peripapillary nasal RNFL thickness, and increased ONH area and volume parameters when they were evaluated by OCT. These findings suggest that neuronal degeneration might be present in the retina of OSAHS patients, as previously observed in some neurodegenerative disorders     

Retinal vessel diameter in normal-tension glaucoma patients with asymmetric progression

Purpose

To investigate the longitudinal changes in the central retinal vessel diameter in asymmetric progressive normal-tension glaucoma (NTG) patients.

Methods

This study included 27 patients with bilateral NTG without any systemic vascular disease who showed glaucomatous progression in one eye at the mean follow-up of 24.3 months (range, 18–29 months). Progression was determined by the development of new retinal nerve fiber layer (RNFL) defects or widening of pre-existing defects on red-free RNFL photographs. The central retinal arteriolar equivalent (CRAE) and the central retinal venular equivalent (CRVE) were measured at baseline and at the mean follow-up of 24.3 months. We classified the eyes of each patient as either progressed or stable eyes, and compared the differences and changes in the CRAE and CRVE.

Results

No significant inter-eye difference was observed at baseline in the mean CRAE (167.5?±?22.2 μm vs. 168.2?±?15.5 μm, p?=?0.809) and in the mean CRVE (276.3?±?18.2 μm vs. 281.6?±?21.9 μm, p?=?0.267) between the progressed and stable eyes. There were significant changes in CRAE in the progressed eyes between baseline and 2 years after baseline (from 167.5?±?22.2 μm to 146.9?±?18.0 μm, p?p?=?0.084).

Conclusions

In our series of NTG patients with asymmetric progression, central retinal artery diameter decreased over time in the progressed eyes, whereas no significant decrease in the central retinal artery diameter was seen in the stable eyes.     

Pattern ERG and RNFL thickness in hypertensive eyes with normal blue-yellow visual field

Purpose

To evaluate the transient pattern electroretinogram (t-PERG) and the retinal nerve fiber layer (RNFL) thickness in eyes with ocular hypertension (OH) and normal short-wavelength automated perimetry (SWAP).

Methods

In 26 patients with bilateral OH with normal SWAP, and in 26 age and sex matched healthy controls, t-PERG recording and RNFL thickness measurement were performed. Mean deviation (MD) and pattern standard deviation (PSD) of a reliable full threshold 24-2 SWAP were considered. RNFL thickness was determined by OCT3. Monocular PERG were recorded by using a black and white checkerboard pattern (check size 0.9°, contrast 100 %, mean luminance 80 cd/m2) generated on a monitor and reversed in contrast (four reversals per second, 2 Hz) at a distance of 70 cm. Patients had optimal correction at viewing distance; no mydriatic or miotic eye drops were used. Silver/silver chloride skin electrodes were placed over the lower eyelids in the stimulated eye (active electrode) and in the patched eye (reference electrode); ground electrode was in the Fpz scalp. Peak-to peak amplitude of P50 (N35-P50) and N95 (P50-N95) waves, and implicit time of P50, were considered.

Results

Compared to controls, in OH eyes, a reduction of N35-P50 amplitude (2.86?±?1.49 vs. 3.77?±?1.08 microvolts, ?24.1 %, t-test p?=?0.015), of average RNFL thickness (88?±?11 vs. 96?±?10 μm, ?9.5 %, t-test p?=?0.002), and of RNFL thickness in superior (p?=?0.015) and inferior quadrant (p?<?0.001), were found. Multivariate analysis showed that in OH eyes, N35-P50 amplitude was inversely related to intraocular pressure (IOP) (p?=?0.001); no correlation was found between N35-P50 amplitude and MD, PSD, CCT or RNFL thickness.

Conclusions

In OH eyes, both PERG and RNFL thickness changes occur in hypertensive eyes with undamaged SWAP; the correlation of PERG amplitude with IOP, but not with RNFL thickness, suggests that such PERG changes are an effect of the IOP on retinal ganglion cells, rather than a sign of their loss.     

Photoreceptor inner and outer segment layer thickness in multiple evanescent white dot syndrome

Purpose

To evaluate the photoreceptor inner and outer segment layer thickness in eyes with MEWDS.

Design

Prospective, non-comparative, observational case series. The follow-up duration was 4 months.

Methods

Four women were diagnosed with unilateral MEWDS. The ages of the patients were 25, 24, 35, and 40 years. The retinal microstructure was assessed by spectral-domain optical coherence tomography (SD-OCT). The thickness of the photoreceptor inner (IS) and outer (OS) segments and sum of them (IS + OS) at the fovea were analyzed.

Results

The visual acuity was reduced in three of four eyes at the acute phase. SD-OCT showed that the border of IS and OS (IS/OS) line and the cone outer segment tips (COST) line in the macula area were not detected in all four eyes. The IS + OS thickness was 50.3?±?5.6 μm and that of the healthy fellow eyes was 73.5?±?7.0 μm (n?=?4 eyes). The thickness of the IS was 27.8?±?2.6 μm and that of the OS was 45.8?±?7.3 μm. In all eyes, there was a spontaneous improvement of the visual acuity. SD-OCT showed a recovery of only the IS/OS line in the macular area, but the COST line was not visible in three cases. The mean IS + OS thickness increased to 56.0?±?7.9 μm (n?=?4), IS?=?26.0?±?2.0 μm (n?=?3), and OS?=?30.1?±?8.7 μm (n?=?3) in the early recovery phase, and to 64.8?±?9.3 μm (n?=?4), IS?=?28.5?±?1.7 μm (n?=?4), and OS?=?36.3?±?7.9 μm (n?=?4) in the late recovery phase. The mean inner and outer segment thickness remained unchanged in the fellow eyes.

Conclusion

Eyes with MEWDS have changes in the photoreceptor microstructures. The change in the IS + OS thickness during the natural recovery course might be due to an increase in the OS length.     

Baseline thickness of macular ganglion cell complex predicts progression of visual field loss

Background

Previous studies reported that the thickness of the macular ganglion cell complex (mGCC) showed good diagnostic ability for detecting glaucoma. However, its impact on the progression of visual field loss in primary open angle glaucoma (POAG) is unknown. The purpose of this study was to assess whether baseline mGCC thickness is associated with the progression of visual field loss in POAG.

Methods

Fifty-six patients with POAG were included in the study. All patients were followed for more than 2 years after baseline optical coherence tomography (OCT) measurements. They had at least five reliable Humphrey visual field tests with 30–2 Swedish Interactive Threshold Algorithm standard tests during the follow-up period. The subjects were divided into two groups according to the slope of the mean deviation (MD): the fast progression group (MD slope < ?0.4 dB/y) and the slow progression group (MD slope ≥ ?0.4 dB/y). Factors compared between the groups were as follows: age, baseline intraocular pressure (IOP), mean IOP during the follow-up, refraction, baseline MD, pattern standard deviation (PSD), and baseline OCT measurements.

Results

There were no significant differences between the two groups in age, baseline IOP, mean IOP during the follow-up, refraction, baseline MD or PSD, average thickness of retinal nerve fiber layer (RNFL), or disc parameters. However, the baseline mGCC thickness (average and inferior hemifield) was significantly thinner in the fast progression group than in the slow progression group (74.0?±?7.2 μm vs. 80.3?±?8.6 μm; 68.0?±?6.6 μm vs. 78.2?±?11.6 μm, respectively). Moreover, global loss volume and focal loss volume, which are parameters of mGCC, showed significantly higher rates in the fast progression group than in the slow progression group. In multivariate analysis, only mGCC thickness of the inferior hemifield was associated with disease progression (P?=?0.007).

Conclusions

Baseline mGCC thickness can be predictive of progressive visual field loss in patients with POAG.     

Relationship between corneal hysteresis and optic nerve parameters measured with spectral domain optical coherence tomography

Background

Corneal hysteresis (CH) has been associated with visual field damage in glaucoma and is related to the velocity of perimetric glaucoma progression. We undertook this investigation to determine whether CH is associated with structural markers of glaucoma damage on spectral domain optical coherence tomography (SD-OCT).

Methods

In this retrospective study, 131 patients under glaucoma evaluation were evaluated with SD-OCT (Cirrus; Carl Zeiss Meditec, Dublin, CA) and had CH measurements with the ocular response analyzer (Reichert, Inc., Buffalo, NY). Pearson and partial correlation adjusting for age were preformed to examine the association between CH and variables of interest. Generalized estimating equations were used to construct simple and multiple linear models.

Results

While Pearson correlations were modest overall, CH best correlated with mean deviation (MD; r?=?0.19) followed by average retinal nerve fiber layer (RNFL) thickness (r?=?0.18) and vertical cup to disc ratio (r?=??0.11) in the open angle glaucoma group. In univariable models, CH varied as a function of MD (ß?=?0.1, 95 % CI 0.03, 0.1; p?<?0.001) and of average RNFL thickness (ß?=?0.2, 95 % CI 0.1, 0.4; p?=?0.001). In a multivariable analysis including MD, age, average RNFL thickness, and glaucoma status, MD (p?=?0.001) and age (p?<?0.001) retained significant associations with CH.

Conclusions

In patients under evaluation and treatment for glaucoma, CH was more closely related to visual field MD than to structural markers of glaucoma damage as measured by SD-OCT.     

Overestimation of subfoveal choroidal thickness by measurement based on horizontally compressed optical coherence tomography images

Purpose

To measure the difference in subfoveal choroidal thickness between 1:1 pixel (horizontally compressed) images and 1:1 micron images in age-related macular degeneration.

Methods

This study included 122 eyes from 122 patients diagnosed with age-related macular degeneration. Choroidal thickness was measured using enhanced-depth imaging optical coherence tomography. The measurement line was drawn as a perpendicular line between Bruch’s membrane and the chorio-scleral interface. The thickness was compared between measurements based on a 1:1 pixel image and a 1:1 micron image. Eyes with a straight vertical measurement line and oblique measurement line were classified into vertical measurement group and oblique measurement group, respectively. Intra-group comparisons of subfoveal choroidal thickness measurements based on the 1:1 pixel images and the 1:1 micron images were performed for the two groups.

Results

The mean subfoveal choroidal thicknesses measured on the 1:1 pixel images and the 1:1 micron images were 232.3?±?106.4 μm and 228.9?±?108.1 μm, respectively (p?=?0.003). In the vertical measurement group (86 eyes), the mean subfoveal choroidal thickness was 226.3?±?109.9 μm and 225.4?±?112.0 μm, respectively (p?=?0.423). In the oblique measurement group (36 eyes), the thickness was 246.5?±?97.3 μm and 237.5?±?98.9 μm, respectively (p?<?0.001).

Conclusions

Significant overestimation of the subfoveal choroidal thickness was noted when it was measured on a 1:1 pixel image. This finding suggests that the measurement of choroidal thickness should be performed based on a 1:1 micron image, especially if the measurement line is not vertical.     

Correlation between early retinal nerve fiber layer loss and visual field loss determined by three different perimetric strategies: white-on-white,frequency-doubling,or flicker-defined form perimetry

Purpose

To compare the significance of white-on-white standard automated perimetry (SAP), matrix frequency doubling technology (FDT), and flicker-defined form perimetry (FDF) for early detection of nerve fiber layer loss in early glaucoma patients.

Methods

Fifty-one healthy controls and 40 patients with early glaucomatous nerve fiber loss were enrolled in this study. Patients had retinal nerve fiber layer (RNFL) imaging and visual field testing by SAP, FDT matrix, and FDF perimetry at the same visit. Visual field defects were confirmed with two or more consecutive examinations by the same types of perimetry. Significant retinal nerve fiber layer loss and thus early glaucoma was defined with the reference to the RNFL thickness deviation map. The sensitivity, specificity, correlation, MD (mean deviation) and PSD (pattern standard deviation) visual field indexes, and area under the receiver operating characteristic curve (AUC) of MD and PSD of the perimetries were compared.

Results

There was a significant difference in nerve fiber layer thickness between healthy patients (97.7 ± 1.34 μm and patients with early glaucoma (84.1 ± 1.58 μm) (p?p?0.6. AUCs of PSD were not reliable in all of the three VF devices.

Conclusions

The sensitivity for detection of RNFL loss in early glaucoma seems to be higher in FDF and FDT matrix than SAP perimetry, while specifity was highest in SAP. Thus, simultaneous performance of FDF/FDT matrix and SAP perimetry seems beneficial for the correct diagnosis of early glaucoma in patients.     

Novel use of 3T MRI in assessment of optic nerve volume in glaucoma

Purpose

To measure optic nerve (ON) volume using 3 T magnetic resonance imaging (MRI), to correlate ON volume with retinal nerve fiber layer (RNFL) thickness, and to determine the viability of MRI as an objective tool in distinguishing glaucoma severity.

Methods

In this cross-sectional study, 30 severe glaucoma patients, 30 mild glaucoma patients and 30 age-matched controls were recruited. All subjects underwent standard automated perimetry, RNFL analysis and 3 T MRI examinations. Glaucoma patients were classified according to the Hodapp–Anderson–Parish classification. Pearson’s correlation coefficient was used to correlate ON volume with RNFL, and receiver operating curve (ROC) analysis was performed to determine the sensitivity and specificity of ON volume in detecting glaucoma severity.

Results

Optic nerve volume was significantly lower in both the left and right eyes of the severe glaucoma group (168.70?±?46.28 mm³; 167.40?±?45.36 mm³) than in the mild glaucoma group (264.03?±?78.53 mm³; 264.76?±?78.88 mm³) and the control group (297.80?±?71.45 mm³; 296.56?±?71.02 mm³). Moderate correlation was observed between: RNFL thickness and ON volume (r?=?0.51, p <0.001), and in mean deviation of visual field and optic nerve volume (r?=?0.60, p?<?0.001). ON volume below 236 mm³ was 96 % sensitive and 80 % specific for the detection of severe glaucoma.

Conclusions

MRI measured optic nerve volume is a reliable method of assessing glaucomatous damage beyond the optic nerve head. A value of 236 mm³ and below can be used to define severe glaucoma.     

Relationship between disc margin to fovea distance and central visual field defect in normal tension glaucoma

Background

To investigate the relationship between ocular geometric factors, including temporal disc margin to fovea distance (DFD) measured by optic disc stereophotography (ODP) and central visual field (VF) defect, in normal-tension glaucoma (NTG) patients.

Methods

This retrospective, single-center, cross-sectional study included 88 eyes of 88 NTG patients with mild VF defects (MD?>??6.0 dB). NTG patients were divided into two groups according to VF tests: central VF-invading and central VF-sparing groups. Optic nerve head (ONH) parameters including disc dimensions, peripapillary atrophy (PPA), and DFD were obtained by ODP, and retinal nerve fiber layer (RNFL) thickness was measured by Stratus optical coherence tomography (OCT).

Results

In the invading group, DFD was shorter (3.642?±?0.401 mm) than in the sparing group (3.877?±?0.278 mm; p?=?0.002). The sparing group had more vertically oval ONH (p?=?0.023) and wider temporal PPA width (p?=?0.031). The RNFL thickness in the invading group was thinner in the temporal and inferior quadrants, but thicker in the superior quadrant than that of the sparing group. In a multiple linear regression analysis, DFD was the only geometric factor associated with degree of central VF involvement (p?=?0.002). DFD was positively correlated with temporal RNFL thickness in the sparing group (r?=?0.484, p?<?0.001) but not in the invading group (r?=??0.080, p?=?0.631).

Conclusions

Eyes with a shorter DFD should be monitored carefully because central VF involvement appears to be related to shorter DFD in NTG patients with mild VF defects.     

Comparison of dynamic contour tonometry and Goldmann applanation tonometry in relation to central corneal thickness in primary congenital glaucoma

Background

To compare intraocular pressure (IOP) measurements obtained with dynamic contour tonometer (DCT) and Goldmann applanation tonometer (GAT), and to investigate their relationship to central corneal thickness (CCT) in primary congenital glaucoma (PCG) eyes.

Methods

Thirty-one eyes of 31 PCG patients (25.7?±?7.2 years old) were examined. PCG was defined as elevated IOP, enlarged corneal diameter (buphthalmos), Haab’s striae and abnormal findings at gonioscopy. The mean of three measurements of GAT, DCT (quality scores 1 and 2), and CCT were obtained and assessed for agreement by means of Bland–Altman plot and for Spearman correlation test.

Results

Mean CCT was 534?±?72.3 μm (range: 430 to 610 μm). Mean IOP measurements were 15.1?±?4.2 mmHg (range: 5.5 to 22.7 mmHg) for DCT and 14.5?±?5.6 mmHg (range: 7.0 to 34.0 mmHg) for GAT (P?=?0.244). Spearman correlation tests showed that IOP difference (DCT ? GAT) was not correlated with CCT (r ²?=?0.023, P?=?0.417). IOP measurements by DCT were weakly but statistically correlated with those obtained with GAT (r²?=?0.213, P?=?0.0089). Bland–Altman analysis revealed poor agreement between DCT and GAT readings, considering the 95 % confidence intervals of ±10.45 mmHg.

Conclusions

The differences between DCT and GAT readings were not influenced by CCT in this series of patients. Considering the weak correlation and the poor agreement observed between GAT and DCT measurements and that they both may be affected by corneal biomechanical changes, these methods should not be used interchangeably, and may possibly give no meaningful IOP values in PCG patients.     

Bimonthly injections of ranibizumab for age-related macular degeneration

Purpose

To evaluate the efficacy of bimonthly intravitreal injections of ranibizumab for age-related macular degeneration (AMD) and polypoidal choroidal vasculopathy (PCV) in a pilot study.

Methods

This study was a prospective, interventional case series. Thirty eyes of 30 patients received prospectively at least three bimonthly intravitreal injections of ranibizumab (0.5 mg/0.05 ml) without loading doses. The best-corrected visual acuity (BCVA) and the central retinal subfield thickness (CRST) were measured before and monthly after the injections.

Results

Twenty-eight patients received the three planned injections; one patient refused the third injection, one patient did not receive the third injection because blood pressure was raised, and one patient received a rescue injection at month 5 because of increased retinal thickness. The mean logarithm of the minimum angle of resolution (logMAR) BCVA was 0.44?±?0.37 before treatment and significantly improved to 0.25?±?0.34 at month 6 (p?p?p?=?0.005). The mean CRST was 360?±?110.8 μm before treatment and decreased significantly to 249?±?57.0 μm at month 12 (p?=?0.025).

Conclusions

Bimonthly injections of ranibizumab may be effective for treating AMD and PCV.     

Comparison of ganglion cell and retinal nerve fiber layer thickness in primary open-angle glaucoma and normal tension glaucoma with spectral-domain OCT

Background

The aim of this study was to evaluate the macular thickness (MT), ganglion cell complex (GCC), and circum-papillary retinal nerve fiber layer (RNFL) thickness in primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) with spectral domain optical coherence tomography (SD-OCT).

Methods

A total of 169 subjects were enrolled: 52 normal subjects, 61 with POAG, and 56 with NTG. Spectral-domain optical coherence tomography (SD-OCT) was used to analyze MT, GCC, and RNFL thickness. To compare the discrimination capabilities between the MT, GCC, and RNFL thickness measurements, we analyzed the areas under the receiver operating characteristic (ROC) curves (AUCs). The relationships between GCC and RNFL measurement and also the relationships of the groups, with age, gender, GCC, and RNFL thickness were assessed.

Results

Normal subjects showed the thickest superior and inferior GCC, followed by in order NTG and POAG (p?<?0.05). While there was a statistically difference in MT value of the normal subjects and the glaucoma patients (p?<?0.05), MT value did not differ between POAG and NTG (p?<?0.05). RNFL thickness parameters were significantly greater in normal subjects, followed in order by the NTG, and POAG (p?<?0.05). Between the normal and entire glaucoma groups, all GCC and RNFL parameters showed the similar discrimination power. RNFL thickness parameters correlated significantly with all GCC thickness (p?<?0.05). Superior RNFL thickness was the only independent variable between the POAG and NTG patients (odds ratio (OR) 0.942, p?=?0.004, 95 %CI 0.905–0.981).

Conclusions

SD-OCT evaluation results suggest higher GCC and RNFL parameters for NTG than POAG.     

Tocilizumab treatment for refractory uveitis-related cystoid macular edema

Background

This retrospective study investigated the efficacy of tocilizumab (TCZ), a fully humanized antibody that binds both to soluble and membrane bound IL-6 receptors, for the treatment of uveitis-related cystoid macular edema (CME) refractory to immunomodulatory therapy.

Methods

Five refractory patients with uveitis-related CME who received TCZ between January and August 2012 were included. All patients received 8 mg/kg TCZ at 4-week intervals. Data regarding patient demographics, use of immunosuppressive drugs, biologic agents or intravitreal therapies prior to TCZ infusions were collected. Main outcome measure was central foveal thickness (CFT) measured by optical coherence tomography at 6 months. Secondary outcome measures were degree of anterior and posterior chamber inflammation (Standardization of Uveitis Nomenclature Working Group criteria) and visual acuity (logarithm of the minimum angle of resolution [log-MAR]) at month 6. Adverse events (AEs) related to TCZ therapy were also assessed.

Results

Eight eyes from five patients (all females) were included. Mean age was 49.4 years (range, 30–68). Mean follow-up was 8.4 months (range, 6–12). Before TCZ, all patients received and failed conventional immunosuppressive therapy and had received at least another biologic agent. Uveitis diagnoses were Birdshot chorioretinopathy (n?=?3), juvenile idiopathic arthritis (JIA)-associated uveitis (n?=?1), and idiopathic panuveitis (n?=?1). Mean evolution of CME was 13.4 years (range, 2–30). Mean baseline CFT (95 % confidence interval) was 602?±?236 μm at baseline, 386?±?113 μm at month 1 (p?=?0.006), 323?±?103 μm at month 3 (p?=?0.026), and 294.5?±?94.5 μm at month 6 (p?=?0.014). Median best-corrected visual acuity (BCVA) improved from 0.66?±?0.57 at baseline to 0.47?±?0.62 at month 6 (p?=?0.035). After 6 months, an improvement of ≥ 2 lines of BCVA was observed in 50 % of eyes (p?=?0.028) remained stable in 25 % and worsened in none of the patients. Sustained uveitis remission was achieved in all patients. No AEs were reported.

Conclusions

These data suggest that TCZ is effective for treating CME in otherwise treatment-refractory cases of uveitis.     

Pain score of patients undergoing single spot, short pulse laser versus conventional laser for diabetic retinopathy

Background

To compare pain score of single spot short duration time (20 milliseconds) panretinal photocoagulation (PRP) with conventional (100 milliseconds) PRP in diabetic retinopathy.

Methods

Sixty-six eyes from 33 patients with symmetrical severe non-proliferative diabetic retinopathy (non-PDR) or proliferative diabetic retinopathy (PDR) were enrolled in this prospective randomized controlled trial. One eye of each patient was randomized to undergo conventional and the other eye to undergo short time PRP. Spot size of 200 μm was used in both laser types, and energy was adjusted to achieve moderate burn on the retina. Patients were asked to mark the level of pain felt during the PRP session for each eye on the visual analog scale (VAS) and were examined at 1 week, and at 1, 2, 4 and 6 months.

Results

Sixteen women and 17 men with mean age 58.9?±?7.8 years were evaluated. The conventional method required a mean power of 273?±?107 mW, whereas the short duration method needed 721?±?406 mW (P?=?0.001). An average of 1,218?±?441 spots were delivered with the conventional method and an average of 2,125?±?503 spots were required with the short duration method (P?=?0.001). Average pain score was 7.5?±?1.14 in conventional group and 1.75?±?0.87 in the short duration group (P?=?0.001). At 1 week, 1 month, and 4 months following PRP, the mean changes of central macular thickness (CMT) from baseline in the conventional group remained 29.2 μm (P?=?0.008), 40.0 μm (P?=?0.001), and 40.2 μm (P?=?0.007) greater than the changes in CMT for short time group.

Conclusion

Patient acceptance of short time single spot PRP was high, and well-tolerated in a single session by all patients. Moreover, this method is significantly less painful than but just as effective as conventional laser during 6 months of follow-up. The CMT change was more following conventional laser than short time laser.     

Evaluation of relationship between retinal nerve fiber layer thickness progression and visual field progression in patients with glaucoma

Purpose

To evaluate the capability of optical coherence tomography (OCT), retinal nerve fiber layer (RNFL) thickness, and visual field (VF) measurements in glaucoma progression detection.

Methods

The study examined 62 eyes of 37 glaucoma patients observed over a 3-year period. All eyes underwent at least four serial RNFL measurements performed by Cirrus OCT, with the first and last measurements separated by at least 3 years. VF testing was performed by using the Swedish interactive threshold algorithm (SITA) Standard 30-2 program of the Humphrey field analyzer (HFA) on the same day as the RNFL imaging. Both serial RNFL thicknesses and VF progression were assessed by the guided progression analysis (GPA) software program. RNFL thickness progression was evaluated by event analysis. Total deviation (TD) in the superior or inferior hemifield was also examined.

Results

A total of 295 OCT scans and 295 VFs were analyzed. Five eyes exhibited progression by OCT only and 8 eyes exhibited progression by VF GPA only. When the analysis was based on the combined measurement findings, progression was noted in 6 eyes. The average of the progressive hemifield TD at baseline for combined RNFL and VF progression was ?3.21 ± 1.38 dB, while it was ?2.17 ± 1.14 dB for RNFL progression and ?9.12 ± 3.75 dB for VF progression. The average of the progressive hemifield TD indicated a significant advancement of VF progression as compared to RNFL progression (P = 0.002).

Conclusions

When a mild VF defect is present, OCT RNFL thickness measurements are important in helping discern glaucoma progression.     

Long-term effects of ranibizumab treatment delay in neovascular age-related macular degeneration

Background

Intravitreal injections of ranibizumab are the standard of care for neovascular age-related macular degeneration (AMD). In clinical trials, comparable efficacy has been shown for either monthly injections or as needed injections upon monthly controls. Unlike in trial settings, treatment in clinical routine is often delayed by complex approval procedures of health insurance and limited short-term surgical capacities.

Methods

Eighty-nine patients with neovascular AMD were followed for 12 months. Early treatment diabetic retinopathy study (ETDRS) visual acuity (VA), Radner reading VA and spectral domain optical coherence tomography were performed monthly, with additional fluorescein angiography if needed. After an initial loading phase of three consecutive monthly intravitreal injections with ranibizumab, re-injections were performed when recurrent activity of choroidal neovascularization (CNV) was detected.

Results

After an initial increase to a value of +5.0?±?11.87 ETDRS letters from baseline, VA constantly decreased over 12 months to a value of ?0.66?±?16.82 ETDRS letters below baseline. Central retinal thickness (CRT) decreased from a value of 438.1?±?191.4 μm at baseline to a value of 289.9?±?138.6 μm after initial therapy and stabilized at a value of 322.4?±?199.5 μm. Loss of VA during latency between indication to treat and treatment was significantly greater than re-gain of VA after re-initiation of therapy (?2.2?±?5.0 versus 0.4?±?7.4 letters; p?=?0.046).

Conclusions

Latency between indication to treat and treatment is responsible for irreversible VA deterioration. A successful PRN treatment regimen for neovascular AMD requires immediate access to therapy after indication.     

Retinal thickness changes following photodynamic therapy in chronic central serous chorioretinopathy

Objective

To evaluate changes in neural retina (NR) thickness and best-corrected visual acuity (BCVA) induced by treatment of chronic central serous chorioretinopathy (CSC) by photodynamic therapy (PDT).

Patients and methods

Retrospective study of 25 eyes of 25 patients with chronic CSC treated by “full-fluence” PDT. LogMAR BCVA and Stratus optical coherence tomography (OCT) were evaluated before treatment and 1?year after PDT. Twenty-four eyes from 24 patients with non-chronic, non-PDT-treated forms of CSC were evaluated as a control group.

Results

NR foveal thickness before PDT was 182?±?43.4?μm (range, 92–246) vs 148.1?±?30.9?μm (range, 101–220) 1?year after treatment (p?=?0.004; Student's t-test paired data). NR foveal thickness in the untreated eyes was 204.6?±?30.7?μ (range, 132–249) vs 192.5?±?26.4?μ (range, 123–235) after self-resolution (p?=?0.03; Student's t-test paired data). Basal NR thickness was statistically significant different between both groups (p?=?0.04; Student's t-test); this difference continued to be significant at the end of the follow-up (p?<?0.01; Student's t-test). All the patients with chronic CSC treated by PDT showed anatomic resolution, and BCVA improved from 0.38?±?0.35 to 0.23?±?0.29 (p?=?0.007; Student's t-test paired data). Final BCVA and basal and final NR thickness showed poor correlation (Pearson?=?0.2 and 0.1 respectively).

Conclusions

The use of PDT in chronic CSC induces NR thickness thinning. This change is not correlated with a decrease in BCVA. Spontaneous resolution of classic CCS also showed significant NR thinning.     

Relationship of change in central corneal thickness to visual field progression in eyes with glaucoma

Background

To assess the relationship between baseline central corneal thickness (CCT) and/or ongoing CCT change over time with subsequent visual field progression.

Methods

One hundred sixty three eyes of 163 patients with medically treated glaucoma were followed up for 6.8?±?1.8 years. Exclusion criteria was laser or intraocular surgery. Baseline and follow up CCT, confocal scanning laser tomography and visual fields were performed. CCT and CCT change related to visual field progression using Glaucoma Progress Analysis were assessed. Multivariate logistic regression analysis for predictive factors of glaucoma progression was used to analyze data.

Results

Thinner baseline CCT was associated with more advanced damage at presentation, mean deviation (MD) (r?=?0.17, p?=?0.02) and neuroretinal rim area (NRR) (r?=?0.20, p?=?0.02). Progressing eyes had significantly thinner (p?=?0.01) baseline CCT compared to non-progressing eyes. The slope of visual field change was significantly greater (p?=?0.05) for thinner (<540 μm) as compared to thicker eyes. A small but significant CCT reduction (12.78?±?13.35 μm, p?<?0.0001) was noted in all eyes; however, there was no significant difference (p?=?0.95) in the amount of change between progressing and non-progressing eyes. CCT change did not correlate with MD or NRR change. A thinner CCT (Odds ratio?=?1.80, p?=?0.02), but not CCT change (Odds ratio?=?1.07, p?=?0.69), was a significant risk factor for glaucoma progression.

Conclusions

CCT correlates significantly with the amount of glaucomatous damage at presentation. Thinner corneas may be associated with increased risk of visual field progression. CCT reduced slightly over time in eyes with glaucoma; but the magnitude of this change was not related to visual field progression.     

Investigation of blood flow regulation and oxygen saturation of the retinal vessels in primary open-angle glaucoma

Purpose

To examine the supply of oxygen to the retina in primary open-angle glaucoma (POAG).

Methods

Forty-one patients with primary open-angle glaucoma (mean age 64.1?±?12.9 years) and 40 healthy subjects (63.6?±?14.1 years) were included. Fundus images, centered at the optic disc, were taken using the Retinal Vessel Analyzer (RVA). The vessel diameters were calculated as central retinal artery (CRAE) and vein equivalent (CRVE) from diameter measurements in the peripapillary vessels. The oxygen saturation of the arteries and veins was investigated employing a two-wavelengths technique. After the measurement at baseline, the vascular response to flicker light exposure was measured.

Results

In glaucoma patients the mean oxygen saturation of the retinal veins at baseline was higher than in the healthy controls (64.36?±?7.11 vs. 59.78?±?8.47, p?=?0.01), whereas the mean arteriovenous oxygen saturation difference was lower (33.07?±?5.24 vs. 37.53?±?6.95, p?=?0.002). The arterial oxygen saturation as well as the arterial and venous diameters showed no difference between the groups. The increase of the CRVE during flicker light stimulation (3.72?±?3.29 % vs. 5.43?±?4.04, p?=?0.039), as well as the change of the venous oxygen saturation (2.08?±?3.74 % vs. 4.18?±?3.88 %, p?=?0.016) and the arteriovenous saturation difference (?2.1?±?3.31 % vs. ?4.43?±?3.6 %, p?=?0.003) were smaller in POAG patients than in the healthy group.

Conclusions

The reduction in the arteriovenous difference in oxygen saturation in POAG patients might show a decreased oxygen demand of the retina caused by the glaucomatous loss of neuroretinal tissue. The lower extent of the flicker light-induced change of the diameter of retinal veins and the venous oxygen saturation could indicate an impairment of blood flow regulation.