Design and implementation of a portable device for visual field testing

Abstract

Inspired by the Humphrey Field Analyzer (HFA) device used in the diagnosis and monitoring of diseases such as glaucoma that cause vision loss, this study developed a low-cost, portable device application that is integrated with existing devices and has a design that facilitates patient use. The system design consists of mechanical, hardware, and software components. The mechanical design includes a visual stimulus box integrated with a special chin rest to ensure user ergonomics and reliable results. The hardware component features an LED-based visual stimulus circuit designed in a 24/2 pattern and controlled by an Arduino Mega microcontroller. The functionality of the hardware has been verified using Proteus simulation software. On the software side, a user interface has been developed using MATLAB Appdesigner, which enables two-way communication with the Arduino Mega microcontroller via a serial port. The developed visual field-testing system is a low-cost, easy-to-install, portable, and reliable system that does not require specialized technical personnel. Compared to commercial devices, the design eliminates motor noise associated with stimulus projection in HFA devices, making it quieter and less distracting for users. This study offers a cost-effective, user-friendly, and portable alternative to traditional visual field-testing devices for potential clinical diagnosis and patient education applications.

Keywords

• Visual field test
• Glaucoma Diagnosis
• Low-Cost Medical Device
• Humphrey Field Analyzer

Görme alanı testi için taşınabilir bir cihaz tasarımı ve uygulaması

Öz

Görme alanı kaybına neden olan glokom gibi hastalıkların teşhisi ve takibinde kullanılan Humphrey Alan Analizörü’nden (HFA) esinlenilen makale çalışmasında mevcut cihazlara uyum sağlayan ve hasta kullanımını kolaylaştıran tasarım ile düşük maliyetli ve taşınabilir bir cihaz uygulaması geliştirilmiştir. Sistem tasarımı mekanik, donanım ve yazılım bileşenlerinden oluşmaktadır. Mekanik tasarım, kullanıcı ergonomisini ve güvenilir sonuçları sağlamak için özel bir çene desteği ile entegre edilmiş bir görsel uyaran kutusu içerir. Donanım bileşeni, bir Arduino Mega mikrodenetleyici tarafından kontrol edilen 24/2 deseninde tasarlanmış LED tabanlı bir görsel uyaran devresine sahiptir. Donanımın işlevselliği Proteus simülasyon yazılımı kullanılarak doğrulanmıştır. Yazılım tarafında, seri port üzerinden Arduino Mega mikrodenetleyici ile çift yönlü iletişime olanak sağlayan MATLAB Appdesigner kullanılarak bir kullanıcı arayüzü geliştirilmiştir. Geliştirilen görme alanı test sistemi, uzman teknik personel gerektirmeyen, düşük maliyetli, kurulumu kolay, taşınabilir ve güvenilir bir sistemdir. Tasarım ticari cihazlarla karşılaştırıldığında, HFA cihazlarındaki uyaran projeksiyonuyla ilişkili motor gürültülerini ortadan kaldırarak sessiz çalışmasıyla kullanıcılar için daha az dikkat dağıtıcı hale gelmektedir. Bu çalışma, potansiyel klinik tanı ve hasta eğitimi uygulamalarıyla, geleneksel görme alanı test cihazlarına uygun maliyetli, kullanıcı dostu ve taşınabilir bir alternatif sunmaktadır.

Anahtar Kelimeler

• Görme alanı testi
• Glokom Tanısı
• Düşük Maliyetli Tıbbi Cihaz
• Humphrey Alan Analizörü

Kaynakça

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