Unilateral Acute Primary Angle Closure Research Articles

Acute primary angle closure concurrent with coronavirus disease 2019 recurrence in Northern China: A retrospective multi-centre study

Aims and objectivesDuring the new coronavirus disease 2019 (COVID-19) outbreak period, there was increasing presentation in the number of patients with acute primary angle closure (APAC). This study aimed to report the occurrence of APAC during the COVID-19 post-restriction period and investigate the related characteristics of these patients with APAC. MethodsThis retrospective, multi-center study included consecutive patients seeking APAC treatment at two eye centers in China from December 7, 2022 to January 13, 2023 (post-restriction period) and from December 7, 2021 to January 13, 2022 (control period). Electronic medical records were reviewed, and ocular data of the affected eye(s) were analyzed for patients with unilateral or bilateral APAC. Information including COVID-19 related symptoms, medications used for COVID-19 infection, and living habits and emotions related to the COVID-19 outbreak during the post restriction period were collected using a questionnaire. ResultsOverall, 189 (219 APAC eyes) and 51 (54 APAC eyes) patients with APAC were identified during the post-restriction and control periods, respectively. The patients identified during the post-restriction period were younger (P = 0.043) and had a longer duration from symptoms to treatment (P = 0.039), shorter axial length (P = 0.002), larger pupil diameter (P = 0.004), larger vertical cup disc ratio (P = 0.004), poorer mean deviation values (P = 0.003), and more glaucomatous optic neuropathy diagnoses (P = 0.032) compared with the patients with APAC identified during the control period. Among 151 included patients with APAC who completed the questionnaires, 130 patients with APAC were diagnosed with concurrent COVID-19 infection, of which 54 (41.5 %) had coughing and/or vomiting as the main symptoms. Of these, 89.2 % spent 0 h per day on outdoor activity; 44.6 % drank more water than usual, with 14.6 % drinking more than twice the amount of water than usual; 91.5 % used antipyretics; and 20.0 % had mood swings, including anxiety, depression, and tension, during the concurrent COVID-19 infection. ConclusionIn our study, a significant increase in the number of patients presenting with APAC with certain characteristics was observed during the COVID-19 post-restriction period. And whether COVID-19 symptoms, such as coughing and vomiting, and behavioral and psychological changes caused by COVID-19 infection contributing to the concurrence of APAC and COVID-19 recurrence require further investigation.

SD-OCT assessment and visual field changes 1 year or more after a single episode of unilateral acute primary angle closure

Objective: To evaluate structural and visual field (VF) changes after ≥1 year of a single acute primary angle closure (APAC) attack using spectral-domain optical coherence tomography (SD-OCT) and standard automated perimetry (SAP). Methods: Patients with a single unilateral APAC crisis at least 1 year ago were included consecutively from 2013 to 2016. Contralateral eye was used as control. All patients underwent ophthalmic examination, RNFL imaging by SD-OCT, and SAP using Octopus 1-2-3. Results: 54 eyes (27 patients) were enrolled. [...]

Comparison of iridolenticular contact area under different light brightness between post primary acute angle closure and cataract eyes

BackgroundTo study the iridolenticular contact area (ILCA) under different light conditions in acute primary angle closure (APAC).MethodsThis cross-sectional, observational study involved 22 unilateral APAC patients and 59 cataract patients (59 eyes). Images of the APAC eyes, fellow eyes and cataract eyes were collected by anterior segment optical coherence tomography (ASOCT) under different light conditions respectively. The ILCA, anterior chamber width (ACW), anterior chamber area (ACA), lens vault (LV), angle opening distance at 750 μm (AOD750), trabecular iris space area at 750 μm (TISA750) and iris area at 750 μm (IA750) were measured using Image J software.ResultsThe ILCA of cataract eyes were significantly larger than APAC eyes (4.424 ± 1.208 vs 4.049 ± 2.725mm2, P = 0.034) and fellow eyes (4.424 ± 1.208 vs 3.651 ± 1.629 mm2, P = 0.008) under dark condition. Under dark condition, ILCA of APAC eyes was negatively correlated with AOD750 (r = -0.444, P = 0.038), TISA750 (r = -0.498, P = 0.018). The ILCA of cataract eyes under dark condition was significantly greater than under bright condition (4.424 ± 1.208 vs 2.526 ± 0.992 mm2, P < 0.001).ConclusionsThis study showed that ILCA in both APAC eye and fellow eye were smaller than cataract eye. Future study should focus on both the contact area and force at the interface of lens and iris with larger sample size.

Optical coherence tomography angiography of the macular microcirculation in acute primary angle closure treated with phacoemulsification.

To measure the changes of macular microcirculation in cases with unilateral acute primary angle closure (APAC) who were managed by phacoemulsification. Patients with unilateral APAC and managed by phacoemulsification were enrolled. The contralateral unaffected eyes were served as fellow group, and normal individuals were recruited as control group. Optical coherence tomography angiography (OCT-A) was performed to analyze the macular whole image vessel density (wiVD) and parafoveal vessel density (pfVD). The retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thicknesses were assessed using spectral-domain optical coherence tomography. A total of 36 APAC patients and 35 eyes from 35 normal individuals were recruited. In the APAC eyes, the mean wiVD (42.1% ± 3.7%) and pfVD (45.2% ± 3.8%) in the superficial layers (wiVD-SL and pfVD-SL) were both significantly reduced, compared to fellow eyes (45.7% ± 3.1%, 48.7% ± 3.1%) and control eyes (44.4% ± 4.7%, 47.4% ± 5.1%) (P < 0.05). They were all statistically correlated with RNFL, GCC, visual field pattern standard deviation (PSD), and mean deviation (MD). The macular OCT-A parameters including wiVD-SL and pfVD-SL were significantly reduced in the eyes with APAC compared to the fellow unaffected eyes and normal control eyes. They were correlated well with RNFL, GCC, PSD and MD. The macular vessel density parameters may help monitor the progression of APAC.

Changes in Optic Nerve Head Vessel Density After Acute Primary Angle Closure Episode.

To evaluate the changes in circumpapillary vessel density (cpVD) and retinal nerve fiber layer (RNFL) thickness after an acute primary angle closure (APAC) episode. Twenty-eight patients (28 pair of eyes) with unilateral APAC and 39 normal subjects (64 eyes) were included in this prospective, observational study. cpVD as measured by optical coherence tomography angiography and RNFL thickness as measured by spectral-domain optical coherence tomography were compared at 6 weeks after an APAC episode between affected, unaffected, and normal eyes. cpVD and RNFL thickness at 1 week and 6 weeks after APAC were also compared in APAC eyes in qualified images. At 6 weeks, cpVD was significantly lower in APAC eyes (57.3% ± 6.8%), compared to fellow eyes (63.1% ± 3.5%) and control eyes (63.6% ± 3.4%) (P < 0.001). There was diffuse microvascular dropout with greater vessel density loss in the superonasal sector. APAC eyes had thinner RNFL globally and in each sector (except temporal and nasal sectors) than in fellow and normal eyes at 6 weeks. cpVD in the affected eyes was significantly greater at 1 week (56.3% ± 5.3%) than values at 6 weeks (53.5% ± 7%) (P = 0.003) but less than cpVD in the fellow eyes (62.4% ± 5.0%) (P < 0.001). RNFL thickness for the APAC eyes at 1 week (120.6 ± 18.0 μm) was greater than the analogous values for affected eyes (90.1 ± 13.2 μm; P = 0.037) and fellow eyes at 6 weeks (102.5 ± 5.7 μm; P = 0.001). Vessel density decreased over 6 weeks after an APAC episode compared with the contralateral unaffected eyes. In contrast, there was an initial increase in RNFL thickness that was followed by a subsequent decrease.

Peripapillary retinal vessel density in eyes with acute primary angle closure: an optical coherence tomography angiography study.

The purpose was to investigate peripapillary retinal vessel density in resolved acute primary angle closure (APAC) eyes. This was a prospective, cross-sectional observational study. Thirty-four eyes of 34 patients with unilateral APAC were included, together with the fellow eyes with primary angle closure suspect (PACS) as controls. Peripapillary retinal vessel density was measured using optical coherence tomography (OCT) angiography. Peripapillary retinal vessel density was compared in both eyes and the potential relationship with visual field (VF) test results was evaluated. After an acute attack, the peripapillary retinal vessel density was lower in the APAC than in the PACS eyes (79.3 ± 8.2 versus 85.6 ± 4.9, respectively; P = 0.001). The VF mean deviation (MD) (-7.7 ± 6.7 versus -3.3 ± 1.8dB, P = 0.002), and the pattern standard deviation (PSD) (4.6 ± 3.3 versus 2.4 ± 0.9dB, P = 0.001) were worse for the APAC than the PACS eyes, but both had similar thicknesses of the retinal nerve fiber layer (RNFL) (111.8 ± 9.6 versus 114.1 ± 29.1μm, P = 0.880) and ganglion cell complex (GCC) (94.7 ± 7.5 versus 91.8 ± 9.3μm, P = 0.328). The peripapillary retinal vessel density was significantly correlated with the VF MD (vessel density: r = 0.455, P = 0.008) and PSD (vessel density: r = -0.592, P < 0.001) in the APAC eyes. Even when IOP was normalized after the acute attack, the APAC eyes had a lower peripapillary retinal vessel density, which was correlated with the VF values. OCT angiography is a reliable method for detecting vascular changes in glaucomatous eyes that show no thinning of the RNFL and GCC.

Factors Associated with the Retinal Nerve Fiber Layer Loss after Acute Primary Angle Closure: A Prospective EDI-OCT Study.

PurposeTo determine the factors associated with retinal nerve fiber layer (RNFL) loss in eyes with acute primary angle-closure (APAC), particularly focusing on the influence of the change in the anterior lamina cribrosa surface depth (LCD).MethodsAfter the initial presentation, 30 eyes with unilateral APAC were followed up at the following specific time points over a 12-month period: 1 week, 1~2 months, 2~3 months, 5~6 months, and 11~12 months. These follow-ups involved intraocular pressure measurements, enhanced depth-imaging spectral-domain optical coherence tomography (SD-OCT) scanning of the optic disc, and measurements of the circumpapillary RNFL thickness. The prelaminar tissue thickness (PLT) and LCD were determined in the SD-OCT images obtained at each follow-up visit.ResultsRepeated measures analysis of variance revealed a significant pattern of decrease in the global RNFL thickness, PLT, and LCD (all p<0.001). The global RNFL thickness decreased continuously throughout the follow-up period, while the PLT decreased until 5~6 months and did not change thereafter. The LCD reduced until 2~3 months and then also remained steady. Multivariable regression analysis revealed that symptoms with a longer duration before receiving laser peripheral iridotomy (LI) (p = 0.049) and a larger LCD reduction (p = 0.034) were significant factors associated with the conversion to an abnormal RNFL thickness defined using OCT normative data.ConclusionEarly short-term decreases in the PLT and LCD and overall long-term decrease in the peripapillary RNFL were observed during a 12-month follow-up after an APAC episode. A longer duration of symptoms before receiving LI treatment and larger LCD reduction during follow-up were associated with the progressive RNFL loss. The LCD reduction may indicate a prior presence of significant pressure-induced stress that had been imposed on the optic nerve head at the time of APAC episode. Glaucomatous progression should be suspected in eyes showing LCD reduction after the APAC remission.

Anterior segment morphology after acute primary angle closure treatment: a randomised study comparing iridoplasty and medical therapy

PurposeTo compare the effect of argon laser peripheral iridoplasty (ALPI) and conventional medical therapy in the immediate treatment of acute primary angle closure (APAC) using anterior segment optical coherence tomography...

Diurnal intraocular pressure changes in eyes affected with acute primary angle closure and fellow eyes after laser peripheral iridotomy.

To evaluate diurnal curves of intraocular pressure (IOP) in eyes affected with unilateral acute primary angle closure (APAC) after laser peripheral iridotomy (LPI), and fellow eyes. The medical records of 22 female patients (44 eyes) with unilateral APAC and LPI performed OU were reviewed along with those of 48 normal control subjects (48 eyes). None of the subjects used glaucoma medications after LPI. IOP was measured with a Goldman applanation tonometer during waking hours and in a sitting position every 2 h between 09:00 and 23:00. IOP profiles were compared including the means, peaks, trough IOPs, and IOP fluctuations of the affected, fellow, and normal eyes. The IOPs of the affected eyes were significantly higher than those of normal eyes at every time point measured, including peak and trough IOPs. The diurnal IOPs of fellow eyes were higher than those of normal eyes, though not significantly. There were no significant differences in IOP fluctuation between the affected, fellow, and normal eyes. IOP diurnal curves for APAC affected, fellow, and normal eyes were not statistically different (repeated measures ANOVA, p = 0.865). The mean coefficient of IOP in affected and fellow eyes ranged from 0.486 to 0.604. There were no clinically significant differences among the three groups in terms of IOP diurnal curves, and thus LPI did not have a significant effect on diurnal patterns of IOP. Though the diurnal IOPs of affected eyes after LPI was significantly higher than those of normal eyes, the IOP range was not acute.

Choroidal Thickness Decreased in Acute Primary Angle Closure Attacks with Elevated Intraocular Pressure

Purpose: To study the choroidal thickness (CT) changes in patients having unilateral acute primary angle closure (APAC) attacks with elevated intraocular pressure (IOP).Methods: This study included 23 patients with unilateral APAC attacked eyes. The CT at macular and peripapillary regions were measured in both eyes of the subjects using enhanced depth imaging-optical coherence tomography (EDI-OCT). We compared the CT difference between the two eyes in the same patients.Results: The average IOP of the attacked eyes was 39.4 ± 11.7 mmHg, significantly higher than the fellow eyes with IOP of 13.3 ± 3.8 mmHg (p < 0.001). Significant difference (p < 0.001) was also found in average subfoveal choroidal thickness (SFCT) of the attacked eyes (208.5 ± 80.6 μm) and the fellow eyes (258.4 ± 83.8 μm). In addition, the CT of the attacked eyes at all locations along the horizontal and vertical sections across the macular fovea was significantly smaller compared with the fellow eyes (p < 0.05). At the peripapillary region, the CT of the temporal, superotemporal and inferotemporal segments to the optic disk was significantly thinner than that in the fellow eyes (p < 0.05).Conclusions: The CT of the APAC attacked eyes with extensive high IOP was significantly thinner than that of the fellow eyes with normal IOP. The changes have possibly resulted from the shrinkage of the blood vessel within the choroid and will lead to the ischemia of the retina.

Does Acute Primary Angle-Closure Cause an Increased Choroidal Thickness?

We compared the choroidal thickness of the eyes of patients with acute primary angle-closure (APAC) with fellow eyes in the same patients. The analysis included 21 participants with unilateral APAC affected eyes and 21 fellow eyes with a diagnosis of primary angle-closure suspect (PACS). Enhanced depth imaging-optical coherence tomography (EDI-OCT) was used to measure the macular and peripapillary retinal and choroidal thickness in both eyes. The average choroidal thickness of the APAC eyes at each location or segment was compared to that of the fellow eyes. At all macular locations, the choroidal thickness was greatest at the subfovea for both groups. Comparison of the choroidal thickness between the groups showed that the thickness in the APAC eyes was significantly greater than in the PACS eyes at all locations except at 1 mm, 3 mm superior, 3 mm inferior, and 3 mm temporal from the fovea (P < 0.005). The mean subfoveal choroidal thickness was 349.0 ± 78.1 μm in the APAC eyes and 308.1 ± 70.5 μm in the PACS eyes, with a statistically significant difference (P < 0.005). Multivariable linear regression analysis showed that the subfoveal choroidal thickness was significantly greater in association with the APAC diagnosis and diastolic blood pressure and thinner in association with older subjects. APAC eyes have a higher level of macular choroidal thickness than PACS eyes when the IOP is reduced. However, the source of this difference is unclear and must be investigated further.

Quantification of Retinal Nerve Fiber Layer Thickness After Unilateral Acute Primary Angle Closure in Asian Indian Eyes

To determine retinal nerve fiber layer thickness (RNFLT) using Spectral optical coherence tomography/scanning laser ophthalmoscope (Spectral OCT/SLO) in Asian Indian eyes after single, unilateral attack of acute primary angle closure (APAC). Thirty-two patients with unilateral attack of APAC with normal optic disc and normal visual field, unaffected fellow eyes, and 35 age-matched normal control eyes were enrolled for the study. Six weeks after the remission of acute attack, peripapillary average, quadrant, and clock-hour RNFLT were compared between 3 groups using Spectral OCT/SLO. APAC patients had mean IOP of 51.3±13.3 mm Hg (range, 40-74) at the time of presentation with acute attack in the affected eye and 14.9±2.9 mm Hg at 6 weeks after resolution of APAC. Duration of symptoms of acute attack was 35.9±23.8 hours. Significant differences were found between RNFLT in APAC and fellow eyes for most the parameters except for 1, 4, 6, and 7-o'clock-hour sector. Most of the RNFLT parameters showed statistically significant difference between APAC and normal control eyes except for temporal quadrant, 6, 7-o'clock-hour sectors. Statistically significant differences were found between RNFLT in unaffected fellow and normal control eyes for most of the parameters except for 6, 7, 11 o'clock-hour sectors. RNFLT was found to be significantly thinner in APAC and unaffected fellow eyes when compared with normal age-matched controls. Hence, patients with APAC should be monitored carefully to determine its long-term effects on optic disc, RNFLT, and visual fields. Longitudinal studies can determine whether the RNFLT measurements remained stable or showed progression in these patients.

Changes in retinal nerve fibre layer, optic nerve head morphology, and visual field after acute primary angle closure

To determine and correlate the long-term changes in retinal nerve fibre layer (RNFL) thickness, optic nerve head (ONH) morphology, and visual fields after a single episode of acute primary angle closure (APAC). This was a cross-sectional comparative study of patients at National University Hospital (Singapore) from 2000 to 2006 after an episode of unilateral APAC. The peripapillary and macular RNFL were measured using Stratus optical coherence tomography (OCT) and ONH configuration was assessed using Heidelberg Retina Tomography (HRT)-III. Humphrey perimetry was also performed, and the presence of disc pallor was noted. APAC eyes were compared with fellow eyes as matched controls. Twenty-five patients were assessed at a median of 33 months (range, 11-85 months) after APAC. OCT showed that there was a reduction in the peripapillary and outer macular RNFL thickness in APAC eyes compared with controls. Humphrey perimetry revealed significantly reduced mean deviation (P=0.006) and increased pattern standard deviation (P=0.045) in APAC eyes compared with controls. HRT-III showed no difference in mean rim area, rim volume, or cup-disc ratio between APAC eyes and controls. Disc pallor was present in nine APAC eyes (36%) but was absent in fellow eyes (P=0.002), and was associated with peripapillary RNFL thinning, visual field loss, and an increased interval between the onset of symptoms and normalization of intraocular pressure (P=0.023). APAC results in peripapillary and outer macular RNFL loss, visual field defects, and optic disc pallor, even in cases in which the ONH configuration remains unchanged.

New comparative ultrasound biomicroscopic findings between fellow eyes of acute angle closure and glaucomatous eyes with narrow angle

To compare morphometric features between fellow acute primary angle-closure (APAC) eyes and glaucomatous or suspect eyes with narrow angle (NA). Fellow eyes of 30 patients with unilateral APAC and 30 with NA were evaluated by ultrasound biomicroscopy (UBM) under light and dark conditions. UBM parameters such as anterior chamber depth (ACD), angle opening distance at 250 microm/500 microm from the scleral spur (AOD250/AOD500), trabecular ciliary process distance (TCPD) and iris-lens contact distance (ILCD) were measured in the superior (SQ) and inferior (IQ) quadrants. Significant differences between APAC fellow and NA eyes were found in ACD, P<0.001; AOD250 at SQ and IQ, P<0.001; AOD500 at SQ and IQ, P<0.001; TCPD light, P=0.010 and TCPD dark at SQ, P=0.031; and TCPD light at IQ, P=0.010. Significant differences between light and dark examinations of APAC fellow eyes were found in ILCD (P=0.009) at SQ and ILCD at IQ (P=0.006), and of NA eyes in ILCD at SQ (P=0.047) and ILCD at IQ (P<0.001). APAC fellow eyes have a more crowded anterior segment and shallower ACD than NA eyes. ILCD decreases in both groups when the illumination conditions change from light to dark.

Longitudinal Changes in Retinal Nerve Fiber Layer Thickness after Acute Primary Angle Closure Measured with Optical Coherence Tomography

Longitudinal follow-up of peripapillary retinal nerve fiber layer (RNFL) thickness after an episode of acute primary angle closure (APAC) using Stratus optical coherence tomography (OCT). Seventeen patients who had experienced a single unilateral APAC episode (intraocular pressure, >50 mm Hg) were enrolled. The average and superior, temporal, inferior, and nasal quadrant RNFL thicknesses of the affected and fellow eyes at 1, 4, and 12 weeks after remission were compared by using StratusOCT. The relationship between average RNFL thickness and interval of follow-up were evaluated with regression analysis. The mean duration of the APAC episode was 13.8 hours (range, 3-40). Comparison of the average and four quadrant RNFL thicknesses in the affected eyes longitudinally showed significant differences between 1 and 4, and 1 and 12 weeks, but not between 4 and 12 weeks. The average and four-quadrant RNFL thicknesses for the affected eyes were greater than the analogous values for fellow eyes at 1 week. In contrast, the inferior- and superior-quadrant RNFL thicknesses for the affected eyes were lower at 4 and 12 weeks, whereas the average and nasal quadrant values for the affected eyes were lower than those in fellow eyes at 12 weeks. Average RNFL thickness for the affected eyes was correlated with the interval of follow-up by using inverse regression analysis (P < 0.001; R(2) = 0.60). Controlling for duration of APAC episode, the interval of follow-up on RNFL thickness reduction remained significant (P < 0.001, r = -0.69). This study demonstrated an initial increase in diffuse RNFL thickness after a single APAC episode, followed by a subsequent decrease.

Changes in the Optic Disc after Acute Primary Angle Closure

To evaluate the changes in optic disc morphology in the first 4 months after an episode of acute primary angle closure (APAC) using stereoscopic optic disc photography and computer-assisted planimetry. Prospective observational case series. Forty-seven Asian subjects with unilateral APAC who were successfully treated with laser peripheral iridotomy (LPI). Cup-to-disc ratio (CDR) and optic cup and neuroretinal rim areas. Stereoscopic optic disc photographs were taken 2 and 16 weeks after LPI, and the images were analyzed by computer-assisted planimetry. The overall, quadrantic, and 30 degrees sector areas of the optic disc, CDR, and neuroretinal rim area were analyzed by 2 independent masked graders, and the mean of the readings was used to calculate changes in optic disc parameters. The majority of the subjects were female (66%) and Chinese (90%), and the mean age was 67.6+/-11.2 years (range, 40-94). In APAC eyes from week 2 to week 16, the mean CDR increased from 0.56+/-0.05 to 0.59+/-0.03 (P<0.001), and the mean neuroretinal rim area decreased from 1.74+/-0.31 mm2 to 1.59+/-0.27 mm2 (P<0.001). Quadrantic and sector analysis showed preferential loss of neuroretinal rim area at the superotemporal and inferotemporal areas. There was no significant change in optic disc parameters in the fellow eyes over the study period. This study demonstrated changes in optic disc morphology from week 2 to week 16 after an episode of APAC. The pattern of optic nerve damage demonstrated in our study was comparable with that seen in primary open-angle glaucoma and experimental glaucoma models.

Lens Opacity, Thickness, and Position in Subjects With Acute Primary Angle Closure

To compare lens thickness (LT), lens position (LP), relative lens position (RLP), and degree and type of lens opacity between affected and fellow eyes of subjects with acute primary angle closure (APAC) to identify any differences in lens characteristics that may be contributory to the acute episode. In addition, axial length (AL) and anterior chamber depth (ACD) measurements were evaluated. Seventy-three study subjects with unilateral APAC were treated with sequential laser iridotomy (LI) in both eyes. Two weeks after LI, ACD, LT, and AL measurements were made in both eyes using ultrasound pachymetry. LP was defined as ACD+1/2LT and RLP as LP/AL. The Lens Opacity Classification III (LOCS III) System was used for grading lens opacity. The subjects were 90% Chinese and 63% female. Mean age was 61.0+/-10.9 years. Significant differences between the affected and fellow eyes were found in the ACD (2.11+/-0.35 vs 2.18+/-0.23; P=0.02) and LP (4.61+/-0.47 vs 4.75+/-0.29; P=0.02). Cortical opacity was greater in fellow eyes (0.32+/-0.72 vs 0.53+/-0.95; P=0.02). There was no difference in LT, RLP, or degree of lens opacity in the nuclear and posterior subcapsular regions. Compared with fellow eyes, APAC-affected eyes have shallower ACD, more anterior LP, and less cortical opacity. These differences may be contributory to APAC.

Optical Coherence Tomography Measurement of Retinal Nerve Fiber Layer After Acute Primary Angle Closure With Normal Visual Field

To detect retinal nerve fiber layer (RNFL) thickness after a single acute primary angle closure (APAC) attack with normal visual field. Prospective, observational case study. Twenty-eight patients who had a single unilateral APAC attack associated with normal visual fields at three months after remission and 28 single eyes from normal controls were enrolled. Duration of APAC attack was 5.9 +/- 2.7 hours. Comparisons of average RNFL thickness and RNFL thickness in four quadrants and in 12-o'clock-hour segments of the attacked eyes, unaffected fellow eyes, and normal controls were made using fast RNFL thickness (3.4) of Stratus optical coherence tomography. Significant differences were demonstrated comparing the inferior-quadrant RNFL thicknesses for the attacked eyes with those of the normal controls (P = .02) and fellow eyes (P = .02) using one-way analysis of variance with Tukey's tests. Inferior region RNFL thickness was significantly decreased in the attacked eyes after an APAC episode associated with normal visual field.

Cataract Progression after Prophylactic Laser Peripheral Iridotomy: Potential Implications for the Prevention of Glaucoma Blindness

To evaluate changes in lens opacity in the first year after prophylactic laser peripheral iridotomy (LPI) performed in fellow eyes of subjects with acute primary angle closure (APAC). Prospective observational case series. Sixty Asian subjects with unilateral APAC. All fellow eyes underwent prophylactic LPI within the first week of presentation, followed by 1 week of topical steroids. The degree of lens opacity was graded at the slit-lamp examination using the Lens Opacity Classification System III (LOCS III) with standard color photographs as the reference for grading of lens opacity. This was performed 2 weeks, 4 months, and 12 months after LPI. Progression in lens opacity was defined as an increase in LOCS III grade by 2 or more units in any lens region. Lens Opacity Classification Sytem III grades in nuclear, cortical, and posterior subcapsular (PSC) regions. Most patients were Chinese (85%) and female (63.3%), with an average age of 61.5 +/- 10.6 years. The mean baseline LOCS grades in the nuclear, cortical, and PSC regions were 3.58 +/- 0.74, 0.57 +/- 1.08, and 0.23 +/- 0.72, respectively. With 12 months of follow-up, 14 of the 60 eyes (23.3%; 95% confidence interval, 16.9-29.7%) showed significant progression in any lens region. Progression in the nuclear, cortical, and PSC regions was documented in 5%, 6.7%, and 16.7% of cases, respectively. By use of logistic regression, the following factors were not found to be significant for cataract progression in any lens region: age, race, gender, history of hypertension or diabetes, presence of peripheral anterior synechiae or angle width at baseline, and total laser energy delivered. In fellow eyes of APAC, prophylactic LPI is complicated by significant cataract progression, mainly in the posterior subcapsular region. These findings may have implications for the role of prophylactic LPI in the prevention of angle-closure blindness.