Sains Malaysiana 39(4)(2010): 685–688

Soft Contact Lens Parameter Changes After using the Lens2¨ Automated Lens Cleaner Machine

(Perubahan Parameter Kanta Sentuh Lembut Selepas Menggunakan Mesin Pencuci Automatik Lens2¨)

Haliza Abdul Mutalib* & Kang Chye Lee

Department of Optometry, Faculty of Allied Health Sciences

Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia

Received: 11 June 2009 / Accepted: 7 January 2010

ABSTRACT

Disinfection of contact lens is an important procedure strongly emphasized by eye care practitioners. There are several types of disinfecting methods. Some methods have been proven to induce parameter changes on soft lenses. These parameter changes are likely to affect the efficacy of contact lens fitting and patients comfort. A self-controlled trial was carried out on a series of disposable soft contact lenses of different material to evaluate parameter changes after cleaning with Lens2¨ (Automated Lens Cleaner Machine). This will be compared to the lens cleaned conventionally (digital rubbing). Fifty four pieces of soft contact lenses were divided into 2 groups; cleaned conventionally and with Lens2¨. Three types of soft contact lenses of different materials were used; Soflens®38, Focus® Monthly and O2 Optix. Each contact lens was cleaned for 30 times to mimic the period of 30 days wear. After the thorough cleaning process, the back optic zone radius (BOZR), back vertex power (BVP), central thickness(ct) and total diameter (TD) were measured. The parameters were statistically analysed to evaluate the changes. There were significant changes in the TD and BVP of Soflens®38 and O2 Optix with both methods. The Focus® Monthly contact lens only showed significant BOZR changes with both methods. However, these parameter changes were not clinically significant because the changes were still in the tolerance range set by ISO (International Organization of Standardization). Both cleaning methods proved to maintain lens parameter within its acceptable range.

Keywords: Automated Lens Cleaner Machine; Lens2¨; Soft Contact Lens 

ABSTRAK

Disinfeksi kanta sentuh adalah satu prosedur yang sangat penting yang kerapkali ditekankan oleh pengamal penjagaan mata. Terdapat beberapa kaedah disinfeksi. Sesetengah kaedah telah dibuktikan boleh menyebabkan perubahan parameter kanta. Kesemua perubahan parameter akan memberi kesan terhadap pemasangan kanta sentuh dan keselesaan pemakai. Satu percubaan swakawal telah dijalankan ke atas satu siri kanta sentuh lembut pakaibuang pelbagai bahan untuk evaluasi perubahan parameter selepas pencucian dengan menggunakan Lens2¨ (Mesin Pembersih Kanta Otomatik). Ini akan dibandingkan dengan kanta yang dicuci secara konvensional (digosok secara digital). Sebanyak lima puluh empat keping kanta sentuh lembut telah dibahagikan kepada dua kumpulan; dicuci secara konvensional dan dengan Lens2¨.Tiga jenis kanta sentuh berlainan bahan digunakan; Soflens®38 , Focus® Monthly dan O2 Optix. Setiap kanta sentuh dicuci selama 30 kali untuk meniru pemakaian selama 30 hari. Selepas proses pencucian yang rapi , zon optik radius belakang (BOZR), kuasa verteks belakang (BVP), ketebalan tengah(ct) dan diameter total (TD) diukur semula. Parameter yang diukur telah dianalisis secara statistik untuk menilai perubahannya. Perubahan pada diameter total dan kuasa vertek belakang bagi Soflens®38 and O2 Optix didapati signifikan untuk kedua-dua prosedur. Kanta sentuh Focus® Monthly hanya menunjukkan perubahan signifikan pada BOZR bagi kedua-dua kaedah. Walau bagaimanapun, kesemua parameter ini tidak signifikan secara klinikalnya kerana perubahan parameter yang berlaku adalah dalam julat yang dibenarkan oleh ISO (International Organization of Standardization). Kesimpulannya, kedua-dua kaedah pencucian telah membuktikan parameter kanta dapat dikekalkan dalam julat yang diterima.

Kata kunci: Kanta sentuh lembut; Lens2®; Mesin Pembersih Kanta Otomatik

REFERENCES

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*Corresponding author; email: haliza@medic.ukm.my