Refining the Diagnostic Technique to Determine Prevalence of Demodex Mites in Eyelash Hair Follicles Within Standard Ophthalmic Practice: A Single-Center Outpatient Clinical Study

Charlotte Boel,1,2 Elianne Westerveld,3 Daniëlla Kloos,3 Fleur Goezinne1 1Eyescan Rijswijk, Rijswijk, the Netherlands; 2Department of Ophthalmology, University Hospital Brussels, Brussels, Belgium; 3Eyescan Warmond, Warmond, the NetherlandsCorrespondence: Fleur Goezinne, Eyescan Rijswijk, Madame Curielaan 6, Rijswijk, 2289 CA, the Netherlands, Tel +31 88 1111 945, Email [email protected]: A high density of Demodex infestation in human eyelids and eyelash follicles has been implicated in a variety of ocular surface conditions. However, Demodex infestation often goes undiagnosed and untreated, due to an overlap in signs and symptoms with other sources of ocular surface inflammation. We sought to refine the diagnostic technique for outpatient assessment for Demodex infestation and determine prevalence of Demodex mites in the hair follicles of eyelashes from patients in a standard ophthalmic practice.Patients and Methods: Patients recruited from a single outpatient ophthalmology clinic were examined for the presence of Demodex mites following standard ophthalmic consultation. During anterior segment biomicroscopic examination, investigators searched for cylindrical dandruff and collarettes around the base of patient eyelashes. These were removed, and individual eyelashes manipulated with tweezers to reveal Demodex mites. Presence of Demodex, cylindrical dandruff and collarettes, time taken to identify the first Demodex mite, mean number of Demodex mites per hair shaft, and patient-reported symptoms of blepharitis were recorded and analyzed to determine potential correlations.Results: A total of 173 patients were recruited, of whom 106 were included in Demodex prevalence analyses. Demodex infestation was identified in 100/106 (94%) patients, with a mean time of 2 minutes and 20 seconds taken to find the first Demodex mite and a mean number of 3 mites identified per hair shaft. Presence of Demodex significantly correlated with the presence of cylindrical dandruff (98/106 [92%] patients; p < 0.001), but not with the presence of collarettes (62/106 [58%] patients; p = 0.230) or symptoms of blepharitis (15/106 [14%] patients; p = 0.591).Conclusion: These results highlight the pervasiveness of Demodex infestation, predicted by the presence of cylindrical dandruff, in the eyelashes of patients in a standard ophthalmic practice. They support the use of a non-invasive diagnostic technique to allow fast, simple identification of Demodex by ophthalmologists and optometrists in outpatient clinical practice.Keywords: Demodex folliculorum, Demodex brevis, blepharitis, diagnosis, incidence, ophthalmic clinical practic

Incidence of redetachment 6 months after scleral buckling surgery.

Purpose: The preoperative and intraoperative clinical variables associated with redetachment and/or a poor visual outcome following scleral buckling (SB) surgery for rhegmatogenous retinal detachment (RRD) have mainly been studied after a short follow-up. This study aimed to analyse long-term effects by following patients for at least 6 months. Methods: In a retrospective survey we evaluated the data of 436 eyes that underwent SB surgery. Postoperative data were collected at 3-month intervals. Results: After a mean follow-up period of 51 months, anatomic reattachment was achieved in 76% after one SB procedure, with a final reattachment rate of 97% after additional vitreoretinal procedures. In total, 104 eyes developed redetachment during follow-up. After more than 6 and 12 months of follow-up, 32 eyes (7%) and 20 eyes (5%), respectively, developed redetachment. Multivariate regression analysis showed that recurrent redetachment and more than 7 days of visual field loss were significant predictors for a poor postoperative visual outcome at 12 months. A cumulative size of the tear of more than three disc diameters was a significant predictor of recurrent RRD. Conclusion: Conventional SB surgery is a reliable procedure in a selected group of eyes with primary RRD. However, in eyes with a retinal tear with a cumulative size of more than three disc diameters, a primary vitrectomy should be considered. Taking into account that 7% of eyes developed redetachment after 6 months, a longer follow-up period seems necessary to evaluate the anatomical and visual outcomes after SB surgery

Low redetachment rate due to encircling scleral buckle in giant retinal tears treated with vitrectomy and silicone oil

BACKGROUND: The goal of this study was to identify risk factors for redetachment and to assess long-term anatomic and functional results of pars plana vitrectomy (PPV) for retinal detachment associated with giant retinal tears (GRT). SUBJECTS AND METHODS: In a retrospective study the authors analyzed 30 eyes which were operated with PPV for GRT retinal detachment in their clinic between March 1998 and August 2003. RESULTS: Redetachment rate after one vitrectomy procedure in this series of 30 eyes was 30% (n = 9), and ultimately, the retina was attached in 29 (96.7%) eyes. After multivariate analysis the absence of an encircling scleral buckle (P = 0.008) was significantly associated with redetachment. Visual acuity improved in 54% of the eyes. CONCLUSION: Vitrectomy with an encircling scleral buckle seems to be a preferred treatment for complicated retinal detachments due to GRT

Corneal endothelial cell density after vitrectomy with silicone oil for complex retinal detachments

PURPOSE: To evaluate the endothelial cell density changes in eyes with silicone oil tamponade after vitrectomy for complex rhegmatogenous retinal detachment. METHODS: A prospective controlled study with 81 eyes with complex rhegmatogenous retinal detachment undergoing vitrectomy and silicone oil tamponade. Fellow eyes that fulfilled specific inclusion criteria served as controls. Endothelial cell density (in cells per square millimeter), coefficient of variance (standard deviation per mean cell area x 100), percentage of hexagonal cells, and corneal thickness were documented preoperatively and compared with values obtained at 3, 6, and 12 months postoperatively. For the purpose of the study analysis, all study eyes were divided into 5 groups, according to their lens status during the follow-up. RESULTS: High endothelial cell density loss was found in Group 3, (eyes that underwent an additional phacoemulsification procedure) and Group 4 (eyes that underwent lens and/or intraocular lens removal during the follow-up) at 12 months with a mean cell loss of 19% and 39%, respectively (P < 0.001). CONCLUSION: An intact natural or artificial lens-iris diaphragm may provide a protective barrier against corneal endothelial cell damage from long-term silicone oil tamponade