Evaluation of Corneal Curvature and Astigmatism in Patients with Persistent Pupillary Membrane by Partial Coherence Interferometry Measurements

Surgical approach to and morphology of visually significant persistent pupillary membranes

PURPOSE

To characterize the morphology of persistent pupillary membranes (PPMs) in pediatric patients and explore the corresponding surgical approaches.

SETTING

Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China.

DESIGN

Prospective observational study.

METHODS

Consecutive pediatric patients with PPMs who underwent surgery from April 2020 to July 2022 were included. PPM morphology was assessed and categorized according to its anatomic relationship with crystalline lens and distribution of iris strands. The surgical approaches for different morphologies of PPMs were described in detail. The visual outcome and operation-related complications were recorded.

RESULTS

31 eyes from 19 patients were included with the mean age of 7.2 years. 3 morphological variants of PPMs were observed: type I (51.6%, 16/31), a spider-like appearance and no adhesion to the anterior lens capsule (ALC); type II (38.7%, 12/31), a loose central adherence to the ALC and partially thick iris strands attached to the iris collarette; type III (9.7%, 3/31), a tight central adherence to the ALC and only silk-like iris strands. Surgeries were performed with a natural pupil size in type I, while dilated pupil in the other types. The adhesions between PPM and the ALC were separated by viscoelastic injection in type II and by discission needles in type III. The corrected distance visual acuity was significantly improved from 0.34 ± 0.18 logMAR preoperatively to 0.17 ± 0.09 logMAR postoperatively ( P < .001). No operation-related complications were observed during 9.5-month follow-up.

CONCLUSIONS

PPMs were categorized into 3 types according to their different morphologies, which helped to determine the best surgical strategy.

A Study Linking Axial Length, Corneal Curvature, and Eye Axis With Demographic Characteristics in the Emmetropic Eyes of Bangladeshi People

Background Axial length (AL) and corneal curvature (CC) are one of the furthest critical parameters for optometry and oculoplastic surgery. These two variables are crucial in biometry for accurately measuring the power of the intraocular lens in cataract surgery. This research aimed to determine the association linking axial length and corneal curvature with demographic characteristics in emmetropic eyes of Bangladeshi people. Methods This descriptive cross-sectional research was carried out among 200 emmetropic eyes of Bangladeshi people attending the Department of Ophthalmology at Rajshahi Medical College, Bangladesh, with different eye conditions, between July 2017 and June 2018. Data was gathered by conducting person-to-person interviews, checking visual activity using the Snellen chart, and measuring corneal curvature using an auto-keratometer and axial eyeball length using A-scan ultrasonography. Results A total of 200 attendances were studied, 90 males and 110 females. All were emmetropic. The age range was 21-52 years, and the highest contributors were in the 21-30-year age group. The association between right axial length and right corneal curvature shows a negative relation among both sexes. It was -0.61 (β-coefficient (β-coff)), and highly significant in females at -0.89 (β-coff). Additionally, the association between left axial length and left corneal curvature shows a negative relation of -0.65 (β-coff), which was again highly significant in females at -0.87 (β-coff). Both were not significant in males. There was no significant association linking axial length and eye axis in both sexes. The multivariate regression model was used to assess the p-value, and the regression model was adjusted by age. Conclusion Optical parametric measurement is a noninvasive diagnostic and assessment tool that might help in the actual measurement of intraocular lens implantation in cataract surgery and may also provide supplementary information to the researcher domain.

Long term surgical outcome for persistent pupillary membranes with associated ocular abnormalities: a retrospective case series study

BACKGROUND

Deprivation amblyopia is a great concern in hyperplastic persistent pupillary membranes (PPM) which blocked visual axis. Other ocular abnormality may accompany and further hinder the visual development of the infants. We evaluate the long-term visual prognosis and complications in patients with dense PPM and other associated abnormalities treated with early surgical intervention and timely visual rehabilitation.

METHODS

Medical records of patients with surgical removal of PPM from 2000 to 2020 and also receiving visual rehabilitation were retrospectively reviewed. Besides visual axis blocked PPM, patients combined with other amblyopic risk factors or ocular abnormalities were included. Due to preparation for subsequent lens extraction if an underlying cataract was present, the surgical settings including the instruments and wound direction were similar to cataract surgery. All patients were enrolled in a visual rehabilitation program as soon as possible. The results including sex, age, timing of operation, initial and final visual acuity, refractive errors, and complications were recorded.

RESULTS

Seven cases of five patients were included in this case series. Mean age at surgery was 42.3 ± 21.1 months (range, 5 to 66 months) and the post-operative follow-up period was 4.9 years (range, 1.2 to 8.2 years). The patient age at time of surgery ranged from 2.5 months to 2.5 years (mean, 14 months). Mean postoperative follow-up was 5.3 years (range, 2.5-8 years). There were no intra-operative and post-operative complications. Final BCVA varied with a mean value of 0.29 logMAR (range, 0 to 1 logMAR). An associated ocular abnormality of ametropia and strabismus led to the best visual prognosis.

CONCLUSIONS

In patients with PPM, there were no significant complications in any patient using our technique. The surgical settings are easier to handle and more familiar with pediatric surgeons. Besides deprivation with patching, early PPM intervention and timely visual rehabilitation achieve the best visual prognosis in patients associated with risk of ametropic and strabismic amblyopia.

TRIAL REGISTRATION

This retrospective, interventional case series study was conducted at China Medical University Hospital between April 1, 2000 and April 31, 2020. (IRB number: CMUH109-REC2-069 ).