Ultrasound biomicroscopy of the equine iridocorneal angle.

BACKGROUND: The iridocorneal angle (ICA) is the major pathway of aqueous humour outflow from the anterior chamber of the eye. Ultrasound biomicroscopy (UBM) has been utilised to characterise the morphology of this drainage pathway in numerous species. UBM may allow for early recognition of aqueous humour outflow obstructions in horses, allowing for earlier recognition of risk for glaucoma, a vision-threatening and painful disease. UBM morphology of the normal equine ICA has yet to be described. OBJECTIVES: To determine the ultrasonographic morphology of the equine ICA by UBM in standing sedated horses. STUDY DESIGN: In vivo experimental study. METHODS: Thirty healthy adult horses underwent UBM of the ICA at four locations (superior, temporal, inferior, nasal) of each eye utilising standing sedation, topical anaesthesia and auriculopalpebral perineural anaesthesia. Anatomic structures were defined on ultrasound images through comparison to published histologic photomicrographs of the equine ICA. RESULTS: Ultrasound imaging of the ICA at all four locations was easily performed in standing, sedated horses. High-resolution images of the ICA allowed for identification of the pectinate ligament, corneoscleral trabecular meshwork (TM), uveal TM and supraciliary TM. MAIN LIMITATIONS: Pupil size was midrange in all eyes, but was not strictly controlled. Lighting conditions not controlled. Various breeds included. CONCLUSION: In vivo UBM of the equine ICA is feasible and provides high-resolution images of the structures of the aqueous humour outflow pathway.

Reliability of Aqueous Flare Measurements During Uveitis by a Spot Fluorometer.

Purpose: To evaluate the reliability of intensity of light scatter (ILS) for diagnosing mild-to-moderate uveitis, which is difficult to score by the subjective standardized uveitis nomenclature (SUN) grading. Methods: ILS (in millivolts) was measured in healthy subjects and uveitis patients by a custom-made Spot fluorometer. The reliability was assessed by noise analysis of the instrument using turbid samples and intra- and interobserver variabilities. Results: ILS increased with the severity of inflammation: healthy (0.1498 ± 0.0564) and SUN0 (0.1590 ± 0.0564) < SUN1+ (0.2050 ± 0.0887) < SUN2+ (0.4283 ± 0.1895). The increase in ILS was more significant between healthy and SUN1+ (P < 0.0001) compared to the difference between SUN0 and SUN1+ (P = 0.0006). The instrument noise was small (σ = 0.002). Intraobserver measurements revealed no variability (P > 0.98) between measurements and predicted repeatability coefficients of 0.0754, 0.0522, and 0.0532 in healthy, SUN0, and SUN1+, respectively. Interobserver measurements also showed no variability (P > 0.88) and predicted intraclass correlation coefficient > 0.63 in healthy and uveitis subjects. Conclusions: The fluorometer enables precise measurement of ILS with negligible instrument noise, and the measurements are unaffected by intra- and interobserver variabilities. However, the difference in mean ILS between SUN0 and SUN1+ is greater than the instrument noise and comparable to intra- and interobserver variabilities. Thus, ILS measurements are likely impacted by blinking, eye movements, and focusing jitter. The impact of these factors must be reduced before using the fluorometer to distinguish mild-to-moderate uveitis.

Analysis of cytokines in the aqueous humor during intravitreal Ranibizumab treatment of diabetic macular edema.

This study aimed to analyze the concentrations of VEGF, b-FGF, TNF, interleukin (IL)-1, IL-6, IL-8, IL-10, and IL-12 in the aqueous humor of patients with diabetic macular edema with and without peripheral retinal ischemia and to ascertain the changes in the levels of these molecules during treatment with ranibizumab. A therapeutic, prospective, randomized interventional study was carried out. Twenty-four eyes from 24 patients were studied and divided into 3 groups. Group 1 (9 eyes) included patients with diabetic macular edema without peripheral ischemia. Group 2 (10 eyes) included patients with diabetic macular edema with peripheral ischemia. Group 3 (5 eyes), the control group, included patients without systemic and/or eye diseases. Patients in Groups 1 and 2 received 3 intravitreal injections of 2 mg/0.05 ml ranibizumab at an interval of approximately 30 days. Before administering the injections, the aqueous humor was collected. In the control group, aqueous humor was collected before facetectomy. During treatment, the median IL-6 concentration significantly increased in Group 1 but showed a slight but not significant decrease in Group 2. Interleukin 8 levels were significantly different at the end of treatment compared to the beginning in Groups 1 and 2. TNF, IL-1, IL-10, and IL-12 levels were practically unchanged in both groups. VEGF was significantly reduced at the end of the study in Groups 1 and 2. B-FGF was not detected in most of the studied patients, and in those with detectable levels, there was no significant variation. There was a significant increase in the median level of interleukin 6 in the group without ischemia and a significant decrease in VEGF in both groups. The cytokines TNF, IL-1, IL-10, and IL-12 did not show significant variation.

Association between Inflammatory Factors in the Aqueous Humor and Hyperreflective Foci in Patients with Intractable Macular Edema Treated with Antivascular Endothelial Growth Factor.

BACKGROUND: To evaluate the correlations between the inflammatory factors in the aqueous humor and hyperreflective foci (HRF) in patients with intractable macular edema treated with antivascular endothelial growth factor (anti-VEGF). METHODS: This study included 17 patients with intractable macular edema (ME) treated with anti-VEGF agents. Inflammatory factors in the aqueous humor were measured by the Cytometric Beads Array before injection, and the numbers of HRF pre- and post-anti-VEGF treatment were counted from four different directions (90 degrees, 45 degrees, 180 degrees, and 135 degrees) in the SD-OCT images, respectively, before treatment and one month after treatment. The correlations between inflammatory factors and the numbers of HRF were assessed. RESULTS: The numbers of HRF were reduced significantly after anti-VEGF treatment. The change in the HRFs at the 90-degree location was significantly positively correlated with IL-8 and VCAM-1. The change of all HRFs was significantly positively correlated with IL-8. The HRFs before the treatment also had a positive correlation with IL-8 and VCAM-1. CONCLUSION: After anti-VEGF treatment, the numbers of HRF in intractable ME declined greatly. The higher the levels of IL-8 and VCAM-1 before treatment, the more significant the reduction of HRF after anti-VEGF treatment, which indicated that HRF could be an effective noninvasive imaging indicator for evaluating the effect of anti-VEGF on intractable macular edema. The OCT images at the 90-degree location could better show the inflammatory reaction of patients and also had better clinical significance for the prognosis evaluation of ME associated with inflammation.

Early Onset of Age-Related Cataracts in Cystine/Glutamate Antiporter Knockout Mice.

Purpose: The purpose of this study was to determine the importance of the xCT is a subunit. The cystine/glutamate antiporter is actually system xc-xCT subunit of the cystine/glutamate antiporter in maintaining redox balance by investigating the effects of the loss of xCT on lens transparency and cystine/cysteine balance in the aqueous humour. Methods: C57Bl/6 wild-type and xCT knockout mice at five age groups (6 weeks to 12 months) were used. Lens transparency was examined using a slit-lamp and morphological changes visualized by immunolabelling and confocal microscopy. Quantification of glutathione in lenses and cysteine and cystine levels in the aqueous was conducted by liquid chromatography tandem mass spectrometry (LC-MS/MS). Results: Slit-lamp examinations revealed that 3-month-old wild-type mice and xCT knockout mice lenses exhibited an anterior localized cataract. The frequency of this cataract significantly increased in the knockout mice compared to the wild-type mice. Morphological studies revealed a localized swelling of the lens fiber cells at the anterior pole. Glutathione levels in whole lenses were similar between wild-type and knockout mice. However, glutathione levels were significantly decreased at 3 months in the knockout mice in the lens epithelium compared to the wild-type mice. Aqueous cysteine levels remained similar between wild-type and knockout mice at all age groups, whereas cystine levels were significantly increased in 3-, 9-, and 12-month-old knockout mice compared to wild-type mice. Conclusions: Loss of xCT resulted in the depletion of glutathione in the epithelium and an oxidative shift in the cysteine/cystine ratio of the aqueous. Together, these oxidative changes may contribute to the accelerated development of an anterior cataract in knockout mice, which appears to be a normal feature of aging in wild-type mice.

In-vivo imaging of the conventional aqueous outflow system.

PURPOSE OF REVIEW: The aim of this study was to provide a comprehensive summary of in-vivo imaging techniques of the aqueous outflow system and discuss its role in improving our understanding of glaucoma pathogenesis and management. RECENT FINDINGS: Our understanding of the aqueous outflow system is largely derived from ex-vivo studies. Recent innovations in imaging technology and techniques enable in-vivo evaluation of the conventional outflow system in real-time. Optical coherence tomography allows for noninvasive, high-resolution, volumetric imaging of ocular tissues. Dynamic structural changes have been observed at the trabecular meshwork and Schlemm's canal. In parallel, aqueous angiography using injected tracers show a similar dynamism with variable and pulsatile flow signals. SUMMARY: In-vivo imaging enable real-time evaluation of the conventional aqueous outflow pathway. This emerging field shows great promise to expand our understanding of the pathogenesis and treatment of glaucoma.

Role of Inflammation in Retinal Microcirculation in Diabetic Eyes: Correlation between Aqueous Flare and Microvascular Findings.

PURPOSE: To investigate the correlation between aqueous flare and macular microvascular status assessed by optic coherence tomography angiography (OCTA) in diabetes mellitus. METHODS: A cross-sectional study was conducted on 52 diabetic patients with nonproliferative retinopathy, 44 diabetic patients without retinopathy, and 20 nondiabetic age-matched controls. Spectral domain OCT, OCTA, and laser flare-cell meter were performed. RESULTS: Compared to eyes without retinopathy, eyes with retinopathy had higher flare intensity (p = 0.024), enlarged capillary nonperfusion area (p < 0.001), and enlarged foveal avascular zone (p < 0.001). There was a significant correlation between flare intensity and capillary nonperfusion areas (p < 0.001, r = 0.511) and superficial capillary density (p = 0.005, r = -0.388) in diabetic eyes with retinopathy. CONCLUSION: The results demonstrated a positive correlation between aqueous flare levels, an indicator of intraocular inflammation, and microvascular damage demonstrated by OCTA in the early stages of diabetic retinopathy (DR). This finding supports the role of inflammation in the pathogenesis of DR.

Evaluation of choroidal thickness, macular thickness, and aqueous flare after cataract surgery in patients with and without diabetes: a prospective randomized study.

BACKGROUND: In diabetic eyes, various choroidal abnormalities are noted in addition to changes in the retinal circulation, and the risk of increased aqueous flare and retinal thickening after cataract surgery is higher in diabetic eyes. Inflammation caused by surgery induces breakdown of the blood-retinal barrier and affects the retina, although the influence on the choroid is unknown. Several researchers have evaluated the choroidal thickness (CT) after cataract surgery in patients with diabetes; however, the results are inconsistent. The purpose of this study was to evaluate the influence of uneventful small-incision phacoemulsification cataract surgery on the subfoveal choroidal thickness (SCT), the central macular thickness (CMT), and aqueous flare in patients with diabetes. METHODS: This study included 59 randomly selected eyes (33 eyes of patients with diabetes and 26 eyes of control patients without diabetes) undergoing small-incision cataract surgery. Among the diabetic eyes, 26 were without diabetic retinopathy, and the remaining eyes had non-proliferative diabetic retinopathy. Aqueous flare, CMT, and SCT measurements were performed before and at 1 week, 1 month, and 3 months after surgery. RESULTS: The postoperative CMT continued to increase significantly until 3 months in both groups. Although the CMT was more in patients with diabetes than in patients without diabetes during the follow-up period, there was no significant difference between the two groups. The aqueous flare value increased until 3 months after surgery in both groups. Although the increase was significant at 3 months after surgery in patients with diabetes, the increase in controls was not significant. The aqueous flare values differed significantly between the two groups before and at 3 months after surgery. There was no significant within-group or between-group difference in pre- and postoperative SCT values. CONCLUSION: In diabetic eyes with early stage of retinopathy, even small-incision cataract surgery can induce increased aqueous flare and macular thickening until 3 months, although there is no significant change in the choroidal thickness. Further studies are essential to evaluate choroidal changes after the cataract surgery in diabetic eyes.

Correlation between anterior chamber flare changes and diabetic macular edema after intravitreal injection of ranibizumab and aflibercept.

PURPOSE: To evaluate aqueous flare change patterns following anti-vascular endothelial growth factor therapy for diabetic macular edema (DME) and investigate the relationship between changes in flare values and central macular thickness (CMT). STUDY DESIGN: Retrospective, interventional case series METHODS: A total of 84 eyes of 62 patients with DME received either intravitreal ranibizumab (IVR; n = 62) or aflibercept (IVA; n = 22). A laser flare photometer (Kowa FM500, Kowa Company, Ltd) was used to measure flare values, and CMT was assessed using optical coherence tomography. Flare values and CMT were measured prior to injection (baseline) and at, 1, 7 and 14 days after injection. RESULTS: Flare values in the IVR group decreased significantly at day 14 (P = 0.001), whereas the IVA group showed a significant increase in flare values at day 1 (P < 0.001). In the IVA group, the baseline flare values were significantly higher in the CMT reduction group than in the non-CMT reduction group (P = 0.035). There was no correlation between changes in flare values and CMT either in the IVA or IVR group. CONCLUSIONS: Flare value changes in patients treated with IVR decreased at day 14 post-injection. This may indicate when the most anti-inflammatory effect was obtained. There was no correlation between changes in flare values and CMT either in the IVA or IVR group; nevertheless, our research suggests that the baseline flare value is a predictive factor for the efficacy of IVA in DME.

Intraocular infiltration of Philadelphia chromosome-positive acute lymphoblastic leukemia diagnosed by polymerase chain reaction from the aqueous humor: A case report.

RATIONALE: Intraocular manifestation of hematopoietic tumors is rare and often difficult to distinguish from inflammation. We report a patient with acute lymphoblastic leukemia (ALL) who developed intraocular infiltration during the remission period. PATIENT CONCERNS: A 40-year-old man presented with hypopyon in his right eye. Three months later, extensive subretinal infiltration and the elevation of intraocular pressure were observed. Fourteen months prior to this, he had been diagnosed with Philadelphia chromosome-positive ALL, and had received chemotherapy and bone marrow transplantation that resulted in complete remission. DIAGNOSIS: The breakpoint cluster region-Ableson (BCR/ABL) chimera was detected by polymerase chain reaction (PCR) analysis in the patient's aqueous humor. Additionally, a high expression of WT1 (Wilms tumor gene) mRNA in the aqueous humor was discovered. A bone marrow examination yielded a high expression of BCR/ABL fusion gene, and it was determined the patient had experienced a relapse of ALL. INTERVENTIONS: The dasatinib was administered orally to the patient. OUTCOMES: The intraocular infiltration disappeared, and intraocular pressure was normalized. LESSONS: Intraocular infiltration in leukemia patients may be an indication of relapse regardless of systemic conditions. Analyzing mRNA expression of BCR/ABL and WT1 of ocular fluid in patients with hypopyon is beneficial in diagnosing topical relapses in leukemia.

Detection of small molecule concentration gradients in ocular tissues and humours.

The eye is an elegant organ consisting of a number of tissues and fluids with specialised functions that together allow it to effectively transmit and transduce light input to the brain for visual perception. One key determinant of this integrated function is the spatial relationship of ocular tissues. Biomolecular distributions within the main ocular tissues cornea, lens, and retina have been studied extensively in isolation, yet the potential for metabolic communication between ocular tissues via the ocular humours has been difficult to visualise. To address this limitation, the current study presents a method to map spatial distributions of metabolites and small molecules in whole eyes, including ocular humours. Using a tape-transfer system and freeze-drying, the spatial distribution of ocular small molecules was investigated in mouse, rat, fish (black bream), and rabbit eyes using negative ion mode MALDI imaging mass spectrometry. Full-scan imaging was used for discovery experiments, while MS/MS imaging for identification and localisation was also demonstrated. In all eyes, metabolites such as glutathione and phospholipids were localised in the main ocular tissues. In addition, in rodent eyes, major metabolites were distributed relatively uniformly in ocular humours. In contrast, both uniform and spatially defined ocular metabolite distributions were observed in the black bream eye. Tissue and ocular humour distributions were reproducible, as demonstrated by the three-dimensional analysis of a mouse eye, and able to be captured with high spatial resolution analysis. The presented method could be used to further investigate the role of inter-tissue metabolism in ocular health, and to support the development of therapeutics to treat major ocular diseases.

Alzheimer's Disease and Retinal Degeneration: A Glimpse at Essential Trace Metals in Ocular Fluids and Tissues.

BACKGROUND: Life expectancy is increasing all over the world, although neurodegenerative disorders might drastically affect the individual activity of aged people. Of those, Alzheimer's Disease (AD) is one of the most social-cost age-linked diseases of industrialized countries. To date, retinal diseases seem to be more common in the developing world and characterize principally aged people. Agerelated Macular Degeneration (AMD) is a late-onset, neurodegenerative retinal disease that shares several clinical and pathological features with AD, including stress stimuli such as oxidative stress, inflammation and amyloid formations. METHODS: In both diseases, the detrimental intra/extra-cellular deposits have many similarities. Aging, hypercholesterolemia, hypertension, obesity, arteriosclerosis and smoking are risk factors to develop both diseases. Cellular aging routes have similar organelle and signaling patterns in retina and brain. The possibility to find out new research strategies represent a step forward to disclose potential treatment for both of them. Essential trace metals play critical roles in both physiological and pathological condition of retina, optic nerve and brain, by influencing metabolic processes chiefly upon complex multifactorial pathogenesis. CONCLUSION: Hence, this review addresses current knowledge about some up-to-date investigated essential trace metals associated with AD and AMD. Changes in the levels of systemic and ocular fluid essential metals might reflect the early stages of AMD, possibly disclosing neurodegeneration pathways shared with AD, which might open to potential early detection.

Clinical factors contributing to postoperative aqueous flare intensity after 27-gauge pars plana vitrectomy for the primary rhegmatogenous retinal detachment.

PURPOSE: To investigate the perioperative clinical factors, which contribute to the postsurgical aqueous flare intensity (AFI) following 27-gauge pars plana vitrectomy (27GPPV) for primary rhegmatogenous retinal detachment (RRD). STUDY DESIGN: Retrospective clinical study. METHODS: We performed retrospective analyses of the medical records of 47 eyes of 47 patients with primary RRD who had undergone 27GPPV with a wide-angle viewing system. AFI was measured preoperatively and 1 week, 1 month, 3 months, 6 months, and 12 months after the surgery. RESULTS: AFI was significantly increased 1 week after the surgery (p<0.01) and then decreased overtime. At 6 months after surgery it was still statistically significantly higher than preoperative AFI (p=0.03). There was no statistical difference between preoperative AFI and that at 12 months following surgery. Multiple regression analyses revealed that the number of retinal photocoagulations and the performance of scleral indentation had significant positive correlation with AFI at 1 week, 1 month, 3 months, and 6 months, and at 1 month and 3 months after the surgery, respectively. CONCLUSION: Intraoperative retinal photocoagulation and scleral indentation are probable causes of increased AFI after 27G PPV for RRD.

Age-related changes in eye morphology and aqueous humor dynamics in DBA/2J mice using contrast-enhanced ocular MRI.

PURPOSE: Here, we are testing the hypothesis that dynamic contrast enhanced MRI (DCE-MRI) is a useful approach for non-invasively evaluating age-related changes in aqueous humor outflow and its contribution to elevated intraocular pressure in the DBA/2J model of pigmentary glaucoma. METHODS: A rodent-specific 7 T MRI was used to assess eye anatomy (anterior chamber (AC) and vitreous body (VB) morphology, eye size, lens size) and aqueous humor dynamics (via intravenous administration of Gd-DTPA and Gd-BOPTA contrast agents) in C57BL/6 and DBA/2J mice at 3 and 9 months of age. RESULTS: Gd-MRI was used to demonstrate an anterior solute pathway into the mouse AC. Topical latanoprost treatment in C57BL/6J mice reduced Gd-BOPTA accumulation in the AC. Age-related increases in AC area, AC depth and eye size were observed in DBA/2J mice compared to C57BL/6J mice. The rate of Gd-DTPA accumulation and peak Gd-DTPA intensity was lowest in 9-month old DBA/2J mice compared to 3-month old DBA/2J mice and C57BL/6J mice at both ages. Leakage of Gd-DTPA posteriorly into the VB was also observed in 9-month old DBA/2J mice. CONCLUSIONS: These studies support the idea that age-related changes in aqueous humor outflow contribute to elevated intraocular pressure (IOP) in the DBA/2J model of pigmentary glaucoma. Gd-MRI is a valuable tool for better understanding of mechanisms and dynamics of aqueous humor circulation in normal and glaucomatous mouse eyes or following topical administration of medicines to reduce IOP.

Correlation between aqueous flare and residual visual field area in retinitis pigmentosa.

BACKGROUND/AIMS: To investigate the relationship between aqueous flare, visual function and macular structures in retinitis pigmentosa (RP). METHODS: Clinical data from 123 patients with RP (227 eyes), 35 patients with macular dystrophy (68 eyes) and 148 controls (148 eyes) were analysed. The differences in aqueous flare between clinical entities and the correlation between aqueous flare (measured with a laser flare cell meter) versus visual acuity, visual field area (Goldmann perimetry) and macular thickness (optical coherence tomography) in patients with RP were determined. Influence of selected clinical data on flare was assessed using linear mixed-effects model. RESULTS: Aqueous flare was higher in patients with RP than patients with macular dystrophy or controls (p=7.49×E-13). Aqueous flare was correlated with visual field area (R=-0.379, p=3.72×E-9), but not with visual acuity (R=0.083, p=0.215). Macular thickness (R=0.234, p=3.74×E-4), but not foveal thickness (R=0.122, p=0.067), was positively correlated with flare. Flare was not affected by the presence of macular complications. All these associations were maintained when the right and the left eyes were assessed separately. Analysis by linear mixed-effects model revealed that age (p=8.58×E-5), visual field area (p=8.01×E-7) and average macular thickness (p=0.037) were correlated with flare. CONCLUSION: Aqueous flare and visual field area were correlated in patients with RP. Aqueous flare may reflect the degree of overall retinal degeneration more closely than the local foveal impairment.

Application of Laser Flare Photometry in the Quantification of Blood-Aqueous Barrier Breakdown after Micro-incision Vitrectomy.

Purpose: The purpose of the study is to quantify aqueous flare using laser flare photometry (LFM) in patients undergoing 25-G pars plana vitrectomy (PPV) and assess the need for postoperative topical corticosteroid administration . Methods: Prospective evaluation of 50 eyes (50 patients) was performed using LFM until day 30 postoperative. Duration of surgery, indication of PPV, and use of laser and/or cryotherapy were noted. Topical corticosteroids were used if mean LFM values were >50, or if there was anterior chamber fibrin. Results: Mean age of the subjects was 48.62 ± 10.07 years. The preoperative LFM value for 50 subjects was 17.42 ± 25.20. Topical corticosteroids were initiated in only 22 patients. The LFM values of subjects were not different from baseline at 1 month whether or not the subjects received corticosteroids (p > 0.106). Conclusions: With 25-G PPV, there is minimal breakdown of blood-aqueous barrier. LFM helps in monitoring postoperative inflammation, obviating the need for topical corticosteroids in significant number of patients.

Relationship between aqueous humor cytokine level changes and retinal vascular changes after intravitreal aflibercept for diabetic macular edema.

The aim of this work was to investigate the changes in aqueous humor cytokine levels after intravitreal injection of aflibercept in diabetic macular edema (DME) and to evaluate the relationship between cytokines modifications and central macular thickness (CMT) and retinal/choroidal vascular changes using structural and functional optical coherence tomography (OCT). Aqueous concentrations of 38 cytokines were measured via multiplex bead assay. In addition, spectral domain OCT and OCT angiography with SSADA software (XR Avanti® AngioVue) were performed at baseline and after intravitreal injections. VEGF, IL-6, IL-5, IL-1ß, Eotaxin, GRO, IL-12p40, IL-12p70, IL-1RA, Flt-3L and IP-10 showed a statistically significant decrease through the follow-up (p < 0.05; p < 0.001), while Fraktalkine and GM-CSF significantly increased (p < 0.05). Best corrected visual acuity significantly increased and CMT significantly decreased during follow-up (p < 0.001 and p = 0.013). Superficial capillary plexus and deep capillary plexus density significantly increased (p < 0.001 and p = 0.014). A positive relation was found between GRO, VEGF, Fraktalkine, IP-10, IL-12p70 aqueous humor levels and CMT (p < 0.05; p < 0.001). Aflibercept is a primary anti-VEGF treatment producing a decrease of DME due to the reduction of vascular permeability, nevertheless other inflammatory cytokines showed modification after aflibercept intravitreal injections probably related to edema modification or to an interaction of aflibercept with other inflammatory cytokines.

Clinical features of infectious posterior segment uveitis.

OBJECTIVE: To assess the clinical findings and microbiology investigations in patients with suspected infectious posterior segment uveitis (PSU). DESIGN: Retrospective case study. METHODS: Between January and December 2014, medical records of 270 patients with PSU were reviewed. Baseline ocular examination, presumed and final diagnoses, microbiology investigations from aqueous or vitreous fluid, and peripheral blood were reviewed. RESULTS: Infectious PSU was suspected in 28 patients among 270 PSU cases (10.4%, 28/270), and 11 cases were of infectious origin (4.1%, 11/270). Six patients were immunocompromised: 5 patients in the confirmed infectious PSU group (45.5%, 5/11) and 1 in the confirmed noninfectious group (5.9%, 1/17; p = 0.002). Initial visual acuity was 1.8 ± 0.35 logMAR and 0.9 ± 0.23 logMAR for patients with confirmed infectious and noninfectious PSU, respectively (p = 0.04). Anterior chamber reaction was worse in patients with confirmed infectious PSU (1.8 ± 0.49) than confirmed noninfectious cases (0.5 ± 0.1; p = 0.003). The frequency of chorioretinitis among patients with confirmed infectious and noninfectious PSU is 54.5% (6/11) and 11.8% (2/17; p = 0.03), respectively. Onset of confirmed infectious uveitis was more acute (≤6 weeks in duration) than noninfectious cases (p = 0.0015). Among the 11 patients with positive blood culture or serology, 6 had anterior and vitreous chamber fluid analysis. The rate of positive cultures and PCR is 16.7% (1/6) for aqueous humour and 50% (3/6) for vitreous samples. CONCLUSIONS: Clinical features more suggestive of infectious PSU include immunosuppression, worse initial visual acuity, acute onset, worse anterior chamber reaction, and chorioretinitis. Further studies are needed to enhance the diagnostic yields of aqueous and vitreous fluid analyses.