Anterior segment changes after pharmacologic mydriasis using Pentacam and optical coherence tomography in angle closure suspects

AIM: To compare the dynamic changes of anterior segment parameters especially iris morphology induced by pharmacologic mydriasis between angle closure suspects and normal controls. METHODS: The study group comprised 19 eyes of 19 angle closure suspects and 19 eyes of 19 age- and sexmatched normal open-angle eyes. Pentacam and optical coherence tomography measurements before and 30min after instillation of compound tropicamide eye drop were performed and compared. Biometric evaluations of iris tomography and anterior chamber angle were estimated by a customized image-processing software. RESULTS: Baseline axial length, iris cross sectional area and volume did not differ significantly between angle closure suspects and normal controls. Angle closure suspects had smaller pupil size, narrower anterior segment dimension and axial length, thinner iris with greater curve in comparison with normal controls. Pharmacologic mydriasis led to significant increments in iris thickness at 750 mu m, anterior chamber depth and volume, whereas significant decrements in iris curve, cross sectional area and volume in both groups. Angle opening distance at 500 mu M was increased significantly in normal controls (from 0.465 +/- 0.115 mm to 0.539 +/- 0.167 mm, P=0.009), but not in angle closure suspects (from 0.125 0.100 mm to 0.145 +/- 0.131 mm, P=0.326). Iris volume change per millimeter of pupil dilation (Delta IV/Delta PD) decreased significantly less in angle closure suspects than normal controls (-2.47 +/- 1.33 mm(2) vs -3.63 +/- 1.58 mm(2), P=0.019). Linear regression analysis showed that the change of angle opening distance at 500 mu M was associated most with the change of central anterior chamber depth (beta= 0.841, P=0.002) and Delta IV/Delta PD (beta=0.028, P=0.002), followed by gender (beta=0. 062, P=0.032). CONCLUSION: Smaller iris volume decrement per millimeter of pupil dilation is related significantly with the less anterior angle opening in angle closure suspects after pharmacologic mydriasis. Dynamic iris change may be as a prospective indicator of iris compressibility and angle closure glaucoma.

Multisystem smooth muscle dysfunction syndrome in a Chinese girl:A case report and review of the literature

BACKGROUND Multisystemic smooth muscle dysfunction syndrome(MSMDS) is a rare genetic disease worldwide. The main mutation is the actin alpha 2(ACTA2) gene p.R179 H. In this paper, we report a Chinese MSMDS patient and systematically review the previous literature.CASE SUMMARY Here, we report a 9.6-month-old Chinese girl who was diagnosed with MSMDS based on her history and symptoms, such as recurrent cough, wheezing, and complications with congenital fixed dilated pupils. Chest high-resolution computed tomography revealed inhomogeneous lung transparency, obvious exudative lesions, and some lung fissures that were markedly thickened. Cranial magnetic resonance imaging excluded bleeding and infarction but showed abnormal signals in the centrum ovale majus and bilateral periventricular regions. Echocardiography only showed patent foramen ovale, and no patent ductus arteriosus, pulmonary artery dilatation, or pulmonary hypertension was found. Bronchoscopy indicated moderate bronchial malacia. These examinations in conjunction with the typical eye abnormality suggested a diagnosis of MSMDS, and sequencing of exon 6 of the ACTA2 gene demonstrated the heterozygous mutation c.536 G>A, p.R179 H. However, her parents' gene analyses were normal.CONCLUSION MSMDS is a rare genetic disease mainly caused by the mutation of the ACTA2 gene p.R179 H. Early genetic diagnosis should be performed for children presenting with congenital fixed dilated pupils and patent ductus arteriosus.During the process of diagnosis and treatment, clinicians should be on high alert for cerebrovascular, cardiovascular, and pulmonary complications.

Comparative study measuring the dilatory effect of a mydriatic device(Mydriasert~) versus topical drops

AIM:To compare the mydriatic efficacy of an ophthalmic insert(Mydriasert,MY)versus phenylephrine and tropicamide(PT)eye drops.METHODS:Two controlled,prospective,randomized,single-blind studies were performed.In the first study,a total of 80 eyes from 40 outpatient-clinic patients were analyzed.PT drops were applied to the right eye,and a MY device was inserted in the left eye for 30min.Time until maximal pupil dilation for each eye was then assessed.In the second study,80 eyes from 80 patients undergoing cataract surgery were analyzed.Pupil dilation was achieved using either PT drops three-times for one hour prior to surgery(40 patients),or a MY device was inserted one hour prior to surgery(40 patients).RESULTS:In the first study,MY achieved superior mydriasis compared to PT eye drops at 90min(9.04±1.33mm vs 8.78±1.37mm,P=0.012).However MY took longer than PT drops to achieve maximal dilation,and mydriasis was inferior in eyes with MY compared to PT drops at 30min(7.21±1.73mm vs 8.22±1.43mm,P【0.001),the two groups only becoming similar by 60min(8.85±1.44mm vs 8.71±1.27mm,P=0.236).In the second study,both MY and PT achieved similar levels of mydriasis at the beginning of surgery(8.75±0.76mm with MY vs 8.77±0.63mm with PT),and also at the end of surgery(7.96±1.06mm with MY vs 8.32±0.72mm with PT),with no significant difference between groups(P=0.08).MY was well tolerated and cardiovascular effects were not influenced by dilation method.CONLUSION:MY could be a safe and efficacious alternative for mydriasis.The mydriatic effect of MY is as good as conventional PT eye drops after 60min,and is superior after 90min.MY also maintains good pupil dilation during cataract surgery.