A study was performed to detect the presence of polycyclic aromatic hydrocarbons (PAHs) in bovine eyes. Twenty fresh bovine eyes were used to detect the presence of PAHs in lens, vitreous and aqueous by HPLC and spectrofluorometer. In lenticular tissue the mean amount of PAHs was 0.0271 microgram/g and the mean level of PAH in each lens was 0.059 microgram. Five types of PAHs (pyrene, fluoranthene, triphenylene, 1.2-benzanthracene and chrysene) were found in the lenses but none in vitreous and aqueous. These data indicate that PAHs are present only in the lens of the bovine eye. The source of these substances in mammalian clear lens is unclear.

Animals↗

PubMed1996

Macular recovery time in diabetic children without retinopathy.

The aim of this study was to evaluate whether patients with initial diabetic nephropathy (defined as persistent microalbuminuria) have an impairment of macular recovery time and if this impairment changes in a long-term follow-up. Eighty insulin-dependent diabetic children without fluorescein angiographic signs of retinopathy and 80 controls were included in the study. All patients underwent nyctometry at the beginning of the study; diabetic children repeated the same test after 7 years. Diabetics were divided into two subgroups as regards presence of persistent microalbuminuria (albumin excretion rate > 20 micrograms/min/1.73 m2). At the beginning of the study, diabetics as a whole and normoalbuminuric patients showed similar data to controls, while microalbuminuric ones showed worse data at nyctometry (initial recovery time (IRT): 44.89 +/- 12.50; Summation method (SM): 509.1 +/- 312.0) in comparison with normoalbuminuric (IRT: 38.12 +/- 10.31, P = 0.010; SM 648.6 +/- 272.2, P = 0.036) and control subjects (IRT: 37.77 +/- 11.82, P = 0.004; SM: 661.5 +/- 297.5, P = 0.013). After 7 years, normoalbuminuric subjects showed a slight, but not significant worsening of nyctometry, while in microalbuminuric ones a significant difference between baseline and the end of follow-up was found (IRT: 44.89 +/- 12.50 vs. 52.91 +/- 13.9, P < 0.01; SM: 509.1 +/- 312.0 vs. 374.8 +/- 271.9, P < 0.05). Diabetic patients had a higher rate of abnormal IRT and SM than controls (P = 0.0004 and P = 0.0006, respectively). A higher number of patients in microalbuminuric subgroup than in normoalbuminuric one were found (both at baseline and at the end of follow-up) above the 95th centile of IRT (baseline 3 vs. 15; P = 0.0002; end of follow-up 5 vs. 23; P < 0.0001) and below the 5th centile of SM (baseline 5 vs. 14; P = 0.004; end of follow-up 5 vs. 19; P < 0.0001). Nyctometry was found more altered in microalbuminuric patients than in normoalbuminuric and controls. Unfortunately, there is a large overlap between the two diabetic subgroups and between diabetics and controls; for this reason, this technique is not suited for everyday practice.

Adolescent↗

PubMed1996

The ability of bacteria to use Na-hyaluronate as a nutrient.

The objective of this study was to test bacteria ability to use Na-hyaluronate as a nutrient in vitro. Thirteen bacteria strains were tested in three different media: specific culture medium, agar-Healon medium and agar-Healon GV medium. The bacterial growth criteria were determined by counting the number of new colonies appearing at each observation time (0, 24, 48 and 72 h). The results were expressed as the percentage of growth in agar-Na-hyaluronate compared to each corresponding specific culture medium. After 24 h in the medium containing agar-Healon, S. aureus, S. epidermidis, S. pyogenes and S. viridans grew using hyaluronic acid as a nutrient. The percentage of growth of these species remained constant over the follow-up period. The other bacteria strains tested were unable to use Healon as a nutrient. After 24 h of incubation in the medium containing agar-Healon GV, S. aureus, S. epidermidis, S. pyogenes, and S. viridans exhibited about 20% growth. Subsequently, this percentage slowly increased to about 50%. The other bacteria stains tested were unable to employ Healon GV as a nutrient. With the exception of Staphylococci and Streptococci, the other species do not synthesize the necessary enzymes to break glucosidic bonds, therefore neither concentration of hyaluronic acid can be utilized as a source of carbohydrate for their survival in culture media.

Bacteria↗

PubMed1996

Long term results of intraoperative mitomycin C in the treatment of recurrent pterygium.

AIM: The study was designed to evaluate the long term results of intraoperative mitomycin C in patients with one recurrence of pterygium. METHODS: In 45 white patients with one recurrence of pterygium the 'bare sclera technique' was performed and a sterile sponge soaked in a 0.2 mg/ml (0.02%) mitomycin C solution was placed intraoperatively on the sclera for 3 minutes. The control group underwent surgical excision only. Recurrences were analysed by the chi 2 test and the method of Kaplan-Meier (life table analysis); the difference between survival curves was tested by the log rank test. The chi 2 test with Yates's correction or Fisher's exact test were used to analyse the difference in complications and side effects between the two groups. RESULTS: After a mean postoperative follow up of 34.55 (SD 13.70) months, 6 recurrences (12.5%) were observed in the mitomycin C treated patients and 16 (35.6%) in the control patients (p = 0.027). The 24 and 48 month life table success rates were 89% and 83% in the mitomycin C treated group and 66% and 63% in the control group, respectively (p = 0.022). No severe side effects appeared during follow up. Superficial punctate keratitis appeared in the early postoperative period in only seven mitomycin C treated eyes (15.5%) (p = 0.018). CONCLUSION: This study confirms the efficacy of intraoperative mitomycin C in improving the success rate after recurrent pterygium surgical excision.

Adult↗

PubMed1996

Effect of dapiprazole, an alpha-adrenergic blocking agent, on aqueous humor dynamics in pigmentary glaucoma.

PURPOSE: In this investigation the authors studied the effect of dapiprazole, an alpha-adrenergic blocking agent, on aqueous humor dynamics in patients affected with pigmentary glaucoma. METHODS: Dapiprazole 0.5% eye drops were administered 3 times daily as adjunctive therapy to 16 pigmentary glaucoma patients in addition to timolol 0.5% eye drops twice daily. Computerized tonography was performed before and 3, 12 and 36 months after dapiprazole treatment. Sixteen sex- and age-matched pigmentary glaucoma patients treated with timolol 0.5% eye drops alone were used as a control group. RESULTS: After 36 months of follow-up, the dapiprazole-treated group showed a significant increase in total outflow facility (C, from 0.17 +/- 0.04 to 0.22 +/- 0.07 ml min-1 mm Hg-1; p = 0.010, paired t test) and Po/C ratio (Q) significantly decreased from 113.39 +/- 31.02 to 89.22 +/- 51.66 (p = 0.036, paired t test). CONCLUSIONS: Our results show that the introduction of dapiprazole in the therapy of pigmentary glaucoma may be useful in the long-term management of these patients. Its mechanism of action is likely to be due to iridoplegia; in fact, a decrease in the shedding of pigment occurs, with time, the outflow facility increases and the pigment clearance from the trabecular meshwork is enhanced.

Administration, Topical↗

PubMed1996

Long-term results of Krupin-Denver valve implants in filtering surgery for neovascular glaucoma.

The long-term results obtained with the Krupin eye short valve shut in 28 eyes with neovascular glaucoma were retrospectively analyzed by means of Kaplan-Meier survival curve. The preoperative intraocular pressures (IOPs) ranged from 28 to 62 mm Hg (mean, 36.8 +/- 5.8 mm Hg). Success was considered an IOP of less than 22 mm Hg and greater than 5 mm Hg without medication (complete success) or with medication (qualified success) without additional glaucoma filtering surgery or devastating complications. Postoperative success was obtained in 10 out of 28 eyes after a mean follow-up period of 58.4 +/- 23.02 months (range, 10-108 months). The 3- and 6-year life table success rates were 66 and 34%, respectively. Early complications were: shallow or flat anterior chamber (15 patients, 53.6%), hypotony (16 patients, 57.1%), hypertony (7 patients, 25%), serous choroidal effusion (7 patients, 25%), fibrinous uveitis (5 patients, 17.9%), blockage of the intracameral portion of the tube by fibrin (5 patients, 17.9%), choroidal hemorrhage (2 patients, 7.1%). Late complications were: external conjunctival bleb failure (12 patients, 42.9%), blockage of the intracameral portion of the tube by fibrovascular tissue (5 patients, 17.9%), cataract (2 patients, 7.1%), bullous keratopathy (2 patients, 7.1%), external erosion of the Silastic valve (2 patients, 7.1%), phthisis bulbi (2 patients, 7.1%). Mortality during long-term follow-up was high in our series. The complications of an underlying diabetes mellitus were the most common cause of death (15 out of 22 patients). The high mortality of patients subjected to valve implantation makes it difficult to interpret the results of long-term studies. However, the valve implant is still today an alternative surgical procedure for controlling IOP in eyes with neovascular glaucoma that have visual potential.

Aged↗

PubMed1996

The usefulness of dapiprazole, an alpha-adrenergic blocking agent, in pigmentary glaucoma.

The aim of this study was to increase understanding of the usefulness of an alpha-adrenergic blocking agent, dapiprazole 0.5% eyedrops, as an adjunct in antiglaucomatous therapy for 20 patients with pigmentary glaucoma receiving timolol 0.5% and pilocarpine 1%. After 12 months of dapiprazole treatment, the difference from the pretreatment mean intraocular pressure (IOP) value was statistically significant (P = .005). After 12 and 36 months of treatment, an hour-to-hour comparison of diurnal IOP curve values showed a statistically significant difference in all cases (P < .001). Although further investigations may be necessary to reach a definite conclusion, dapiprazole appeared to have a beneficial, stable in time effect in these patients.

Administration, Topical↗

PubMed1996

Tear deficiency in Fuchs' intermediate uveitis.

OBJECTIVE: To assess quantitatively and qualitatively tear secretion in Fuchs' intermediate (heterochromic) uveitis to detect any possible anomaly linked to Fuchs' uveitis. DESIGN: Prospective study. SETTING: University eye clinic, Chieti, Italy. PATIENTS: Thirty consecutive white patients aged 32 to 65 years with unilateral Fuchs' heterochromic uveitis. OUTCOME MEASURES: Results of Schirmer's test I, tear film breakup time, conjunctival mucus ferning. RESULTS: Schirmer's test I showed a tear deficiency in 15 patients; the tear film breakup time and ferning were abnormal in these patients. There was a significant difference in the test results between the affected eyes and the fellow, unaffected eyes (p < 0.001). There was no relation between tear deficiency and age. CONCLUSIONS: The presence of tear anomalies only in the affected eye of patients with Fuchs' heterochromic uveitis suggests a link between Fuchs' uveitis and tear deficiency.

Adult↗

PubMed1994

Aqueous misdirection syndrome: a complication of neodymium: YAG posterior capsulotomy.

A 50-year-old, white, pseudophakic man who had a neodymium:YAG (Nd:YAG) posterior capsulotomy for capsule opacification developed a persistent rise in intraocular pressure (IOP) associated with a flat anterior chamber. Full-thickness patent iridotomy performed with an Nd:YAG laser did not reduce IOP. A-scan ultrasonography showed aqueous pockets in the vitreous, leading to a diagnosis of malignant glaucoma. Medical therapy comprising atropine, phenylephrine, mannitol, and acetazolamide normalized IOP and resolved the clinical findings.

Anterior Chamber↗

PubMed1994

Effectiveness of intraoperative mitomycin C in the treatment of recurrent pterygium.

The effectiveness of intraoperative administration of mitomycin C and the occurrence of postoperative complications have been evaluated in 30 white patients with one recurrence of pterygium. The authors employed the 'bare-sclera technique' and, intraoperatively, placed in the episcleral space for 3 min a sterile sponge soaked in a 4% mitomycin C solution. The control group (30 patients with one recurrent pterygium) underwent only surgical excision. Statistical analysis performed using the chi-square test showed a significant (p = 0.024) reduction of recurrences of pterygium in the group treated intraoperatively with mitomycin C. No heavy side effects occurred during the follow-up period. Mitomycin C, administered intraoperatively, may be considered an effective treatment to improve the success rate after surgical excision.

Adult↗

PubMedDate not supplied

The effectiveness of dapiprazole in preventing exercise-induced IOP increase in patients with pigmentary dispersion syndrome.

PURPOSE: The authors investigated the use of dapiprazole, an alpha-adrenergic blocking agent, in preventing pigment release and IOP increase after exercise in patients affected with PDS. METHODS: Three young myopic males (31, 34 and 35 years old) affected with pigmentary dispersion syndrome performed 30 minutes of jogging on a computerized treadmill. Telemetric heartbeat measurement was performed to obtain constant pulse rate training. Computerized tonography and IOP measurement were performed 10 minutes after the exercise. After one month the patients repeated the same exercise after pre-treatment with dapiprazole 0.5% eyedrops (one drop 30, 20 and 10 minutes before the exercise). Ten minutes after the exercise IOP measurements and computerized tonography were repeated. RESULTS: After 30 minutes of exercise IOP measurements showed values ranging from 19 to 45 mmHg (mean 30.33; SD 8.73). Computerized tonography C values after exercise ranged from 0.04 to 0.16 (mean 0.09; SD 0.04). After pre-treatment with dapiprazole 0.5% eyedrops, IOP values ranged from 18 to 28 mmHg (mean 23.33; SD 3.44) and tonography C values ranged from 0.10 to 0.20 (mean 0.14; SD 0.03). CONCLUSIONS: The study supports the concept that exercise-induced pigment release temporarily obstructs the acqueous outflow channels, causing IOP increase in some patients with PDS. Pre-treatment with dapiprazole was useful in reducing IOP spikes and in increasing tonographic total outflow facility after exercise. The absence of induced myopia and the lack of dangerous vitreoretinal tractions on retinal periphery make dapiprazole a safe method to reduce exercise-induced pigment dispersion.

Administration, Topical↗

PubMedDate not supplied

Reproducibility of nerve fiber layer thickness measurements using optical coherence tomography in silicone oil-filled eyes.

PURPOSE: To evaluate the reproducibility of nerve fiber layer (NFL) thickness measurements by optical coherence tomography (OCT) in individuals with silicone oil-filled eyes. METHODS: Eighteen patients who had undergone pars plana vitrectomy and silicone oil tamponade for retinal detachment were enrolled in a prospective, case-controlled clinical study. Each patient underwent OCT measurement of NFL thickness. Five repetitions of a series of scans on five separate occasions within a 0.5-month period were performed. Each eye was scanned at two different nerve head programs [radius (R) = 1.5 and R = 1.73]. The contralateral healthy eye was used as control. For each option (R = 1.5 and R = 1.73) and region (superior, inferior, temporal, nasal and overall mean), variance components and intraclass correlation coefficients (ICCs) were determined using repeated-measures regression. In these models, NFL thickness, as measured by OCT, was considered to have three variance components: intersubject, intervisit (within subject, between dates), and intravisit (within subject, within date). The ICC (intersubject variance/total variance) was used as a measure of reliability. RESULTS: The contralateral healthy eye provided a higher degree of reproducibility than the silicone oil-filled eye (p = 0.0001). Reproducibility was higher in a given eye on a given visit than from visit to visit. Reproducibility as measured by ICCs was as follows: R = 1.5, 0.54/0.30 (control eyes/silicone oil-filled eyes); R = 1.73, 0.51/0.30. CONCLUSIONS: Reproducibility results for OCT measurement of NFL thickness are different in healthy eyes and silicone oil-filled eyes. NFL thickness measurement is not reliable in silicone oil-filled eyes.

Case-Control Studies↗

PubMedDate not supplied

Management of scleral rupture during retinal detachment surgery: a case report.

PURPOSE: Rupture of the sclera occurring during retinal detachment surgery is generally associated with unfavourable anatomic and visual outcomes. Re-operation after a failed scleral buckle procedure and pre-existing scleral thinning are considered the main risk factors for scleral rupture. CASE REPORT: We describe the management and the favourable outcome of a case of scleral rupture in a 71-year-old woman during re-operation for retinal detachment. CONCLUSIONS: We managed this case of scleral rupture in accordance with current indications concerning the anatomical recovery, by scleral suture and patch graft, restoring IOP by gas tamponade. The positive outcome was partly related to the prompt closure of the retinal hole which led to reattachment, and partly to favourable events such as the moderate intensity of vitreous hemorrhage and the lack of any more serious intraoperative and postoperative complications.

Aged↗

PubMedDate not supplied

Optical coherence tomography and retinal thickness analyzer features of spontaneous resolution of vitreomacular traction syndrome: a case report.

PURPOSE: To report optical coherence tomography (OCT) and retinal thickness analyzer (RTA) findings in a case of spontaneous resolution of vitreomacular traction syndrome. METHODS: Qualitative and quantitative analysis of the macular region was performed with OCT and RTA. RESULTS: In the left eye of a 34-year-old woman with blurred vision, OCT and RTA examination showed a discrete linear signal anterior to the retina with attachment at the macula and secondary cystoid macular changes. OCT and RTA examination showed an increase in macular thickness (350 microm). Six months later the patient showed a spontaneous complete recovery of visual acuity. Vitreomacular traction and cystoid changes were no longer detectable at OCT and RTA examination; retinal thickness was normal (205 microm) and a posterior vitreous detachment was visible. CONCLUSIONS: Both OCT and RTA were useful tools for making the diagnosis of vitreomacular traction syndrome and demonstrating the effect of spontaneous vitreomacular traction release with resolution of cystoid macular changes.

Adult↗