Sains Malaysiana 42(6)(2013): 753–758

Definisi Miopia Menggunakan Retinoskopi Tanpa Sikoplegia dalam Kalangan Pelajar Melayu

(Definition of Myopia Using Retinoscopy Without Cycloplegia in Malay Schoolchildren)

Saadah Mohamed Akhir*, Norhani Mohidin, Norliza Md Fadzil & Rokiah Omar

Program Optometri & Sains Penglihatan, Pusat Pengajian Sains Jagaan Kesihatan

Fakulti Sains Kesihatan, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz

50300 Kuala Lumpur, Malaysia

Diserahkan: 3 September 2012/Diterima: 2 Oktober 2012

ABSTRAK

Miopia pada kebiasaannya didefinisi sebagai sfera setara ≥ -0.50 D dalam banyak kajian yang dilaporkan. Namun demikian tidak banyak laporan berkaitan kesensitifan dan kekhususan definisi miopia yang dipilih apabila penyelidik melaporkan prevalen dan taburan miopia dalam populasi yang dikaji. Objektif kajian ini adalah membezakan kesensitifan dan kekhususan setiap definisi miopia yang dipilih, iaitu -0.50 D, -0.75 D dan -1.00 D dan untuk mengenal pasti kebolehan definisi tersebut meramalkan ralat refraksi miopia pada akuiti penglihatan kurang daripada log MAR 0.3 (6/12) dalam kalangan pelajar Melayu. Seramai 866 orang pelajar Melayu berumur antara 7-10 tahun mengambil bahagian dalam penyelidikan ini. Akuiti penglihatan diukur menggunakan carta log MAR dan ralat refraksi diukur menggunakan retinoskopi tanpa sikloplegia. Keputusan kami menunjukkan kesensitifan dan kekhususan definisi miopia yang dipilih iaitu ≥ -0.50 D adalah 54.5% dan 97.8%, untuk definisi miopia ≥ - 0.75 D adalah 71.1% and 97.5% dan untuk definisi miopia ≥ -1.00 D adalah 83.3% dan 97.2%. Luas lengkok ROC untuk setiap definisi miopia -0.50 D, -0.75 D dan -1.00 D ialah 0.676, 0.839 and 0.957. Kesimpulannya, kajian ini menunjukkan definisi optimum miopia untuk pelajar sekolah Melayu berumur antara 7-10 tahun ialah ≥ -1.00 D, dengan menggunakan kaedah retinoskopi tanpa sikloplegia. Definisi ini boleh mengenal pasti 95.7% pelajar mempunyai akuiti penglihatan kurang daripada log MAR 0.3 dan ia mempunyai gabungan kesensitifan (83.9%) dan kekhususan (95.7%) terbaik.

Kata kunci: Kanak-kanak sekolah; miopia; ROC; kesensitifan; kekhususan;  tanpa sikloplegia

ABSTRACT

Myopia is usually defined as equivalent sphere ≥ -0.50D in most reported studies. However, the literature is scanty on the sensitivity and specificity of the defined myopia when researchers report the prevalence or distribution of myopia in the population under study. The objective of this study was to differentiate the sensitivity and specificity of each myopia definition of -0.50 D, -0.75 D and -1.00 D and to establish each myopia definition’s capability to predict visual acuity less than log MAR 0.3 (6/12) in Malay schoolchildren. Eight hundred sixty six schoolchildren aged 7 – 10 years were involved in this study. Visual acuity was measured using log MAR chart and refractive error was determined using retinoscopy without cycloplegia. Our results showed that the sensitivity and specificity for myopia defined as ≥ -0.50 D were 54.5% and 97.8%, respectively, for myopia defined as ≥ - 0.75 D were 71.1% and 97.5%, respectively, and for myopia defined as ≥ -1.00 D were 83.3% and 97.2%, respectively. Areas under ROC curve for each myopia definition of -0.50 D, -0.75 D and -1.00 D were 0.676, 0.839 and 0.957, respectively. In conclusion, our results showed the optimal myopia definition for Malay schoolchildren aged 7-10 years was ≥ -1.00 D using retinoscopy without cycloplegia. This myopia definition was able to establish 95.7% schoolchildren with visual acuity less than log MAR 0.3 and it has good combination of sensitivity (83.9%) and specificity (95.7%).

Keywords: Myopia; non-cycloplegic; ROC; schoolchildren; sensitivity; specificity

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*Pengarang untuk surat-menyurat; email: sma@medic.ukm.my