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Fulltext Exploiting the Generative Adversarial Network Approach to Create a Synthetic Topography Corneal Image

Jameel SK, Aydin S, Ghaeb NH, Majidpour J, Rashid TA, Salih SQ, et al.

Biomolecules, 2022 Dec 16;12(12).
PMID: 36551316 DOI: 10.3390/biom12121888

Corneal diseases are the most common eye disorders. Deep learning techniques are used to perform automated diagnoses of cornea. Deep learning networks require large-scale annotated datasets, which is conceded as a weakness of deep learning. In this work, a method for synthesizing medical images using conditional generative adversarial networks (CGANs), is presented. It also illustrates how produced medical images may be utilized to enrich medical data, improve clinical decisions, and boost the performance of the conventional neural network (CNN) for medical image diagnosis. The study includes using corneal topography captured using a Pentacam device from patients with corneal diseases. The dataset contained 3448 different corneal images. Furthermore, it shows how an unbalanced dataset affects the performance of classifiers, where the data are balanced using the resampling approach. Finally, the results obtained from CNN networks trained on the balanced dataset are compared to those obtained from CNN networks trained on the imbalanced dataset. For performance, the system estimated the diagnosis accuracy, precision, and F1-score metrics. Lastly, some generated images were shown to an expert for evaluation and to see how well experts could identify the type of image and its condition. The expert recognized the image as useful for medical diagnosis and for determining the severity class according to the shape and values, by generating images based on real cases that could be used as new different stages of illness between healthy and unhealthy patients.

Matched MeSH terms: Corneal Diseases*
Primary corneal myxoma

Soong T, Soong V, Salvi SM, Raynor M, Mudhar H, Goel S, et al.

Cornea, 2008 Dec;27(10):1186-8.
PMID: 19034139 DOI: 10.1097/ICO.0b013e31817a5d0b

Primary corneal myxoma is extremely rare. It has only been reported on 2 previous occasions. Secondary corneal myxomas are more common, arising from corneal diseases such as infective keratitis, keratoconus, and bullous keratopathy. Myxomas occur commonly in other soft tissues such as the heart, paranasal sinuses, and muscles but can rarely present in periocular structures including the conjunctiva, orbit, and eyelid. Ours is only the third case of primary corneal myxoma reported in the literature and illustrates several unusual features. These include an inferonasal location between the corneal epithelium and Bowman layer and with no relationship to the corneal stroma, rapid tumor growth over a 3-month period, and no previous ocular trauma or conjunctival pathology. The histology of this lesion has an important part to play in the management of this condition as it determines the cellular origin, establishes a benign or malignant state, and helps with treatment and prognosis. One reported case of primary corneal myxoma recurred within 2 months after local resection. This was treated with bandage soft contact lens, and no recurrence had been reported since. Our case is now 12 months post op and has had no recurrence.

Matched MeSH terms: Corneal Diseases/pathology*; Corneal Diseases/surgery*; Corneal Diseases/ultrasonography
Fulltext Changes in apical corneal curvature in unilateral primary pterygium and normal adults using Simulated-K and corneal irregularity measurement

Mohd Radzi Hilmi, Nur Hidayah Musa, Khairidzan Mohd Kamal, Mohd Zulfaezal Che Azemin, Nur Nabilah Maruziki, Nur Ain Norazmar, et al.

International Journal of Allied Health Sciences, 2019;3(2):588-594.
MyJurnal

This paper aimed to describe variation in apical corneal curvature between unilateral primary pterygium and normal adults utilizing simulated-K and corneal irregularity measurement corneal indices. A total of 100 participants comprise 50 unilateral primary pterygium eyes from 50 patients and 50 normal adults were recruited in this study. Diagnosis and classification of primary pterygium were done by a consultant ophthalmologist (KMK). Standard optometric examinations were performed in all participants. Simulated-K (SimK) and corneal irregularity measurement (CIM) was objectively measured using a corneal topographer. Three measurements based on best image quality for SimK and CIM were taken by single operator in a same visit. Difference for both SimK and CIM parameters between primary pterygium and normal groups were determined via independent T-test. Overall mean and standard deviation (n = 120) of SimK and CIM were found higher in primary pterygium group (9.06 ± 4.49 D and 11.48 ± 3.12) compared to normal (1.63 ± 0.67 D and 0.62 ± 0.24) respectively. Independent T-test results showed significance difference in SimK and CIM values between primary pterygium groups and normal (both P< 0.001). Both SimK and CIM corneal indices can be an important tool in describing and predicting changes on the corneal curvature due to pterygium progression. However, it is worth to note that the detectability of changes in anterior corneal curvature is limited to 5 mm of central corneal curvature.

Matched MeSH terms: Corneal Diseases
Fulltext Topical insulin for healing of diabetic epithelial defects?: A retrospective review of corneal debridement during vitreoretinal surgery in Malaysian patients

Bastion ML, Ling KP

Med J Malaysia, 2013 Jun;68(3):208-16.
PMID: 23749008 MyJurnal

PURPOSE: To investigate whether topical insulin improves healing rate of corneal epithelial erosions induced during vitreoretinal surgery in diabetics.
METHODS: We retrospectively reviewed case notes and serial post-operative photographs of 15 eyes of 14 patients who had corneal epithelial debridement performed during various vitreoretinal surgeries to improve one surgeon's view over a 10 month period in 2010.
RESULTS: Three groups were identified: DTI, comprising diabetics who received topical insulin 1 unit qds postoperatively (n=5); DCT comprising diabetics treated with conventional post-operative medications only (n=5) and NDCT comprising non diabetic patients on conventional post operative therapy (n=5). Only eyes in which the corneal epithelial defect had been serially photographed at time, t= 0, 12, 24, 36, 48, 60, 72 and 120 hours following commencement of topical medications were included. The size of the defect was calculated using local software. DTI eyes had a significantly smaller defect size at t= 24 (p=0.009), 36 (p=0.009), 48 (p=0.015) and 60 hours (p=0.005) compared to DCT eyes and had no statistical difference from NDCT eyes at all times in the Mann Whitney U analysis (p>0.05). In the diabetic operated bilaterally, the insulin treated eye re-epithelialised by 48 hours whereas fellow eye treated conventionally re-epithelialised in 72 hours.
CONCLUSIONS: Topical insulin or insulin eye drops 1 unit qds may be applied to the corneal surface to normalize the rate of healing of epithelial defects in diabetic patients undergoing epithelial debridement to improve the surgeon's view.

Matched MeSH terms: Corneal Diseases/surgery
Fulltext Iatrogenic corneal perforation in Terrien Marginal Degeneration

Mohd Razali K

Med J Malaysia, 2013 Apr;68(2):173-4.
PMID: 23629570 MyJurnal

This case report is about a rare disease with unusual presentation. Failure to recognise atypical presentation may lead to error in managing the patient and cause disastrous complications. Here we highlight a case of Terrien Marginal Degeneration in both eyes with atypical presentation; namely pseudopterygium. A 22 year old man was referred to our centre for iatrogenic right eye corneal perforation after having an atypical pterygium removed at another hospital. On arrival, his vision was 1/60 in both eyes with bilateral cornea Terrien Marginal Degeneration. His right eye anterior chamber was deep with a conjunctival flap covering the perforation site which was located from the 2.30 - 3.30 clock position nasally with no aqueous leak. However after a day his right eye anterior chamber became flat and there was fast aqueous leak from the perforation site. An emergency C shaped peripheral corneal lamellar keratoplasty was performed to seal the perforation. Post operatively his right eye improved to 6/24.

Matched MeSH terms: Corneal Diseases/surgery
A fluid mechanical explanation of the spontaneous reattachment of a previously detached Descemet membrane

Ismail Z, Fitt AD, Please CP

Math Med Biol, 2013 Dec;30(4):339-55.
PMID: 23054933 DOI: 10.1093/imammb/dqs028

Descemet membrane detachment (DMD) is a rare but potentially serious surgical complication that arises most often during cataract surgery. A recent study (Couch, S. M. & Baratz, K. H. (2009) Cornea, 28, 1160-1163) cited the case of a patient with DMDs in both eyes, noting that though one detachment was surgically repaired, the other spontaneously reattached and needed no further treatment. A fluid mechanical model of buoyancy-driven aqueous humour flow in the anterior chamber around a DMD is developed to explain this phenomenon. The analytical model is based on the lubrication theory limit of the Navier-Stokes equations. The flow is determined for a fixed geometry and the possible motion of the DMD is then analysed. Numerical calculations are also carried out (using COMSOL© Multiphysics) to confirm the lubrication theory results. The analytical and numerical results both show that, under the correct conditions, either spontaneous reattachment or worsening of the tear may occur. We conclude that it is possible that clinical outcomes for DMDs may be controlled by adjusting the temperature difference across the eye and/or the orientation of the patient.

Matched MeSH terms: Corneal Diseases/physiopathology*
Fulltext Bilateral corneal perforation in a sexually active adult male with gonococcal conjunctivitis

Bastion ML, Prakash K, Siow YC, Loh SS

Med J Malaysia, 2006 Aug;61(3):366-8.
PMID: 17240593 MyJurnal

A 41 year-old Malay man had been treated by general practitioners for bilateral red eyes with profuse discharge of three weeks' duration with no improvement. He then presented to an ophthalmologist who noted profuse purulent discharge, bilateral corneal perforation, lid swelling and chemosis. Culture of the ocular discharge grew Neisseria gonorrhoeae. Treatment with systemic and topical antibiotics prevented microperforations in the right eye from progressing to overt perforation and was able to control disease in the left eye.

Matched MeSH terms: Corneal Diseases/etiology*
Study of the factors associated with the presence of white dots in the corneas of regular soft contact lens users from an Asian country

Bastion ML, Mohamad MH

Eye Contact Lens, 2006 Sep;32(5):223-7.
PMID: 16974154

PURPOSE: To investigate factors associated with the presence of microdot deposits or white dots (WDs) on confocal microscopy in regular soft contact lens (SCL) users.
METHODS: This cross-sectional observational study investigated changes in the cornea in regular SCL users by using an in vivo slit-scanning microscope (ConfoScan 3). Images were analyzed by noting the presence of highly reflective WDs. Factors associated with WDs were analyzed by using an unpaired t test with Welch correction.
RESULTS: There were 56 SCL wearers. Of these, a group of 10 had WDs (GWD) in various parts of the cornea. They had worn SCLs for 7 to 20 years and had a mean total duration of SCL wear of 13.6 +/- 4.4 years. Their mean age was 35.8 +/- 10.4 years. They were compared with a group of SCL wearers with no evidence of WDs (GNWD). The mean age of GNWD was 29.1 +/- 7.2 years, with a mean duration of SCL use of 8.17 +/- 5.1 years. The two groups were compared in terms of age, total duration of SCL wear (years), duration in hours per week, SCL water content (%), mean cell density in the endothelium and stroma, endothelial cell coefficient of cell size variation, and percentage of hexagonal cells. Only the duration of SCL wear was significantly associated with the presence of WDs (p=0.0042). WDs were most commonly found in the posterior stroma (n = 9). Two patients had WDs in the epithelium, with one of these having WDs in the endothelium. All patients except one with a hazy left eye scan had WDs bilaterally and symmetrically.
CONCLUSIONS: Confocal microscopy allows visualization of WDs in the corneas of Asian regular SCL users. Patients with WDs have a longer history of SCL wear. WDs may represent an early stage of corneal disease or degeneration associated with alterations in cell behavior.

Matched MeSH terms: Corneal Diseases/diagnosis; Corneal Diseases/etiology*; Corneal Diseases/epidemiology
Fulltext Crystal deposits in cornea from the use of vitamin C eye drops

Choong YY, Arumugam G

Med J Malaysia, 1999 Dec;54(4):526-7.
PMID: 11072476

There are a number of differential diagnoses for crystal deposits in the cornea. With the presence of a corneal epithelial defect, the differential diagnosis can be narrowed down to either infective causes or deposits from topical medications. This report describes a case of crystal deposits in the cornea from the use of Vitamin C eye drops.

Matched MeSH terms: Corneal Diseases/chemically induced*; Corneal Diseases/etiology; Corneal Diseases/pathology
Human umbilical cord-mesenchymal stem cells: a promising strategy for corneal epithelial regeneration

Azmi SM, Salih M, Abdelrazeg S, Roslan FF, Mohamed R, Tan JJ, et al.

Regen Med, 2020 03;15(3):1381-1397.
PMID: 32253974 DOI: 10.2217/rme-2019-0103

Aim: As a strategy to improve the outcome of ex vivo cultivated corneal epithelial transplantation, the role of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) is investigated in promoting corneal epithelial growth and functions. Materials & methods: Human telomerase-immortalized corneal epithelial cells were characterized and its functions evaluated by scratch migration assay, cellular senescence, HLA expression and spheres formation with hUC-MSC. Results: Expression of corneal epithelial markers was influenced by the duration and method of co-culture. Indirect co-culture improved cellular migration and delayed senescence when treated after 3 and 5 days. hUC-MSC downregulated expression of HLA Class I and II in IFN-γ-stimulated human telomerase-immortalized corneal epithelial cells. Conclusion: hUC-MSC promote corneal epithelial growth and functions after treatment with hUC-MSC.

Matched MeSH terms: Corneal Diseases/metabolism; Corneal Diseases/pathology; Corneal Diseases/therapy*
Diabetes and pachymetry changes in pregnancy

Santiagu F, Bakhtiari A, Iqbal T, Khaliddin N, Lansingh VC, Subrayan V

Int Ophthalmol, 2018 Oct;38(5):2069-2076.
PMID: 28879527 DOI: 10.1007/s10792-017-0701-5

BACKGROUND: Purpose of this study is to evaluate changes in the central corneal thickness (CCT) in patients during the third trimester and postpartum phases of normal pregnancy, pregestational diabetes mellitus (DM), and gestational diabetes mellitus (GDM).
METHODS: This was a prospective study. Patients that fulfilled the inclusion criteria were recruited from the obstetric clinic. They were grouped into normal pregnancy, pregestational DM, and GDM. Ophthalmic assessment and haematological investigations were done during the third trimester (after 28 weeks of gestation) and in the postpartum phase (6 weeks postpartum).
RESULTS: A total of 192 pregnant patients were recruited for this study. Out of the 192 patients, only 143 of them came back for their follow-up 6 weeks postpartum. A total of 70 (36.5%) normal pregnancy patients, 51 (26.6%) DM patients, and 71 (36.9%) GDM patients were included in this prospective study. Our study showed that the CCT decreased postpartum in all three groups. Patients in all three groups did not have significantly different CCT during the third trimester of pregnancy and postpartum phase. However, patients who had thicker CCT irrespective of the grouping during the third trimester also had a thicker CCT post-delivery (p value <0.001). However, these changes did not appear to affect refractive error and visual acuity.
CONCLUSIONS: Diabetes mellitus during pregnancy did not appear to influence the CCT.
Study site: Obstetrics clinic, University Malaya Medical Center (UMMC), Kuala Lumpur, Malaysia

Matched MeSH terms: Corneal Diseases/diagnosis*; Corneal Diseases/etiology; Corneal Diseases/physiopathology
Corneal Hysteresis Is Reduced in Obstructive Sleep Apnea Syndrome

Nadarajah S, Samsudin A, Ramli N, Tan CT, Mimiwati Z

Optom Vis Sci, 2017 10;94(10):981-985.
PMID: 28858045 DOI: 10.1097/OPX.0000000000001117

SIGNIFICANCE: To our knowledge, this is the first time a study looking at the association between corneal hysteresis (CH) and obstructive sleep apnea syndrome (OSAS) severity has been reported. We provide evidence that CH is lower in OSAS and speculate on the possible causes.
PURPOSE: The present study aims to look at the association between CH and severity of OSAS, and whether CH could be another link between OSAS and the development of glaucoma.
METHODS: This was a cross-sectional, observational study at the University Malaya Medical Centre, Kuala Lumpur. Patients undergoing polysomnography for assessment of OSAS were recruited. We measured central corneal thickness (CCT) using optical biometry, and CH using ocular response analysis. Intraocular pressure (IOP) and Humphrey visual field (HVF) indices were also measured. The Apnea Hypopnea Index (AHI) divided patients into normal, mild, moderate, and severe OSAS categories. The normal and mild categories (47.9%) were then collectively called group 1, and the moderate and severe categories (52.1%) were called group 2. T tests, Pearson correlation tests, and general linear model analysis were performed, with P .05). CH correlated negatively with AHI (r = -0.229, P = .013) and positively with lowest oxygen saturation (r = 0.213, P = .022).
CONCLUSIONS: CH is lower in moderate/severe OSAS than in normal/mild cases. This may be another link between OSAS and the development of glaucoma; further studies are indicated to determine the significance of this connection.

Matched MeSH terms: Corneal Diseases/diagnosis; Corneal Diseases/etiology*; Corneal Diseases/physiopathology
Analysis of pterygium size and induced corneal astigmatism

Mohammad-Salih PA, Sharif AF

Cornea, 2008 May;27(4):434-8.
PMID: 18434847 DOI: 10.1097/ICO.0b013e3181656448

To study the relationship between pterygium size (extension, width, total area) and corneal astigmatism in eyes with unilateral primary pterygium. Also to determine the critical size for surgery before the occurrence of a significant corneal astigmatism.

Matched MeSH terms: Corneal Diseases/diagnosis; Corneal Diseases/etiology*
Fulltext Determinants of posterior corneal biometric measurements in a multi-ethnic Asian population

Ang M, Chong W, Huang H, Wong TY, He MG, Aung T, et al.

PLoS One, 2014;9(7):e101483.
PMID: 25006679 DOI: 10.1371/journal.pone.0101483

To describe the corneal and anterior segment determinants of posterior corneal arc length (PCAL) and posterior corneal curvature (PCC).

Matched MeSH terms: Corneal Diseases/diagnosis*; Corneal Diseases/surgery
Fulltext Effects of edible bird's nest (EBN) on cultured rabbit corneal keratocytes

Zainal Abidin F, Hui CK, Luan NS, Mohd Ramli ES, Hun LT, Abd Ghafar N

BMC Complement Altern Med, 2011;11:94.
PMID: 21992551 DOI: 10.1186/1472-6882-11-94

There has been no effective treatment or agent that is available for corneal injury in promoting corneal wound healing. Previous studies on edible bird's nest extract (EBN) had reported the presence of hormone-like substance; avian epidermal growth factor that could stimulate cell division and enhance regeneration. This study aimed to investigate the effects of EBN on corneal keratocytes proliferative capacity and phenotypical changes.

Matched MeSH terms: Corneal Diseases/drug therapy*; Corneal Diseases/physiopathology
Fulltext Osteo-odonto-keratoprosthesis for end-stage cornea blindness

Wong HS, Then KY, Ramli R

Med J Malaysia, 2011 Oct;66(4):369-70.
PMID: 22299563 MyJurnal

We report the first case of Osteo-odonto-keratoprosthesis (OOKP) who successfully underwent surgery in Malaysia following a grade 4 (severe) chemical injury in both eyes in 2006. The patient's left eye was eviscerated and his right eye underwent penetrating keratoplasty. However, the corneal graft failed and became opaque. His right eye could only perceive light. The OOKP was offered to him hoping to recover some functional vision. He underwent a 2-stage surgery to implant the OOKP into his right eye. However, 2 months post-operation, he developed vitreous haemorrhage. A successful pars plana vitrectomy (PPV) was performed via the limited view through the lens. He attained a final visual acuity of 6/60 (N36). He was able to mobilize more independently, feed, dress himself and read large print.

Matched MeSH terms: Corneal Diseases/surgery*
Ex vivo growth of rabbit bulbar, fornix and palpebral conjunctival epithelia in a serum-free and feeder layer-free culture system

Nizam MH, Ruszymah BH, Chua KH, Ghafar NA, Hamzah JC

Med J Malaysia, 2008 Jul;63 Suppl A:111-2.
PMID: 19025010

This study was conducted to explore the feasibility of culturing conjunctiva epithelial cells in serum-free and feeder layer-free culture system with regard to the cell morphology and immunocytochemistry of the rabbit bulbar, fornix and palpebral conjunctiva epithelia. The results showed that epithelium cells from all the three conjunctiva regions can be cultured in a serum-free and feeder layer-free environment. We obtained highest epithelial growth from fornix region with minimum invasion of fibroblast cells compared to other area. All cultured cells were stained positive for cytokeratin 19 and MUC5AC and negative for cytokeratin 3. These findings suggested that fornix was a better source of cells for the development of tissue engineered conjunctiva for future clinical application.

Matched MeSH terms: Corneal Diseases/surgery*
Scanning electron microscopy of cornea re-epithelization after transplanted with bilayered corneal construct

Masrudin SS, Ghafar NA, Saidi M, Aminuddin BS, Rahmat A, Ruszymah BH, et al.

Med J Malaysia, 2008 Jul;63 Suppl A:109-10.
PMID: 19025009

The present work was to determine the development and re-epithelization of bilayered corneal construct (BCC) in vitro and in vivo using scanning electron microscopy (SEM). The in vitro BCC was transplanted to the rabbit's eye and after 90 days the BCC was harvested and analyzed. The corneas were processed for morphology studies. The result indicates that the BICC that was transplanted for 90 days showed good development and re-epithelization of epithelial layer similar to the normal cornea.

Matched MeSH terms: Corneal Diseases/surgery*
Current progress and challenges in ocular surface reconstruction using cultivated epithelial sheet transplantation

Inatomi T, Nakamura T, Koizumi N, Sotozono C, Kinoshita S

Med J Malaysia, 2008 Jul;63 Suppl A:42.
PMID: 19024975

The cultivated epithelial transplantation is a new surgical modality for treating a variety of severe ocular surface disorders. This type of tissue-engineered epithelial sheet provides a rapid epithelial coverage on the corneal surface that reduces inflammation and postoperative complications. Although cultivated corneal epithelial transplantation is an effective surgical strategy, autologous transplantation is limited to unilateral cases. Autologous cultivated oral mucosal epithelial transplantation (COMET) enables surgeons to reconstruct the ocular surface using autologous, non-ocular surface cells, and has opened a new pathway for treating severe, bilateral ocular surface disorders.

Matched MeSH terms: Corneal Diseases/pathology; Corneal Diseases/surgery*
Randomized Controlled Trial of Topical Insulin for Healing Corneal Epithelial Defects Induced During Vitreoretinal Surgery in Diabetics

Fai S, Ahem A, Mustapha M, Mohd Noh UK, Bastion MC

Asia Pac J Ophthalmol (Phila), 2017;6(5):418-424.
PMID: 28828764 DOI: 10.22608/APO.201780

PURPOSE: To determine the effect of topical insulin of 3 concentrations [0.5, 1, and 2 units per drop 4 times per day (QID)] on postoperative corneal epithelial wound healing in diabetic patients.
DESIGN: A double blind randomized controlled hospital-based study involving diabetic patients with postoperative corneal epithelial defect after vitreoretinal surgery.
METHODS: Diabetic patients were randomized to 3 different concentrations of topical insulin (DTI 0.5, DTI 1, and DTI 2) or placebo in the control group (DNS). Primary outcome measure was the rate of corneal epithelial wound healing (mm² per hour) over pre-set interval and time from baseline to minimum size of epithelial defect on fluorescein stained anterior segment digital camera photography. Secondary outcome measure was any adverse effect of topical insulin. Follow-up was 1 month.
RESULTS: Thirty-two eyes of 32 patients undergoing intraoperative corneal debridement with resultant epithelial defect (8 eyes per group) were analyzed. DTI 0.5 was superior to other concentrations achieving 100% healing rate within 72 hours of treatment compared with 62.5% in DNS, 75% in DTI 1, and 62.5% in DTI 2. Statistically, DTI 0.5 achieved significant results (P = 0.036) compared with the diabetic control group (DNS) in terms of mean rate of corneal epithelial wound healing from maximum to minimum defect size. No adverse effect of topical insulin was reported.
CONCLUSIONS: Topical insulin 0.5 units QID is most effective for healing corneal epithelial defect in diabetic patients after vitrectomy surgery compared with placebo and higher concentrations. Topical insulin is safe for human ocular usage.

Matched MeSH terms: Corneal Diseases/drug therapy*; Corneal Diseases/etiology

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