Effect of misalignment at different orientations associated with angle κ on optical performance of aspheric intraocular lenses with different surface designs.

Intraocular lens (IOL) misalignment and angle κ have had significant negative impact on post-operative quality of vision. ZEMAX software has been used to imitate the optical performance of pseudophakic eyes with different IOL surface designs at different orientations of IOL misalignment (decentration of 0.4 mm and tilt of 7°, and with the existence of 0.5 mm angle κ). We found that an aspheric balanced curve optic surface maintained better optical performance via inducing less coma aberration. Coma aberration played an unexpectedly important role in the optical performance. With angle κ, the impact of IOL misalignment on visual quality was associated with the orientation of decentration and tilt, indicating that the coma compensation also took effect in pseudophakic eyes. Due to the high incidence of post-operative IOL misalignment, our results provide evidence of the importance of considering personalized angle κ before cataract surgery for patients.

Association of peripheral anterior synechiae with anterior segment parameters in eyes with primary angle closure glaucoma.

To investigate the association of peripheral anterior synechiae (PAS) with intraocular pressure (IOP) and anterior-segment parameters in subjects with primary angle-closure glaucoma (PACG). A total of 267 subjects with PACG were recruited and underwent gonioscopy and anterior-segment optical coherence tomography (ASOCT). Customized software was used to measure ASOCT parameters, including angle opening distance (AOD750) and trabecular-iris-space-area (TISA750) at 750 µm from the scleral spur, anterior chamber depth, width, area and volume (ACD, ACW, ACA, ACV), iris thickness (IT750), iris area (IAREA), and lens vault (LV). Presenting IOP was defined as the first IOP reading before the initiation of IOP-lowering treatment. The mean age of the 267 subjects was 67.0 ± 8.9 years, 140 (52.4%) were male, and 246 (92.1%) were of Chinese ethnicity. PAS was present in 122 (45.7%) subjects, and was most frequently found in the superior quadrant (79.5%). Subjects with PAS had greater presenting IOP (28.7 ± 12.9 vs 22.4 ± 9.7 mmHg, p < 0.001), narrower AOD750 (p < 0.001), smaller TISA750 (p < 0.001), ACD (p = 0.04), ACA (p = 0.02), ACV (p = 0.01) and larger LV (p = 0.01) compared to PACG eyes without PAS. No significant differences were noted for iris parameters. A multivariate logistic regression analysis showed that higher presenting IOP (ß = 0.20, p < 0.001), worse visual field mean deviation (ß = - 0.20, p = 0.01) and narrower AOD750 (ß = - 0.25, p = 0.03) were the only parameters that significantly correlated with the extent of PAS in clock hours. Almost one-half of the subjects with PACG demonstrated PAS; these eyes were associated with higher presenting IOP, smaller anterior segment dimensions and more severe disease.

Penetrating Keratoplasty in Infants With Peters Anomaly: Visual and Graft Outcomes.

PURPOSE: To determine the prevalence of survival of corneal grafts and visual outcomes of primary penetrating keratoplasty (PK) in infants with Peters anomaly (PA) in Beijing, China. METHODS: Twenty-nine patients (37 eyes) with PA who underwent PK before the age of 1 year were included. Optical correction for all eyes and occlusion therapy of amblyopia for a unilateral opacity were performed 2 weeks after suture removal. All infants underwent assessment of visual acuity after surgery using Teller Acuity Cards. Survival probabilities were estimated using the Kaplan-Meier method and log-rank test. Visual outcomes and prognosis factors were analyzed using the χ2 test. RESULTS: The mean age of 29 infants undergoing primary PK was 5.7 ± 2.3 months. The mean follow-up duration was 18.0 ± 3.0 months. Twenty-seven (73.0%) of 37 grafts retained full clarity at final follow-up. Visual acuity above ambulatory was achieved in 67.6% (25/37) and >20/260 was achieved in 48.6% (18/37) of cases. Of all surgical indications, vascularized PA I (50.0%, 6/12) and PA II (18.2%, 2/11) showed a lower proportion achieving visual acuity >20/260 than nonvascularized PA I (71.4%, 10/14) (P = 0.030 < 0.05). There was no significant difference in the prevalence of graft survival and vision outcome between infants younger than 6 months and older than >6 months. CONCLUSIONS: For infants with PA who underwent PK, the prevalence of graft survival and visual acuity were related mainly to the indication. The main risk factors were corneal vascularization and an abnormal lens.

Genetic background modifies vulnerability to glaucoma-related phenotypes in Lmx1b mutant mice.

Variants in the LIM homeobox transcription factor 1-beta (LMX1B) gene predispose individuals to elevated intraocular pressure (IOP), a key risk factor for glaucoma. However, the effect of LMX1B mutations varies widely between individuals. To better understand the mechanisms underlying LMX1B-related phenotypes and individual differences, we backcrossed the Lmx1bV265D (also known as Lmx1bIcst ) allele onto the C57BL/6J (B6), 129/Sj (129), C3A/BLiA-Pde6b+ /J (C3H) and DBA/2J-Gpnmb+ (D2-G) mouse strain backgrounds. Strain background had a significant effect on the onset and severity of ocular phenotypes in Lmx1bV265D/+ mutant mice. Mice of the B6 background were the most susceptible to developing abnormal IOP distribution, severe anterior segment developmental anomalies (including malformed eccentric pupils, iridocorneal strands and corneal abnormalities) and glaucomatous nerve damage. By contrast, Lmx1bV265D mice of the 129 background were the most resistant to developing anterior segment abnormalities, had less severe IOP elevation than B6 mutants at young ages and showed no detectable nerve damage. To identify genetic modifiers of susceptibility to Lmx1bV265D -induced glaucoma-associated phenotypes, we performed a mapping cross between mice of the B6 (susceptible) and 129 (resistant) backgrounds. We identified a modifier locus on Chromosome 18, with the 129 allele(s) substantially lessening severity of ocular phenotypes, as confirmed by congenic analysis. By demonstrating a clear effect of genetic background in modulating Lmx1b-induced phenotypes, providing a panel of strains with different phenotypic severities and identifying a modifier locus, this study lays a foundation for better understanding the roles of LMX1B in glaucoma with the goal of developing new treatments.

Anterior scleral thickness and shape changes with different levels of simulated convergence.

PURPOSE: Convergence plays a fundamental role in the performance of near visual tasks. We measured the effect of two levels of convergence on anterior scleral thickness and shape in emmetropes, low to moderate myopes and high myopes. METHODS: Forty-five healthy young adults aged between 18 and 35 years including 15 emmetropes, 15 low/moderate myopes, and 15 high myopes were recruited. Anterior segment optical coherence tomography and eye surface profilometry were used to evaluate the anterior scleral thickness (nasal only, n = 42) and shape (n = 40), before and during two visual tasks involving 9° and 18° convergence, in those participants with complete and reliable data. RESULTS: Convergence led to a thickening of the total anterior eye wall (5.9 ± 1.4 µm) and forward movement (10 ± 2 µm) of the nasal anterior scleral surface (both p < 0.001). Larger changes were found at 18° than at 9° convergence and in more peripheral nasal scleral regions. There was a significant association between total wall thickening and forward movement of the scleral surface. Refractive group was not a significant main effect, but there were significant interactions between refractive group and the thickness changes with convergence in different scleral regions. CONCLUSION: During convergence, the biomechanical forces acting on the eye lead to nasal anterior scleral thickening and forward movement of the nasal scleral surface.

Phacoemulsification, visco-goniosynechialysis, and goniotomy in patients with primary angle-closure glaucoma: A comparative study.

OBJECTIVE: The aim of this study was to evaluate the effects of goniotomy on patients with primary angle-closure glaucoma who underwent "phacoemulsification and visco-goniosynechialysis." MATERIALS AND METHODS: This prospective randomized clinical trial was carried out on 63 eyes of 61 patients (48-85 years) with primary angle-closure glaucoma who were enrolled. The subjects were randomly assigned into two groups. In the first group (32 eyes) and the second group (31 eyes), the patients underwent "phacoemulsification + visco-goniosynechialysis + goniotomy" and "phacoemulsification + visco-goniosynechialysis," respectively. Intraocular pressure and antiglaucoma medication were evaluated (1 week, as well as 1, 3, and 6 months after the surgery). Anterior segment optical coherence tomography parameters (Casia, Tomey, USA) and goniotomy were evaluated preoperatively and 6 months after the surgery. RESULTS: The mean intraocular pressure lowering the effects in the "phacoemulsification + visco-goniosynechialysis + goniotomy" group was higher than that in the "phacoemulsification + visco-goniosynechialysis" group (6.93 and 4.6, respectively). Furthermore, the difference in intraocular pressure between the two groups was significant at 3 months (P = 0.014) and 6 months (P = 0.021) after the surgery. There was no difference in anterior segment optical coherence tomography findings before the intervention; however, after the intervention, the anterior segment optical coherence tomography indices were significantly different between the two groups. Moreover, the difference in "phacoemulsification + visco-goniosynechialysis + goniotomy" indices was more than the changes in the "phacoemulsification + visco-goniosynechialysis" group. CONCLUSION: The results of this study showed that phacoemulsification + visco-goniosynechialysis + goniotomy is a more effective surgery than phacoemulsification + visco-goniosynechialysis alone in undercounted primary angle-closure glaucoma.

Evaluation of CorvisST biomechanical parameters and anterior segment optical coherence tomography for diagnosing forme fruste keratoconus.

PURPOSE: To investigate the utility of biomechanical property measurements using a Scheimpflug-based tonometer (SBT) and/or anterior segment optical coherence tomography (AS-OCT) for diagnosing forme fruste keratoconus (FFK). METHODS: In this retrospective interventional case series, 23 eyes with FFK of 23 consecutive patients and 52 eyes of 52 healthy volunteers who visited our keratoconus outpatient clinic were enrolled. Logistic regression analysis was conducted to determine the causal relationship between FFK diagnosis and each parameter. RESULTS: When only SBT was used, the corneal stiffness parameter, stiffness parameter A1 (SP-A1) and the corneal velocity at first applanation were selected as explanatory variables, and sensitivity, specificity and area under the receiver operating characteristic curve (AUROC) were 82.9%, 86.9% and 0.938, respectively. When only AS-OCT parameters were used, the posterior corneal asymmetric component and central corneal thickness were selected, and the sensitivity, specificity and AUROC were 82.6%, 94.2% and 0.893, respectively. When parameters from both methods were used, SP-A1 and the posterior corneal asymmetry component derived from Fourier analysis were selected as explanatory variables, and sensitivity, specificity and AUROC were 91.30%, 90.38% and 0.947, respectively. No significant differences in AUROC were observed between diagnoses using each device and the combination of both devices (AS-OCT versus SBT, p = 0.314; integrated parameters versus AS-OCT, p = 0.081; integrated parameters versus SBT, p = 0.234). CONCLUSION: Optimization of SBT and AS-OCT parameters allowed for the diagnosis of FFK at a clinically usable level. Forme fruste keratoconus (FFK) diagnosis integrating biomechanical properties with AS-OCT showed no superiority compared to diagnosis based on a single device.

Long-Term Visual Outcomes and Clinical Course of Patients With Peters Anomaly.

PURPOSE: To present long-term clinical and visual outcomes of patients with Peters anomaly. METHODS: The charts of all patients diagnosed with Peters anomaly from January 2000 to December 2012 were reviewed retrospectively. Peters anomaly was classified as type I (with no lens involvement) or type II (presence of keratolenticular adhesions or cataract), with further severity grading to mild, moderate, and severe disease depending on corneal opacity location and size. Mild cases were observed. Moderate cases were managed with pupillary dilation either pharmacologically or surgically. Penetrating keratoplasty (PKP) was reserved for more severe opacity. The main outcome measures were final best spectacle-corrected visual acuity (BSCVA), incidence of glaucoma, graft survival, and nystagmus rates. RESULTS: Sixty eyes of 40 patients were included in the study. The median age of patients at presentation was 0.5 ± 20.7 months (range, 0.0-111.0 months), with a mean follow-up time of 75.8 ± 52.9 months (range, 12.1-225.3 months). Overall, final best spectacle-corrected visual acuity ranged from 0.1 logMAR to no light perception with 33 eyes (55.9%) achieving vision of 1.0 logMAR or better. Clear grafts at the last follow-up were obtained in 67.6% (25/37) of transplanted eyes, 76.0% (19/25) in Peters type I, and 50.0% (6/12) in Peters type II (P = 0.11). The probability of a clear graft at 10 years was 74.2% and 38.9% for type I and type II, respectively. Glaucoma was diagnosed in 33.3% eyes, 90.0% of which occurred after PKP. Nystagmus was highly associated with PKP intervention, occurring in 81.1% (30/37) of eyes undergoing PKP compared with 34.8% (8/23) of eyes with no PKP (P = 0.0003). CONCLUSIONS: Visual rehabilitation in Peters anomaly remains a challenge, but outcomes can be optimized using a comprehensive clinical management algorithm according to disease severity.

A large deletion spanning PITX2 and PANCR in a Chinese family with Axenfeld-Rieger syndrome.

Purpose: To identify the genetic cause in a four-generation Chinese family with Axenfeld-Rieger syndrome (ARS). Methods: The family members received clinical examinations of the eye, tooth, periumbilical skin, and heart. Sanger sequencing and whole-exome sequencing (WES) were performed to screen potential mutations. The genomic deletion region around the PITX2 gene was estimated from single nucleotide polymorphism (SNP) data from WES and then confirmed with "quantitative PCR (qPCR) using a set of primers. The DNA breakpoint was further identified with long-range PCR and Sanger sequencing. Results: Symptoms including anterior segment dysplasia of the eye (iris dysplasia, multiple pupils, and posterior embryotoxon), dental dysplasia, and periumbilical skin redundancy were present in all of the affected individuals. Three of them had glaucoma. Corneal abnormalities (inferior sclerocornea, corneal endothelial dystrophy, and central corneal scar) were seen in most of the affected individuals. Cataract, limited eye movement, electrocardiographic abnormalities, intellectual disability, and recurrent miscarriages were observed in some of the affected individuals. No mutations in the coding and exon-intron adjacent regions of the PITX2 and FOXC1 genes were identified with Sanger sequencing. According to the SNP data from WES, we suspected that there might be a deletion region (at most 1.6 Mb) around the PITX2 gene. With the use of qPCR and long-range PCR, we identified a 53,840 bp deletion (chr4: 111,535,454-111,588,933) spanning PITX2 and PANCR. The genomic deletion cosegregated with the major ARS symptoms observed in the family members. Conclusions: With the help of WES, qPCR, and long-range PCR, we identified a genomic deletion encompassing PITX2 and the adjacent noncoding gene PANCR in a Chinese family with ARS. The clinical features of the affected individuals are reported. This work may broaden understanding of the phenotypic and mutational spectrums related to ARS.

Assessment of angle closure spectrum disease as a continuum of change using gonioscopy and anterior segment optical coherence tomography.

PURPOSE: Studies examining the anterior chamber angle and angle closure disease often compare quantitative angle information obtained using anterior segment optical coherence tomography (ASOCT) with one of several ordinal scales derived using gonioscopy. We test the assumption that the ordinal gonioscopic angle grades have equal step sizes and can be analysed using metric statistics. METHODS: The medical records of 214 consecutive patients who were referred for assessment of the anterior chamber angle were prospectively examined using gonioscopy and ASOCT (Spectralis Optical Coherence Tomography, OCT, www.heidelbergengineering.com). Anterior chamber angle parameters (angle opening distance, AOD, and trabecular-iris space area, TISA at 500 and 750 microns) were extracted from ASOCT images using a semi-automated segmentation algorithm written on MATLAB (www.mathworks.com). We first matched the quantitative values for each gonioscopic grade (0-4, from no structures visible to ciliary body visible) and described the frequency distributions to determine separability. We then applied a grade-agnostic clustering algorithm to determine the concordance between algorithm-clustered groups (using solely quantitative data) and those obtained using gonioscopy. RESULTS: The frequency distributions of the quantitative ASOCT parameters for each angle grade were mostly non-parametric and displayed unique distribution characteristics, with a floor effect seen for grade 0 and the lack of a ceiling effect seen for grades 3 and 4. Although we found significant differences in quantitative values across the five angle grades using the frequency distributions, some pairwise comparisons were indistinguishable (such as grades 0 and 1, and grades 3 and 4) due to the overlaps in distributions. On average, differences in quantitative values were consistent between gonioscopic grade steps, but there remained substantial variability that confounds prediction of change between ordinal steps. The clustering algorithm showed approximately 10% of cases with the same group assignment as that of the gonioscopic grade, improving slightly to 30% when the top 5% of quantitative data were excluded from analysis. CONCLUSIONS: Our results do not necessarily support the assumption that the ordinal scales used in gonioscopy can be interpreted using an interval scale. We highlight the need for better methods of describing the course and risk of angle closure spectrum disease to identify disease progression and conversion, where gonioscopy remains the gold standard.

Isolation and Characterization of primary human trabecular meshwork cells from segmental flow regions: New tools for understanding segmental flow.

Segmental flow in the human trabecular meshwork is a well-documented phenomenon but in depth mechanistic investigations of high flow (HF) and low flow (LF) regions are restricted due to the small amount of tissue available from a single donor. To address this issue we have generated and characterized multiple paired HF and LF cell strains. Here paired HF and LF cell strains were generated from single donors. Cells were characterized for growth and proliferation, as well as gene and protein expression of potential segmental region markers. Cells isolated from HF and LF regions have similar growth and proliferation rates. Gene expression data reveals vascular cell adhesion protein 1 (VCAM1), thrombospondin 2 (THBS2), and tissue inhibitor of metalloproteinase 1 (TIMP1) are potential markers of LF cells in vitro. Protein expression of VCAM1, THBS2 and TIMP1 are complex and may reflect the dynamic nature of the TM. Initial protein expression levels of these genes is either similar between HF and LF cells (VCAM1, THBS2), or higher in HF compared to LF in some strains (TIMP1). However, after long term culture LF cells express higher levels of VCAM1, TIMP1 and THBS2 protein compared to HF cells. HF and LF cell strains are a powerful new tool that enable understanding segmental flow allowing for multiple experiments on the same genetic background.

Surgical outcomes of Glaucoma associated with Axenfeld-Rieger syndrome.

BACKGROUND: The surgical management of glaucoma associated with Axenfeld-Rieger Syndrome (ARS) is poorly described in the literature. The goal of this study is to compare the effectiveness of various glaucoma surgeries on intraocular pressure (IOP) management in ARS. METHODS: Retrospective cohort study at a university hospital-based practice of patients diagnosed with ARS between 1973 and 2018. Exclusion criterion was follow-up less than 1 year. The number of eyes with glaucoma (IOP ≥ 21 mmHg with corneal edema, Haabs striae, optic nerve cupping or buphthalmos) requiring surgery was determined. The success and survival rates of goniotomy, trabeculotomy±trabeculectomy (no antifibrotics), cycloablation, trabeculectomy with anti-fibrotics, and glaucoma drainage device placement were assessed. Success was defined as IOP of 5-20 mmHg and no additional IOP-lowering surgery or visually devastating complications. Kaplan-Meier survival curves and the Wilcoxon test were used for statistical analysis. RESULTS: In 32 patients identified with ARS (median age at presentation 6.9 years, 0-58.7 years; median follow-up 5.4 years, 1.1-43.7 years), 23 (71.9%) patients were diagnosed with glaucoma at median age 6.3 years (0-57.9 years). In glaucomatous eyes (46 eyes), mean IOP at presentation was 21.8 ± 9.3 mmHg (median 20 mmHg, 4-45 mmHg) on 1.0 ± 1.6 glaucoma medications. Thirty-one eyes of 18 patients required glaucoma surgery with 2.2 ± 1.2 IOP-lowering surgeries per eye. Goniotomy (6 eyes) showed 43% success with 4.3 ± 3.9 years of IOP control. Trabeculotomy±trabeculectomy (6 eyes) had 17% success rate with 14.8 ± 12.7 years of IOP control. Trabeculectomy with anti-fibrotics (14 eyes) showed 57% success with 16.5 ± 13.5 years of IOP control. Ahmed© (FP7 or FP8) valve placement (8 eyes) had 25% success rate with 1.7 ± 1.9 years of IOP control. Baerveldt© (250 or 350) device placement (8 eyes) showed 70% success with 1.9 ± 2.3 years of IOP control. Cycloablation (4 eyes) had 33% success rate with 2.7 ± 3.5 years of IOP control. At final follow-up, mean IOP (12.6 ± 3.8 mmHg, median 11.8 mmHg, 7-19 mmHg) in glaucomatous eyes was significantly decreased (p < 0.0001), but there was no difference in number of glaucoma medications (1.6 ± 1.5, p = 0.1). CONCLUSIONS: In our series, greater than 70% of patients with ARS have secondary glaucoma that often requires multiple surgeries. Trabeculectomy with anti-fibrotics and Baerveldt glaucoma drainage devices showed the greatest success in obtaining IOP control.

The diagnosis and phacoemulsification in combination with intraocular lens implantation for an Axenfeld-Rieger syndrome patient with small cornea: a case report.

BACKGROUND: Axenfeld-Rieger syndrome (ARS) is a congenital disease with a series of developmental abnormalities, and no case of ARS with cataract and small cornea has been reported in previous studies. In the present report, we aimed to describe the diagnosis and phacoemulsification of an ARS patient with small cornea. CASE PRESENTATION: A 58-year-old Han Chinese male patient who was referred to Eye Center of the Second Affiliated Hospital of Zhejiang University Medical College was diagnosed with ARS. Systemic and ophthalmic examination and genetic testing were performed. The slit-lamp microscopic examination of anterior segment showed obvious nuclear cataract, iris lesions, and the abnormal cornea of both eyes with small transversal and longitudinal diameters. ARS with bilateral complicated cataract and small cornea was diagnosed. Microincision-phacoemulsification in combination with intraocular lens implantation was performed on his left eye. After successful surgery of his left eye, the best-corrected visual acuity (BCVA) was obviously improved from 2 to 0.5 (LogMAR). A transient elevation of intraocular pressure (IOP) was controlled with medication. CONCLUSIONS: Through genetic testing, a known pathogenic mutation NM_153427.2:c.272G > A was detected on the PITX2 gene; and an unknown mutation NM_001453.2:c.1063C > T was detected on FOXC1 gene. For the ARS patient with complicated cataract, the visual acuity was increased by phacoemulsificasion in combination with microincision.

Axenfeld-Rieger Anomaly and Neuropsychiatric Problems-More than Meets the Eye.

OBJECTIVE: The main purpose of this article is to demonstrate the co-occurrence of Axenfeld-Rieger anomaly and neuropsychiatric problems as clinical signs of genetically determined cerebral small vessel disease in two patients. CASE STUDY: We report on two adolescent individuals with ocular anterior segment dysgenesis (Axenfeld-Rieger anomaly) presenting with neuropsychiatric symptoms. Both patients underwent cerebral magnetic resonance imaging showing white matter T2-hyperintensities involving different brain regions, suspective of cerebral small vessel disease. Genetic analysis revealed pathogenic mutations in the FOXC1 gene (patient 1) and the COL4A1 gene (patient 2), respectively. CONCLUSION: We report on the co-occurrence of ocular anterior segment dysgenesis (Axenfeld-Rieger anomaly) and neuropsychiatric symptoms as clinical signs of genetically determined cerebral small vessel disease in two patients. In both patients, the cerebral lesions involved the frontotemporal regions, brain regions that control social behavior as well as executive and cognitive function, highlighting the fact that neuropsychiatric symptoms may be early clinical presentations of cerebral small vessel disease. We further provide a review of monogenic causes of pediatric cerebral small vessel disease, emphasizing the links to childhood-onset neuropsychiatric disease.

Changes in angle kappa and angle alpha before and after cataract surgery.

PURPOSE: To observe the distributions and changes in angle kappa and angle alpha preoperatively and postoperatively in patients with cataract who were implanted with a multifocal intraocular lens (mIOL). SETTING: The First Affiliated Hospital of Northwest University, Shaanxi, China. DESIGN: Prospective nonrandomized noncomparative case series. METHODS: Eyes that underwent phacoemulsification were included. The magnitudes and orientations of angle kappa and angle alpha preoperatively and postoperatively were compared, respectively. RESULTS: The study comprised 81 eyes of 70 patients. The magnitude of angle kappa significantly decreased after phacoemulsification. No significant differences were observed between preoperative and postoperative angle kappa in orientation, as well as between preoperative and postoperative angle alpha. The correlations between preoperative and postoperative angle kappa and angle alpha were significant. There were displacement vectors for angle kappa (0.15 ± 0.10) and angle alpha (0.12 ± 0.12) after phacoemulsification. Locations of angle kappa of right and left eyes were scattered mostly in the temporal side of corneal light reflection, whereas locations of angle alpha were well organized in the horizontal position on temporal sides of corneal light reflection. CONCLUSIONS: The distribution of angle alpha was more organized compared with angle kappa. Angle kappa may change after phacoemulsification. During preoperative evaluation for patients with cataract planning for mIOLs implanted angle alpha may be a more reliable and stable factor compared with angle kappa.

Evaluation of the vitreous chamber depth: An assessment of correlation with ocular biometrics.

Purpose: The mechanism of ocular growth eludes us and research on vitreous chamber depth (VCD) is lacking. The purpose of this study was to evaluate the role of VCD and its ratio to axial length (AL) in relation to ocular biometry. Methods: This retrospective study of patients planned for cataract surgery was performed at a tertiary center. Data regarding AL, anterior chamber depth (ACD), lens thickness (LT), and central corneal thickness (CCT) of 640 eyes was noted. Anterior segment (AS) was measured as sum of CCT, ACD, and LT, while VCD was calculated as the difference between AL and AS. Correlation of VCD and VCD: AL with ocular biometry was the primary outcome measure. Three groups were formed on the basis of AL and Pearson correlation coefficient (R) was applied. Results: Mean VCD was 15.38+/-1.14 mm. Mean VCD: AL was 0.66+/-0.02. VCD had a very strong relation with AL (R = 0.9, P < 0.001) only, whereas VCD: AL had a good--strong relation with AL (R = 0.5, P < 0.001), AS (R = 0.7, P < 0.001), ACD (R = 0.3, P < 0.001), and LT (R = 0.5, P < 0.001). The relation of VCD: AL with AS was very strong across all groups (R ≤ -0.8, P < 0.001 in all groups). 85% of eyes in group with AL <22 mm had VCD: AL <0.67, conversely 85% of eyes with AL >24.5 mm had VCD: AL >0.67. Conclusion: : We found VCD to have the strongest relation with AL. VCD: AL was more consistent and showed a strong relation to ocular biometry across all ALs. This suggests the possible utility of the ratio VCD: AL while evaluating ocular growth, refractive status, and myopia-related complications.

Intra-lenticular lens aspiration in paediatric cases with anterior dislocation of lens.

PURPOSE: To assess the outcomes of intra-lenticular lens aspiration (ILLA) in paediatric cases with anterior dislocation of lens. METHODS: A retrospective review of medical records of cases with anterior dislocation of the lens in children (age < 16 years) that underwent ILLA between June 2017 and May 2018 was performed. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), and anterior segment findings were noted at presentation and follow-up. Surgical notes were reviewed for all cases. Post-operative central corneal thickness (CCT) and central macular thickness (CMT) were recorded. RESULTS: Eleven eyes of eight patients with a median age of ten years underwent ILLA. There were four males and four females. The median duration of symptoms was 2 months, CDVA was 1.77 logMAR, and IOP was 16 mm of Hg. Ten eyes had corneo-lenticular touch with corneal oedema, and two had raised IOP at presentation. Homocystinuria (n = 2/8), Microspherophakia (n = 2/8), Marfan syndrome (n = 1/8), Buphthalmos (n = 1/8) and Ectopia lentis et pupillae (n = 1/8) were the identifiable causes for anterior dislocation. There were no intra-operative complications in any case. Immediate post-operative corneal oedema and raised IOP was observed in nine and three cases respectively and was treated with medical therapy. The median post-operative CDVA and IOP at 6-months was 1 logMAR and 15 mm of Hg respectively. The median CCT and CMT were 516 and 248 µm respectively. Five eyes developed a central corneal descemet scar. CONCLUSIONS: ILLA is a safe and effective technique for surgical removal of an anteriorly dislocated lens in paediatric cases.