Intracameral mydriatics versus topical mydriatics in pupil dilation for phacoemulsification cataract surgery.

PURPOSE: To evaluate the efficacy and safety of intracameral mydriatics (lidocaine 1.0% and phenylephrine 1.5%) versus topical mydriatics (phenylephrine 2.5% and tropicamide 1.0%) in pupil dilation for phacoemulsification surgery in Malaysians. SETTING: Department of Ophthalmology, Penang General Hospital, Georgetown Penang, Malaysia. DESIGN: Prospective comparative case series. METHOD: Patients with immature cataract were randomized to the topical mydriatic group (topical group) or intracameral mydriatic group (intracameral group). Patients with small pupils and complicated cataracts were excluded. Pupil diameter changes were measured throughout the surgery. Additional pupil dilation maneuvers and complications were recorded. RESULTS: The study comprised 112 patients. There was no difference in mean pupil dilation between the intracameral group (4.86 mm ± 0.74 [SD]) and the topical group (4.88 ± 0.91 mm) (P = .86). However, the mean pupil size before capsulorhexis in the topical group (7.23 ± 1.08 mm) was significantly larger than in the intracameral group (6.40 ± 0.80 mm) (P = .01). The pupils in the intracameral group continued to dilate during surgery (0.44 ± 0.62 mm), while those in the topical group constricted (-0.41 ± 1.04 mm) (P < .001). Three patients in the intracameral group and 6 in the topical group required additional maneuvers for pupil dilation (P = .49). Each group had 1 complication (P = 1.00). CONCLUSIONS: Intracameral mydriatic agents dilated heavily pigmented pupils for phacoemulsification cataract surgery. However, in the early stages of surgery, pupil dilation was slower than with topical agents.

Neuroretinitis with coexistent Bell's Palsy / 国际眼科杂志(Guoji Yanke Zazhi)

AlM:To report an unusual case of neuroretinits with coexistent Bell's Palsy.METHODS:A case report.RESULTS: A 16-year-old boy presented with right eye blurring of vision for one week. It was associated with high fever and facial asymmetry. The visual acuity of the right eye was 6/60 and the left eye was 6/6. Funduscopy of the right eye showed swollen and hyperemic optic disc with presence of macular star. There was also left lower motor neuron nerve palsy. Humphrey visual field perimetry showed small paracentral scotoma with enlargement of blind spot. Complete blood count showed neutrophilia with increased erythrocyte sedimentation rate (ESR). Serology for syphilis, toxoplasmosis, Lyme disease and cat-scratch disease was negative. Herpes simplex virus, Herpes zoster virus, and human immunodeficiency virus investigations were negative. Rickettsia was also negative. MRI of the brain and orbit were normal without demyelinating lesion. He was started with high dose intravenous methylprednisolone 250mg four times per day for three days. He was then discharged home with oral prednisolone 1mg/kg for another 11 days. During the follow-up,the visual acuity was improved to 6/6 after six months with slightly pale disc.The Bell's palsy was also improved without obvious facial asymmetry.CONCLUSION:It is important for clinician to examine other cranial nerces in optic neuritis. Although neuroretinitis with coexistent facial nerve in optic neuritis.Although neuroretinitis with coexistent facial nerve palsy is a rare conditon,thorough examinations and investigations should be made to exclude the inportant infetice causes.Optic neuritis with coexistent facial nerce palsy responds well to the high dose steroids.

Prevalence of refractive error in malay primary school children in suburban area of Kota Bharu, Kelantan, Malaysia

<p><b>INTRODUCTION</b>Refractive error remains one of the primary causes of visual impairment in children worldwide, and the prevalence of refractive error varies widely. The objective of this study was to determine the prevalence of refractive error and study the possible associated factors inducing refractive error among primary school children of Malay ethnicity in the suburban area of Kota Bharu, Kelantan, Malaysia.</p><p><b>MATERIALS AND METHODS</b>A school-based cross-sectional study was performed from January to July 2006 by random selection on Standard 1 to Standard 6 students of 10 primary schools in the Kota Bharu district. Visual acuity assessment was measured using logMAR ETDRS chart. Positive predictive value of uncorrected visual acuity equal or worse than 20/40, was used as a cut-off point for further evaluation by automated refraction and retinoscopic refraction.</p><p><b>RESULTS</b>A total of 840 students were enumerated but only 705 were examined. The prevalence of uncorrected visual impairment was seen in 54 (7.7%) children. The main cause of the uncorrected visual impairment was refractive error which contributed to 90.7% of the total, and with 7.0% prevalence for the studied population. Myopia is the most common type of refractive error among children aged 6 to 12 years with prevalence of 5.4%, followed by hyperopia at 1.0% and astigmatism at 0.6%. A significant positive correlation was noted between myopia development with increasing age (P <0.005), more hours spent on reading books (P <0.005) and background history of siblings with glasses (P <0.005) and whose parents are of higher educational level (P <0.005). Malays in suburban Kelantan (5.4%) have the lowest prevalence of myopia compared with Malays in the metropolitan cities of Kuala Lumpur (9.2%) and Singapore (22.1%).</p><p><b>CONCLUSION</b>The ethnicity-specific prevalence rate of myopia was the lowest among Malays in Kota Bharu, followed by Kuala Lumpur, and is the highest among Singaporean Malays. Better socio-economic factors could have contributed to higher myopia rates in the cities, since the genetic background of these ethnic Malays are similar.</p>

Heat-balling wasps by honeybees.

Defensiveness of honeybee colonies of Apis cerana and Apis mellifera (actively balling the wasps but reduction of foraging) against predatory wasps, Vespa velutina, and false wasps was assessed. There were significantly more worker bees in balls of the former than latter. Core temperatures in a ball around a live wasp of A. cerana were significantly higher than those of A. mellifera, and also significantly more when exposed to false wasps. Core temperatures of bee balls exposed to false wasps were significantly lower than those exposed to V. velutina for both A. cerana and for A. mellifera. The lethal thermal limits for V. velutina, A. cerana and A. mellifera were significantly different, so that both species of honeybees have a thermal safety factor in heat-killing such wasp predators. During wasps attacks at the hives measured at 3, 6 and 12 min, the numbers of Apis cerana cerana and Apis cerana indica bees continuing to forage were significantly reduced with increased wasp attack time. Tropical lowland A. c. indica reduced foraging rates significantly more than the highland A. c. cerana bees; but, there was no significant effect on foraging by A. mellifera. The latency to recovery of honeybee foraging was significantly greater the longer the duration of wasp attacks. The results show remarkable thermal fine-tuning in a co-evolving predator-prey relationship.