Eye Fluid Research Articles

Transcription Factor CHF1/Hey2 Regulates Specific Pathways in Serum Stimulated Primary Cardiac Myocytes: Implications for Cardiac Hypertrophy

We have previously found that overexpression of CHF1/Hey2 in the myocardium prevents the development of phenylephrine-induced hypertrophy. To identify transcriptional pathways regulated by CHF1/Hey2, we cultured primary neonatal mouse cardiac myocytes from wild type and transgenic mice overexpressing CHF1/Hey2 and treated them with serum, a potent hypertrophic stimulus. We verified that overexpression of CHF1/Hey2 suppressed cardiac myocyte hypertrophy induced by serum and then determined transcriptional profiles by microarray hybridization. We identified and verified important downstream target genes by single gene analysis and qRT-PCR and then identified important biological processes by Gene Set Analysis using Biological Process Gene Sets from the Gene Ontology Consortium. We found that CHF1/Hey2 suppresses pathways involved in water transport, adenylate cyclase activity, embryonic eye morphogenesis, gut development and fluid transport after serum stimulation. Genes involved in protein dephosphorylation, demonstrate increased expression in myocytes overexpressing CHF1/Hey2, independent of serum treatment. Genes overexpressed prior to serum treatment are involved in regulation of transcription factor activity, nuclear protein export and steroid hormone receptor signaling. Genes overexpressed after serum treatment are involved in autophagy, apoptosis and mitochondrial biogenesis.

Comparative Study of the Degree of Severity of Hepatitis B in Preicteric, Icteric and Posticteric Hbsag Seropositive Patients Using ALT, AST, Cu, Fe, Mn, Se, Mg, Zn and Albumin

Jaundice is the yellowish pigmentation of sclera of eye, skin and body fluids. It is associated with hepatitis Bvirus infection due to the destruction of the infected hepatocytes and intrahepatic-cholestasis caused by the scarsof the healed hepatocytes. Hepatitis B patients that have never had jaundice are referred to as preicteric patients,while those that have recovered from jaundice are referred to as posticteric hepatitis patients. Those onessuffering from jaundice are referred to as icteric patients. This research work was designed to determine andcompare the severity of hepatitis B using the serum levels of liver enzyme, albumin and micronutrients inHBsAg seropositive patients. One hundred and fifty HBsAg seropositive critically ill rural patients of theAtisbo/Saki-East/Saki-West federal constituency aged 5- 79 years; (75 females: 75males) classified intopre-icteric, icteric and posticteric patients were successfully monitored and investigated. One hundred and twelveHBsAg seronegative and HBV non-infected apparently healthy volunteers from the same community aged 4-80years were studied as normal control volunteers. Forty three HBsAg seropositive patients were recruited fromIbadan as urban reference. The presence of hepatitis B surface antigen (HBsAg) and envelope antibodies tohepatitis B, (anti-HBe) were determined in the test and control subjects serologically (ELIZA). Similarly, theserum levels of liver enzymes Alanine-aminotransferase (ALT), and Aspartate-aminotransferase (AST) andmicronutrients (Cu, Zn, Fe, Mn, Mg and Se) were biochemically (spectrophotometry and atomic absorptionspectrophotometry) determined. Liver enzymes and albumin assays were routinely employed to recruit HBsAgseropositive patients in active liver destruction. Antibody to envelope antigen was used to detect patients that areinfected but have been cleared of the antigens(HBsAg and HBeAg). The results obtained showed a significantlyhigher mean serum values of AST,ALT,Fe,Cu and Mn with a significantly lower serum albumin, Se,Mg,and Znlevels in patients compared with the results obtained from the controls during the 1st bleeding with P

Pan-resistant Acinetobacter Infection in Neonates in Karachi, Pakistan.

Pan-resistant Acinetobacter infection has emerged as an important nosocomial pathogen in our inpatient neonates over the past few years. We performed a retrospective chart review during a five-year period (July 2003 - June 2008) of all neonates hospitalized in our neonatal intensive care unit (NICU) who developed Acinetobacter infection to identify mortality-associated risk factors in Acinetobacter neonatal infection. During the five-year study period, 122 cultures from 78 neonates grew Acinetobacter. Source sites of positive culture were in the following descending order: blood (n = 57), trachea (n = 55), tissue/wound/body fluids (n = 4), eye (n = 4), urine (n = 1), and cerebrospinal fluid (n = 1). Twenty-four (31%) patients had Acinetobacter isolated from more than one site. At the time of admission the mean age was 2.08 +/- 4 days and mean weight was 1.77 +/- 0.88 kg; 75% were premature. Pan-resistance (87/122; sensitive only to Polymyxin) was present in 71% of Acinetobacter isolates. Crude mortality rate of this cohort was 47%, while 70% of patients died within four days after positive Acinetobacter culture. We identified weight of less than 1 kg on admission (p 0.06, adjusted Odds Ratio (AOR) 1.53), gestational age 28 weeks or less (p 0.011, AOR 2.88), poor perfusion (p 0.007, AOR 2.4), thrombocytopenia (p 0.01; AOR 1.6) and metabolic acidosis (p 0.01; AOR 1.67) as predictors associated with poor outcome. Pan-resistant Acinetobacter infection is exceedingly fatal in newborns, particularly in premature and very low-birth weight neonates. Rational antibiotic use and vigilant infection control in NICUs are key to controlling multi-drug resistant Acinetobacter infection and improving clinical outcome.

Prognostic Significance of Delayed Structural Recovery after Macular Hole Surgery

To assess the prognostic significance for visual function of persistent subfoveal fluid and persistent photoreceptor layer discontinuity in eyes in which hole closure had been obtained 3 months after macular hole surgery. Ancillary study of subjects enrolled in a randomized clinical trial. Participants were recruited from a randomized clinical trial evaluating internal limiting membrane (ILM) peeling in macular hole surgery. The study included 74 eyes in which a contiguous retinal surface or a full attachment with a flat neuroretinal rim had been reestablished after macular hole surgery. Contrast-enhanced optical coherence tomography was used to detect closure defects involving substrata of the retina with particular emphasis on the photoreceptor layer. Outcomes were compared with best-corrected visual acuity (BCVA) 12 months after surgery. Postoperative foveal configuration and foveal photoreceptor layer discontinuity diameter 3 months after macular hole surgery. Persistent subfoveal fluid 3 months after macular hole surgery, which was found in 36.5% of eyes, was not associated with a significantly different BCVA after 12 months compared with eyes with a fully attached fovea at 3 months (70.9 letters vs. 72.0 letters; P = 0.59). Receiver operating characteristics curve analysis identified persistent photoreceptor layer discontinuity of a diameter of more than 1477 microm after 3 months to be associated with poorer BCVA after 12 months (P<0.001), yet an overall reduction in discontinuity diameter from 3 to 12 months (P<0.001) was not correlated with a concurrent improvement in BCVA (r = -0.040; P = 0.81). Persistence of fluid and diameter of discontinuity at 3 months were not related to whether ILM peeling was used; however, secondary macular hole surgery had a significant influence on diameter of photoreceptor layer discontinuity at 3 months. Structural recovery in the form of photoreceptor layer discontinuity with a diameter of more than approximately 1500 microm 3 months after macular hole surgery was associated with poorer visual acuity after 12 months than less extensive discontinuity. Subfoveal fluid persisting after 3 months had disappeared after 12 months in all but 5 of 74 eyes and had no effect on final visual outcome.

Macular edema and neovascularization in a case of Stargardt macular dystrophy

Abstract Purpose To present a case of macular edema and neovascularization in a patient who was diagnosed with Stargardt macular dystrophy. Methods We present the case of a 22 year old male who experienced visual deterioration in his left eye. At presentation his visual acuity was OD 8‐9/10 and OS 6‐7/10. OCT scan, fluoroangiography (FA) and electroretinografy (ERG), were performed. Results OCT scan revealed cystoid macular edema in the right eye, and increased reflectivity of the pigment epithelium and some subretinal fluid in the left eye. FA findings were consistent with Stargardt dystrophy. However in the right eye an area of increasing hyperfluorescence was observed (presence of neovascularisation). ERG: subnormal photopic and scotopic responses. The color vision was impaired mainly in the left eye. Following the experience of other investigators acetazolamide was administered orally (300 mg per day) and resolution of the cystoid edema was obvious in OCT scan after 20 days. The visual acuity increased (OD 10/10 and OS 8/10). Two weeks after the discontinuation of acetolozamide the macular edema reappeared and the visual acuity diminished: OD 8‐9/10 and OS 6‐7/10. Conclusion This is a peculiar case of cystoid macular edema and neovascularization in Stargardt macular dystrophy. Our findings suggest, in consistency with other investigators, that administration of oral acetozolamide may be beneficial for the resolution of macular edema. The neovascularization in the left eye remained stable during the follow up period and it was considered that any intervention was not necessary at that time.

Should Rheumatologists Retain Ownership of Fibromyalgia?

<h3>Background/aims</h3> To understand changes in disease activity as assessed by leakage and retinal fluid status in patients with neovascular age-related macular degeneration (nAMD) receiving fixed dosing with an anti-vascular endothelial growth factor (anti-VEGF) agent. <h3>Methods</h3> In the phase III VIEW 1 (NCT00509795) and VIEW 2 (NCT00637377) studies, eyes with nAMD were treated with intravitreal aflibercept or ranibizumab. Independent, masked reading centres determined the presence/absence of leakage (fluorescein angiography) and retinal fluid (optical coherence tomography) at baseline, week 24 and week 52. In this integrated, post hoc analysis of the VIEW studies, the relationship between leakage/fluid status and best-corrected visual acuity (BCVA) was assessed. The impact of baseline lesion type (predominantly classic (PC), minimally classic (MC), occult) was also evaluated. Data from all treatment groups were pooled. <h3>Results</h3> 2373 eyes were included in this analysis. At baseline, 95.4% of eyes presented with both leakage and fluid. By week 52, leakage and fluid were present in 16.0% of eyes. Mean BCVA gains at week 52 were numerically greater in eyes without leakage and fluid versus eyes with both leakage and fluid (10.3 vs 9.2 letters). At week 52, 11.6%, 15.3% and 20.1% of eyes with PC, MC and occult lesions, respectively, had both leakage and fluid present. <h3>Conclusion</h3> In this post hoc analysis, fixed dosing with an anti-VEGF agent over 52 weeks eliminated disease activity (absence of both leakage and fluid) in most eyes. The effect of anti-VEGF treatment on leakage/fluid status favoured PC versus occult lesions.

The expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy

To explore the expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy, and to analyze the relative factors. It was a case-control study. Data of 50 eyes of 50 PDR patients who underwent vitrectomy were retrospectively analyzed. The vitreous fluid samples were obtained during surgery. The VEGF level in vitreous fluid was determined by enzyme linked immunosorbent assay, and the expression of vascular endothelial growth factor of vitreous in patients with proliferative diabetic retinopathy was analyzed. The mean follow-up was 9 months with a range from 6 to 26 months. The VEGF levels in vitreous fluid were compared between PDR patients and normal control, and silicone oil tamponade group and without silicone oil tamponade group by t-test. The changes of VEGF levels in vitreous fluid in eyes with regression, stabilization, and progression were analyzed by analysis of variance. The effects of VEGF levels in vitreous fluid on PDR were analyzed by analysis of variance. The mean VEGF level of vitreous was (592.4801 +/- 587.4267) ng/L in PDR patients, and it was (131.3022 +/- 26.9192) ng/L in normal control. VEGF level was significantly higher in PDR patients than that in normal control (t = 3.2315, P < 0.05). There were 10 eyes (20%) with progression of PDR, 10 eyes (20%) with stabilization, and 30 eyes (60%) with regression. Vitreous level of VEGF was significantly higher in eyes with progression of PDR than that in eyes with stabilization or regression of PDR (q = -3.3187, -4.0843; P < 0.05). Vitreous level of VEGF was significantly higher in eyes without retinal photocoagulation than that in eyes underwent panretinal photocoagulation or local photocoagulation (q = -4.2187, -3.9672; P < 0.05). There is a correlation between the expression of VEGF of vitreous and the severity of PDR. The expression of VEGF of vitreous presents a relatively lower level in patients with stabilization and regression of PDR.

Aqueous humor level of sCD44 in patients with degenerative myopia and primary open-angle glaucoma

The transmembrane glycoprotein CD44 is a major hyaluronan cell surface receptor widely distributed in eye tissues and fluids. The shed ectodomain of CD44 is termed soluble CD44 and is toxic to human retinal ganglion cells in cell culture. The purpose of this study was to investigate the concentration of sCD44 in the aqueous humor (AH) of normal subjects, patients with primary open-angle glaucoma, and patients with degenerative myopia but without glaucoma, to determine if the molecule might serve as a protein marker of glaucoma. In this case-control study, AH samples were collected from controls (n = 16), patients with primary open-angle glaucoma (n = 11), and patients with degenerative myopia (n = 11) who underwent phacoemulsification surgery to treat mature or immature cataracts. The sCD44 concentration in AH was measured using a commercial ELISA kit. In normal AH samples the sCD44 concentration was 5.40 +/- 1.21 ng/mL, whereas in degenerative myopia patients the sCD44 concentration was 5.76 +/- 1.15 ng/mL. There was thus no statistically significant difference between these two groups (p > 0.05). The aqueous sCD44 concentration in patients with primary open-angle glaucoma (12.2 +/- 10.1 ng/mL) was higher than that of the control group (p < 0.05). sCD44 may be a protein marker of primary open-angle glaucoma.

The temperature-sensitive mutants of Toxoplasma gondii and ocular toxoplasmosis

The risk of blindness caused by ocular toxoplasmosis supports efforts to improve our understanding for control of this disease. In this study, the involvement of CD8 +, CD4 +, B cell, and IL-10 gene in the immune response of primary ocular infection with the temperature-sensitive mutant (ts-4) of the RH Toxoplasma gondii strain, and in the protective immunity of ocular ts-4 vaccination and challenge with RH strain was investigated in murine models utilizing inbred C57BL/6 mice-deficient in CD4 +, CD8 +, B cells (μMT), or IL-10 gene. Compared to naive mice, all WT and mutant mice had different degree of ocular pathological changes after ts-4 ocular infection, in which both CD8 KO and IL-10 KO mice showed the most severe ocular lesions. Immunized by ts-4 intracameral (i.c.) inoculation, all mutant mice had partially decreased vaccine-induced resistance associated with increased ocular parasite burdens after RH strain challenge. A significant increase of the percentages of B cells and CD8 + T cells in the draining lymph nodes were observed in WT and IL-10 KO mice after either infection or challenge. The levels of specific anti-toxoplasma IgG in both eye fluid and serum from all the mice were significantly increased after ts-4 i.c. immunization, except μMT mice. These results suggest that the avirulent ts-4 of T. gondii inoculated intracamerally can induce both ocular pathology and ocular protective immunity; CD4 +, CD8 +, B cell, and IL-10 gene are all necessary to the vaccine-induced resistance to ocular challenge by virulent RH strain, in which CD8 + T cells are the most important component.

Detecção da resistência a antibióticos de bactérias isoladas de casos clínicos ocorridos em animais de companhia

The identification of different bacterial strains and the occurrence of antibiotic resistance were investigated in several infection processes of pets as skin abscess with purulent discharge, bronco alveolar fluid, earwax, urine, mammary, and eye fluid. Streptococcus spp. and Staphylococcus spp. were the most detected in the different samples. A high frequency of antimicrobial resistance has been observed and this could reflect the wide use of antimicrobials in pets, making the effectiveness of antibiotic treatment to become more complicated.

Intraocular pharmacokinetics of intravenously administered marbofloxacin in rabbits with experimentally induced acute endophthalmitis

To compare penetration of IV administered marbofloxacin in intraocular fluids of healthy and inflamed eyes in rabbits with endotoxin-induced endophthalmitis. 35 pigmented rabbits. Endophthalmitis was induced in the right eye via intravitreal administration of Escherichia coli endotoxin. The left eye was a control eye. After 24 hours, a single dose of marbofloxacin (4 mg/kg, IV) was administered. Groups of rabbits (n = 5/group) were euthanized 0.5, 1, 2, 4, 6, 10, and 18 hours later, and blood and ocular fluids were collected. Marbofloxacin concentrations were determined via reverse-phase high-performance liquid chromatography, and pharmacokinetic analysis of the data was performed with a mono-compartmental model. Mean area under the aqueous concentration-time curve was significantly lower in control eyes (1.64 +/- 0.07 microg*h/mL) than in inflamed eyes (3.31 +/- 0.11 microg*h/mL). Similarly, drug penetration into aqueous humor was 33% and 65% for control eyes and inflamed eyes, respectively. Mean area under the vitreous humor concentration-time curve for control eyes(1.75 +/- 0.05 microg*h/mL) was significantly less than for inflamed eyes (2.39 +/- 0.16 microg*h/mL). In the vitreous humor, corresponding penetrations were 34% and 47%, respectively. Penetration of marbofloxacin into the aqueous and vitreous humor after IV administration was significantly enhanced by intraocular inflammation, suggesting a role for this antimicrobial in the prophylaxis or treatment of bacterial endophthalmitis caused by susceptible pathogens.

Seminal Plasma Lipocalin-Type Prostaglandin D Synthase: A Potential New Marker for the Diagnosis of Obstructive Azoospermia

We examined the relationship between L-PGDS (lipocalin-type prostaglandin D synthase) levels in seminal plasma and the presence or absence of obstruction in the male seminal tract. Semen samples were collected and analyzed from 1) 10 patients with normal semen parameters, 2) 9 with obstructive azoospermia, 3) 20 after vasectomy and 4) 14 with nonobstructive azoospermia. Seminal L-PGDS was measured using an enzyme-linked immunosorbent assay technique. We found that seminal plasma L-PGDS in the groups with obstruction was significantly lower than in any of the other groups (p <0.001). Using a cutoff of 100 microg/l all men with obstructive azoospermia had L-PGDS less than 100 microg/l, while none with normal sperm parameters did. Men with nonobstructive azoospermia had less homogeneity of L-PGDS levels, including 29.6% with L-PGDS more than 100 microg/l. Our results suggest that seminal L-PGDS level can potentially be a biomarker for assessing patency in the seminal tract in men with azoospermia. In men with azoospermia and high seminal L-PGDS (more than 100 microg/l) the diagnosis of nonobstructive azoospermia can be potentially made without biopsy. Our study shows that using semen L-PGDS levels provides a diagnosis of nonobstructive azoospermia in almost 30% of these men.

Influence of Surface Fluid during Photorefractive Keratectomy Using a 213-nm Solid-State Laser

Purpose: To investigate the effect of surface fluid on the ablation rate and efficacy of 213-nm solid-state laser during photorefractive keratectomy (PRK). Methods: Twelve rabbits (24 eyes) underwent myopic PRK for the correction of 10 diopters using 213-nm solid-state laser. Photoablation was performed with removal of corneal surface fluid using the Weckcel® sponge every 5 seconds in one eye and without removal of corneal surface fluid in the control eye. The mean central corneal thickness (CCT) was evaluated preoperatively, and at 1 week, 4 weeks postoperatively. Results: The mean CCT of group 1 (with removal of corneal surface fluid) were 361.3±13.9 µm preoperatively and 321.4±18.5 µm at 4 weeks postoperatively. The mean CCT of group 2 (without removal of surface fluid) were 358.7±8.9 µm preoperatively and 338.4±12.0 µm at 4 weeks postoperatively. The mean ablation depths were 39.8±7.4 µm in group 1 and 20.3±5.8 µm in group 2 at 4 weeks postoperatively (p

Choroiditis in a Patient with Multiple Sclerosis

Purpose: To describe choroiditis in multiple sclerosis (MS). Design: Case report. Methods: Clinical findings, fluorescein angiography, optical coherence tomography, and treatment are presented. A 50-year-old man with MS presented with vitritis and multiple choroidal lesions in the fovea and periphery in both eyes. Fluorescein angiography (FA) revealed early hyperfluorescence and late leakage of the lesions. Optical coherence tomography showed subretinal fluid in the right eye. One month post-treatment, visual acuity returned to the baseline with complete resolution of subretinal fluid and decreased leakage on FA. Conclusions: Choroiditis might be related to MS, but may also be a chance occurrence.

Picoliter viscometry using optically rotated particles

Important aspects in the field of microrheology are studies of the viscosity of fluids within structures with micrometer dimensions and fluid samples where only microliter volumes are available. We have quantitatively investigated the performance and accuracy of a microviscometer based on rotating optical tweezers, which requires as little as one microliter of sample. We have characterized our microviscometer, including effects due to heating, and demonstrated its ability to perform measurements over a large dynamic range of viscosities (at least two orders of magnitude). We have also inserted a probe particle through the membrane of a cell and measured the viscosity of the intramembranous contents. Viscosity measurements of tears have also been made with our microviscometer, which demonstrate its potential use to study unstimulated eye fluid.

Acute retinal ganglion cell injury caused by intraocular pressure spikes is mediated by endogenous extracellular ATP

Elevated intraocular pressure may lead to retinal ganglion cell injury and consequent visual deficits. Chronic intraocular pressure increase is a major risk factor for glaucoma, a leading blinding disease, and permanent visual deficits can also occur following acute pressure increments due to trauma, acute glaucoma or refractive surgery. How pressure affects retinal neurons is not firmly established. Mechanical damage at the optic nerve head, reduced blood supply, inflammation and cytotoxic factors have all been called into play. Reasoning that the analysis of retinal neurons soon after pressure elevation would provide useful cues, we imaged individual ganglion cells in isolated rat retinas before and after short hydrostatic pressure increments. We found that slowly rising pressure to peaks observed in trauma, acute glaucoma or refractive surgery (50-90 mmHg) did not damage ganglion cells, whereas a rapid 1 min pulse to 50 mmHg injured 30% of these cells within 1 h. The severity of damage and the number of affected cells increased with stronger or repeated insults. Degrading extracellular ATP or blocking the P2X receptors for ATP prevented acute pressure-induced damage in ganglion cells. Similar effects were observed in vivo. A short intraocular pressure transient increased extracellular ATP levels in the eye fluids and damaged ganglion cells within 1 h. Reducing extracellular ATP in the eye prevented damage to ganglion cells and accelerated recovery of their response to light. These data show that rapid pressure transients induce acute ganglion cell injury and unveil the causal role of extracellular ATP elevation in such injury.

Protothecosis in 17 Australian dogs and a review of the canine literature

Systemic protothecosis was diagnosed in 17 Australian dogs between 1988 and 2005. There was a preponderance of young-adult (median 4 years), medium- to large-breed dogs. Females (12/17 cases) and Boxer dogs (7 cases, including 6 purebreds and one Boxer cross) were over-represented. Sixteen of 17 dogs died, with a median survival of four months. A disproportionate number of cases were from coastal Queensland. In most patients, first signs were referable to colitis (11/17 cases), which varied in severity, and was often present for many months before other symptoms developed. Subsequent to dissemination, signs were mostly ocular (12 cases) and/or neurologic (8 cases). Two dogs had signs due to bony lesions. Once dissemination was evident, death or euthanasia transpired quickly. Prototheca organisms had a tropism for the eye, central nervous system (CNS), bone, kidneys and myocardium, tissues with a good blood supply. Microscopic examination and culture of urine (5 cases), cerebrospinal fluid (CSF;1 case), rectal scrapings (4 cases), aspirates or biopsies of eyes (5 cases) and histology of colonic biopsies (6 cases) as well as skin and lymph nodes (2 cases) helped secure a diagnosis. Of the cases where culture was successful, P wickerhamii was isolated from two patients, while P zopfii was isolated from five. P zopfii infections had a more aggressive course. Treatment was not attempted in most cases. Combination therapy with amphotericin B and itraconazole proved effective in two cases, although in one of these treatment should have been for a longer duration. One surviving dog is currently still receiving itraconazole. Protothecosis should be considered in all dogs with refractory colitis, especially in female Boxers.

Intraocular Fluid-Air Exchange Reduces Retinal Ganglion Cell Activity

Aim: To demonstrate the influence of intraocular fluid-air exchange on retinal ganglion cell activity. Methods: In two cats lensectomy and vitrectomy were performed in a two-step approach 2 weeks prior to recording experiments. To measure retinal activity, up to two fiber microelectrodes were inserted via a scleral port. Precise micromanipulator positioning of the electrodes’ tips onto the inner retinal surface were verified by ophthalmoscopy and simultaneous electrical recording. Neuronal activity of the retina was continuously recorded with or without visual stimulation. We maintained the intraocular pressure constant at 29 mm Hg. Fluid-air exchange and fluid refill were performed with an infusion tube integrated in the manipulator and slowly to avoid direct mechanical/stream-based damage of the retina. Results: We found that fluid-air exchange leads to a rapid reduction of spontaneous as well as visually evoked retinal ganglion cell activity. The activity started to diminish within few minutes, and then it halved approximately every 3 min. Even 1 h after eye fluid refill, the retinal activity recovered only partially. Conclusion: Decrease in retinal activity after fluid-air exchange can be explained by mechanical stress-induced drying of the inner retinal surface and by potential changes of extracellular ion concentration. Since even moderate airstream-based fluid-air exchanges can lead to retinal damage, the surgeon should minimize the quantity of air passing open sclerotomy sites until a better understanding of the retinal effects of this essential technique in modern vitrectomy is available.

Intracranial migration of silicone oil from an eye with optic pit

The origin of subretinal fluid in eyes with optic pit remains controversial. Case report. The authors found that silicone oil, implanted into an eye that developed proliferative vitreoretinopathy after surgery for optic pit-related macular detachment, has migrated into the subarachnoid space. As this case shows, cerebrospinal fluid may migrate into the submacular space in eyes with optic pits.

Anti-TNF therapies in the management of acute and chronic uveitis

Patients with anterior uveitis may be treated with topical therapy alone but patients with posterior uveitis and those with sight threatening complications of anterior uveitis usually require systemic treatment especially if the disease is bilateral. The mainstay of treatment is corticosteroids and additional immunosuppressive agents such as cyclosporin and mycophenolate are used when necessary. There remains a significant cohort of patients in whom this therapy is either not tolerated or is ineffective. The use of the anti-tumour necrosis factor (TNF) antibodies has been very successful in controlling other immune-mediated disorders such as rheumatoid arthritis and has subsequently been extended to use in other arthritidies and other disorders such as psoriasis and Crohn's disease. TNF is known to play a key role in ocular inflammation as shown by animal studies and its detection in the ocular fluids of inflamed eyes in man. In some disorders all types of anti-TNF antibodies have similar efficacy but that does not appear to be the case with uveitis where infliximab is at present looking to be more effective than etanercept. The data on the use of anti-TNF drugs in uveitis is presented together with new data on its role as a steroid sparing agent.