Validitas pemeriksaan tonometer Schiotz oleh paramedis terlatih untuk skrining glaukma

LUTFI, M. Faisal, Dr. Hartono, SpM(K)

2007 | Tesis | PPDS I Ilmu Penyakit Mata

Title: The validity of Schiotz tonometry for glaucoma screening by trained paramedics. Purpose: To determine the validity of Schiotz tonometry for glaucoma screening by trained paramedics. Hypothesis: The sensitivity and specificity of intraocular pressure measurement using Schiotz tonometry for glaucoma screening by trained paramedics were 50% and 90%, respectively. Significance of the study: To determine whether measuring intraocular pressure by using Schiotz tonometry could be used for glaucoma screening. Design: Diagnostic test. An observational-prospective study. A blinded comparison of the glaucoma screening results between the trained paramedics and ophthalmic resident. Setting: Imogiri I Primary Health Centre, Bantul, Jogjakarta, Indonesia. Participants and methods: Two paramedics whom had been chosen were trained to use the Schiotz tonometry. Both paramedics examined the intraocular pressure of the patients that were enrolled in the study, whom have been diagnosed as glaucoma by ophthalmologic resident based on optic nerve head cup/disc ratio examination and Schiotz tonometry; then, the results yielded by paramedics and ophthalmologic resident were compared. The inclusion criteria of the study were as follows: 35 years old of age or older, both male or female, quite eyes, clearly visualized optic nerve head and its margin, no secondary glaucoma causes, and willing to participate in the study. Main Outcome Measures: The sensitivity, specificity, predictive value, and the likelihood ratio. Result: The number of subjects that were enrolled in the study were 520 persons, i.e. 1040 eyes. Two hundreds and twenty two were males, the other 298 were females. The age ranged from 35 to 83 years old. Using cut off point of 20 mmHg, it were found that the sensitivity and specificity level of Schiotz tonometry were 57.57% and 88.09%, respectively; while the predictive value for positive and negative examination results were 24.67% and 96.83%, respectively. The likelihood ratio for positive result was 4.83 and for the negative result was 0.48. Using cut off point of 21 mmHg, the sensitivity reduced to 43.98%, while the specificity increased to 89.01 %; the same result, i.e. decreased sensitivity and increased specificity, were found when 23 mmHg, 25 mmHg and 28 mmHg were set as cut off points. The ophthalmologic resident found that determination of cup/disc ratio and measurement of intraocular pressure using tonometer Schiotz had sensitivity level of 98.48% and specificity level of 96.30% when 20 mmHg was used as cut off point. Conclusion: Although the study result was not found to be ideal, i.e. Schiotz tonometry did not have a high sensitivity and specificity, the results still met the original purpose of the study which was to find screening method with high sensitivity and specificity when 20 mmHg was used as cut off point. More glaucoma cases were missed when 21 mmHg was set as cut off point due to lower sensitivity despite the advantage of increased specificity.

Kata Kunci : Skrining Glaukoma,Tonometer Schiotz, Glaucoma-screening-Schiotz tonometry-sensitivity-specificity