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Biomedical subjects

B Piccoli

Publications and source records attributed to B Piccoli.

At least 19 recordsLinked to original sources
PubMed2005

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.

Air Pollutants, Occupational↗
PubMed2004

Photometry in the workplace: the rationale for a new method.

OBJECTIVES: The assessment of lighting conditions in workplaces has traditionally focused on the measurement of illuminance. The rationale for a new method for the detailed evaluation of natural and artificial light in 'near work' situations, involving the assessment of luminance, is described. METHODS: The procedure comprises four successive phases: (1) identify object/images observed during work tasks; (2) outline the area of the operator's visual field where gaze is predominantly directed; (3) measure luminances in the visual field, pin-pointing all sources of primary and secondary luminance, and constructing iso-luminance maps; and (4) compare luminance ratios. RESULTS: The procedure was illustrated using the common example of near work in an office environment. Illuminance was found to be inadequate to evaluate the effects of natural and artificial environmental light in the workplace. This is due to the fact that the luxmeter is designed to integrate the light detected over a large angle, whereas in near work the operator's retina is mainly stimulated by light originating from objects/images placed in the occupational visual field. CONCLUSIONS: A detailed measurement of luminance within the occupational visual field is consistent with ocular anatomy and physiology, and can be used as part of a risk assessment for visual disturbances and to rationalize lighting at workstations.

Asthenopia↗
PubMed2001

Microbiological pollution and ocular infection in CAD operators: an on-site investigation.

A large number of workers are currently employed in tasks involving the use of computer based equipment. Much research has been carried out both on prevalence and incidence of ocular and visual disorders as well as on occupational asthenopia. Less attention has been given to investigating the possibility of a microbiological pollution of Video Display Unit (VDU) workstations and to the consequent possible development of work-related ocular infections. The authors investigated the presence of bacteria and fungi on Computer Assisted Design (CAD) workstations and in the conjunctival sac of the operators.

Air Microbiology↗
PubMed2001

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.

Air Pollution, Indoor↗
PubMed2000

Ergonomic guidelines for using notebook personal computers. Technical Committee on Human-Computer Interaction, International Ergonomics Association.

In the 1980's, the visual display terminal (VDT) was introduced in workplaces of many countries. Soon thereafter, an upsurge in reported cases of related health problems, such as musculoskeletal disorders and eyestrain, was seen. Recently, the flat panel display or notebook personal computer (PC) became the most remarkable feature in modern workplaces with VDTs and even in homes. A proactive approach must be taken to avert foreseeable ergonomic and occupational health problems from the use of this new technology. Because of its distinct physical and optical characteristics, the ergonomic requirements for notebook PCs in terms of machine layout, workstation design, lighting conditions, among others, should be different from the CRT-based computers. The Japan Ergonomics Society (JES) technical committee came up with a set of guidelines for notebook PC use following exploratory discussions that dwelt on its ergonomic aspects. To keep in stride with this development, the Technical Committee on Human-Computer Interaction under the auspices of the International Ergonomics Association worked towards the international issuance of the guidelines. This paper unveils the result of this collaborative effort.

Equipment Design↗
PubMed1996

Viewing distance variation and related ophthalmological changes in office activities with and without VDUs.

This experimental study was conducted on 14 volunteer female clerks to measure viewing distance variation and related ophthalmological changes in office activities with (session 1) and without (session 2) VDU. A video camera connected to an electronic elaborator was used to determine eye-screen distance of the VDU operators during the task. Before and after each of the two work sessions far refraction, far phorias, near point of accommodation (APP), and fusional convergence were measured. Blinking rate of each subject was measured by a transducer only during the "VDU session'. The objective measurements of the eye-screen distance, whose range was between 48.42 and 65.33 cm, allowed a precise quantification of the occupational visual load during session 1. The accommodation was about 1.5-2D on average and the fusional convergence 10-13 delta on average. The symptomatology shows a number of disturbances in session 1 (71.4%) clearly higher than in session 2 (35.7%). The study of refraction before and after the task has shown a slight excess of accommodation compared to the theoretical value in both sessions, more marked in session 1. The APP shows no statistical significative variation. A tendency to exophoria was registered at the beginning and at the end of the trial and the fusional convergence clearly decreased, especially in the first session.

Accommodation, Ocular↗
PubMed1990

Change in visual function and viewing distance during work with VDTs.

Seven female volunteer bank clerks aged between 24 and 32 yr were selected for a laboratory trial after a preliminary ocular examination which showed them to be emmetropic or slightly myopic (less than or equal to 1D) and to have normal ocular motility or only minor deficiencies. Near and far point refraction and phorias and near point fusional vergences were measured before and immediately after a 6 h workday at a PC workstation. Eye screen distance (viewing distance) was monitored. Near and far distance refraction showed an increase and a decrease of accommodation in 13 out of 14 eyes respectively. Fusional convergence decreased in six out of seven cases: a smaller decrease in divergence was recorded in all subjects. These changes were statistically significant. Viewing distance, though showing some interindividual differences, increased considerably during the last 2 h of the trial, without reaching statistical significance.

Adult↗
PubMed1989

[Asthenopia and objective ophthalmological findings in a population of 2058 VDT operators in Lombardy].

A large population of 2058 VDT operators from all compartments in Lombardia of a large national company was studied. An "ergophthalmological" questionnaire was administered to all subjects, followed by an ophthalmological-orthoptic examination. Ametropias showed a prevalence of 51.9%; the most common refractive defect was myopia followed by astigmatism and hyperopia. Heterophorias with bad or mediocre compensation had a prevalence of 4.1 and 11% respectively. The study of symptoms showed a frequency of 23.5% of intense asthenopic complaints and 21.1% of less severe and less frequent symptomatology. Asthenopia was significantly correlated (chi square) with sex, VDT exposure, refraction, presbyopia, and decompensated heterophorias.

Adult↗
PubMedDate not supplied

[Occupational ophthalmology and ergoophthalmology: a developing field].

In 1979 it was decided to activate, within the Institute of Occupational Health of the Milan "Università degli Studi", a new Unit of Ergophthalmology. This decision was taken owing to the progressive diffusion of "optical instruments", particularly computer-based equipment, in the world of work and to the relevance that this topic assumed among Italian occupational physicians. Since its beginning, one of the main characteristics of the Ergophthalmology Unit was an interdisciplinary approach, where occupational physicians, ophthalmologists, occupational hygienists and lighting engineers were collaborating on a daily basis. Research activities, which developed over many years and in several phases, were concerned with four main topics: 1. analysis and quantification of "near work load"; initially the investigations were mainly aimed at the evaluation of the observation distance in different tasks, followed by the development of a method which, by means of specifically designed electronic equipment, allows quantification of the accommodation and convergence required by the task; 2. development of a new method aimed at evaluating, by a photometric procedure, the luminance ratios in the "occupational visual field"; this research was carried out, both in the laboratory and during on-site investigations, in collaboration with the Dept. of Electrotechnics of Milan Polytechnic; 3. studies on the relationships between indoor microbial pollution and Computer Assisted Design work, considering that ocular conjunctiva and cornea, due to their external position, can be easily inoculated by micro-organisms present on periocular tissue and hands; this research showed that bacteria and fungi pathogenic for the eye (Staphylococcus aureus, Candida sp., Aspergillus sp.) are present on desk, keyboard and mouse, as well as in the conjunctival sac of the exposed operators; 4. studies on "blue light" and its effects on the Pigmented Retinal Epithelium (PRE) in workers exposed to halide lamps, like electricians, installers, maintenance staff, polymerization operators, etc.; the laboratory and on-site investigation that was carried out in cooperation with the Health Physics Dept. of the Milan ICP Hospital, showed that long-term exposure to low levels of irradiation could constitute an eye risk for these working populations.

Computer Terminals↗
PubMedDate not supplied

[Lighting condition analysis at work].

Following a wide review of the national and international technical standards which make up the principal reference points when designing illumination systems for work areas, the most commonly used methods of photometric analysis are examined from both a medical and technical point of view. It can be observed that photometric analysis of the work place, which currently is almost exclusively based on the measurements of illuminance, does not appear to adequately reach the targets set by Occupational Health and Occupational Hygiene, for reasons pertaining to the anatomy and physiopathology of the visual function. Moreover, the procedures applied to evaluate the workers' subjectivity and/or symptomatology, that both in research and during on-site investigations makes use predominantly of self-administered questionnaires, shows some shortcomings in terms of reliability and validity. In conclusion, it is proposed, especially in studies regarding office environments (i) to carry out photometric analysis where primary and secondary luminance is always measured and, if light-linked subjectivity is required (ii) to make available valid and precise questionnaires whose administration be followed by a multivariate data analysis.

Asthenopia↗
PubMedDate not supplied

[Non-visual effects of light mediated via the optical route: review of the literature and implications for occupational medicine].

Artificial light which now plays an essential role in industrialized society differs from natural light both in intensity which is usually lower, and in spectrum, which is usually smaller. It is now a well-known fact that the human body is able to use luminous stimulation for aims other than sight; the pineal gland, though no longer directly sensitive to light as in lower animals, is nevertheless the fulcrum of a complex neuro-endocrine system which makes an interaction between light and the human body possible by means of the production of a number of substances of which melatonin is the most widely investigated. Melatonin is secreted at a circadian rhythm characterized by high nocturnal seric levels and low diurnal levels. This secretion appears to be correlated not only with the intensity of the light but also with its spectrum and time exposure. Even though the function of melatonin is still not fully understood, it seems possible to assign a mainly modulatory role to the pineal gland and melatonin. On the basis of studies performed on the pituitary-gonadal and/or hypothalamic axis and the reproductive system in animals, melatonin would appear to affect some endocrine functions (i.e., puberty) in man, too. Changes in melatonin secretion have been found in psychiatric illness, especially in cyclical affective disorders. Melatonin seems to be involved in stress-associated mechanisms, probably with an agonistic role, and also in carcinogenesis, where it seems to play a role in the growth of several tumors. Melatonin also affects both tumoral and cellular immune responses. Lastly, melatonin may be able to reduce the symptoms of the Jet Lag Syndrome. The consequences that prolonged and marked reduction in daylight exposure for occupational reasons could have on operators, especially young people, therefore constitute an interesting subject for occupational health; environmental photometry at the work-place, if adequately performed, could make a useful contribution to the development of this field of research.

Adolescent↗
PubMedDate not supplied

[Dermatitis in VDT operators: a review of the literature].

The paper reports studies on the relationship between work with VDT's and dermatitis in the operators. From the first observation in 1979, numerous studies have been carried out to try and explain the reason why some forms of dermatitis like rosacea, eczema seborrhoeic and erythematitis appeared more frequently in VDT operators compared to the general population. The various authors at present consider low indoor air humidity associated with a strong electrostatic field to be essential factors in the occurrence of dermatitis. Laboratory experiments have shown that the presence of a strong electrostatic field does not seem to be important in itself. Similarly, it is agreed that X, UV-A or UV-B radiations do not play any causative role in dermatitis. Further investigations are required to assess the influence of indoor climatic factors and the presence of irritant substances in the air of the working environment.

Computer Terminals↗
PubMedDate not supplied

[Mean-term variations of visual function of video display terminal operators: observations on 70 cases].

The aim of the study was to evaluate medium-term variations of visual functions in VDT operators and their possible relationship to VDT exposure. The clinical records of 70 VDT operators attending our outpatient service for periodical ergophthalmological evaluation were reviewed in order to evaluate the variation of some visual parameters after a two-years follow-up. These included refraction, phorias, fusional convergence and divergence, stereopsis. The group did not include subjects affected by hyperopia, large ametropias, or binocular vision disturbances and was divided into two subgroups: low exposure group (n = 20; < 4 hours/day) and high exposure group (n = 50; exposure > 4 hours/day). Asthenopia was frequent in both groups. Variation of refraction and binocular vision parameters were absent or rather limited in both exposure groups. This seems to indicate that in subjects without significant ophthalmological problems the risk of permanent functional damage is very low at medium-term.

Adult↗