Predictive factors affecting the short term and long term exodrift in patients with intermittent exotropia after bilateral rectus muscle recession and its effect on surgical outcome.

PURPOSE: To determine the predictive factors that affect short term and long term postoperative drift in intermittent exotropia after bilateral lateral rectus recession and to evaluate its effect on surgical outcome. METHODS: Retrospective review of 203 patients with diagnosis of intermittent exotropia, who had surgical corrections with more than 3 years of followup. Different preoperative parameters were obtained and evaluated using Pearson's correlation analysis. RESULTS: The proportion of exodrift increased from 62% at 6 weeks to 84% at 3 years postoperatively. The postoperative drift was 4.3 ± 8.1 PD at 6 weeks, 5.8 ± 8.4 PD at 6 months, 7.2 ± 8.3 PD at 1 year, 7.4 ± 8.4 PD at 2 years, and 7.7 ± 8.5 PD at 3 years. Preoperative deviation and initial overcorrection were significant factors affecting the postoperative drift at 3 years (r = 0.177, P = 0.011, r = -0.349, and P < 0.001, resp.). CONCLUSIONS: Postoperative exodrift along three years occurs in a majority of patients after bilateral lateral rectus recession for intermittent exotropia. The long term surgical success is significantly affected by this postoperative exodrift. A larger preoperative deviation and a larger initial overcorrection are associated with a larger early and late postoperative exodrift.

A prospective study of fusional convergence parameters in Chinese patients with intermittent exotropia.

PURPOSE: To evaluate the correlation between different fusional convergence parameters and the Newcastle Control Score (NCS) in children with intermittent exotropia. METHODS: In this consecutive prospective observational series, 101 Chinese children with intermittent exotropia were examined by a single observer, who assessed the level of control using the revised NCS and measured the angle of deviation and fusional convergence. Levels of control were defined according to the NCS as good (0-3), moderate (4-6), or poor (7-9). The correlation between the different fusional convergence parameters and the NCS was evaluated. RESULTS: The total convergence amplitude was similar among the different control groups (P = 0.288 and P = 0.628 at near and at distance, respectively). The convergence reserve was higher in the good control group compared with the moderate and poor control groups, both at near (P = 0.001) and at distance (P = 0.001). Among all fusional convergence parameters, we determined that the fusional reserve ratio had strongest correlation with control (near ratio: r = -0.66, P = 0.001; distant ratio: r = -0.59, P = 0.001). Among patients with a fusional reserve ratio ≥ 2 at distance, 100% (5 of 5 patients) of these patients demonstrated good control (NCS ≤ 3). CONCLUSIONS: In children with intermittent exotropia, the total convergence amplitude was similar among different levels of control. The convergence reserve was lower in the poor control group. Fusional reserve ratio ≥ 2 was an indicator of good control in patients.

Prognostic factors predicting the surgical outcome of bilateral lateral rectus recession surgery for patients with infantile exotropia.

PURPOSE: To determine the presurgery factors affecting early and long-term favorable outcomes of bilateral lateral rectus recession surgery for infantile exotropia. PATIENTS AND METHODS: A retrospective study of 50 patients with infantile exotropia (both constant-type and intermittent-type exotropia with onset before 1 year of age) who had bilateral lateral rectus recession surgery correction with more than 1 year follow up. Presurgery data were obtained and evaluated by use of multiple regression analysis. RESULTS: Smaller presurgery distance deviation (p = 0.042), older age at surgery (p = 0.025), longer interval between onset and surgery (p = 0.020), and more myopic refractive error (p = 0.007) were associated with successful outcome at 6 weeks, but none was correlated with successful outcome at 1 year. Among all data, presurgery distance deviation was the only significant determinant (multiple regression analysis, p = 0.021) for successful outcome at 6 weeks. Presurgery distance deviation (ß = 0.952, p < 0.001) was correlated with the distant angle of deviation 6 weeks (ß = 0.952, p < 0.001) and 1 year (ß = 0.394, p = 0.006) postsurgery. CONCLUSIONS: Smaller presurgery deviation was found to be associated with more favorable surgical outcome.

Preoperative factors predicting the surgical response of bilateral lateral rectus recession surgery in patients with infantile exotropia.

PURPOSE: To determine the preoperative factors affecting the efficacy in bilateral lateral rectus recession surgery for infantile exotropia. METHODS: This was a retrospective study of 50 patients with infantile exotropia who had bilateral lateral rectus recession surgery correction with more than 1 year of follow-up. Preoperative parameters influencing the response of the surgery were obtained and evaluated using multiple regression analysis including age at onset, age at surgery, interval between onset and surgery, preoperative deviation, refractive error, anisometropia, amount of surgery performed, presence of A- or V-pattern, and preoperative phase of exotropia. The response to surgery was defined as the change in deviation divided by the amount of the surgery. RESULTS: Thirty-two (64%) and 24 (48%) patients had successful outcome at 6 weeks and 1 year postoperatively, respectively. The mean response to surgery was 1.79 ± 0.63 prism diopters (PD)/mm recession at 6 weeks and 1.58 ± 0.75 PD/mm recession at 1 year postoperatively. Exotropic drift was 5.12 ± 7.27 PD at 6 weeks and 8.02 ± 6.81 PD at 1 year postoperatively. Pre-operative deviation was correlated with the response of surgery at 6 weeks (ß = 0.342, P = .020) and 1 year (ß = 0.391, P = .007) postoperatively. CONCLUSIONS: Surgical response decreases over time due to the exotropic drift. Larger preoperative distance deviation was associated with larger surgical response. Both the exotropic drift and the preoperative deviation should be considered in applying the surgical dose in infantile exotropia.

Intravitreal bevacizumab: safety of multiple doses from a single vial for consecutive patients.

OBJECTIVES: To report the incidence of endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor and the safety profile of multiple doses of bevacizumab from the same vial reused for multiple patients. DESIGN: Case series. SETTING: A private hospital in Hong Kong. PATIENTS: A systematic retrospective review of consecutive intravitreal anti-vascular endothelial growth factor injections between 5 June 2006 and 17 December 2010 at a single institute was conducted. Patients were identified from prospectively designed audit forms, and each patient's medical record was reviewed for any documented complications. Bevacizumab 1.25 mg/0.05 mL to 2.50 mg/0.1 mL was aspirated from the designated vial, with a maximum of 10 consecutive injections being aspirated from the same vial. The opened vial was then discarded without overnight storage. Ranibizumab was aspirated from the commercially available 1 mg/0.1 mL single-use vial. RESULTS: A total of 1655 intravitreal anti-vascular endothelial growth factor injections into 392 eyes of 383 patients were evaluated during the study period. There were 1184 bevacizumab injections and 471 ranibizumab injections. There was one case of suspected endophthalmitis after ranibizumab injection, though culture of the vitreous tap was negative. The point prevalence of endophthalmitis was 0.06% (1/1655) for the total number of injections: 0.21% (1/471) after ranibizumab, and 0% after bevacizumab. CONCLUSION: Although many centres aliquot multiple syringes from a single vial to be kept in a refrigerator for use, the current study shows that so long as proper sterile techniques are implemented, there were no cases of endophthalmitis from using the same vial, which was reused for a maximum of 10 consecutive injections. For intravitreal injection, bevacizumab costs approximately US$50 to US$100 per dose, as opposed to US$2000 per dose for ranibizumab. Sharing multiple doses of bevacizumab from a single vial can substantially reduce the cost of treatment.

Corneal collagen cross-linking demarcation line depth assessed by Visante OCT After CXL for keratoconus and corneal ectasia.

PURPOSE: To report the demarcation line depth after corneal collagen cross-linking (CXL) for keratoconus and postoperative LASIK ectasia with Visante (Carl Zeiss Meditec) optical coherence tomography (OCT) and investigate correlations between this depth and preoperative parameters and postoperative visual and keratometry outcomes. METHODS: Retrospective interventional case series of 40 eyes with keratoconus or postoperative LASIK ectasia treated with riboflavin ultraviolet-A CXL. Ophthalmic evaluation included uncorrected distance visual acuity, corrected distance visual acuity (CDVA), corneal topography (Pentacam, Oculus Optikgeräte GmbH), and postoperative anterior segment OCT. Correlation analyses were performed. Statistical significance was indicated by P<.05. RESULTS: At 6 months postoperative, mean demarcation line depth was 281.4±53.3 µm. Thinner minimal corneal thickness (r=0.413, P=.008), older age (r=-0.490, P=.001), higher grading of ectasia (for both keratoconus and postoperative LASIK ectasia) (r=-0.332, P=.044), female sex (r=0.343, P=.030), postoperative LASIK ectasia (r=-0.420, P=.007), and longer duration of disease (r=-0.377, P=.023) were correlated with shallower demarcation line depth. Forward stepwise multiple linear regression analysis showed that among all preoperative factors, minimal corneal thickness (standardized ß=0.473, P=.003) and age (standardized ß=-0.317, P=.036) were significantly associated with demarcation line depth. The CXL demarcation line depth and change in CDVA (r=-0.16, P=.325) and change of the steepest keratometry at 6 months (r=0.084, P=.637) were not correlated. CONCLUSIONS: The Visante OCT can be used for assessing CXL demarcation line depth. The demarcation line depth may decrease with the severity of ectasia and age.

Long-term ocular alignment after bilateral lateral rectus recession in children with infantile and intermittent exotropia.

PURPOSE: To compare postoperative drift after bilateral lateral rectus recession for infantile exotropia (XT) and for intermittent XT and to compare initial postoperative alignment with long-term motor outcome. METHODS: Medical records of all patients with infantile exotropia or intermittent exotropia who had undergone bilateral lateral rectus muscle recession surgery with a follow-up longer than 3 years were reviewed. The pre- and postoperative angles of deviation at distance and at near and postoperative drift at distance were compared. Surgical outcome was categorized as "success" (esotropia <6(Δ) or exotropia <11(Δ)), "recurrence" (>10(Δ) exotropia), or "overcorrection" (>5(Δ) of esotropia). RESULTS: The overall mean postoperative exotropic drift at 3 years was 10.4(Δ) in the infantile XT group and 7.2(Δ) in the intermittent XT group (P = 0.05). Both groups had a low success rate at 3 years: 41% in the infantile XT group and 51% in the intermittent XT group (P = 0.270). For patients with an initial esotropia of 0(Δ) to 10(Δ), the success rate at 3 years was 86% in the infantile XT group (12 of 14) and 65% in the intermittent XT group (28 of 43). CONCLUSIONS: Postoperative exotropic drift is clinically similar in patients with intermittent versus infantile exotropia. Esotropia of 0(Δ) to 10(Δ) during the early postoperative period may be associated with the best long-term ocular alignment.

Refractive changes after pediatric intraocular lens implantation in Hong Kong children.

PURPOSE: To report the refractive changes after cataract surgery and intraocular lens (IOL) implantation in Hong Kong Chinese children. METHODS: The clinical records of all patients who had cataract extraction and IOL implantation before age 18 years and with more than 2 years of follow-up were studied retrospectively. The refractive errors of all patients determined by cycloplegic refraction at 6 weeks, 3 months, 6 months, and 1 year postoperatively and then annually thereafter were included for analysis. Patients were stratified into groups according to their age at IOL implantation for analysis. RESULTS: Twenty-six eyes (81.3%) had developmental cataracts, 3 eyes (9.4%) had traumatic cataracts, and 3 eyes (9.4%) were iatrogenic (from surgical or medical treatment). Patients demonstrated a mean myopic shift (diopters) of -5.53 (0 to 2 years old) -4.68 (3 to 5 years old), -2.60 (6 to 8 years old), -0.42 (9 to 11 years), and -0.09 (> 11 years). There was no significant difference in myopic shift between eyes that were operated on and those that were not. No statistically significant differences in refractive change were found in comparing males to females, unilateral to bilateral cases, traumatic to non-traumatic cases, amblyopic to nonamblyopic eyes, primary to secondary intraocular lenses, or polymethylmethacrylate to acrylic IOLs. CONCLUSION: The postoperative myopic shift in pediatric patients undergoing IOL implantation is greatest in the younger age groups and persists until at least 8 years of age. The mean rate of myopic shift also decreases with age. The refractive development of the pseudophakic eyes was not significantly different from the fellow phakic eyes.

Anti-vascular endothelial growth factor for myopic choroidal neovascularization.

Myopic choroidal neovascularization (CNV) is a vision-threatening complication in the eyes with pathological myopia, which is particularly prevalent among young and middle-aged Asians globally. To date, the verteporfin in photodynamic therapy study is the only randomized-controlled study in treatment of subfoveal myopic CNV. However, its long-term benefit is controversial. Recently, intravitreal injections of anti-vascular endothelial growth factors have shown promising results. In the absence of randomized-controlled trial comparing the efficacy of anti-vascular endothelial growth factors with photodynamic therapy and placebo, the purpose of this article is to review the current studies on functional and anatomical outcomes in both subfoveal and juxtafoveal myopic CNV. Furthermore, the influences of various doses and frequencies, as well as age and previous photodynamic therapy treatment on its effect are described.

Reemergence of syphilitic uveitis masquerading as other diseases: a report of two cases.

During a 6-month period in 2010, 2 patients with uveitis were examined at our department and diagnosed with ocular syphilis. They initially presented with symptoms and signs resembling Harada's disease and Behçet's disease and were therefore treated with systemic steroids with suboptimal responses. When laboratory workup revealed neurosyphilis, they were given a course of intravenous penicillin G, which led to significant clinical and visual improvement. Epidemiological data indicates a worldwide reemergence of syphilis and a high degree of suspicion is necessary in view of its multitude of presenting ocular signs without pathognomonic features.

Exotropic drift and ocular alignment after surgical correction for intermittent exotropia.

PURPOSE: To evaluate changes in the angle of deviation over time and compare the motor success rate with different initial postoperative deviation in patients undergoing surgical correction for intermittent exotropia. METHODS: Forty-eight patients aged between 1 and 10 years who underwent bilateral lateral rectus recession for intermittent exotropia were retrospectively evaluated. Preoperative and postoperative ocular deviations at 1 week, 1 month, and 6 months were analyzed. Full surgical correction was attempted in all patients. Motor success was defined as ocular deviation within 10 prism diopters of orthophoria at 6 months postoperatively. RESULTS: The follow-up period ranged from 6 months to 3 years. Although most patients had exotropic drift, this drift was greater in patients with initial esotropia (86.7%) and orthophoria (70.0%) compared to patients with exotropia (26.1%). Motor success was achieved in 29 (60.4%) patients. There was no statistical difference between ocular alignment at 1 week postoperatively and final motor success (P = .782). There was good correlation between ocular alignment at 1 week and 6 months postoperatively (rho = 0.585, P < .001). Age and preoperative deviation were not found to be associated with motor success. CONCLUSIONS: The success rate appears to be unaffected by initial ocular alignment, suggesting that deliberate initial overcorrection may be unnecessary. Future studies are warranted to evaluate the long-term stability of this alignment.

Retinal nerve fiber layer thickness after a single attack of primary acute angle-closure glaucoma measured with optical coherence tomography.

BACKGROUND AND OBJECTIVE: After a single unilateral acute primary angle-closure glaucoma attack, retinal nerve fiber layer (RNFL) may be thinned. The current study measured the RNFL thickness using optical coherence tomography in eyes with normal visual fields after recovery from a single attack of acute primary angle-closure glaucoma. PATIENTS AND METHODS: Twenty-one patients and age-matched control subjects underwent optical coherence tomography scanning after recovery from a single unilateral acute primary angle-closure glaucoma attack. Data from the affected eyes, normal fellow eyes, and control subjects were compared. RESULTS: Average RNFL thickness was 91.3 +/- 16.4 microm in the affected eyes, 100.1 +/- 16.4 microm in the fellow eyes, and 100.2 +/- 16.7 microm in the control eyes. Significant thinning was present in the affected eyes compared to the fellow eyes (P = .001) and the control eyes (P = .04). CONCLUSION: RNFL thickness was found to be significantly thinner in the eyes with angle-closure glaucoma.

Bilateral deepening of upper lid sulcus from topical bimatoprost therapy.

PURPOSE: To report a new adverse effect related to treatment with bimatoprost. METHOD: Case report. A 43-year-old Asian female with bilateral glaucoma was noticed to have bilateral deepening of upper lid sulcus 3 months after beginning treatment with bimatoprost 0.03%. RESULTS: Bimatoprost was discontinued due to cosmetic reasons, and there was improvement of the lid sulcus deepening bilaterally 4 weeks after stopping the drug. CONCLUSIONS: Deepening of upper lid sulcus is one of the adverse effects related to treatment with bimatoprost. This effect may be more prominent in Asians who have relatively full upper lid sulcus.

Clinical features and outcomes of Fusarium keratitis associated with contact lens wear.

PURPOSE: To describe the clinical features and outcomes among contact lens wearers with Fusarium keratitis. METHODS: A retrospective observational review of all cases of culture-proven Fusarium keratitis among contact lens wearers from three hospitals in Hong Kong Island were included. The clinical features, hygiene habits, and clinical outcomes were reviewed. RESULTS: Sixteen patients (17 eyes) were diagnosed with Fusarium keratitis associated with contact lens wear. One patient had bilateral involvement. Six patients had a central lesion; four had paraxial lesions; one had paraxial and peripheral lesions; and the rest had peripheral lesions. Ten (62.5%) patients reported using ReNu multipurpose cleaning solution. Most patients had poor contact lens hygiene habits. One patient required systemic antifungal treatment. No surgical intervention was required in any of the patients. CONCLUSIONS: The clinical features of Fusarium keratitis in contact lens wearers can be variable. Although fungal infection is reported rarely, clinicians should maintain a high index of suspicion for it when examining patients with contact lens-associated microbial keratitis. Education on proper contact lens care should be reinforced. Early and appropriate treatment may lead to satisfactory visual outcomes.

Recent pattern of contact lens-related keratitis in Hong Kong.

PURPOSE: To describe the changing pattern of clinical features and microbiology of contact lens-associated microbial keratitis in Hong Kong. METHODS: This is a retrospective observational case series of patients diagnosed with contact lens-associated microbial keratitis between July 2004 and April 2005 and between July 2005 and April 2006. Patients who wore contact lenses solely for the correction of refractive error and who were seen at Queen Mary Hospital were included in the study. The clinical characteristics, microbiology, and visual outcomes were compared. RESULTS: There were 14 cases between July 2004 and April 2005. Most cases had an axial lesion (eight) or paraxial lesions (four). Corneal scrapings were positive in seven (50%) patients, among whom six showed Pseudomonas aeruginosa and one showed Serratia marcescens as the pathogens. Contact lens storage cases yielded polymicrobial growth in two cases. For the more recent cohort, Fusarium species had been identified as the dominant pathogen, and most (60%) contact lens storage cases showed polymicrobial growth. CONCLUSIONS: There has been an increased number of cases of contact lens-associated fungal keratitis recently. Fusarium species and polymicrobial growth are becoming more dominant.

Orbital involvement in Erdheim-Chester disease.

Erdheim-Chester disease is a rare, idiopathic, non-Langerhans' cell, histiocytic disorder. To our knowledge this is only the second case of Erdheim-Chester disease reported in the Chinese population. We describe a 45-year-old woman presenting with unilateral proptosis and periorbital xanthelasma. Histopathological examination revealed a xanthogranulomatous lesion expressing CD68, but negative for S100 protein, CD1a, CD3, or CD20. Systemic involvement was evident on bone scanning, and involvement of the thorax and abdominal aorta was seen on computed tomography. Despite treatment with systemic steroids, immunosuppressants, chemotherapy and interferon, progressive deterioration occurred. Our patient's clinical course was consistent with reports in the literature. Unfortunately, our patient developed neutropenic fever and died from septicaemic shock. Although Erdheim-Chester disease is a rare entity, especially in the Chinese population, an unusual presentation with orbital masses and bilateral xanthelasma, associated with systemic features, should raise the suspicion of this serious and potentially fatal disease.

Evaluation of quality of life in patients with cataract in Hong Kong.

PURPOSE: To evaluate the quality of life in patients in a public hospital in Hong Kong before and after cataract surgery using a new questionnaire. SETTING: Department of Ophthalmology, Tung Wah Eastern Hospital, Hong Kong, China. METHODS: One hundred ten Chinese patients having cataract extraction were evaluated for surgical outcomes and quality of life using a questionnaire modified to reflect the local culture and environment in Hong Kong. The questionnaire consisted of 20 questions divided into 4 domains: distance vision, near vision, social function, and cataract-related symptoms. The test-retest reliability of the questionnaire was assessed in another 15 patients by weighted kappa and internal consistency tested with the Cronbach alpha. Construct validity was tested by correlating visual acuity with quality of life and subjective visual improvement and satisfaction with quality-of-life improvement. The preoperative and 4-month postoperative quality of life were evaluated, and the association with the patients' characteristics, type of surgery performed, presence of systemic or ocular diseases, and subjective patient satisfaction was analyzed. RESULTS: The preoperative visual acuity in the operated eye had a low correlation (0.11) with the quality-of-life score; visual acuity in the better eye had a higher correlation (0.29). Quality-of-life improvement was moderately correlated with visual acuity improvement and patient satisfaction. Overall, quality-of-life scoring improved in all domains after surgery, with an overall effect size of 0.68. Quality-of-life scores improved postoperatively in 83.6% of patients, did not change in 3.6%, and were worse in 12.7%. Visual acuity improved in 94.5%, remained the same in 2.7%, and was worse in 2.7%. There was no difference in quality-of-life improvement between extracapsular cataract extraction and phacoemulsification at 4 months. Patients with systemic or ocular diseases and those who were phakic in the fellow eye had lower quality-of-life improvement; however, this was statistically significant for systemic diseases only. Age and sex did not affect quality of life or its improvement. CONCLUSIONS: The quality of life and surgical outcomes in cataract patients were assessed by a simple questionnaire. The local culture and environment should be taken into consideration in the questionnaire design.