Effects of short term increase of intraocular pressure on optic disc cupping

AIMS—To evaluate the effect of acute elevation of intraocular pressure (IOP) on optic disc cupping.
METHODS—10 emmetropic and 10 myopic volunteers were included in this study. The cup area (CA) and cup volume (CV) of the optic disc were determined with the Heidelberg retina tomograph (HRT). After baseline determinations, a suction cup was used to increase the intraocular pressure (IOP) to 20-25 mm Hg above the baseline and HRT images were obtained.
RESULTS—Baseline IOP was 13.5 (SD 1.3) mm Hg and 12.6 (2.6) mm Hg in the emmetropic and myopic groups, respectively. The IOP was elevated to 35.4 (3.3) mm Hg and 34.4 (2.5) mm Hg in the emmetropic and myopic groups, respectively. When compared with their baseline values, the cupping variables (CA and CV) were significantly increased (p<0.05) during the suction treatment in both emmetropic and myopic subjects.
CONCLUSION—There was a significant enlargement in the optic disc cupping during the artificial increment of intraocular pressure in both emmetropic and myopic eyes. In non-glaucomatous eyes the optic nerve head has a partially dynamic topography dependent upon the level of IOP.

Keywords: optic disc; intraocular pressure; compliance; glaucoma     

Prognostic factors affecting the surgical success of gonioscopy-assisted transluminal trabeculotomy

Purpose:To investigate the prognostic factors affecting gonioscopy-assisted transluminal trabeculotomy (GATT) surgical success.Methods:Fifty-three eyes were retrospectively enrolled. Open-angle glaucoma patients with at least 6-month follow-up were included. At baseline, demographic characteristics, intraocular pressure (IOP), number of anti-glaucomatous medications (AG), and glaucoma type were recorded. Postoperatively, IOP, complications, and number of AG were noted. The effects of these parameters on surgical success were investigated.Results:The median follow-up time was 13.7 months. The mean IOP decreased from 25.6 ± 6.2 mm Hg at baseline to 14.6 ± 3.5 mm Hg at final, and the number of AG decreased from 3.2 ± 0.78 to 1.2 ± 1.3. When target IOP was considered as 18 mm Hg and 15 mm Hg, surgical success rates were 81.1% and 60.4%, respectively. When target IOP was considered as 18 mm Hg, a positive effect of the combination with cataract surgery and a negative effect of postoperative macrohyphema on success rates were observed. Other factors did not show any association with the success rates for both target IOP values when analyzed by the Cox proportional hazards regression analysis.Conclusion:Postoperative macrohyphema may affect surgical success rates negatively. The contribution of the combination with cataract surgery is controversial. Glaucoma stage does not seem to affect surgical success.     

Outcomes and risk factors for failure of trabeculectomy with mitomycin C in children with traumatic glaucoma - A retrospective study

Purpose:To determine surgical outcomes and risk factors for failure of trabeculectomy with mitomycin C (TMMC) in pediatric traumatic glaucoma.Methods:Children who underwent TMMC post trauma from January 2014 to December 2019 were reviewed. Demographic features, ocular findings, and surgery details were noted. Surgical success was defined as achieving intraocular pressure (IOP) within 6–21 mm Hg.Results:Seventy-one eyes of seventy patients underwent TMMC. The mean age of the patients was 11.28 ± 3.63 years with a male/female ratio of 13:1. The median time from trauma to IOP rise was 13 days. The majority of the patients (n = 64, 90.1%) had close globe injury. Baseline IOP was 39.3 ± 10.5 mm Hg. Results of the surgery were noted at the last visit. Cumulative success was noted in 51 (71.8%) eyes, while 20 (28.2%) eyes were labeled failures. Mean IOP reduced from 39.3 ± 10.5 to 14.5 ± 8.1 mm Hg. Mean visual acuity improved from 2.3 ± 0.93 to 1.19 ± 1.08 logMAR. Post surgery, the mean follow-up of the patients was 20.3 ± 11.4 months. Age <6 years (RR 3.6), elevated IOP at 1 month after TMMC (RR 2.19), and hypotony within a week of surgery (RR 1.81) were found as independent risk factors of surgical failure.Conclusion:TMMC is effective in reducing IOP in traumatic glaucoma. Young age and inability to control IOP within normal ranges in the immediate period after surgery are important risk factors of failure.     

Scleral Cross-Linking in Form-Deprivation Myopic Guinea Pig Eyes Leads to Glaucomatous Changes

PurposeTo investigate the potential glaucomatous changes caused by scleral cross-linking (CXL) in a guinea pig form-deprivation (FD) myopia model.MethodsEighty 4-week-old tricolor guinea pigs were divided into four groups: FD only, genipin CXL only, FD plus CXL, and control. Refractive error, axial length (AL), intraocular pressure (IOP), and structural and vasculature optic disc changes in optical coherence tomography (OCT) and OCT angiography (OCTA) were measured at baseline and day 21. CXL efficacy was evaluated by scleral rigidity Young''s modulus values. Histological and molecular changes in the anterior chamber angle, retina, and sclera were assessed.ResultsBaseline parameters were similar among groups (P > 0.05). The FD plus CXL group at day 21 had the least increase of AL (0.14 ± 0.08 mm) and highest IOP elevation (31.5 ± 3.6 mmHg) compared with the FD-only group (AL: 0.68 ± 0.17 mm; IOP: 22.2 ± 2.6 mmHg) and the control group (AL: 0.24 ± 0.09 mm; IOP: 17.4 ± 1.8 mmHg) (all P < 0.001). OCT and OCTA parameters of the optic disc in the FD plus CXL group at day 21 showed glaucomatous changes and decreased blood flow signals. Sclera rigidity increased in the CXL and FD plus CXL groups. Advanced glycation end products deposited extensively in the retina, choroid, and sclera of FD plus CXL eyes.ConclusionsCXL causes increased IOP and subsequent optic disc, anterior segment, and scleral changes while inhibiting myopic progression and axial elongation in FD guinea pig eyes. Therefore, applying CXL to control myopia raises safety concerns.     

A pharmacoeconomic analysis to determine the relative cost-effectiveness of bimatoprost 0.03% eye drops and brimonidine 0.2% eye drops in patients of primary open-angle glaucoma/ocular hypertension

Aims:The aim was to compare efficacy and cost-effectiveness of bimatoprost 0.03% and brimonidine 0.2% in primary open-angle glaucoma (POAG)/ocular hypertension (OHT).Statistics:Independent samples t-test was used to compare the efficacy of both drugs.Results:IOP lowering with bimatoprost (8.9 ± 1.598 mm Hg) was significantly (P < 0.0001) higher than brimonidine (6.55 ± 1.26 mm Hg). The number of drops/ml were 33.43 ± 0.52 and 25.49 ± 0.26, respectively, for bimatoprost and brimonidine. Treatment with bimatoprost was costlier than brimonidine with daily costs/eye Rs. 4.02 ± 0.06 and 3.14 ± 0.03, yearly costs/eye Rs. 1467.46 ± 20.74 and 1147.75 ± 11.15, respectively. Bimatoprost was more cost-effective than brimonidine with the cost-effectiveness ratio (CER) respectively Rs. 13.10 ± 2.61/mm Hg and Rs. 13.96 ± 2.86/mm Hg. Incremental CER Rs. 10.43/mm Hg implies lower costs/mm Hg extra IOP lowering by bimatoprost than Rs. 13.96 for brimonidine.Conclusion:In spite of being costlier, bimatoprost is more efficacious and cost-effective than brimonidine.     

Morphologic Changes in the Lamina Cribrosa Upon Intraocular Pressure Lowering in Patients With Normal Tension Glaucoma

PurposeThe purpose of this study was to investigate whether the lamina cribrosa (LC) curve changes in response to intraocular pressure (IOP) reduction following administration of topical ocular hypotensive eye drops in eyes with normal tension glaucoma (NTG).MethodsNinety-three eyes of 93 patients with treatment naïve NTG at initial examination and with ≥20% reduction from baseline IOP following administration of topical ocular hypotensive eye drops were included. Serial horizontal B-scan images of the optic nerve head (ONH) were obtained from each eye using enhanced depth imaging spectral domain optical coherence tomography (OCT) before and 1 year after IOP-lowering treatment. The LC curvature in each eye was assessed by measuring the LC curvature index (LCCI) in horizontal OCT B-scan images obtained at three (superior, central, and inferior) locations spaced equidistantly across the vertical optic disc diameter before and after IOP-lowering treatment. We evaluated the OCT detectible change in the LC curvature based on the interval change of LCCI to exceed the intersession standard deviation of 1.96 times and factors associated with the magnitude of the LCCI change in the eyes showing significant LC change.ResultsIOP decreased from 15.7 ± 2.5 mm Hg at baseline to 11.2 ± 1.7 mm Hg after topical glaucoma medication. Among the 93 subjects, 62 (66.7%) eyes showed the significant reduction of the LCCI (interssetional change over 1.5) after the treatment; greater interssessional change of the LCCI after IOP reduction was associated with younger age (P = 0.020) and larger baseline LCCI (P < 0.001).ConclusionsThe OCT detectible changes in LC curvature occurred in response to a modest decrease in the IOP in the naïve NTG eyes. The therapeutic benefit of these changes need to be assessed in longitudinal studies.     

Posture-Related Changes of Intraocular Pressure in Patients With Acute Primary Angle Closure

PurposeTo evaluate the posture-related change in intraocular pressure (IOP) of eyes with angle-closure disease and the associated factors.MethodsEyes were prospectively enrolled and divided into three groups: eyes with acute primary angle-closure (APAC), fellow eyes of acute primary angle-closure (FAPAC), and eyes with nonacute primary angle-closure disease (PACD). All of them had been treated with laser peripheral iridotomy. IOP was measured in the sitting, supine, and lateral decubitus positions (LDP) five minutes after posture change. Anterior chamber angle parameters and angle-closure mechanism were evaluated by anterior segment optical coherence tomography.ResultsForty-four eyes were enrolled into each group. APAC eyes showed more LDP-Sitting IOP increase than fellow eyes (5.7 ± 2.7 vs. 2.2 ± 1.4 mm Hg, P < 0.001) and nonacute PACD eyes (3.6 ± 2.0 mm Hg, P < 0.001). LDP-sitting IOP change was higher in eyes with exaggerated lens vault (having shallow anterior chamber and volcano-like iris-lens configuration) than in those without it (APAC: 6.3 ± 2.6 vs. 3.9 ± 2.1 mm Hg, P = 0.011). Linear regression revealed that LDP-sitting IOP change in the APAC group was negatively associated with angle opening distance (AOD), trabecular iris space area, scleral spur angle, and anterior chamber depth (ACD1000). With multivariable stepwise regression analysis, AOD750 remained statistically significant (beta-coefficient = −8.36, P = 0.014).ConclusionsAPAC eyes had significant posture-related IOP changes, associated with narrower angle structures and exaggerated lens vault.     

Differences in central corneal thickness between the paired eyes and the severity of the glaucomatous damage

Purpose

To evaluate whether a difference in central corneal thickness (CCT) between the paired eyes could be associated to worse glaucoma in the thinner cornea eye.

Methods

From 16 different glaucoma centres, at least 50 glaucomatous patients were saved on the Italian Glaucoma Register. Eight hundred and sixteen glaucomatous patients were found in the register. CCT, ophthalmoscopic cup/disc ratio, mean deviation (MD), pattern SD (PSD), and intraocular pressure (IOP). The difference (Δ) between the paired eyes was calculated for all the considered parameters and two subgroups were created on the basis of ΔCCT. Because the difference between the two eyes could be positive or negative, the absolute value of Δ was considered for all the measurements. Three different ΔCCT cutoffs were selected: 10, 15, and 20 μm. Student''s t-test was used to compare the subgroups.

Results

When the entire group was divided in two subgroups using 20 μm as ΔCCT cutoff, no significant difference was found for ΔIOP (−0.38±2.53 (mean±SD) mm Hg and −0.07±2.35 mm Hg, respectively) between the two subgroups. Significant (P<0.001) difference was found for ΔMD (6.58±7.30 and 3.14±4.22 dB, respectively), ΔPSD (3.92±4.01 and 2.16±2.57, respectively), and ΔC/D (0.11±0.14 and 0.08±0.11, respectively) between the two subgroups. No significant correlation was found between ΔCCT and the other parameters.

Conclusion

The ΔCCT between the two eyes could be associated to a worse glaucoma in the thinner cornea eye.     

Childhood glaucoma profile in Dakahelia, Egypt: a retrospective study

AIM: To analyze childhood glaucoma regarding its demographics, presentations, different causes and surgical modalities used among patients in Dakahelia and to apply the Childhood Glaucoma Research Network (CGRN) classification retrospectively to evaluate its convenience. METHODS: A retrospective study in which the medical files of all glaucoma patients <16 years old presented to Mansoura Ophthalmic Center, Mansoura University from 2014 to 2017, were retrieved and analyzed. Collected data included: age, gender, laterality, visual acuity (VA), refraction, intraocular pressure (IOP), corneal diameter, cup-disc ratio, types and number of surgeries and antiglaucomatous drugs (AGD) at the first and last visit. Prevalence of different subtypes was calculated and means of clinical features were compared. RESULTS: A total of 305 eyes of 207 patients were included classified into 6 groups: primary congenital glaucoma (PCG), juvenile open angle glaucoma (JOAG), glaucoma associated with systemic disease, glaucoma associated with ocular anomalies, acquired glaucoma and glaucoma following cataract surgery. PCG was the predominant type (55.1%) followed by acquired glaucoma (29.5%). Males represented 63.8% of the whole studied patients. Glaucoma associated with ocular anomaly group showed the youngest age at diagnosis (21.9±30.0mo). The shortest corneal diameter was recorded in post cataract group (10.4±0.5 mm). Highest cup-disc ratio was found in the PCG group (P<0.0005). Glaucoma associated with systemic disease presented with the highest baseline IOP (34.5±5.0 mm Hg). All the cases with PCG were treated surgically with 21.8% required more than one surgery. The majority of the patients (74.2%) in the acquired group were treated medically. Combined trabeculotomy-trabeculectomy was the most frequent operation done, accounting for 34.5% of all primary surgeries. Ahmed valve implantation comprised 87% of the secondary surgeries. Acquired glaucoma group had the highest percent of eyes with good final Snellen''s VA (69.4%), while glaucoma associated with ocular anomaly group had poorest final VA. CONCLUSION: PCG is the most prevalent type of childhood glaucoma, followed by acquired glaucoma especially traumatic hyphema. Combined trabeculotomy-trabeculectomy and Ahmed valve implantation are the most common surgical interventions. CGRN classification is found to provide a consensus skeleton and is recommended to be integrated in our routine ongoing clinical practice.     

Time of diagnosis, reoperations and longterm results of goniotomy in the treatment of primary congenital glaucoma: a clinical study

Purpose: The aim of our study was to get information about the development of visual acuity, visual field and cupdisc ratio of patients with primary congenital glaucoma after IOP-regulating goniotomy by means of a katamnestic inquiry. The preoperative conditions of IOP, corneal diameter and corneal opacity were related to postoperative findings of visual acuity, visual field and cup-disc ratio reported by the treating ophthalmologists. Methods: 196 patients were contacted, who had a goniotomy in the period from 1965 to 1983 at the University Eye Hospital Würzburg. Out of the 92 returned replies, the address of the treating ophthalmologists could be ascertained from 77 patients. Sixty of the 77 patients fulfilled the inclusion criteria: (1) primary congenital glaucoma and (2) IOP-regulating goniotomy as last surgery. Results: I. In 76% of 106 eyes childhood glaucoma was diagnosed during the first year of life. II. In 72% of 60 eyes/patients with primary congenital glaucoma one goniotomy was sufficient to reach a normal IOP. In 18% a second and in 10% a third goniotomy was necessary, but without influence on the visual outcome. III. Even in the groups of eyes with a preoperative IOP of more than 40 mmHg, preoperative corneal diameter of more than 13 mm and preoperative severe corneal opacity more than 50% reached a visual acuity of 0.4–1.2 and more than 80% had a normal visual field. Only 9% of the eyes showed a cup-disc ratio of 0.6 or more. Conclusions: In primary congenital glaucoma even eyes with high preoperative IOP, large corneal diameters and severe corneal edemas had a good prognosis of visual outcome after goniotomy.Abbreviations CDR cup-disc ratio - LTG low tension glaucoma - PCG primary congenital glaucoma - PG pigmentary glaucoma - VA visual acuity - VF visual field This study was presented in part at the annual meeting of the Association for Research in Vision and Ophthalmology, ARVO, 1996 Fort Lauderdale, Florida, Poster-No. 1903     

Green tea—a new perspective of glaucoma prevention

AIMTo determine how green tea and catechins can affect intraocular pressure (IOP) changes.METHODSTotally 43 young volunteers were included in the study. The experiment was held between noon and 2 p.m. Two extracts—green tea and epigallocatechin gallate (EGCG, 400 mg capsules) and placebo (400 mg capsules) were used in the study. Participants were divided into three groups. Green tea extract group (GT group) had 17 subjects, EGCG extract group 17 subjects, control (placebo) group 9 subjects. IOP was measured with the Icare tonometer before and 30min, 1, 1.5, 2h after the consumption of each extract and placebo. Results were analyzed using the IBM SPSS program. Statistical confidence level P<0.05.RESULTSThe most significant reduction of IOP from the beginning of the experiment was measured after 2h in GT group (left 2.18±3.19 mm Hg, P=0.012; right 2.59±1.97 mm Hg, P<0.000) and after 1h in EGCG extract group (left 2.41±2.98 mm Hg, P<0.004; right 1.94±1.98 mm Hg, P<0.001). In control group no significant changes were measured.CONCLUSIONPeople who have increased IOP or risk factors for glaucoma development, could benefit from drinking green tea or its concentrated extracts in moderate doses.     

Primary congenital glaucoma presenting within the first three months of life in a Bedouin population: prognostic factors

OBJECTIVES: To analyze the final outcome of surgery in Arab-Bedouin children with primary congenital glaucoma (PCG) presenting within the first three months of life, and to search for prognostic factors for success. DESIGN: Retrospective study of all cases with follow-up of at least 24 months. PATIENTS: Twenty-five Arab-Bedouin children (45 eyes) with PCG presenting within the first three months of life who underwent surgical procedures at the Soroka University Medical Center from January 1988 to December 1998. METHODS: Patient's age, family history, main presenting features, data from examinations under anesthesia, including intraocular pressure (IOP), horizontal corneal diameter, and cup/disc (c/d) ratio, and the type of surgery performed were reviewed. MAIN OUTCOME MEASURES: Success of the first operation, defined as final IOP < 21 mm Hg achieved after only one surgical procedure without anti-glaucoma medication, and final outcome, defined as good when IOP was < 21 mm Hg and > 5 mm Hg at the end of a 24-month follow-up period without anti-glaucoma medication, irrespective of the number of procedures performed. RESULTS: At presentation mean IOP was 36.2 +/- 8.0 mm Hg, corneal diameter was 12.62 +/- 0.98 mm, and c/d ratio was 0.41 +/- 0.16. The mean age at first operation was 17 +/- 20 days, and median of 5 days. The mean follow-up period was 37.4 +/- 25.4 months. The success of the first operation performed was not related to the type of operation (P = 0.22), gender (P = 0.47), consanguinity (P = 1.0), family history (P = 0.12), clinical presentation (P = 0.81), or age at first operation (P = 0.38). Eyes with high initial IOP and greater c/d ratio were at a significantly higher risk for failure (P = 0.05, P = 0.04, respectively). A final outcome of IOP under 21 mm Hg and above 5 mm Hg was achieved in 39 eyes (86.5%). There was no statistical association between final outcome and the type of first surgical procedure performed, gender, consanguinity, clinical presentation, and age at first operation. Cases with no family history had a significantly better final outcome (P = 0.05). In multivariate analysis only initial IOP showed borderline significance as an independent risk factor for final outcome (P = 0.06). CONCLUSIONS: Initial high IOP and higher c/d ratio were found to be predictive factors for failure of the first procedure. Final outcome was significantly better in cases with no family history, yet initial IOP was the only independent predictive factor for failure at the final outcome in a multivariate model. Findings of this type have not been previously reported, and they may constitute an important tool in predicting the treatment outcome of very young children with PCG.     

Long-term outcomes and risk factors for failure of glaucoma filtering surgery in eyes with vernal keratoconjunctivitis and steroid-induced glaucoma

Purpose:To report outcomes and assess the risk factors for failure of trabeculectomy (trab), trabeculectomy with mitomycin-C (trabMMC), and combined trabeculectomy with cataract extraction (CT) in vernal keratoconjunctivitis (VKC) eyes with steroid-induced glaucoma (SIG).Methods:Trab was performed in 45 eyes of 30 subjects, trabMMC in 36 eyes of 25 subjects, and CT in 34 eyes of 27 subjects. Success was complete when intraocular pressure (IOP) was between 6 and 21 mm Hg without anti-glaucoma medications (AGM) and qualified with AGM.Results:Median age (14 vs. 16.3 and 17.4 years) was significantly less in the trab cohort (P = 0.007). Majority (88%–93%) were male (P = 0.78). Preoperatively, median duration of steroid usage was >2 years (P = 0.52), mean IOP (32, 29.4, and 28.4; P = 0.26) and median cup:disc ratio (CDR) (0.9; P = 0.27) were similar in the three groups. Complete success (76%, 71%, and 66% at 5 years; P = 0.91), and qualified success (88%, 97%, and 94% at 5 years; P = 1.0) with trab, trabMMC, and CT, respectively, were similar. Preoperative factors significantly associated with qualified failure (multiple logistic regression) were older children, longer duration of VKC, longer duration and mixed type of steroid use (all P < 0.001) and larger CDR (P < 0.02). At the last follow-up, 38% in trab, 33% in trabMMC, and 50% eyes in CT were blind (visual acuity ≤20/400 and/or visual field ≤10°) due to glaucoma (P = 0.33).Conclusion:The surgical success for all three types of surgery was similar at 5-years. Chronic VKC and long-term steroid use were associated with surgical failure. The majority had advanced disease and a significant proportion were blind due to glaucoma.     

Clinical effect of improved viscocanalostomy for the treatment of primary congenital glaucoma

AIM: To evaluate the clinical effect of improved viscocanalostomy in patients with primary congenital glaucoma. METHODS: Retrospective analysis of improved viscocanalostomy was performed on 51 eyes of 42 patients with primary congenital glaucoma. The outcome evaluation included postoperative intraocular pressure(IOP), corneal diameter, cup/disc ratio and complications. All patients were followed up at week 1, month 1, 3, 6 and 12. RESULTS: The results revealed that postoperative IOP was decreased from (38.57±13.61)mmHg to (10.53±3.91)mmHg, (14.89±5.26)mmHg, (15.42±5.11)mmHg, (13.82±3.46)mmHg, (13.16±5.29)mmHg at follow-up time of 1 week, 1, 3, 6, 12 months (P<0.001). The postoperative corneal diameter was decreased significantly (P=0.002); The mean cup/dish ratio wasn’t significantly different (P=0.148) before and after the surgery, the cup/dish ratio of successful surgery was evidently decreased (preoperative 0.7±0.2, postoperative 0.6±0.3, P=0.007), but the complications like as unformed anterior chamber were not observed. The mean follow-up period was 12 months. CONCLUSION: Improved viscocanalostomy improves the clinical effects of the patients with primary congenital glaucoma, such as higher success rates, lower postoperative mean IOP and fewer complications.     

Lowering of intraocular pressure after phacoemulsification in primary open-angle and angle-closure glaucoma: Correlation with lens thickness

Purpose:To assess anterior chamber configuration changes during phacoemulsification in primary angle-closure suspect (PACS/PAC) and primary open-angle glaucoma (POAG).Methods:Prospective observational comparative study of anterior segment optical coherence tomography (AS-OCT) findings before and after phacoemulsification on three groups of patients (PACS/PAC, POAG, and controls). Data were collected over a period of 9 months. Main outcome measures included mean change in anterior chamber depth (ACD), angle opening distance (AOD), and trabecular iris space area (TISA).Results:153 patients (51 PACS/PAC, 51 POAG, and 51 controls) were included in the study. Change in all parameters (ACD, AOD at 500 um, and AOD at 750 um) between the groups demonstrated a greater change in PACS/PAC as compared to POAG and controls. AOD at 750 μm in the temporal quadrant, which has been considered to be having the highest correlation or best representation of the angle, increased in all groups after phacoemulsification (463.59 ± 10.99 vs. 656.27 ± 9.73 mm in PACS; 521.29 ± 16.36 vs. 674.37 ± 8.72 mm in POAG; 549.27 ± 12.40 vs. 702.82 ± 13.04 mm in controls, (P < 0.001). After phacoemulsification, intraocular pressure (IOP) decreased by 2.75 ± 1.17 mm Hg in PACS/PAC (P < 0.001), 2.14 ± 1.33 mm Hg in POAG and 1.90 ± 1.25 mm Hg in controls and it was statistically significant in the PACS group compared to control (P < 0.001).Conclusion: Phacoemulsification with intraocular lens implantation is associated with increase in the ACD and angle parameters and a corresponding decrease in IOP. Findings were more pronounced in PACS/PAC suggesting early phacoemulsification may be a treatment option in this group.     

Morphology of the Trabecular Meshwork and Schlemm's Canal in Posner-Schlossman Syndrome

PurposeThe purpose of this study was to investigate trabecular meshwork (TM) and Schlemm''s canal (SC) morphology in Posner-Schlossman syndrome (PSS).MethodsForty-five patients with PSS were recruited. TM thickness and length as well as SC area and diameter of both affected and fellow eyes were assessed using swept-source optical coherence tomography.ResultsTM thickness (108.24 ± 28.29 µm vs. 89.36 ± 25.82 µm, P = 0.014), SC area (6010.90 ± 1287.54 µm² vs. 5445.69 ± 1368.89 µm², P = 0.003), and SC diameter (239.38 ± 60.17 µm vs. 217.76 ± 60.79 µm, P = 0.010) were significantly greater in the affected eyes. Furthermore, TM thickness (113.32 ± 30.03 µm vs. 89.00 ± 26.99 µm, P = 0.046), SC area (6216.32 ± 1267.87 µm² vs. 5476.40 ± 1390.15 µm², P = 0.001), and SC diameter (246.82 ± 64.12 vs. 212.53 ± 64.29 µm, P = 0.001) were significantly greater in the affected eyes than in the fellow eyes in the ocular hypertension (OHT) subgroup (affected eye with intraocular pressure [IOP] > 21 mm Hg). However, those differences were not noted in the ocular normal tension (ONT) subgroup (affected eye with IOP ≤ 21 mm Hg, all P > 0.05).ConclusionsTM edema might play a role in the IOP elevation in PSS. The edematous TM could make controlling IOP of the affected eyes difficult. When TM edema is relieved, IOP of the affected eyes can reduce to normal spontaneously or with IOP-lowing medications.     

Potential Mechanisms of Intraocular Pressure Reduction by Micropulse Transscleral Cyclophotocoagulation in Rabbit Eyes

PurposeTo evaluate the histological changes associated with, and the potential mechanisms of, intraocular pressure (IOP) reduction by micropulse cyclophotocoagulation (MP-CPC) in rabbit eyes.MethodsMP-CPC was performed on the right eyes of Dutch belted rabbits, whereas the left eyes served as controls. The laser power settings were 250, 500, 750, 1000, 1500, and 2000 mW, 10 seconds per sweep, 100 seconds in total. IOP, outflow facility, and uveoscleral outflow tract imaging, using a fluorescent tracer, were examined at one week after MP-CPC. Changes of morphology and protein expressions in the outflow tissues, conjunctiva, and sclera were also evaluated.ResultsSignificant reductions in IOP after MP-CPC were observed at 500 to 1000 mW (P = 0.036 and P = 0.014, respectively). The pre-MP-CPC IOP was 11.35 ± 0.41 mm Hg. At one week after surgery, the respective IOP values in the eyes treated at 500 mW and 1000 mW were 9.45 ± 0.49 mm Hg and 7.4 ± 0.27 mm Hg, respectively. Severe ciliary body damage was observed at 1500 to 2000 mW. MMP1–3 and fibronectin expression levels in the outflow tract and ciliary body were upregulated after MP-CPC. The α-smooth muscle actin (α-SMA) was upregulated at higher power levels. MP-CPC significantly increased uveoscleral outflow, whereas the outflow facility did not change. The α-SMA, collagen, and fibronectin were significantly upregulated in the subconjunctiva and sclera.ConclusionsReactive fibrotic responses were observed in the outflow tract, conjunctiva, and sclera after MP-CPC. A potential mechanism of IOP reduction by MP-CPC in pigmented rabbit eyes may involve increased uveoscleral outflow related to MMP upregulation.     

The Effect of a Diving Mask on Intraocular Pressure in a Healthy Population

PurposeSwimming goggles increase the intraocular pressure (IOP) via the periorbital frame pressure and suction effect. In comparison, diving masks have a larger frame rim and incorporate the nose. The exact effect(s) of diving masks on IOP is unknown. This study evaluates the influence of diving masks on IOP in normal, healthy subjects.MethodsTonometry was performed in both eyes of all subjects with an AVIA^®Tono-Pen by a single investigator. Measurements were taken at baseline without the diving mask and with the subjects wearing a small-volume, double-window diving mask, but with the mask lenses removed. Two IOP readings in each eye were measured, and an additional reading was measured if the difference between the initial 2 was ≥2 mm Hg. Central corneal thickness (CCT) was also measured in each eye, using a contact pachymeter (OcuScan^®Alcon).ResultsForty eyes of 20 healthy volunteers (age 29.7 ± 9.3 years; range 21–52) were included. The mean CCT was 544.4 ± 43.5 µm. The mean IOP before the diving mask was worn had been 17.23 ± 2.18 mm Hg (n = 40). The IOP decreased by 0.43 mm Hg (p $1003c; 0.05) to 16.80 ± 2.57 mm Hg after the diving mask had been put on. There was no correlation between IOP change and age (r = 0.143, p = 0.337), gender (r = −0.174, p = 0.283) or CCT (r = −0.123, p = 0.445).ConclusionThere was no increase in IOP after the diving mask had been worn. A small but statistically significant decrease in IOP was observed. This study demonstrates that unlike swimming goggles, the strap tension and frame pressure on the periorbital tissue from a diving mask does not increase IOP. Diving masks may be a suitable alternative to swimming goggles for patients with advanced glaucoma or glaucoma filtration surgery.     

黏弹物质小管扩张术联合90°小梁切开术治疗原发性婴幼儿型青光眼

目的：评价黏弹物质小管扩张术联合90°小梁切开术治疗原发性婴幼儿型青光眼( prilary congenital glaucola, PCG)的临床疗效。
　　方法：采用前瞻性随机对照临床试验研究,将37例50眼首次行手术治疗的原发性婴幼儿型青光眼患者分为两组,试验组25眼行黏弹物质小管扩张术联合90°小梁切开术;对照组25眼行180°小梁切开术。观察比较的指标包括：术前及术后眼内压( intraocular pressure,IOP)、角膜直径、杯/盘比(C/D),随访时间点为1wk,1、3、6lo。患儿均在水合氯醛灌肠下用Schiots眼压计测量眼压、用双脚圆规测量角膜的横径,用检眼镜记录眼底杯盘比值。
　　结果：术后随访6lo,黏弹物质小管扩张术联合90°小梁切开术组术后1wk,1、3、6lo的平均眼压分别为7.51±3.68、11.79±1.84、13.97±2.76、14.51±0.97llHg,180°小梁切开术组分别为8.47±2.66、13.88±6.32、15.74±3.20、16.51±2.44llHg,均较术前眼压30.74±4.68、31.96±5.15 llHg 明显降低,差异均有显著统计学意义( P<0.01);黏弹物质小管扩张术联合90°小梁切开术组术后3 lo平均角膜横径较术前明显减少,差异有统计学意义( P<0.05);术后22眼的杯盘比减小,28眼的杯盘比不进展。手术成功者其杯/盘比值明显减小(术前0.72±0.19,术后0.60±0.24,P=0.007);患者50眼中,术中前房出血11眼(22%),前房是否出血与术后眼压降低情况无关。余患者术后均未出现无浅前房、低眼压、角膜后弹力膜脱离、脉络膜脱离、玻璃体脱出、虹膜粘连及眼内感染等并发症。
　　结论：黏弹物质小管扩张术联合90°小梁切开术治疗原发性婴幼儿型青光眼,具有术后眼压控制效果好,术后并发症发生率低,安全性高的特点。     

Secondary developmental glaucoma in eyes with congenital aphakia

Purpose:To describe the clinical spectrum and management of glaucoma in congenital aphakia.Methods:The demographics and clinical spectrum of eyes with congenital aphakia with and without glaucoma were compared, and management outcomes of congenital aphakia cases with glaucoma were studied retrospectively between April 2000 and June 2020.Results:There were a total of 168 eyes (84 subjects) with a diagnosis of congenital aphakia, of which 29 eyes of 18 subjects were diagnosed with glaucoma. Corneal opacity was the presenting complaint in 26/29 eyes with glaucoma and 139/139 eyes without glaucoma. The (interquartile range (IQR)) horizontal corneal diameter was 10.5mm (IQR, 9.0-12.5) and 8mm (IQR, 5-10) in eyes with and without glaucoma (P = 0.01), respectively. The median (IQR) axial length was 17.5mm (IQR, 13.5-19.5) and 15mm (IQR, 14-16) mm in eyes with and without glaucoma (P = 0.03), respectively. Nineteen eyes with glaucoma had adequate intraocular pressure (IOP) control with one medication. Three eyes underwent transscleral diode cyclophotocoagulation and maintained IOP without medications. Three eyes underwent trabeculectomy and trabeculotomy, trabeculectomy followed by penetrating keratoplasty, and trabeculectomy, respectively, of which two eyes became phthisical. At the last follow-up, the median (IQR) IOP was 14 mm Hg (IQR, 14-17) Hg. The median (IQR) follow-up duration was 4.53 months (IQR, 2.03- 48.06).Conclusion:One-fifth of the eyes with congenital aphakia had secondary developmental glaucoma. The corneal diameter and axial lengths were higher in the eyes with glaucoma compared to eyes without glaucoma. Medical management is the preferred short-term mode of IOP control. Transscleral cyclophotocoagulation may be preferred over surgical intervention.