Abstrakti
Introduction: Cataract extraction and artificial intraocular lens implantation is one of the most frequent and successful ophthalmic surgical procedures done today. One major challenge associated with cataract surgery is the accuracy of the intraocular lens power calculation necessary for attaining the desired post-operative refraction and this depends on accurate determination of pre-operative biometric data especially axial length.
Aim: The aim of the study was to compare the ultrasound and optical measurement of axial lengths (AXL) among Pre-operative Cataract Patients in the Department of Ophthalmology, Lagos University Teaching Hospital (LUTH), Lagos.
Methods: The study was a comparative cross-sectional study carried out among pre-operative cataract patients aged 40 years and above. All participating patients had axial length measurement with IOL Master, immersion ultrasound technique and contact ultrasound technique. Equipment used were SW-2100 Ophthalmic A/B Scan (Tianjin Suowei Electronic Technology Co., Ltd, China), Immersion Scleral Shell and IOL Master (Carl Zeiss Meditec AG, Jena, Germany).
Results: One hundred and thirteen eyes of 67 patients were included in the study and the mean age was 61.15 years (SD= 10.78 years). Axial lengths values with IOL Master were the highest with mean values of 23.72+/-1.13mm, followed by the immersion ultrasound technique with mean values of 23.31+/-0.91mm. The axial length by the contact ultrasound technique was the least with mean values of 23.28+/-1.04mm.
Conclusion: The difference in axial length measurements between the optical biometry and the two ultrasound techniques was significant.
Keywords: Axial length, ultrasound biometry, optical biometry, contact technique, immersion technique, IOL Master.
Résumé
Introduction: L’extraction de la cataracte et l’implantation des lentilles intraoculaires artificielles sont l’une des interventions chirurgicales ophtalmiques les plus fréquentes et les plus réussies à ce jour. Un défi majeur associé à la chirurgie de la cataracte est la précision du calcul de la puissance de la lentille intraoculaire nécessaire pour atteindre la réfraction postopératoire souhaitée, ce qui dépend de la détermination précise des données biométriques préopératoires, en particulier de la longueur axiale.
Objectif: Le but de l’étude était de comparer les mesures ultrasonores et optiques des longueurs axiales (AXL) chez les patients préopératoires de la cataracte au département d’ophtalmologie à l’hôpital d’enseignement universitaire de Lagos (LUTH) à Lagos.
Méthodes: L’étude était une étude transversale comparative menée auprès de patients atteints de cataracte préopératoire âgés de 40 ans et plus. Tous les patients participants ont eu une mesure de longueur axiale avec IOL Master, une technique par ultrasons par immersion et une technique par ultrasons par contact. Les matériels utilisésétaient le scanner SW-2100 ophtalmique A/B (Tianjin SuoweiTechnologie Electronique Co., Ltd, Chine), Immersion Scléral Shell et IOL Master (Carl Zeiss Meditec AG, Jena, Allemagne).
Résultats: Cent treize yeux de 67 patients ont été inclus dans l’étude et l’âge moyen était de 61,15 ans (écart-type = 10,78 ans). Les valeurs de longueur axiale avec IOL Master étaient les plus élevées avec des valeurs moyennes de 23,72 ± 1,13 mm, suivies par la technique àultrasons par immersion avec des valeurs moyennes de 23,31 ± 0,91 mm.La longueur axiale par la technique à ultrasons de contact était la plus faible avec des valeurs moyennes de 23,28 ± 1,04 mm.
Conclusion: La différence de longueur axiale entre la biométrie optique et les deux techniques ultrasonores était significative.
Mots - clés: Longueur axiale, biométrie à ultrasons, biométrie optique, technique de contact, technique d’immersion, IOL Master.
Correspondence: Dr. A.S. Alabi, Me Cure Eye Centre, Oshodi, Lagos State, Nigeria. E-mail: alabisundade@yahoo.com.
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