Does the Difference in Axial Length Affect the Refractive Outcome?

Background

The purpose of this study is to compare axial length (AL) and the refractive outcome after phacoemulsification surgery from 2014 to 2019 at Hospital Sultanah Nur Zahirah, Terengganu, Malaysia.

Method

This was a retrospective record review of all cataract patients who met the inclusion criteria and underwent uneventful superior wound phacoemulsification with nontoric intraocular lens (IOL) by a single surgeon from 2014 to 2019. Using optical biometry or immersion technique, the preoperative AL determined solely via the Sanders, Retzlaff and Kraff 2 (SRK2) formula was selected. The postoperative spherical equivalent (SE) at 6 weeks-12 weeks was retrieved. Using Statistical Package for the Social Sciences version 24.0, the mean differences between targeted and actual postoperative SE were analysed based on the AL.

Result

In this study, 490 eyes of 472 patients aged 25 years old-88 years old (mean age 65.72 years old [SD 8.83]) were involved. There were 162 eyes (33%) in Group A (< 23 mm), 189 eyes (39%) in Group B (23.01 mm-24.0 mm) and 139 eyes (28%) in Group C (> 24.0 mm). The mean AL was 23.63 mm (SD 1.19). The mean differences between the targeted and actual postoperative SE were: -0.09 D (SD 0.60) in Group A, -0.07 D (SD 0.53) in Group B and -0.16 D (SD 0.52) in Group C. No significant difference was found between these groups (P = 0.327).

Conclusion

There was no significant difference in the refractive outcome using the SRK2 formula in different ALs after phacoemulsification surgery. Hence, there is no reason to modify or adjust the targeted SE based on AL.

Analysis of the Effectiveness of Metaheuristic Methods on Bayesian Optimization in the Classification of Visual Field Defects

Bayesian optimization (BO) is commonly used to optimize the hyperparameters of transfer learning models to improve the model's performance significantly. In BO, the acquisition functions direct the hyperparameter space exploration during the optimization. However, the computational cost of evaluating the acquisition function and updating the surrogate model can become prohibitively expensive due to increasing dimensionality, making it more challenging to achieve the global optimum, particularly in image classification tasks. Therefore, this study investigates and analyses the effect of incorporating metaheuristic methods into BO to improve the performance of acquisition functions in transfer learning. By incorporating four different metaheuristic methods, namely Particle Swarm Optimization (PSO), Artificial Bee Colony (ABC) Optimization, Harris Hawks Optimization, and Sailfish Optimization (SFO), the performance of acquisition function, Expected Improvement (EI), was observed in the VGGNet models for visual field defect multi-class classification. Other than EI, comparative observations were also conducted using different acquisition functions, such as Probability Improvement (PI), Upper Confidence Bound (UCB), and Lower Confidence Bound (LCB). The analysis demonstrates that SFO significantly enhanced BO optimization by increasing mean accuracy by 9.6% for VGG-16 and 27.54% for VGG-19. As a result, the best validation accuracy obtained for VGG-16 and VGG-19 is 98.6% and 98.34%, respectively.

Comparing the Effectiveness and Adherence between Fixed and Non-Fixed Dorzolamide/Timolol Maleate in Open-Angle Glaucoma Patients in Hospital Universiti Sains Malaysia

Introduction

Glaucoma is an irreversible chronic eye disease in which intraocular pressure (IOP) control is important. This study aimed to assess the IOP-lowering effects and adherence scores between fixed combination dorzolamide/timolol maleate (FCDT) and non-fixed combination dorzolamide and timolol XE (NFDT) in open-angle glaucoma (OAG) patients.

Methods

A randomised controlled trial in a parallel, single-blinded study involving 60 OAG patients was conducted. The patients were randomised into FCDT or NFDT based on a block randomisation technique. A pre-study run-in with Gutt timolol was administered for two weeks. IOP was assessed at baseline, month 1 and month 3, with a bottle weight measurement at month 3.

Results

Only 55 OAG patients were analysed, with 8.4% dropping out. A statistically significant mean IOP reduction was observed in each group from baseline to month 1 (FCDT: mean difference [MD] = 4.93, 95% confidence interval [CI] = 4.00, 5.86); NFDT: MD = 4.92, 95% CI = 4.024, 5.82) and from baseline to month 3 (FCDT: MD 5.17, 95% CI = 4.19, 6.15; NFDT: MD = 4.85, 95% CI = 3.874, 5.82). The overall FCDT mean IOP was significantly lower by 1.02 mmHg (95% CI = -2.01, -0.02) than NFDT (F(1, 53) = 4.19; P = 0.046). A significant interaction was observed between time and treatment at month 3, with the mean IOP for FCDT being lower by 1.22 mg than for NFDT (P = 0.037). The mean adherence score was significantly higher in the FCDT group than in the NFDT group (t stat (df) = 3.88 (53); P < 0.001). The reduction in IOP between the groups became non-significant after adherence was adjusted (F(1, 52) = 2.45; P = 0.124).

Conclusion

Both drugs showed a decrease in IOP but more so in FCDT. However, no difference was found in terms of medication adherence. An emphasis on treatment compliance is needed.

Evaluation of Anatomical and Functional Outcome of Epiretinal Membrane Surgery in Idiopathic Epiretinal Membrane Patients

Objective To evaluate the anatomical and functional outcomes of an idiopathic epiretinal membrane (ERM) between the observation group and intervention group at six months postoperative. Design Prospective cohort study. Participants Patients who met the clinical diagnosis of idiopathic ERM in the age frame of 18-80 years; patients with reduced visual acuity (VA), with best corrected VA of 0.2 LogMar or worse, with symptoms of significant metamorphopsia, who visited our center from June 2021 to June 2022. Methods All idiopathic ERM patients who fulfilled the inclusion criteria were selected. The data recorded included the year of ERM diagnosis, duration of symptoms, age at diagnosis, gender, ethnicity, and presence of other ocular pathologies. Corrected VA, lens status, ERM configuration, and central subfield mean thickness (CST) in spectral domain-optical coherence tomography (SD-OCT), ellipsoid zone integrity (EZ), and disorganized retinal inner layer (DRIL) were recorded for all patients at diagnosis, as well as 3 and 6 months after diagnosis for non-operated patients. For patients who underwent surgery (pars plana vitrectomy (PPV), internal limiting membrane (ILM), and ERM peel), data were recorded similarly with additional data on the type of surgery (vitrectomy or combined phaco vitrectomy) and the development of intra or post-surgical complications. Patients receive information on the symptoms associated with ERM, treatment options, and disease progression. After counseling, the patient makes informed consent to the treatment plan. Patients are seen in the 3rd and 6th month from diagnosis. Combined phaco vitrectomy is performed if there is also significant lens opacity. Main outcome measures VA, CST, EZ, and DRIL at diagnosis and 6 months. Results Sixty subjects (30 interventional and 30 observational arms) were recruited for this study. The mean age in the intervention and observation groups was 62.70 and 64.10 years, respectively. Most ERM patients were female in the intervention group compared to males with 55.2% and 45.2% respectively. The mean pre-op CST was 410.03 μm in the intervention group compared to the pre-op CST 357.13 μm observation group. There were significantly different among groups in pre-op CST (p=0.009) using the independent T-test. Furthermore, the mean difference and 95% confidence interval in post-op CST were -69.67 (-99.17, -40.17). There were significant differences among groups in post-op CST (p<0.001) using the independent T-test. Meanwhile, there is no significant association of DRIL between both groups (p=0.23), with 95% CI of mean difference (-0.13, -0.01) using repeated measure analysis of variance (ANOVA) test. There was a significant association of EZ integrity between groups (p=<0.001), 95% CI of mean difference: (-0.13, -0.01) using a repeated measure ANOVA test. Furthermore, the mean post-op VA between pre and post-op VA was significantly different (p<0.001), with a 95% CI of mean difference (-0.85, -0.28). Finally, there is a significant factor association between the duration of ERM and post-op VA (b=.023, 95% CI .001, .05, p<0.05) with our patients. Conclusion ERM surgery has shown positive outcomes on anatomical and functional aspects with minimal safety-related risks. It is evident that a longer duration of ERM does give a minimal impact on the outcome. SD-OCT biomarkers, such as CST, EZ, and DRIL, can be used as reliable prognosticators in decision-making for surgical intervention.

Lockdown: The Impact on Management of Glaucoma in a Suburban Tertiary Centre in Malaysia

INTRODUCTION

The COVID-19 pandemic brought the world to a standstill in 2020. Many countries have imposed lockdowns, known as the movement-control order (MCO) in Malaysia, to prevent transmission of the disease.

AIM

The objective of this study is to evaluate the impact of the MCO on the management of glaucoma patients in a suburban tertiary hospital.

METHODOLOGY

We conducted a cross-sectional study of 194 glaucoma patients between June 2020 and August 2020 in the glaucoma clinic at Hospital Universiti Sains Malaysia. We evaluated the patients' treatment, visual acuity, intraocular pressure (IOP) measurements, and potential signs of progression. We compared the results with those of their last clinic visits prior to the MCO.

RESULTS

We studied 94 (48.5%) male and 100 (51.5%) female glaucoma patients with a mean age of 65 ± 13.7. The mean duration between pre-MCO and post-MCO follow-up was 26.4 ± 6.7 weeks. There was a significant increase in the number of patients with deterioration of visual acuity, and one patient lost his vision after the MCO. There was also a significant elevation of the mean IOP of the right eye: pre-MCO, 16.7 ± 7.8 mmHg, compared to post-MCO, 17.7 ± 8.8 mmHg (p = 0.027). The cup-to-disc ratio (CDR) for the right eye increased significantly from pre-MCO, 0.72 ± 0.18, to 0.74 ± 0.19 post-MCO (p < 0.001). However, there were no significant changes in IOP or CDR in the left eye. Twenty-four patients (12.4%) missed medications during the MCO period, and 35 patients (18%) required additional topical medications due to the progression of the disease. Only one patient (0.5%) required admission due to uncontrolled IOP.

CONCLUSION

Lockdown, as a preventive step in the COVID-19 pandemic, indirectly caused the progression of glaucoma and uncontrolled IOP.

Infectious Sclerouveitis in an Immunocompetent Patient: A Probable Case of Simultaneous Ocular Tuberculosis and Toxoplasmosis

Simultaneous infections of tuberculosis and toxoplasmosis are uncommon in immunocompetent patients. We report a case of a 30-year-old male who presented with right eye redness and blurring of vision for one month. The visual acuities were hand movement and Snellen 20/30 in the right and left eyes, respectively. Panuveitis and scleritis were found in the right eye, together with dense vitritis and a large choroidal lesion that extended from the inferonasal to the superotemporal quadrants. B-scan ultrasonography of the right eye showed a choroidal detachment with scleral thickening and subtenon fluid. His IgM anti-Toxoplasma antibody was detected, and his QuantiFERON Gold testing was positive. Magnetic resonance imaging (MRI) of the orbit revealed an enhancing intraocular mass at the lateral and inferior aspects of the right globe. The diagnosis of right eye sclerouveitis with presumed tuberculosis and toxoplasmosis co-infections was made. He was treated with a course of oral azithromycin and anti-tubercular therapy along with systemic prednisolone and a topical steroid. The treatment reduced the inflammation; however, the patient suffered from a sequela of chronic uveitis with prolonged hypotony. Medical treatment alone may be insufficient in treating severe infective sclerouveitis, hence surgical intervention might be warranted to provide favorable clinical outcomes.

Recurrent Miller Fisher Syndrome

Miller Fisher syndrome (MFS) is an uncommon systemic autoimmune condition. Recurrent Miller Fisher syndrome is extremely rare. We want to highlight a rare case of recurrent Miller Fisher syndrome, which manifested as external and internal ophthalmoplegia, areflexia, and ataxia following an episode of upper respiratory tract infection (URTI). The patient developed a recurrent attack of Miller Fisher syndrome two months later with only internal and external ophthalmoplegia symptoms. Both episodes wholly resolved in a month without treatment. Miller Fisher syndrome can mimic various other neurological illnesses. Therefore, diagnosing this disease is often challenging. However, prompt diagnosis and management can be achieved with awareness of this rare illness.

Opportunistic Eye Screening Among First-Degree Relatives of Glaucoma Patients at a Suburban Tertiary Center in Malaysia

Background and objective

The majority of glaucoma patients are asymptomatic and are usually diagnosed at an advanced stage of the disease. This study aimed to assess the outcomes of glaucoma screening among known first-degree relatives of primary glaucoma patients.

Materials and methods

This study involved primary angle-closure glaucoma (PACG), primary open-angle glaucoma (POAG), and juvenile open-angle glaucoma (JOAG) patients who attended the glaucoma clinic at the Hospital Universiti Sains Malaysia between January 2014 and December 2015. First-degree relatives of the patients underwent a preliminary eye-screening evaluation, including visual acuity (Snellen chart), intraocular pressure (IOP) measurement (air-puff tonometry), and non-mydriatic fundus photography. Patients with visual acuity worse than 6/12, IOP measuring more than 21 mmHg or a difference of more than 3 mmHg between the eyes, and a vertical cup-disc ratio (VCDR) of 0.7 or higher were given a comprehensive eye examination.

Results

Seventy indexed glaucoma patients were recognized, and 368 first-degree relatives were identified. Forty-five relatives underwent the preliminary screening. Of these, 29 showed normal findings (62%), one had corneal pathology (2%), and 16 (36%) underwent a complete eye examination after failing the initial screening. Among the indexed JOAG group, five relatives (11%) were diagnosed as having JOAG; two were treated medically, while the remaining three required surgical intervention.

Conclusion

Opportunistic glaucoma screening of high-risk groups, especially JOAG is a feasible and cost-effective way to detect early glaucoma and prevent irreversible blindness. However, improvement in our healthcare system, including the involvement of multicentre clinics in other states in screening initiatives, is required to promote and facilitate the response to screening opportunities.

Ocular Cat Bite Injury: A Case Report and Literature Review

Ocular injury related to cat bites is rare, and no proper guidelines have been suggested for the treatment of such injuries. We report a rare case of zone II penetrating ocular injury secondary to a cat bite. A 49-year-old lady presented with left eye pain following a cat bite over the left eye, which occurred four hours prior to the presentation. Immediate primary closure with intravitreal antibiotic injections was given. Systemic and topical antibiotic treatments were administered. Presenting visual acuity was hand motion, which improved to 20/20 at six months follow-up. Throughout this period, there were no signs of endophthalmitis. Prompt and effective antibiotic administration with early surgical intervention contributed to a good visual prognosis in this case.

Clinical Audit on the Effectiveness of Clinic-Based Intraocular Pressure Phasing for Patients With Glaucoma and Glaucoma Suspect

Introduction: Glaucoma is a complex disease with intraocular pressure (IOP) playing an important role in its diagnosis and management. IOP has shown diurnal and nocturnal variations, which may affect the course of the disease.

Objective: The objective of this study was to determine the effectiveness of clinic-based office hour phasing in the diagnosis and management of glaucoma and glaucoma suspect (GS).

Methods: A retrospective clinical audit was conducted on patients who were subjected to office hour phasing in a glaucoma clinic, Hospital Universiti Sains Malaysia, Kelantan, Malaysia, between January 2015 and December 2019. The office hour phasing was conducted for various indications such as confirmation of diagnosis, screening, and effectiveness of treatment. IOP was recorded every two hours between 0800 and 1600 using an air puff tonometer by a trained nurse. Measurement of IOP was repeated with Goldmann applanation tonometer at sitting position by a trainee when the IOP ≥ 20 mmHg or discrepancy of IOP > 2 mmHg between two eyes. Other investigations including a Humphrey visual field and gonioscopy were conducted in between the IOP measurements. Diagnosis and clinical decisions on management were made at the end of the office hour clinic phasing.

Results: A total of 83 patients (163 eyes) were included in this clinical audit. Their mean age was 59.3 (16.5) years with 59% of male patients. Both eyes showed an almost similar pattern of mean IOP over five daytime readings in the clinic. A total of 35 eyes (21.5%) showed fluctuation ≥ 6 mmHg, and 128 eyes (78.5%) showed stable IOP during the clinic hour phasing. There was a significant difference in the mean IOP pattern between groups with stable and fluctuating IOP based on repetitive measure analysis of variance (RM ANOVA) (p = 0.008). The final diagnosis was made for 39 eyes (21 OD [right eye] and 18 OS [left eye]) out of 131 eyes (29.8%) with GS. Confirmation of diagnosis was achieved in all eyes (100%) with suspected ocular hypertension (OHT) and normal-tension glaucoma (NTG). Progression of glaucoma was confirmed in four eyes (2 OD and 2 OS) out of 17 eyes (23.5%) with suspected progression.

Conclusion: Clinic hour IOP phasing provides a practical approach in confirmation of diagnosis and adjustment in the management of patients with glaucoma and GS.

Orbital Cellulitis Secondary to Dental Abscess in Children

Paediatric orbital cellulitis is a potential sight- and life-threatening condition. It is a serious infection in children that can result in significant complications, including blindness, cavernous sinus thrombosis, cerebral venous sinus thrombosis, meningitis, subdural empyema, and brain abscess. Of the patients with orbital cellulitis, 17% died from meningitis, and 20% of the survivors had permanent loss of vision. Therefore, the potential for sight- and life-threatening complications makes prompt diagnosis and early treatment very important. We report here a case of a two-year-old girl who presented with a three-day history of left periorbital swelling, preceded by left upper perioral swelling that extended upward to the left cheek and left lower lid and was associated with low-grade fever. The patient had been admitted and was treated as having left preseptal with facial cellulitis; the patient was started on intravenous amoxicillin/clavulanic acid (200 mg three times per day dose), and chloramphenicol ointment was applied to the periorbital area. On day 3, the condition worsened, and dental examination showed multiple dental caries, upper gum swelling and abscess, and mobility of teeth 61 and 62 (two baby teeth). Contrast-enhanced computed tomography (CECT) of the orbit, paranasal, and brain showed a left periosteal abscess collection extending to the inferomedial region of the orbit. Examination and tooth extraction were performed under general anesthesia. The intraoperative results showed the presence of a left upper gum abscess, which was possibly the primary source of infection. Clinical improvement was observed postoperatively. Orbital cellulitis can be a complication of a dental abscess. This case emphasizes the importance of primary tooth care in children. A lack of care can result in fatal complications.

Effect of physical activity on severity of primary angle closure glaucoma

Objective:

To determine the association between physical activity and severity of primary angle closure glaucoma in Malay patients.

Methods:

A cross-sectional study was conducted involving 150 primary angle closure glaucoma patients between April 2014 and August 2016. Using the International Physical Activity Questionnaire, the physical activity status was assessed and divided into three categories: mild, moderate and heavy physical activity. The duration of physical activity and corresponding minimum energy requirements were calculated. Ocular examination was performed including Humphrey visual field 24-2 analysis assessment. Based on two consecutive reliable Humphrey visual fields, the severity of glaucoma was scored according to modified Advanced Glaucoma Intervention Study and classified as mild (0–5), moderate (6–11) and severe (12–20). Association between physical activity and Advanced Glaucoma Intervention Study score was determined with multiple linear regression analysis.

Results:

A total of 150 Malay patients with primary angle closure glaucoma were included (50 patients with mild, 50 with moderate and 50 with severe glaucoma). Physical activity showed inverse association with the severity of primary angle closure glaucoma. After calculating adjustments for age, sex, duration of glaucoma, body mass index, systemic co-morbidities, family history of glaucoma, myopia and educational status [adjusted b –3.41, 95% confidence interval (–5.23, –1.59), p < 0.001], there was also an inverse relationship with Advanced Glaucoma Intervention Study score. Every increase in physical activity level reduces the Advanced Glaucoma Intervention Study score by 3.4 point.

Conclusion:

Physical activity is the potential modifiable risk factor in reducing the severity of glaucoma among primary angle closure glaucoma patients. However, there is possibility of the severity of glaucoma restricted the physical activity of primary angle closure glaucoma patients.

Global Canny algorithm based on Canny edge detector framework in magnetic resonance imaging

Magnetic resonance imaging is an important modality in the diagnosis and pathology detection. Edge detection is used for image segmentation and feature extraction as part of the medical image analysis. There is no ideal and universal algorithm which performs perfectly under all conditions. Conventional Canny edge detector is not suitable to be used in Magnetic resonance images that contaminated by Rician noise. In this paper, we propose the use of customized non-local means into the Canny edge detector instead of Gaussian smoothing in the conventional Canny edge detector to effectively remove Rician noise while preserving edges in Magnetic resonance image of an internal organ. The result shows that our method can yield better edge detection than conventional method, with minimal false edge detection. The proposed method undergoes several attempts of parameter adjustment to detect true edges successfully using optimal parameter setting.

Lens-induced glaucoma in a tertiary centre in northeast of Malaysia

OBJECTIVE

To determine the clinical presentations, management and outcome of lens-induced glaucoma (LIG) in Hospital Universiti Sains Malaysia.

METHODS

A retrospective review was done among the existing patients of Hospital Universiti Sains Malaysia from January 2003 to December 2008. Patients with LIG were included and exclusion criteria were applicable for those who had glaucoma or other underlying causes of glaucoma. Demographic data, clinical presentations, management and outcome were recorded and analysed.

RESULTS

Thirty-eight patients (38 eyes) with LIG were included. The mean age was 70.2 years and predominantly women (22, 57.9%) were affected. Phacomorphic glaucoma (28, 73.7%) was the main cause of LIG, followed by phacolytic glaucoma (8, 21.1%). The main clinical symptoms were reduced vision (94.7%), eye pain (84.2%) and eye redness (81.6%). Most patients (32 eyes) were presented with visual acuity of hand movements (84.2%, or worse) and intraocular pressure more than 40 mm Hg (21, 55.3%). Nineteen patients (50.0%) underwent extra capsular cataract extraction with primary posterior chamber lens implantation. In 28 cases (73.7%), patients were able to stay free from pressure-lowering drugs after the operation. Intraocular pressure (IOP) reduced tremendously upon discharge with a mean of 15.2 mm Hg and vision had improved exceptionally (more than 6/36) as noted in 17 cases (44.7%).

CONCLUSION

Triad of acute reduced vision, eye pain and redness are the main clinical presentations of LIG. The main cause of LIG is phacomorphic glaucoma stemming from untreated senile cataract. Public awareness and early detection by primary physician is important for an early intervention of cataract. Early intervention aids in visual recovery and IOP control of LIG.

Traumatic optic neuropathy: a review of 24 patients

AIM

To evaluate the clinical presentations of traumatic optic neuropathy and to assess the visual outcome of three groups of patients managed differently (conservative, intravenous corticosteroids only and combination of intravenous and oral corticosteroids) at an academic tertiary care referral centre.

METHODS

A retrospective study was conducted involving 24 consecutive patients (27 eyes) with traumatic optic neuropathy attending Hospital Universiti Sains Malaysia from January 2007 till December 2009.

RESULTS

Twenty-four patients (27 eyes) were included. All cases involved were males. Mean age was 33 years old. Motor vehicle accident was the major cause (83.3%). Both eyes were equally involved. Most of the eyes had poor vision on presentation (HM-NPL, 81.5%) with associated periorbital haematoma (22 eyes) and subconjunctival haemorrhage (20 eyes). Majority of patients (19 patients, 79.2%) presented with more than one bony fracture of skull or orbit and 5 patients (20.8%) had no fractures. None of the patients had evidence of optic nerve compression on CT scans or MRI done. Eleven patients (45.8%) had been treated with intravenous and oral corticosteroids. The other 7 patients (29.2%) were treated conservatively and the third group (6 patients, 25.0%) was on intravenous corticosteroids only. Eleven of 12 eyes (91.7%) treated with intravenous and oral corticosteroids had shown 1 line improvement of visual acuity. Those eyes treated conservatively (77.8%) had shown 1 line improvement of visual acuity. As for patients treated with intravenous corticosteroids only, four patients remained NPL, one patient had mild visual improvement and the other one's vision remained the same. The visual improvement in patients treated with conservative management was not significant (P=0.386). Patients treated with intravenous corticosteroids alone have shown no visual improvement statistically(P<0.05). Patients treated with intravenous followed by oral corticosteroids had significant visual improvement (P<0.05). There was no statistically significant difference in visual outcome between patients treated with corticosteroids and patients treated conservatively (P=0.368). No patient underwent surgical decompression of the optic nerve. In this series, the follow up ranges from 6 months to 3 years.

CONCLUSION

Most of the traumatic optic neuropathy patients presented with periorbital haematoma, subconjunctival haemorrhage and orbital wall fractures. Patients treated with intravenous followed by oral corticosteroids have better visual outcome compared to conservative management.