Effects of an antioxidant protective topical formulation on eye exposed to ultraviolet-irradiation: a study in rabbit animal model.

Ultraviolet-radiation exerts a well-known role in the development of various ocular diseases and may contribute to the progress of age-related macular degeneration. Therefore, the use of compounds able to protect the eyes from UV-induced cellular damage is challenging. The aim of this study has been to test the protective effects of an antioxidant topical formulation against UV-induced damage in rabbit eyes. Twelve male rabbits were used. Animals were divided into 4 groups of 3 animals each. Control group (CG) did not receive any irradiation and/or eye drop. The other three experimental groups were treated as follows: the first group received only UVR irradiation for 30 min, without eye drop supplementation (Irradiation group, IG), the second (G30) and the third (G60) groups received UV irradiation for 30' and 60', respectively, and eye drop supplementation (riboflavin, d-alpha-tocopheryl polyethylene glycol, proline, glycine, lysine and leucine solution) every 15 min for three hours. In the IG group a significant increase of oxidized glutathione (GSSG) and hydrogen peroxide (H(2)O(2)) was recorded in the aqueous humor, whereas ascorbic acid levels were significantly lower when compared to control eyes. In the groups exposed to UVR rays for 30 min, and treated with the topical antioxidant formulation, the GSSG, H(2)O(2) and ascorbic acid levels were similar to those recorded in controls, whereas in the G60 group the three markers significantly differ from control group. In the lens, a significant decrease of alpha tocopherol and total antioxidant capacity (TAC) was recorded in IG-animals as compared to control group, whereas malondialdehyde (MDA) levels were significantly higher in UV-induced eye than in control eyes. In the G30 groups the alpha tocopherol, MDA and TAC levels do not significantly differ from those recorded in controls, whereas in the G60 group these three markers significantly differ from control group. Present findings demonstrate that topical treatment with the antioxidant formulation used herein protects ocular structures from oxidative stress induced by UV exposure in in vivo animal model.

[Adequacy and reliability of orthoanalyzer Ergovision for job-fitness evaluation]. / Adeguatezza e affidabilità dell'ortoanalizzatore Ergovision nel giudizio di idoneità specifica.

The aim of this research was to evaluate the Ergovision Screener (ES) accuracy e validity by a confrontation with the conventional ophthalmic check (OC), for the medical evaluation of job fitness. A population of 100 VDU operators was considered. Each subject underwent randomly both the ES and the ophthalmic check visit. Several test carried out by the Ergovision Screener were not consistent with the conventional ophthalmic check. In a number of cases, high false positive ratio have been found, which could lead to unnecessary further examinations. For all these reasons we believe that the ES is not an appropriate instrument for the medical evaluation of job fitness.

[Work efficiency and lighting conditions: an experimental study]. / Efficienza lavorativa e condizioni illuminotecniche: studio sperimentale.

Thirty-two voluntary subjects were selected, not suffering either from any degenerative ophthalmic diseases or refraction and ocular motility alterations. Each subject underwent close visual task experimental sessions (e.g. PC usage), under monitored experimental conditions. Aim of the study is the assessment of working efficiency effects caused by lighting conditions characterized by "according to law" illuminations, yet in presence of high or low luminance ratios in the occupational visual field". An analysis of the data showed that high luminance ratios conditions show a decrease of the performance (decrease overall efficiency, increase in the number of errors and time of execution), which where not detected with low luminance ratios conditions. Asthenopia did not show clear differences, possibly due to the effects of the intense near work which was present in both the experimental sessions.

Eye complaints in the office environment: precorneal tear film integrity influenced by eye blinking efficiency.

To achieve a common base for understanding work related eye complaints in the office environment, it is necessary to merge approaches from indoor air science, occupational health, and ophthalmology. Based on database searches, it is concluded that precorneal tear film (PTF) alteration leads to eye complaints that may be caused by: (1) thermal factors (low relative humidity; high room temperature); (2) demanding task content (attention decreases blinking and widens the exposed ocular surface area); and (3) individual characteristics (for example, tear film alterations, blinking anomalies, gland dysfunctions, and use of contact lenses). These factors and conditions are able to progressively increase water evaporation and faster thinning of the PTF, which causes dryness and dry spot formation on the cornea, possibly followed by corneal and conjunctiva epithelial alterations and eye complaints. Another possible cause of eye complaints is certain irritating chemical compounds, in addition to oxidation mixtures that are formed in reactions between ozone and unsaturated organic compounds (alkenes). The effect may be exacerbated by low relative humidity.

Observation distance and blinking rate measurement during on-site investigation: new electronic equipment.

Modern work activities often require an intense and prolonged visual effort on near objects. At the same time, occupational asthenopia caused by accommodation and binocularity overloading is a very common complaint in these working populations. Moreover, blinking rate seems to be a sensitive parameter with 'indoor-near-work operators', possibly increased by both chemical and physical environmental agents and decreased by cognitive effort. In this paper, a new piece of electronic equipment used to measure the observation distance and blinking rate is described.

Glaucoma after vitreo-retinal surgery with silicone oil injection: epidemiologic aspects.

PURPOSE: To evaluate the prevalence of glaucoma after pars plana vitrectomy with silicone oil injection and to determine the different clinical forms. METHODS: Authors have carried out a retrospective longitudinal study on patients who underwent pars plana vitrectomy with silicone oil injection from 1981 to 1995. The examined population consists of 301 patients (301 eyes), with an age ranging from 8 to 85 years, affected by retinal detachment and proliferative vitreoretinopathy. RESULTS: The prevalence of the secondary glaucoma has been 18.5%. In all cases glaucoma was caused by trabecular meshwork obstruction due to silicone oil emulsification. The glaucoma has been more frequent after surgery for recurrent rhegmatogenous retinal detachment with fibrous PVR (52.86%) and for particular forms of rhegmatogenous retinal detachment (giant tears, multiple breaks, pseudophakia) with incipient PVR (30%). CONCLUSION: Glaucoma after intravitreal silicone oil injection for complicated retinal detachments is a relatively frequent complication mostly when surgery needs endophotocoagulation, endodiatermy and lensectomy.

Posterior vitreous detachment and work efficiency: a case study.

The paper analyses a case report of a female worker whose job required prolonged near visual effort and who suffered from multiple ophthalmological disorders. The specific case of interaction between the visual apparatus of the operator and the tasks performed is discussed, with particular reference to the unstable compensation that different pathological disorders, when summed together, can produce, thus allowing to subjects to lead a normal working and social life for long periods of time without any limitations and without any significant asthenopic symptoms. Because this compensation is unstable, it can unexpectedly be impaired due to the onset of diseases not involving the visual apparatus. The scientific literature was analysed in order to assess, at least approximately, the prevalence of clinical/functional situations identical or similar to the case described.

Trends in cataract surgery in Milan (Italy) from 1956 to 1987. Relationship to age and visual acuity.

In order to test whether the mean age at cataract surgery has changed over the course of the last 30 years, a hospital series of 5443 patients undergoing cataract extraction between 1956 and 1987 is reviewed. All cases attended the same University Eye Clinic of Milan and most were resident in the same geographical area. Cases with macular or optic nerve diseases were excluded. Results show that mean age at cataract surgery progressively increased from 67.5 to 71.5 years (slope = +0.096 years of age per year, p = 0.0001) as did visual acuity at surgery (patients with visual acuity levels greater than or equal to 1/10 at time of cataract surgery rose from 3.2% to 47.9%). These results can be interpreted in terms of a change in age composition of the Italian population, improved access to health services for the elderly, and an improvement in surgical and rehabilitation techniques.

Prehospital cardiac arrest--a critical analysis of factors affecting survival.

During a 10-year period, 5631 cardiac arrests were treated in our paramedic system. In all, 4216 resuscitations were attempted, of which 533 (12.6%) resulted in saves, defined as hospital discharges. Patients presenting with an initial rhythm of coarse ventricular fibrillation or ventricular tachycardia were found to have significantly increased save rates in comparison to those presenting with an initial arrest rhythm of asystole/fine ventricular fibrillation or electromechanical dissociation (P less than or equal to 0.01). When controlling for witnessed arrest, 303 of 1905 (15.9%) of all witnessed arrests were saves vs. 230 of 2311 (10%) of unwitnessed arrests (P less than or equal to 0.01). Witnessed bystander/first responder external cardiac compression- cardiopulmonary resuscitation (ECC-CPR) was found not to influence save rate. One hundred eighty-one of 1248 bystander/first responder witnessed arrests (14.5%) who had external ECC-CPR initiated before paramedic advanced life support arrival were saves, compared with 38 of 252 (15.1%) who had no ECC-CPR initiated until paramedic arrival; this was not statistically significant. Advanced life support response times in saved patients with witnessed cardiac arrests were analyzed. Ninety-five percent of all saves had a response time of less than 10 min. We conclude that, when evaluating the effectiveness of CPR, the variables of witnessing of arrest, presenting arrest rhythm, and respective response times must be controlled or analyzed.

The effect of bystander CPR on neurologic outcome in survivors of prehospital cardiac arrests.

The efficacy of CPR has been questioned. A major criticism is that neurologic outcomes have not been adequately studied. For a 26-month period, 138 patients from six major receiving hospitals were discharged alive following prehospital cardiac arrests. For 65/138 (47.1%) patients, either the patient or a direct family member was contacted for information concerning neurologic outcome. For 63/138 (45.7%) patients, contact with patient or family was unsuccessful, consequently neurologic outcome at time of discharge was obtained from the medical record. For 10/138 (7.2%) patients, no data on neurologic outcome was obtainable. Neurologic outcome was rated by a 5-point Cerebral Performance Categories Scale (CPC); (1) Minimal Disability; (2) Moderate; (3) Severe; (4) Vegetative; and (5) Brain Dead. The bystander/first responder CPR group had 55.1% CPC-1; 24.4% CPC-2; 16.7% CPC-3; and 3.8% CPC-4 outcomes. The bystander/first responder NO CPR group had 58.0% CPC-1; 18.0% CPC-2; 16.0% CPC-3; and 8.0% CPC-4 outcomes. There was no significant difference at any CPC level (P not significant). Furthermore, there was no statistical difference between either group when compared for age, response time, resuscitation time, witnessing of arrest or distribution of presenting rhythms. In conclusion, no significant effect in neurologic outcome among saved cardiac arrest victims was found between bystander/first responder CPR and bystander/first responder NO CPR groups in the paramedic program studied.

Prehospital external cardiac pacing: a prospective, controlled clinical trial.

This prehospital prospective, controlled study was conducted to determine if prehospital cardiac pacing affects survival. The study involved 239 patients, 226 pulseless, nonbreathing patients (rhythms of asystole and electromechanical dissociation with heart rates less than 70) and 13 patients with hemodynamically significant bradycardia (heart rate less than 60; blood pressure less than 90 mm Hg; not responding to atropine). Patients were assigned to treatment or control groups on an every-other-day basis. One hundred three patients were treated with an external cardiac pacing device; 22 (21.4%) were resuscitated (arrival at admitting hospital with pulse and blood pressure) and seven (6.8%) were saved (survival to hospital discharge). One hundred thirty-six patients were not paced and served as controls; 28 (20.6%) were resuscitated (P = .90) and six (4.4%) were saved (P = .71). Analysis of pacing times showed increased resuscitation in patients paced early. All surviving paced patients were paced in 17 minutes or less. Analysis of rhythm subgroups showed no significant difference in the resuscitation or survival rates of paced and control groups for primary asystole, primary electromechanical dissociation, and secondary asystole and electromechanical dissociation occurring after countershock treatment of ventricular fibrillation when compared respectively. However, among patients with hypotensive bradycardia, six of six paced patients were resuscitated and five were saved, while only two of seven controls were resuscitated (P = .01) and one was saved (P = .01). Interpretation of the bradycardic patient data is limited by inequalities noted between control and treatment groups with regard to the administration of isoproterenol.(ABSTRACT TRUNCATED AT 250 WORDS)