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

Purpose: 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.

Vascular risk factors for optical coherence tomography-detected macular cysts: The Maastricht Study.

PURPOSE: To investigate whether higher blood pressure and greater arterial stiffness are associated with the presence of macular cysts and whether this association is already present in the absence of micro-aneurysms in individuals with and without type 2 diabetes. METHODS: Using spectral domain optical coherence tomography (OCT), we performed a macular volume scan in 2647 individuals (mean age 60 ± 8 years, 50% men, 27% type 2 diabetes). The association between macular cysts and 24-hour systolic and diastolic blood pressure, pulse pressure, mean arterial blood pressure, carotid-femoral pulse wave velocity and carotid distensibility was assessed by use of logistic regression. RESULTS: Twenty-four hours systolic blood pressure was associated with the presence of macular cysts [OR = 1.03 (95% CI 1.00-1.05) per 1 mmHg, p = 0.03]. 24 hr pulse pressure [OR = 1.61 (95% CI 1.11-2.34) per 10 mmHg, p = 0.01] and carotid-femoral pulse wave velocity [OR = 1.16 (95% CI 1.02-1.32) per 1 m/s, p = 0.02] were associated with macular cysts, while carotid distensibility was not [OR = 1.03 (95% CI 0.96-1.11) per 1.0*10-3 /kPa, p = 0.45]. Associations were similar in individuals with and without type 2 diabetes and were already present in the absence of micro-aneurysms. CONCLUSION: Twenty-four hours systolic blood pressure, 24 hr pulse pressure and carotid-femoral pulse wave velocity are associated with the presence of OCT-detected macular cysts in individuals with and without type 2 diabetes, even in the absence of micro-aneurysms. Therefore, blood pressure and aortic stiffness are potential factors contributing to macular cysts.

Prevalence of optical coherence tomography detected vitreomacular interface disorders: The Maastricht Study.

PURPOSE: To calculate the prevalence of all vitreomacular interface (VMI) disorders and stratify according to age, sex and (pre)diabetes status. METHODS: The presence of VMI disorders was assessed in 2660 participants aged between 40 and 75 years from The Maastricht Study who had a gradable macular spectral-domain optical coherence tomography (SD-OCT) volume scan in at least one eye [mean 59.7 ± 8.2 years, 50.2% men, 1531 normal glucose metabolism (NGM), 401 prediabetes, 728 type 2 diabetes (DM2, oversampled)]. A stratified and multivariable logistic regression analysis was used. RESULTS: The prevalence of the different VMI disorders for individuals with NGM, prediabetes and DM2 was, respectively, 5.7%, 6% and 6.7% for epiretinal membranes; 6%, 9.6% and 6.8% for vitreomacular traction; 1.1%, 0.7% and 0.3% for lamellar macular holes; 0.1%, 0% and 0% for pseudoholes; 1.1%, 1.9% and 5.5% for macular cysts. None of the participants was diagnosed with a macular hole. The prevalence of epiretinal membranes, vitreomacular traction and macular cysts was higher with age (p < 0.001). Vitreomacular traction and lamellar macular holes were more frequent in women (p < 0.01). DM2 is positively associated [OR = 3.9 (95% CI 2.11-7.22, p < 0.001)] with macular cysts and negatively associated with lamellar macular holes [OR = 0.2 (95% CI 0.04-0.9, p = 0.036)] after adjustment for age and sex. The calculated prevalence of VMI disorders was 15.9%. CONCLUSIONS: The calculated prevalence of VMI disorders in individuals aged between 40 and 75 years is 15.9%. The prevalence depends on age, sex and glucose metabolism status for several types of VMI disorders.

Macular thinning in prediabetes or type 2 diabetes without diabetic retinopathy: the Maastricht Study.

PURPOSE: To assess macular thinning in individuals with prediabetes or type 2 diabetes without diabetic retinopathy (DM2 w/o DR) compared with individuals with normal glucose metabolism (NGM). METHODS: Using spectral domain optical coherence tomography (SD-OCT), we measured macular thickness in six subfields as defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) in 1838 participants from The Maastricht Study, a population-based cohort study (mean age 59 ± 8 years, 49% men, 1087 NGM, 279 prediabetes, 472 DM2 w/o DR). Multivariable linear regression was used to assess the association between macular thickness and glucose metabolism status. RESULTS: After adjustment for age, sex and spherical equivalent, individuals with prediabetes showed a significant decrease in pericentral superior macular thickness [ß = -2.14 µm (95% confidence interval (CI): -4.24 to -0.03), p < 0.05] compared with individuals with NGM. In individuals with DM2 w/o DR, the fovea [ß = -4.05 µm (95% CI: -6.30 to -1.79), p < 0.001] and the four pericentral quadrants (range: ß = -4.64 to -5.29 µm, p < 0.001) were significantly thinner compared with individuals with NGM. There was a significant linear trend of macular thinning with severity of glucose metabolism status in five subfields (p < 0.001). CONCLUSION: Macular thickness is reduced in prediabetes and a greater reduction occurs in DM2, even before DR is clinically present. About half of the thinning observed in DM2 w/o DR was already found in prediabetes. Generalized thinning of the macula could be related to thinning of the temporal side of the optic nerve head through the connecting papillo-macular bundle.

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 × 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.

Diplopia was not predictable and not associated with buckle position after scleral buckling surgery for retinal detachment.

PURPOSE: The possibility of postoperative binocular diplopia is seen as an important drawback of conventional scleral buckling surgery for rhegmatogenous retinal detachment. The goal of this study was to evaluate the occurrence and pattern of binocular diplopia after scleral buckle procedures in patients with rhegmatogenous retinal detachment. METHODS: In a retrospective study of 1,030 patients with primary rhegmatogenous retinal detachment who were treated by scleral buckle surgery between January 2001 and July 2008, the postoperative occurrence of binocular diplopia was retrieved from the medical charts. RESULTS: Secondary strabismus developed in 39 subjects (3.8%) after scleral buckle surgery during a mean follow-up of 6.4 ± 6.3 months. Twenty-eight patients (2.7%) developed strabismus because of a mechanical restriction of one of the muscles. No association was found between the position of the buckle, that is, the muscle affected, and the incidence of diplopia. A moderate significant association was found when two muscles were affected with a higher incidence of diplopia. This was, however, not found for three or more muscles. In 28 of 39 patients, binocular single vision was restored at the end of the follow-up period. In the majority, this was accomplished with conventional prism treatment. CONCLUSION: Strabismus caused by a restriction of the muscles in scleral buckle surgery was not predictable based upon the buckle position. Patients with a minimal restriction of the muscles after scleral buckle surgery can often be well treated with prisms.

Persistent subfoveal fluid and increased preoperative foveal thickness impair visual outcome after macula-off retinal detachment repair.

PURPOSE: To investigate the influence of subfoveal fluid and foveal thickness on visual outcome in patients who underwent reattachment surgery for rhegmatogenous retinal detachment (RRD). METHODS: This prospective study included 53 patients who were undergoing successful scleral buckling surgery for primary RRD. A thorough ophthalmologic examination including best-corrected visual acuity, slit-lamp biomicroscopy, binocular indirect ophthalmoscopy, and optical coherence tomography scanning was performed preoperatively and during all subsequent follow-up visits at 1, 3, 6, 9, 12, and 24 months postoperatively. RESULTS: Preoperative foveal thickness was significantly higher in the macula-off group (n = 38) compared with the macula-on group (n = 15) (P < 0.0001), whereas postoperative measurements were normal in both the groups. Linear mixed-model analysis revealed that persistent subfoveal fluid (P = 0.0004) was an independent predictor of a worse visual outcome after scleral buckling surgery for primary macula-off RRD, although the effect on visual outcome was small (0.1 logarithm of the minimal angle of resolution units). Moreover, increased preoperative foveal thickness was associated with a worse visual prognosis in macula-off RRD (P = 0.010). CONCLUSION: Persistent subfoveal fluid and increased preoperative foveal thickness were associated with a worse visual prognosis in macula-off RRD patients, albeit the effect of persistent subfoveal fluid was small and temporary.

Soluble apoptotic factors and adhesion molecules in rhegmatogenous retinal detachment.

PURPOSE: To investigate the association between soluble apoptosis and adhesion molecules and the development of proliferative vitreoretinopathy (PVR) after reattachment surgery for rhegmatogenous retinal detachment (RRD). METHODS: A multiplex immunoassay was used to measure soluble Fas (sFas), sFas ligand (sFasL), soluble intercellular adhesion molecule (sICAM)-1, and soluble vascular cell adhesion molecule (sVCAM)-1 levels in 55 subretinal fluid samples collected during scleral buckling surgery for primary RRD. Seventeen patients who developed a redetachment due to postoperative PVR after reattachment surgery (PVR group) were compared with age-, sex-, and storage-time-matched RRD samples from 38 patients with an uncomplicated postoperative course (RRD group). Ten vitreous samples from patients with macular hole and ten vitreous samples from eye bank eyes served as additional controls. RESULTS: A 2- to 3-fold increase in levels of sFas, sFasL, sICAM-1, and sVCAM-1 was found in the PVR group compared with those of the RRD group (P < 0.05 for all analytes), as well as a 5- to 20-fold increase in the PVR group compared with those of additional control groups (P < 0.001 for all analytes). Significant associations (P < 0.001) were found between sFas and both sICAM-1 (r = 0.84) and sVCAM-1 (r = 0.93) and between sFasL and both sICAM-1 (r = 0.82) and sVCAM-1 (r = 0.85). In addition, sFas, sFasL, and sVCAM-1 were significantly correlated (P < 0.05) with the extent and duration of retinal detachment. CONCLUSIONS: These findings indicate that an increased expression of soluble apoptosis and adhesion molecules at the time of primary retinal detachment surgery is associated with the future development of PVR.

Anterior chamber depth is significantly decreased after scleral buckling surgery.

OBJECTIVE: Myopic patients have an increased risk for the development of a rhegmatogenous retinal detachment (RRD). Currently, myopic patients have the choice to undergo correction of their refractive error by the implantation of a phakic intraocular lens (pIOL). After pIOL implantation, progressive endothelial cell loss may result if the anterior chamber is too shallow. Because scleral buckling (SB) surgery for treatment of an RRD may in itself result in a decreased anterior chamber depth (ACD), this may become an important issue not only for the retinal surgeon who is faced with a patient who has both an RRD and a pIOL, but also for the refractive surgeon who should consider the potential problems of the implantation of pIOL in an eye that has previously undergone SB surgery. The goal of this study was to evaluate how long changes in ACD persist after SB procedures in patients with RRD. DESIGN: Prospective case series. PARTICIPANTS: Thirty-eight eyes with a primary RRD treated by SB using an encircling element and a radial or segmental buckle; 31 fellow eyes served as controls. METHODS: Anterior chamber depth (in the horizontal meridian) and axial length were measured preoperatively and at 1 week and 1, 3, 6, 9, and 12 months postoperatively with an anterior optical coherence tomography method and an IOLMaster (Carl Zeiss Meditec, Jena, Germany), respectively. MAIN OUTCOME MEASURES: In all 38 eyes, ACD was significantly reduced compared with preoperative levels up to 9 months after SB surgery. RESULTS: Anterior chamber depth returned to normal at 1 year after surgery. Axial length was significantly enlarged during the whole follow-up period. No significant differences were found between the use of radial or segmental buckles. CONCLUSIONS: Anterior chamber depth may remain decreased after SB for a longer time period than previously reported. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

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.

Scleral buckling surgery after macula-off retinal detachment: worse visual outcome after more than 6 days.

PURPOSE: To determine the effect of duration of macular detachment (DMD) on visual acuity (VA) in patients with macula-off rhegmatogenous retinal detachment (RD). DESIGN: Retrospective observational case series. PARTICIPANTS: Two hundred two consecutive patients (202 eyes) with primary uncomplicated macula-off RD, preoperative VA of 10/100 or worse, a precise history of when macular function was lost, successful reattachment surgery, and a minimal follow-up of 3 months. INTERVENTION: All RDs were repaired with a primary scleral buckling procedure performed by 3 vitreoretinal surgeons. MAIN OUTCOME MEASURE: Visual acuity (best corrected and 3, 6, and 12 months postoperatively). RESULTS: Considering all eyes, the cumulative mean of the best-corrected postoperative VA (logarithm of the minimum angle of resolution [logMAR]) as a function of DMD shows a rapid worsening when DMD exceeds 6 days. Eyes were divided into 3 groups, corresponding to the DMD intervals immediate (within 10 days), delayed (11 days-6 weeks), and late (>6 weeks). Mean postoperative VAs (in logMAR) were 0.35+/-0.31 (between 20/40 and 20/50 Snellen equivalent) in eyes with DMD up to 10 days, 0.48+/-0.26 (20/60 Snellen equivalent) in the delayed group, and 0.86+/-0.30 (8/60 Snellen equivalent) in eyes with DMD longer than 6 weeks. CONCLUSIONS: The cumulative mean of the best-corrected postoperative VA (logMAR) as a function of DMD shows a rapid worsening when DMD exceeds 6 days. Our results indicate that the scleral buckling procedure should be done preferably within a 7-day DMD.