Optical low-coherence reflectometry enables preoperative detection of zonular weakness in pseudoexfoliation syndrome

Risk factors for a phacodonesis surprise during cataract surgery in patients with pseudoexfoliation

PURPOSE

To evaluate the association of different pre-operative parameters with surprise phacodonesis during cataract surgery among patients with pseudoexfoliation (PXF).

MATERIALS AND METHODS

This is a retrospective charts review of all PXF patients who underwent cataract surgery between the years 2013 and 2018. Pre-operative parameters (demographics, biometry, intraocular pressure (IOP), endothelial cell count, pupil size, cataract density, glaucoma status, cup to disc ratio, number of glaucoma medications, prior intra-vitreous injections, risk for intraoperative floppy iris syndrome) were compared between patients with and without surprise phacodonesis. Binary logistic regression was used to calculate the predictive value of each parameter.

RESULTS

Out of 396 surgical cases with computerized pre-operative assessment, we included 127 eyes of 120 PXF patients without evidence of phacodonesis preoperatively. The mean age was 77.8 ± 12.0 years, 63 (52.7%) were male, and 106 (84.2%) underwent phacoemulsification surgery. We identified 10 cases of surprise phacodonesis during surgery (8.2%). Compared to PXF cases without intraoperative phacodonesis, they had higher pre-operative IOP (23.0 ± 11.0 mmHg vs. 14.9 ± 3.8 mmHg, p < 0.001) and a higher rate of B scan use due to dense cataract obscuring posterior pole evaluation [4 (40%) vs. 15 (12.8%), p = 0.04]. Multivariant binary logistic regression confirmed that only baseline IOP contributed to the prediction of surprise phacodonesis (OR 1.22 CI 1.04-1.43, p = 0.014).

CONCLUSIONS

Among patients with PXF undergoing cataract surgery, elevated IOP and poor posterior segment visibility requiring B scan use were associated with zonular instability putting these patients at risk for intra-operative complications.

Do Gender, Age, Body Mass and Height Influence Eye Biometrical Properties in Young Adults? A Pilot Study

BACKGROUND

Do gender, age, body mass and height influence eye biometrical properties in young adults?

METHODS

A total of 155 eyes (92 female, 63 male) of healthy subjects between the ages of 18 and 39 years were included in the study. The subjects' gender and age were recorded, and their body mass, height and biometrical properties of the eyes were measured.

RESULTS

The male subjects had significantly thicker and flatter corneas and lower minimal rim-to-disk ratios than the female subjects did. In both genders, age showed strong, negative correlations with anterior chamber depth and pupil diameter and a positive correlation with lens thickness. We also found significant, negative correlations between body height and mass with keratometry measurements, negative correlations between body height and optic disk rim area and rim volume, and positive correlations between body mass and axial length in both genders.

CONCLUSIONS

Biometric eye parameters differ among people. In addition to age and gender, which are usually taken into consideration when interpreting ocular biometry findings, we strongly suggest that body height and mass should be also routinely considered when interpreting eye biometry data, as these factors have an impact on ocular biometry.

Predicting zonular strength based on maximum pupillary mydriasis in patients with pseudoexfoliation syndrome

Pseudoexfoliation Syndrome (PXFS) is considered a systemic disorder with significant ocular manifestations ranging from corneal decompensation, non-dilating pupil, zonular weakness, subluxated lens, and glaucoma. PXFS may lead to increased complications during routine cataract surgery. Zonular dialysis is a common complication during or after cataract surgery in such patients. However, not all patients with pseudoexfoliation are at a higher risk. We hypothesize that there is an inverse correlation between the maximum pupillary dilation and the degree of zonular disintegration. Available evidence supporting the hypothesis is discussed. We propose a new clinical classification for predicting the zonular strength based on the maximum pupillary dilation so that it can serve as a guide to identify PXFS patients who are at high risk of complications during or after cataract surgery.

SPECIFIC CHARACTERISTICS OF OCULAR BIOMETRIC FACTORS IN GLAUCOMATOUS PATIENTS WITH PSEUDOEXFOLIATIVE SYNDROME AS MEASURED BY OPTICAL LOW-COHERENCE REFLECTOMETRY

The aim of the study was to assess biometric factor aberrations and differences among groups of eyes with cataract and pseudoexfoliative syndrome, cataract and pseudoexfoliative glaucoma, and cataract and primary open-angle glaucoma (POAG), and to determine biometric factors of the eye specific for the group of glaucomatous patients with pseudoexfoliative syndrome by use of optical low-coherence reflectometry. This retrospective study included 72 patients, and the study sample of 102 eyes was divided into the following three groups according to diagnosis: 29 eyes with pseudoexfoliative syndrome and cataract; 36 eyes with POAG and cataract; and 37 eyes with pseudoexfoliative glaucoma and cataract. Data on biometric measurements (central corneal thickness, pupillary diameter, anterior chamber depth, lens thickness, axial length, retinal thickness, astigmatism and white-to-white) obtained by use of optical low-coherence reflectometry on a Lenstar LS 900® (Haag-Streit International) were collected and analyzed by thorough survey of medical documentation of patients scheduled for cataract surgery at Department of Ophthalmology, Sveti Duh University Hospital in Zagreb, Croatia. Comparative analysis of the groups yielded statistically significant differences in central corneal thickness (F2/99=7.066; p=0.001) and lens thickness (F2/96=5.133; p=0.008). The group of eyes diagnosed with pseudoexfoliative glaucoma and cataract had a significantly thinner cornea as compared with the other two groups and a significantly thicker lens as compared with the group of eyes with POAG and cataract. In conclusion, optical low-coherence reflectometry revealed differences in biometric factors among the three groups of eyes, with a statistically significantly thinner cornea and thicker lens in the group of glaucomatous patients with pseudoexfoliative syndrome.

Short-term fluctuation of lens corneal distance and clinical correlation with phacodonesis

BACKGROUND

To analyze the role of short-term lens-corneal distance (LCD) fluctuation in quantifying preoperative phacodonesis and predicting intraoperative zonular weakness.

METHODS

Patients were divided into control (lens without clinical phacodonesis) and study (lens with suspicious and clinical phacodonesis) groups for evaluation. Slit-lamp examination followed by IOLMaster (Carl Zeiss) for LCD assessment was performed. Five readings were taken at five time points (0 s, 15 s, 30 s, 45 s & 60 s) continuously over a minute (short term) for the LCD fluctuation calculation.

RESULTS

A total of 135 eyes (82 controls and 53 study) were assessed. Study group included 32 (60.3%) suspicious and 21 (39.6%) moderate to severe phacodonesis. There was difference between the control and study eyes (p = 0.000) in short-term LCD fluctuation. Twenty-one study eyes (39.6%) showed LCD difference > 1 mm, including 11 eyes (52.3%) with > 2 mm. There was a difference in LCD with respect to severity of phacodonesis (p = 0.000). In the study eyes, 13 eyes underwent glued IOL implantation (clinical phacodonesis - ten, suspicious phacodonesis - three), and two eyes (suspicious phacodonesis) had glued capsular hook. Thirteen eyes (clinical phacodonesis - ten, suspicious phacodonesis - three) required intraoperative vitrectomy due to vitreous ingress. Intraoperative zonular weakness in 62.5% of eyes with suspicious donesis and association (Chi-square = 0.000) of weakness with preoperative LCD fluctuation was noted.

CONCLUSIONS

Short-term lens-corneal distance fluctuation can be used as a parameter for quantifying lens stability and as an aid in assessing the intraoperative risk.

Characteristics of the Anterior Segment Biometry and Corneal Endothelium in Eyes with Pseudoexfoliation Syndrome and Senile Cataract

Objectives:

To evaluate the anterior segment biometric features and corneal endothelial changes in eyes with pseudoexfoliation (PEX) syndrome and senile cataract.

Materials and Methods:

The central corneal thickness, anterior chamber depth (ACD), pupil diameter, lens thickness, endothelial cell density (ECD), and percentages of polymegathism and pleomorphism of 52 subjects with PEX and cataract were compared with 51 age- and gender-matched control subjects with cataract using optical low-coherence reflectometry (OLCR, Lenstar LS 900; Haag Streit AG, Switzerland) and in-vivo confocal microscopy (Confo Scan 4, Nidek Co. Ltd, Osaka, Japan). Nineteen subjects with PEX syndrome had glaucoma and were using anti-glaucoma medications. Only one eye of the subjects was used in statistical analysis and a p value less than 0.05 was considered statistically significant.

Results:

None of the OLCR parameters reached statistically significant differences among the 3 groups (ANOVA p>0.05). The percentage of eyes with ACD <2.5 mm was 13.7% in the control group, 24.2% in PEX eyes without glaucoma and 21.1% in PEX eyes with glaucoma, with no statistically significant differences (p=0.45). There was a significant difference in mean ECD among the 3 groups (ANOVA p=0.02), whereas no differences could be found in respect to polymegathism and pleomorphism (p>0.05). Mean ECD was significantly lower in the PEX glaucoma group (2,199.5±176.8 cells/mm2) than the control group (2,363±229.3 cells/mm2) (p=0.02), whereas no difference was found in mean ECD of PEX eyes without glaucoma and the control group (p=0.42). ECD was less than 2,000 cells/mm2 in 15.8% of PEX subjects with glaucoma, 9.8% of control subjects and 6.1% of PEX eyes without glaucoma, with no statistically significant difference (p=0.52).

Conclusion:

As eyes with both PEX glaucoma and cataract seem to be associated with decreased endothelial cell number, specular or confocal microscopy screening should be done for the patients scheduled for intraocular surgery.

Anterior Segment Optical Coherence Tomography Assessment After Laser Capsulotomy in Pseudophakic Eyes With Pseudoexfoliation

PURPOSE

To assess changes in anterior-chamber depth (ACD) and angle width after neodymium:yttrium aluminum garnet (Nd:YAG) laser capsulotomy pseudophakia in eyes with pseudoexfoliation (PEX).

METHODS

This prospective and interventional case series study included 25 pseudophakic eyes of 25 patients with PEX and 26 pseudophakic eyes of 26 patients without PEX scheduled for Nd:YAG laser capsulotomy in a single institution. Anterior-chamber depth and angle width were measured with anterior segment optical coherence tomography before and three days after Nd:YAG laser capsulotomy. Preoperative and postoperative measurements of ACD and angle width included the angle opening distance (AOD), measured as the perpendicular distance from the trabecular meshwork at 500 and 750 mm anterior to the scleral spur to the anterior iris surface (AOD500 and AOD750, respectively) and anterior-chamber angle (ACA) in the nasal and temporal quadrants. Main outcome measures were the changes in ACD and angle width parameters.

RESULTS

The mean ACD, AOD500, AOD750, and ACA (nasal and temporal) measurements were 3.67±0.12 mm, 0.63±0.05 mm and 0.65±0.05 mm, 0.67±0.06 mm and 0.77±0.04 mm, 35.25±1.69° and 35.37±1.68° in eyes with PEX and 3.73±0.11 mm, 0.6±0.05 mm and 0.63±0.05 mm, 0.66±0.06 mm and 0.74±0.06 mm, 34.24±1.6° and 34.6±1.47° in control eyes, respectively (P>0.05 for all). After Nd:YAG laser capsulotomy, mean ACD, AOD500, AOD750, and ACA (nasal and temporal) measurements were 3.76±0.09 mm, 0.73±0.05 mm and 0.76±0.05 mm, 0.75±0.06 mm and 0.87±0.04 mm, 36.82±1.46° and 35.06±1.52° in eyes with PEX and 3.77±0.1 mm, 0.68±0.06 mm and 0.72±0.06 mm, 0.72±0.05 mm and 0.84±0.06 mm, 34.95±1.4° and 35.79±1.36° in control eyes, respectively (P=0.811, P=0.019, P=0.021, P=0.109, P=0.126, P=0.001, and P=0.01, respectively).

CONCLUSIONS

The depth and width of the anterior chamber in eyes with PEX and in control eyes increased significantly after Nd:YAG laser capsulotomy. The change in the width of the anterior chamber in eyes PEX was statistically significant comparing control eyes.

Biometric and intraocular pressure change after cataract surgery

PURPOSE

To evaluate changes in ocular biometric parameters with optical biometry and intraocular pressure (IOP) by Goldmann tonometry after uneventful phacoemulsification in normotensive eyes.

METHODS

This prospective study was composed of 117 eyes of 117 patients who had undergone uncomplicated phacoemulsification and foldable intraocular lens implantation. The measurements were obtained preoperatively and 1 month postoperatively. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), pupil diameter (PD), and lens thickness were measured by the LenStar optical biometer, and IOP was measured by Goldmann applanation tonometry. The relationships between IOP change and ocular biometric parameters were evaluated.

RESULTS

Mean age was 64.73 ± 10.83 years; 45 patients were women (38.46%) and 72 patients were men (61.54%). Comparing preoperative and postoperative 1-month measurements, the mean AL, PD, and IOP decreased (p < 0.01), whereas ACD (p < 0.01) and CCT (p > 0.05) increased. Intraocular pressure change correlated positively with AL change (p < 0.05) and PD change (p < 0.05) and preoperative IOP (p < 0.01) and preoperative CCT (p < 0.05). Anterior chamber depth change correlated positively with preoperative ACD (p < 0.01) and negatively with preoperative PD (p < 0.05). Pupil diameter change positively correlated with preoperative PD (p < 0.01). Regression analyses showed that preoperative IOP significantly associated with postoperative IOP reduction according to the standardized coefficient beta (-0.649).

CONCLUSIONS

Anterior segment morphometry changed and IOP decreased after phacoemulsification. The preoperative IOP may be the best parameter for estimating postoperative IOP reduction.

Evaluation of Optical Low Coherence Reflectometry Parameters in Patients with Exfoliation Syndrome

Purpose. To evaluate optical low coherence reflectometry (OLCR) parameters in patients with exfoliation syndrome (EXS) undergoing cataract surgery. Methods. Forty-seven eyes of 47 patients with EXS (Group 1), and 55 eyes of 55 healthy subjects (Group 2) were included in the study. Anterior chamber depth (ACD), lens thickness (LT), axial length (AL), central corneal thickness (CCT), horizontal corneal length (HCL), and pupil diameter (PD) parameters were measured by OLCR (Lenstar LS 900, Haag-Streit) and compared between groups. Shapiro-Wilk test and Mann Whitney U tests were used for statistical analyses. Results. The mean ACD, HCL, and PD values were significantly lower in EXS group than in healthy subjects (P = 0.01, P = 0.04, and P < 0.001, resp.). The mean LT was significantly higher in EXS group than in healthy subjects (P = 0.007). There was no significant difference between groups in means of AXL and CCT. Conclusions. According to OLCR measures, eyes with EXS have shallower ACD, smaller PD, thicker LT, shorter HCL, and no significantly different CCT levels.

Investigation of phacoemulsification on exfoliation syndrome combined cataract with different nuclear hardness

PURPOSE

We investigated the clinical staging and management of cataracts to decrease the incidence of complications of phacoemulsification and improve the postoperative visual function of patients with exfoliation syndrome (XFS) with cataract.

METHODS

Cataracts with XFS were divided into early, middle, and late stages using the Emery-Little lens opacities classification system. Phacoemulsification and intraocular lens (IOL) implantation were performed in all eyes. The incidences of intraoperative and early postoperative complications of phacoemulsification were compared, and differences in the outcomes of phacoemulsification were evaluated.

RESULTS

There were 23, 31, and 34 eyes with early-, middle- and late-stage XFS, respectively. The mean ultrasound time, cumulative dissipated energy, and incidence of moderate to severe corneal edema and wound burn in the late-stage group were significantly higher than in the early- and middle-stage groups (p&lt;0.05). The incidence of zonular dehiscence, capsular rupture, vitreous loss, and iritis were not significant among the 3 groups (p&gt;0.05). Intraocular pressure rise in the early postoperative period and the level of optic atrophy in the late-stage group were significantly higher than in the other 2 groups (p&lt;0.05). The gain in visual acuity in the early- and middle-stage groups after surgery was better than in the late-stage group of XFS, and the difference was statistically significant (p&lt;0.05).

CONCLUSIONS

The clinical staging of cataract with XFS contributed to the choice of operation time and its management. Phacoemulsification and IOL implantation in early- and middle-stage XFS induced fewer complications and led to better recovery of visual function after surgery.