On-screen work and visual fatigue and its course after ophthalmologic management

INTRODUCTION: The number of staff subjected to significant amounts of on-screen work with visual complaints is currently increasing. OBJECTIVE: This epidemiological study aimed to observe the influence of changes in working conditions and an ophthalmological treatment on vision and eye complaints due to on-screen work. MATERIALS AND METHODS: This comparative study included a transversal initial study on the visual symptoms and function as well as a longitudinal follow-up of the efficacy of the recommendations given by the company medical officer. The studied subjects were be exposed to screen irradiation for at least 4 hours a day during the study. The control group was selected according to the age, sex, and education level of the investigated group. RESULTS: We examined 814 subjects under investigation and 325 control subjects. The subjective signs of visual fatigue with on-screen work (burning or stinging eyes, diplopia or blurred vision after work, tearing, globe heaviness and fatigue, and headaches, the latter particularly in female subjects) were significantly more frequent in the exposed group than in the control group. A statistically significant correlation was found with the following factors: poor working conditions, frequent keyboard data entry, far vision optic correction, far vision significantly more often corrected to less than 10/10 at least in one eye, and, finally, near vision exophoria more than 7 diopters. We re-examined 465 exposed and 139 control subjects 1 and 2 years after consultation with the company medical officer. Following the recommendations proved to be effective in 50.5% of the employees. Improving vision by changing the optical correction showed the strongest statistical relation with the decrease in visual fatigue complaints. Organizational and material improvements also led to positive effects on functional discomfort. DISCUSSION: The far vision of those exposed to screen irradiation was significantly worse than in those who were not exposed. The people from the exposed group had vision correction significantly more often. The probable relation between progressive myopia and on-screen work is not excluded, but further investigation is needed. The proposed measures were effective for preventing visual fatigue. However, 49.5% of the study group had persistent visual symptoms, probably because of not following the recommendations, not having an ergonomic correction, or because modifications of blinking, tear film, and the ocular surface were ot taken into account. CONCLUSION: The coordination between the occupational medicine and ophthalmology departments during this study has significantly reduced visual fatigue. Nevertheless, there is still a considerable number of people from the exposed group with persistent symptoms.     

Porencephaly as a cause of ophthalmologic symptoms

Two cases of hypoplasia of the optic nerve associated with porencephaly and one case of porencephaly without ophthalmologic signs are described. The clinicopathological correlation of the double-ring sign is presented and the possible mechanism of optic nerve hypoplasia being a secondary degeneration is discussed.     

Lyell's syndrome and its ophthalmologic manifestations in Cameroon

BACKGROUND: To study basic epidemiological datas and ocular involvment during toxic epidermal necrolysis (T.E.N.) in Cameroonian patients. METHODS: Ten consecutive patients in the Central Hospital of Yaounde were included during a 4 years period. Anamnesis, clinical features, dermatological, ophthalmological and pathological examinations were done. Minimal follow up of 3 months. RESULTS: Mean age: 20.1 +/- 11.4 yrs (SD); culprit drugs: sulfadoxin (5/10), sulfamethoxazol (3/10); phenytoin (1/10). Mean of skin detachment: 41 +/- 17%. 2 patients died with sulfadoxin as culprit drug. Early ocular findings: conjunctivitis (all patients), symblepharon (1/8), ankyloblepharon (3 patients over 8 with sulfadoxin as culprit drug). All cases with ankyloblepharon (3) evoluated toward formation of a fibrovascular precorneal membrane with blindness. Two of the patients received a kerothoprosthesis on one eye. The 3 patients had a severe dry eye syndrome. CONCLUSION: TEN appears to be uncommon in Cameroon. Use of sulfonamides for treatment and prevention of malaria and AID'S opportunistic infections may increase the incidence of disease in tropical african areas. Ophthalmologists should be aware of early management of ocular manifestations in Lyell syndrome to avoid severe sequelae. That sequelae may be due to usual intensive healing in African patients. Severe corneal damages can be corrected only by keratoprosthesis.     

Fronto-naso-ethmoido-sphenoido-maxillo-orbital mucocele with ophthalmologic presentation]

PURPOSE: We present a case of a large mucocele pressing the orbit forward and compared our findings with those reported by others. CASE REPORT: A 23-year-old woman was examined for an inflammatory tumor of the internal canthus. She had a 6/10 vision loss of the left eye, diplopia, and non-axial exophthalmos. CT scan and magnetic resonance imaging evidenced a huge sinus mucocele behind the orbit. Surgery using the paralateronasal approach was performed. Pathology confirmed the diagnosis of mucocele. DISCUSSION: Ophthalmic complications of mucoceles result from tumor growth leading to compressive optic neuropathy or even compression of the chiasma. A sinus mucocele should be suspected upon indirect clinical signs and lead to neuroradiological explorations. Magnetic resonance imaging reveals iso- or high signals on T1-weighted sequences and high signal on T2-weighted sequences. MRI evidences intracranial or orbital extension. CT scan reveal the degree of bone erosion. Prognosis is favorable after surgical treatment. It is important to correctly diagnose mucocele on the basis of clinical and neuroradiological findings in order to propose early surgery and prevent permanent visual loss by compressive optic neuropathy.     

Comparative ophthalmologic studies on children and adults with craniopharyngiomas

The subjects of the study are 74 patients with craniopharyngiomas treated at the Clinic of Neurosurgery, Bulgarian Medical Academy, within the period 1960-1989. Fifty of the patients are children and 24 adults. The diagnosis of all patients is made on the base of clinical, X-ray and histological studies. The ophthalmologic state was studied in all patients, prior to operation, via routine methods. Reduced visual acuity was established in 69.6% of the children and 81.8% of the adults. The presence of congestive optic papilla was diagnosed in 22% of the children and 12.5% of the adults. Optic atrophy was established in 62.5% of the adults and 52% of the children. Various defects in the visual field were established in 67.7% of the children and 81.8% of the adults with the predomination of bitemporal defects. The use of highly informative conventional and modern X-ray methods is recommended in all patients suspected of compression of the visual pathways.     

眼前节相干光断层扫描仪在眼科的应用

眼前节相干光断层扫描仪(VisanteOCT)是基于眼组织结构的不同光学散射性,采用干涉测量法进行二维显像和定量分析的新技术。与目前临床应用的其他眼前节检测手段如超声生物纤维镜(UBM)、超声角膜测厚仪、多功能眼前节分析诊断系统(OrbscanⅡ),光学生物测量仪(IOLmaster)、房角镜等相比,OCT具有非接触性、高分辨率、可重复性高、获取图像快等特点。目前VisanteOCT可应用于角膜、前房角、晶状体等眼前节结构的生物测量和眼病研究,并可进行术前、术后动态观察和实时显像。     

内皮素-1与眼科主要致盲性疾病的关系

内皮素-1(Endothelin-1,ET-1)是一种含有21个氨基酸的血管活性肽,它是目前被认为的最强的缩血管物质。它不仅具有强大的收缩血管的作用,还可以促进炎症的产生。它除了对心血管、泌尿、呼吸、消化、神经、生殖、内分泌等系统中起作用外,对眼科的各种致盲性疾病起着十分重要的作用,如内皮素-1在眼部中主要分布在脉络膜中,它对白内障的发展、青光眼眼压的升高及视神经的损害有一定联系。内皮素-1对糖尿病性视网膜病变中微血管稳态的维持及病情的诊断有一定作用;在非动脉炎性前部缺血性视神经病变中,它的浓度的高低与病变程度相吻合,对病情的判断和预后评估均有一定的临床意义。随着内皮素-1在这些疾病中的作用机制研究的不断深入,未来眼科相关疾病的预防和治疗将大有裨益。