Calázio e características demográficas dos portadores em uma amostra populacional Chalazion and demographic characteristics of patients in a population sample

The analysis of patients with chalazion was based on datafrom a cross-section, observational study made with a randomizedpopulation sample conducted between March 2004 and June2005. The study was conducted in nine cities of the Midwestregion in the state of Sao Paulo, for which the reference center isthe city of Botucatu. The research protocol was reviewedand approved by the Research Ethics Committee of the MedicineCollege of Botucatu - UNESP.Participants were sorted taking into account the place ofresidence according to the IBGE census tract (Census, 2000).The sample size of 8,010 individuals was stablished, of which 7,654people were examined. The sample size was based on the totalnumber of inhabitants of the study area and on the prevalenceof blindness and low vision in the population studied. The subjectswere invited to participate and an appointment was scheduled.The study population was approached by a MobileOphthalmic Unit, registering the identification data, clinicalhistory, and ocular and systemic background of the participants.Then an eye examination was performed with the assessment ofvisual acuity (VA) by means of the Snellen chart for the illiterateplaced 5 meters away and with good lighting conditions, withand without optical correction. The external ocular exam wasperformed with a hand-held flashlight. The static and dynamicrefractometry values were recorded using an auto-refractor(Topcon KR-7000, Japan) and a phoropter (Topcon VT10, Japan).The biomicroscopy assessment was performed using a slit lamp(Shin-Nippon, Japan), and the indirect fundoscopy was performedusing 90D Volk lens (Mentor, USA).In individuals aged below 40 years, cycloplegia wasobtained by instilling a droplet of cyclopentolate eyedrops(Cicloplegico, Allergan, Sao Paulo-Brazil), with examination after30 minutes.Individuals with a spherical component between -0.50 and+0.50 were considered emmetropic, hyperopic with a degreegreater than +0.50, and astigmatic with a degree lower than -0.50.All data obtained was categorized and transferred to anExcel table, being statistically treated for the frequency analysisof occurrence of the phenomena observed.