Lower Conjunctival Sac Research Articles

Human ocular thelaziosis—a zoonosis of the eye

A 36-year-old man presented to the ophthalmology department with a 1-month history of redness in his right eye, photophobia, and tearing and foreign body sensation without improvement, despite antibiotics and topical treatment with corticosteroid at the regional hospital. The right eye showed mild conjunctivitis with a few conjunctival congestions and revealed two creamy, thread-like, mobile worms in the lower conjunctival sac. The patient reported that he had no contact with dogs or cats but remembered a fruit-fly-like insect that flew into his eye 1 month earlier. The worms were removed with ophthalmic forceps, and one worm was sent to our laboratory for morphology observation and the other worm was sent to a reference laboratory for molecular identification. Ocular symptoms resolved rapidly after the removal of the worms, with no recurrence upon 6-month follow-up.

Establishing in vitro and in vivo Co-culture Models of Staphylococcus epidermidis and Enterococcus faecalis to Evaluate the Effect of Topical Fluoroquinolone on Ocular Microbes.

Purpose: To establish in vitro and in vivo ocular co-culture models of Staphylococcus epidermidis and Enterococcus faecalis and to study how various concentrations of moxifloxacin affect the survival of these two endophthalmitis-causing bacteria.Methods: Standard strains of S. epidermidis and E. faecalis were used. Color detection agar plates were employed to distinguish their colonies. To establish the in vitro and in vivo co-culture models, S. epidermidis and E. faecalis were co-cultivated at different ratios for various periods. For the in vivo model, various volumes and concentrations of either a mono-culture or co-culture were inoculated into the lower conjunctival sac of rabbits. Finally, the newly developed in vitro and in vivo co-culture models were subjected to the moxifloxacin treatment to access its effect on S. epidermidis and E. faecalis.Results: When S. epidermidis and E. faecalis were cultured separately in tryptic soy broth, their growth peaked and plateaued at approximately 16 and 6 h, respectively. When they were co-cultured, the growth peak of S. epidermidis got delayed, whereas the growth peak of E. faecalis did not change. The number of E. faecalis was significantly higher in the co-culture than that in the mono-culture. Treatment with moxifloxacin in the in vitro co-culture model rapidly decreased the number of S. epidermidis cells at doses ≥ 0.125 μg/ml. In contrast, the number of E. faecalis did not change significantly up to 16 μg/ml moxifloxacin. In in vivo co-culture (at 1:1), the S. epidermidis count decreased in a pattern similar to that seen in in vivo mono-culture and was barely detectable at 24 h after inoculation. In contrast, the of E. faecalis count increased up to 16 h and then decreased. When moxifloxacin was applied (zero, one, or two times) to this model, the S. epidermidis count decreased in proportion to the number of treatments. In contrast, the E. faecalis count increased with moxifloxacin treatment.Conclusions: The in vitro and in vivo co-culture models of S. epidermidis and E. faecalis were established to determine the influence of moxifloxacin eye drops on these bacteria. The results clearly show that the moxifloxacin eye drops can make E. faecalis dominant on the ocular surface.

Short-term effect of non-preserved cationic oil-in-water ophthalmic emulsion on tear meniscus parameters of healthy individuals in a prospective, controlled pilot study.

This study investigated the effect of instilling a single drop of non-preserved cationic oil-in- water ophthalmic emulsion (Cationorm®) on the lower (LTM) and upper tear meniscus (UTM) parameters of normal eyes. In this prospective, single-center, non-randomized, controlled pilot study, optical coherence tomography was used to estimate the UTM and LTM height, depth, and cross-sectional area in participants without a history of dry eye disease. In the right eye (study eye), we instilled one drop of Cationorm® in the lower conjunctival sac. Scans of the tear menisci were acquired at baseline, before the instillation, and at 5, 15, and 30 min thereafter. Control scans of the left eye (control eye) were obtained at the same timepoints. The tear meniscus parameters of the study eye were compared with the control eye at each timepoint. Twenty subjects (11 male and 9 female; mean [standard deviation] of age: 37.8 [10.9] years) were included in the study. Compared to the control eye, instillation of a single drop of Cationorm® resulted in significantly higher LTM parameter values and a higher UTM cross-sectional area up to 30 min after instillation (all P < 0.05). The UTM height and depth were significantly greater in the study eye than in the control eye up to 5 min (P < 0.001 and 0.007, respectively) and 15-min (P = 0.045, and 0.002, respectively) after Cationorm® instillation. In the study eye, Cationorm® resulted in a significant increase in LTM parameter values up to 30 min post-instillation (all P < 0.001). The UTM height was significantly greater up to 15 min post-instillation than at baseline. The UTM depth and area increased significantly from baseline to 5 min after instillation (P = 0.043, and 0.002, respectively). Cationorm® seems to have a prolonged residence time on the ocular surface of healthy subjects as indicated by LTM parameters and to a lesser extent by UTM parameters.

تعیین مقدار قابل ارجاع برای اندازهگیری میزان اشک چشم با استفاده از نوار آزمایش اشکی (STT) در اسبچه خزر

BACKGROUND: The Schirmer tear test (STT) is widely used in both human and veterinary ophthalmology. Two types of STTs have been developed: STT I and STT II. OBJECTIVES: The purpose of this research was to determine the reference value for measuring tear production of the Caspian horse by using the Schirmer tear test strip. METHODS: Twenty apparently healthy male and female Caspian horses, aged between 2 and 15 years old and weighing between 192±32 Kg were selected. After physical examination and reviewing the horse's health history and assuring their health, the Schirmer tear test was performed. To produce a higher volume of tears in horses, compared to other animal species, we used the Schirmer tear strip (Schirmer‐ Eickemeyer®, Germany), for 30 seconds instead of one minute in the lower conjunctival sac. In this study, we investigated the effect of age and gender on tear production in the Caspian horse, as well as the comparison between the left and right eyes tear production. RESULTS: The study shows that the results of STT I in the study animals illustrated the mean±SD STT I value was 23.38±3.6 mm/min (range, 15–30 mm/30s). Based on the results of this study, the variants of age and gender had no significant effects on the STT1 results in the Caspian horses. No significant difference was noted between the amount of tear production in the left and right eyes. CONCLUSIONS: Considering the importance of rapid diagnosis of dry eye syndrome and preventing its subsequent disorders such as Keratoconjunctivitis Sicca, the results of this study can be used as the reference value in the future to measure the amount of moisture of caspian horses of the Caspian horse.

The Microbiome of the Meibum and Ocular Surface in Healthy Subjects.

PurposeThe purpose of this study was to investigate the microbiome in the meibum, conjunctival sac, and eyelid skin in young and elderly healthy subjects, and analyze the effect that age, sex, and region have on microbiome composition.MethodsThis study involved 36 healthy subjects (young-age subjects: 9 men/9 women, age range: 20–35 years; elderly age subjects: 9 men/9 women, age range: 60–70 years). In all subjects, lower-eyelid meibum, lower conjunctival sac, and lower-eyelid skin specimens were collected from one eye, and then stored at –20°C. Taxonomic composition of the microbiome was obtained via 16S rRNA gene sequencing, and then analyzed.ResultsThe meibum microbiome showed a high α-diversity (within-community diversity), particularly in the young subjects. However, in approximately 30% of the elderly subjects, a low-diversity microbiome dominated by Corynebacterium sp. or Neisseriaceae was observed. In the young subjects, the microbiome of the meibum resembled that of the conjunctival-sac, yet in the elderly subjects, the microbiome of the conjunctival-sac became more similar to that of the eyelid skin. The eyelid-skin microbiome was relatively simple, and was typically dominated by Propionibacterium acnes in the young subjects, or by Corynebacterium sp. or Neisseriaceae in the elderly subjects. In both age groups, no significant difference was seen between the men and women in regard to the meibum, conjunctival-sac, and eyelid-skin microbiome.ConclusionsOur findings confirmed that the meibum of healthy adult-age subjects harbors highly diverse microbiota, and revealed that the meibum microbiome, especially the decrease of its diversity, alters with aging and may affect the homeostasis of the ocular surface.

Conjunctival flora in anophthalmic patients: microbiological spectrum and antibiotic sensitivity.

To identify the spectrum and susceptibility pattern of isolated microorganisms from conjunctival flora of anophthalmic patients. A cross-sectional clinical study including 60 patients with unilateral anophthalmia. Patients with use of antibiotic drops in their socket during the last month were also included. From each patient, three microbiological samples were taken from the lower conjunctival sac (healthy eye, pre-prosthesis, and retro-prosthesis space of socket). The 180 samples obtained were cultured. Isolates were identified and their antibiotic sensitivities were determined. A total of 251 isolates were recovered (62 isolates from healthy eye, 93 from pre-prosthesis, and 96 from retro-prosthesis space). The most common organism was Staphylococcus epidermidis, in both healthy eyes (64.5%) and sockets (45.5%). Altogether, coagulase-positive Staphylococci, Streptococci, and Gram-negative bacteria accounted for less than 15% of isolates in healthy eyes and more than 35% in sockets. Regarding the antibiotic sensitivities, there were no significant differences between isolates from sockets and healthy eyes. Nine patients recognized the use of self-prescribed antibiotic drops in their socket. In the healthy eyes of these subjects, Gram-positive microorganisms showed significantly greater resistance to aminoglycosides and tetracycline. Sockets of anophthalmic patients show a greater number of pathogens compared to healthy eyes. The use of antibiotic drops in the socket promotes a resistant flora not only in the socket but also in the healthy eye. Quinolones and macrolides may be better therapeutic options than aminoglycosides for treating conjunctivitis of anophthalmic sockets, since these antibiotics are less active against Staphylococcus epidermidis.

Visualization of Tear Clearance Using Anterior Segment Optical Coherence Tomography and Polymethylmethacrylate Particles.

We previously reported 2 new methods, anterior segment optical coherence tomography (AS-OCT) and polymethylmethacrylate particles suspended in fluorescein solution (PPF), for the evaluation of tear clearance and rapid tear flow after blinking (tear Krehbiel flow). Here, we investigated age-related OCT tear clearance and tear film thickness (TFT) and the potential correlation of OCT tear clearance and PPF velocity indicative of tear Krehbiel flow. Normal subjects separated into young and older groups received 5 μL of saline solution into the lower conjunctival sac, and an image of the central lower eyelid tear meniscus was captured by AS-OCT immediately and 30 seconds after natural blinking. Tear meniscus height (TMH) and tear meniscus area (TMA) were measured, and their percentage decrease was defined as OCT clearance rate. A Spectralis OCT Anterior Segment Module captured the central corneal tear film layer for TFT measurements. OCT clearance rates were significantly higher in young versus older subjects (P = 0.0002). When all subjects were analyzed, age was significantly and negatively correlated with TMH clearance rate (r = -0.4928, P = 0.0003) and TMA clearance rate (r = -0.4596, P = 0.0008). TFT values were significantly and negatively correlated with age (r = -0.6662, P < 0.0001). A second experiment examined tear Krehbiel flow by measuring PPF velocity in frontal and medial gaze positions. The medial gaze position showed significantly increased PPF velocity compared with the frontal gaze position (P = 0.006). Significant and positive correlations were found between OCT clearance rates and PPF velocity (TMH rate: r = 0.2926, P = 0.0392; TMA rate: r = 0.3274, P = 0.0205). AS-OCT and PPF might be novel techniques for quantitative evaluation of tear clearance and Krehbiel flow.

Etiological characteristics of chlamydia trachoma conjunctivitis of Primary Boarding School students in the Qinghai Tibetan area.

The aim of this study was to investigate the etiological characteristics of Chlamydia trachomatis conjunctivitis among resident students at primary schools in the Qinghai Tibetan area in order to understand the distribution of C. trachomatis and other pathogenic microorganisms, to detect the isolation rate of infectious pathogens, and to provide an evidence for further targeted efforts in the prevent of sporadic trachoma efforts. From two primary schools in Qinghai Province, ocular samples from 35 students who were clinically diagnosed as trachoma cases and 60 normal controls were obtained by swabbing their upper eyelids and lower conjunctival sacs. Samples were preserved at 4°C and airlifted to Beijing Tongren Hospital within 24 h. Real- time polymerase chain reaction (RT-PCR) was used to screen for C. trachomatis, and nested PCR was used to amplify a fragment of the ompA gene for serotype confirmation. Bacterial cultivation and sensitivity tests were conducted based on the 2015 version of the Clinical and Laboratory Standards Institute. Adenovirus, herpes simplex virus, cytomegalovirus, and Epstein-Barr virus were screened by RT-PCR. Among the 35 students with trachoma, 8 came from the Jianshetang Primary School and 27 came from the Central Primary School. Two novel C. trachomatis B serotypes (GenBank accession numbers KU737520 and KU737521) were detected based on a sequence analysis of the ompA gene. Single C. trachomatis infections accounted for 42.86% (9/21) of the cases, and infections with multiple bacteria, particularly Haemophilus influenzae, Staphylococcus aureus, Moraxella catarrhalis, and Streptococcus pneumoniae, accounted for the remaining 57.14% (12/21). Of the 14 C. trachomatis-negative samples, one was positive for adenoviral infection (serotype D) and 13 were positive for bacterial infections (H. influenzae, M. catarrhalis, S. pneumoniae, S. aureus, streptococci other than S. pneumoniae, Staphylococcus epidermidis, Corynebacterium, and Arthrobacterium). In addition to C. trachomatis, the other bacteria and virus that were detected in the boarding students of primary schools in the Qinghai Tibetan area should be emphasized in trachoma prevention and control.

A histamine-independent itch pathway is required for allergic ocular itch

Non-histaminergic TRPA1 neural pathway is required for the development of allergic ocular itch. Pharmacological inhibition of TRPA1 channel can lead to novel therapeutic strategies to treat ocular itch in severe allergic conjunctivitis.

Absorption and distribution characteristics of terbinafine hydrochloride nanoemulsions in cornea after instillation

Background Nanoemulsions (NEs) is one of the most popular ophthalmic colloidal drug delivery system due to its long-term stability, low toxicity and irritancy, considerable capacity for solubilization of lipophilic drug molecules and great potential in bioavailability improvement.The cornea pathway is the main route of intraocular absorption after topical use of NEs.Though NEs possess numerous physiological and physicochemical advantages, the use of NEs cannot always obtain satisfactory results. Objective This study was to investigate the impacts of epithelium and stroma on the corneal permeation of topical ophthalmic terbinafine hydrochloride nanoemulsions (TH-NEs). Methods TH-NEs was prepared by the self-emulsification method.The size and Zeta potential of the oil droplets in the formulation were analyzed using a dynamic light-scattering particle size analyzer.The high performance liquid chromatography (HPLC) was used for the in vitro release study.Sixty New Zealand albino rabbits were randomly divided into intact cornea group and cornea epithelium debrided group.The cornea epithelium of the left eyes was debrided in the cornea epithelium debrided group.The TH-NEs were instilled into the lower conjunctival sac of left eyes.Six rabbits were executed from each group 15, 30, 60, 120 and 240 minutes after dosing, respectively.The corneas were collected and analyzed by HPLC.The fluorescein diacetate (FDA) was used to label the TH-NEs.Two C57BL/6 mice with left cornea epithelium debrided and 2 normal mice were used for the fluorescence tracing study.The fluorescence distribution of FDA labeled TH-NEs was observed by a two-photon laser confocal scanning microscope 30 minutes and 60 minutes after single instillation. Results The average size and Zeta potential of the oil droplets were 51.37 nm and -0.232 7 mV respectively, and 0.482% of encapsulated drugs was released from the TH-NEs after 12 hours.The peak concentrations of TH in the intact cornea and epithelium debrided cornea were (17.85±2.79)μg/g and (4.40±1.75)μg/g respectively, which occurred 15 minutes post-dose.The drug concentrations in the intact cornea were significantly higher than that in the debrided cornea 15, 30, 60 and 120 minutes after dosing, with significant differences between them (t=9.998, 8.658, 6.903, 7.576; all at P=0.000). The fluorescence was observed in the cornea epithelium when the cornea was intact.The fluorescence intensity in the superior layer of corneal epithelium was obviously higher than that in the deep layers of corneal epithelium 30 minutes and 60 minutes after dosing.No fluorescence was observed in the cornea stroma of both eyes. Conclusions The cornea epithelium is the main of absorption and distribution position of TH-NEs.The cornea stroma is the dominating permeation barrier for the intraocular transportation of the TH-NEs.The cornea stroma may stop the permeation of TH-NEs by molecular exclusion mechanism. Key words: Terbinafine hydrochloride; Nanoemulsions; Corneal epithelium; Corneal stroma; Tissue distribution

The Role of Staphylococcal Enterotoxin in Atopic Keratoconjunctivitis and Corneal Ulceration

H Fujishima, N Okada, M Dogru. Allergy. 2012;67(6):799–803 To determine whether staphylococcal enterotoxin (SE) has a role in the pathogenesis of atopic keratoconjunctivitis (AKC) and corneal ulceration Forty-five subjects were enrolled (18 with AKC, mean age 16.9 years; 9 with vernal keratoconjunctivitis [VKC], mean age 12.9 years; 10 with seasonal allergic conjunctivitis [SAC], mean age 21.9 years, and 8 healthy volunteers, mean age 21.6 years). Upper tarsal conjunctiva, lower conjunctival sac, and upper lid margin skin were swabbed for …

New method for evaluation of early phase tear clearance by anterior segment optical coherence tomography

To describe a new method of measuring early phase tear clearance by anterior segment optical coherence tomography (AS-OCT). Sixty normal subjects were divided into a young group (30 subjects; 29.6 ± 7.2 years) and an elder group (30 subjects; 71.4 ± 10.8 years). AS-OCT (CASIA SS-1000, Tomey, Japan) with customized software was used to record the tear meniscus at the centre of the lower eyelid. Five microlitres of lukewarm saline solution was dropped into the lower conjunctival sac, and an image of the tear meniscus was obtained immediately and again 30 seconds after natural blinking. The tear meniscus height (TMH) and tear meniscus area (TMA) were measured in the AS-OCT images, and the percentage decrease in the TMH and TMA was used as a measure of the tear clearance. Correlations between tear clearance and clinical features including degree of conjunctivochalasis, degree of protrusion of inferior lacrimal punctum, distance of lacrimal punctum from the Marx line and fluorescein clearance rates were also determined in another healthy population consisting of 30 subjects. The OCT tear clearance rate was 35.2 ± 11% for TMH and 28.1 ± 12.4% for TMA in the young group, and 12.4 ± 7.3% and 6.2 ± 9.1%, respectively in the elder group. The differences were significant for both the TMH (p = 0.017) and the TMA (p = 0.024). The OCT-determined tear clearance was positively correlated with the fluorescein clearance rate, and negatively correlated with the distance between the lacrimal punctum and Marx line, degree of conjunctivochalasis and degree of lacrimal punctum protrusion. AS-OCT can be used as a rapid, non-invasive and quantitative method of determining the early phase tear clearance rate in a normal healthy population.

Ulcera escleral secundaria a quemadura química por pila de reloj y cuerpo extraño retenido en fondo de saco conjuntival inferior: Caso clínico

abstract scleral ulcer secondary to chemical burn caused by watch battery and retained foreign body in conjunctival sac inside. case report introduction: Approximately one-third of childhood blindness is due to trauma, representing the leading cause of visual impairment and monocular blindness in children. case report: the patient is a 2 year old pre-school boy, who presented scleral ulcer in his left eye secondary to chemical burn caused by watch battery. the reason for seeking medical care was difficult healing caused by a mineral foreign body retained in the lower conjunctival sac after the patient came in contact with detergent one month before the pediatric consultation. Discussion: An unusual case of scleral ulcer was reported. So far, no other similar cases have been reported. the diagnosis process and the delay for the removal of the foreign body are emphasized in this serious ophthal-mologic emergency. (Key words: Chemical burn, scleral ulcer, ocular trauma).Rev Chil Pediatr 2012; 83 (6): 582-586

Clinical Treatment of Dry Eye Using 0.03% Tacrolimus Eye Drops

To report the clinical outcome of the treatment of dry eyes using 0.03% tacrolimus eye drops (olive oil + tacrolimus 0.03%) (Ophthalmos, Sao Paulo, Brazil). Sixteen eyes of 8 patients with Sjögren syndrome dry eyes (age, 51.13 ± 9.45 years) were enrolled in this study (prospective noncontrolled interventional case series). Patients were instructed to use topical 0.03% tacrolimus eye drops twice a day (every 12 hours) in the lower conjunctival sac. Schirmer I test, break-up time, corneal fluorescein, and rose bengal staining score were performed in all patients 1 day before, and 14, 28, and 90 days after treatment with 0.03% tacrolimus eye drops. The average fluorescein staining and rose bengal staining scores improved statistically significantly after 14 days of treatment and improved even more after 28 and 90 days. The average Schirmer I test did not improve statistically significantly after 28 days of treatment, although we did observe a significant improvement after 90 days of treatment with 0.03% tacrolimus eye drops. The average break-up time did not improve statistically after 14 days of treatment, although we observed a significant improvement after 28 and 90 days of treatment with 0.03% tacrolimus eye drops. Topical 0.03% tacrolimus eye drops successfully improved tear stability and ocular surface status in patients with dry eyes.

The role of Staphylococcal enterotoxin in atopic keratoconjunctivitis and corneal ulceration

Patients with atopic eczema frequently experience colonization with Staphylococcus aureus that is directly correlated with the eczema severity. We hypothesized that S. aureus-secreted enterotoxins (SE) are involved in the pathophysiology of atopic keratoconjunctivitis (AKC). A total of 45 subjects (18 with AKC, nine vernal keratoconjunctivitis (VKC), eight seasonal allergic conjunctivitis (SAC), and ten healthy volunteers) were enrolled. Slit lamp examinations, including fluorescein staining, were performed. Scraped samples were collected from the upper tarsal conjunctiva, lower conjunctival sacs, and the skin around the eyelid margins. Superantigen (SAg) genes were detected using polymerase chain reaction (PCR). Among 45 cases, S. aureus was detected significantly more in AKC patients than VKC patients (P = 0.026), SAC patients (P = 0.0003), and healthy volunteers (P = 0.0001). SAg genes were detected in 11 patients. SEB (2/11), SEG (8/11), and SEI (8/11) were detected, but no other SE. There was a significant difference in SE detection between AKC and SAC patients (P = 0.03). In severe types of ocular allergic disease such as AKC and VKC (N = 27), SE was detected in six of ten patients with corneal ulcers and two of 17 patients without corneal ulcers. SE was detected in significantly more patients with corneal ulcers (P = 0.025). In patients with AKC, S. aureus and SE were detected more frequently compared with other patients and healthy volunteers, especially in association with corneal ulceration suggesting a role of SE. So far, it is unknown whether SE leads to tissue damage of the cornea by initiating an immune response or has direct toxic effects.

Effects of the folk medicinal plant extract Ankaferd Blood Stopper® on the ocular surface

Purpose: To investigate the effects of Ankaferd Blood Stopper® (ABS) on the ocular surface.Methods: Twenty adult male Wistar albino rats, weighing 390–530 g, were used in this prospective, controlled trial. One drop of ABS and one drop of balanced salt solution (BSS) were instilled into the lower conjunctival sac of the right and left eyes, respectively. After the rats were anesthetized, the ocular surface was evaluated based on the Draize criteria, and fluorescein tests were performed at 1, 2, 4, 18, 24, and 48 h. Subsequently, the rats were killed and all eyes were enucleated for histopathological examination.Results: The outcome of the Draize and fluorescein tests revealed that ABS caused more irritation of the ocular surface than BSS (P < 0.001). The highest mean ABS score was 4.9 for the Draize test and 0.4 for the fluorescein test, and ABS was considered to be a slight irritant. Histopathological examinations of the cornea and the conjunctiva revealed no significant difference between the eyes instilled with BSS and those instilled with ABS.Conclusions: ABS is a hemostatic drug that exerts a slight toxic effect on the ocular surface. Given its ease of use and antibacterial activity, as well as its efficiency in stopping bleeding, the use of ABS during ocular surgery should be further investigated in experimental and clinical studies.

Microbiota bacteriana da conjuntiva no pré-operatório de injeção intravítrea de antiangiogênico por degeneração macular relacionada à idade comparada com a de cirurgia de catarata

To evaluate the conjunctival bacterial microbiota and antibiogram profile in the preoperative of antiangiogenic intravitreous injection for age-related macular degeneration, and compare to the preoperative microbiota of patients submitted to cataract surgery.Cross-sectional, observational, case series study. Two groups were organized: group I (macular degeneration) with 26 eyes from 26 patients (12 men/14 women) with mean age of 69.2 +/- 11.5 years; group II (cataract) with 27 eyes from 27 patients (9 men/18 women) with mean age of 67.6 +/- 7.9 years. The groups were similar regarding age (p=0.538) and gender (p=0.787). The lower conjunctival sac was swabbed and the obtained material was immediately put in a tube filled with liquid culture media BHI ("brain heart infusion"). Samples were processed according to standard laboratory techniques and antibiogram was determined for each bacterial colony.Twenty-six bacterial colonies growth in group I, with 2 eyes showing no growth and 30 colonies growth in group II. Gram positive bacteria were more prevalent in both groups: 23/26 colonies (88.4%) in group I and 29/30 colonies (96.7%) in group II, with a Staphylococcus aureus predominance in both groups, with 16 samples (61.5%) and 17 (56.7%), respectively. Coagulase negative Staphylococcus was the second most common identified bacteria, with 19.2% in group I and 20.0% in group II. No differences between the groups reached statistical significance. No statistically significant difference was noted on the antibiotic sensibility between both groups.There was no difference in the distribution of bacteria and antibiogram profile of the conjunctival microbiota in the preoperative of intravitreous injection of antiangiogenic for macular degeneration compared to the preoperative of cataract surgery.

High-Resolution Genome Profiling DifferentiatedStaphylococcus epidermidisIsolated from Patients with Ocular Infections and Normal Individuals

To investigate the potential phenotypic and genetic differences among the Staphylococcus epidermidis isolates obtained from control subjects (lower conjunctival sac; n = 14) with those from patients with keratitis (corneal scrapings; n = 18) or endophthalmitis (vitreous; n = 24). Biofilm-forming capacity was detected by PCR for the icaAB gene and phenotyping by microtiter plate assay and congo red agar plate. Genotyping was performed by using fluorescence-amplified fragment length polymorphism (FAFLP) and in silico analysis of the FAFLP profiles. Biofilm phenotyping (congo red agar/microtiter plate) differentiated disease-causing strains from control subjects. PCR assays (mecA, icaAB) were not useful in differentiating disease-causing strains from that of control subjects. The biofilm-forming capability appeared more critical in the pathogenesis of keratitis than in that of endophthalmitis. Cluster analysis of FAFLP data generated 11 clusters comprising 4 major clusters (I, II, III, and V) and 7 minor ones. FAFLP analysis clearly showed clustering of most of the commensal isolates in cluster I, separate from keratitis and endophthalmitis isolates. In silico analysis mapped signature bands to genes such as ebh, tagD, ptsI, and sepA, which might have a significant role in transforming less virulent populations of S. epidermidis to more virulent ones. The population dynamics of S. epidermidis revealed that there are significant genetic variations that can be detected through FAFLP between ocular disease causing isolates and the commensal population.

A Mathematical Model of Tear Mixing under the Lower Lid

Purpose: The degree of tear mixing in various parts of eyes plays an important role in determining some important aspects of tear dynamics. This study develops a mathematical model of tear mixing in the lower conjunctival sac. Method: Tear mixing in the lower conjunctival sac is modeled using Taylor dispersion. The concentration of instilled solutes is obtained numerically from an equation set that integrates the mass balance of solutes in the lower conjunctival sac and the exposed tear film. Results: The time for dye to appear in the exposed tear film and the time for maximal dye concentration after instillation into the lower conjunctival sac vary for different amplitudes and frequencies of lid motion. The time scales for mixing are in qualitative agreement with experiments reported in the literature. Conclusion: This study supports the hypothesis that the tear mixing in the lower conjunctival sac is driven by Taylor dispersion caused by lid/globe movements during blinking.

Effects of travoprost 0.004% ophthalmic solution, six weeks after its laminated packaging had been removed, in primary open-angle glaucoma: A randomized, controlled, investigator-blinded study

Background: Primary open-angle glaucoma (POAG) is a chronic and progressive optic nerve and retinal nerve fiber layer neuropathy, with characteristic visual field damage. The intraocular pressure (IOP) is typically higher than the level considered statistically normal. Although there is no known cure, appropriate reduction of IOP with hypotensive drugs (eg, the topical prostaglandin analogue travoprost) delays the progression of POAG. Chemical-stability studies of travoprost performed by the manufacturer suggest that the stability of travoprost is maintained beyond the expiration date, which is 6 weeks after the laminated packaging has been opened. Objective: The goal of this study was to assess the efficacy and tolerability of travoprost 0.004% ophthalmic solution, 6 to 12 weeks after its expiration date, in patients with POAG. Methods: This randomized, controlled, investigator-blinded study was conducted at 2 centers in Brazil: the Ophthalmology Department, Federal University of Goi s, Goi nia, and the Ophthalmology Department, Santa Casa de Misericordia Hospital in S o Jos do Rio Preto, Sao Paulo. Patients with POAG (in 1 or both eyes) were randomly assigned to receive travoprost, either from a bottle from which the laminated packaging had been removed and that had been stored at room light and temperature for 6 weeks (ie, after the expiration date; opened group), or from a bottle that had been sealed until first use by the patient (control group). Drug was to be administered, 1 drop in the lower conjunctival sac (in the affected eye[s]), QD between 7 pm and 9 pm, for 6 weeks. IOP was measured at study weeks 0 (baseline), 4, and 6. The 2 treatment groups were compared with regard to hypotensor effect and incidence of adverse events (AEs). Results: Thirty-one patients completed the study (55 eyes; 28 right and 27 left eyes; 35 eyes of women, 20 eyes of men). The mean (SD) ages of the opened and control groups were 61.8 (13.5) and 62.8 (14.1) years, respectively. Twenty-four patients were included in both treatment groups (ie, 1 eye per group). The baseline IOP was similar between the 2 treatment groups. There was a significant reduction in IOP in both groups at 4 and 6 weeks (both, P < 0.001 vs baseline). However, no significant differences in IOP were found between the 2 treatment groups at any time during the study. Conjunctive hyperemia and a burning sensation in the eye immediately after application were the only AEs reported; the incidence of these was similar between the 2 treatment groups. Conclusions: In this study of patients with POAG, IOPs and AEs were similar in eyes receiving 6 weeks of treatment with travoprost 0.004% ophthalmic solution, either from bottles from which the laminated packaging had been opened and that had been stored at room light and temperature for 6 weeks (ie, after the expiration date), or from bottles that had been sealed until first use by the patient. These results suggest that travoprost remains effective for at least 12 weeks after the laminated packaging has been opened.