The Agreement of Intraocular Pressure Measurement in Healthy Merinos Sheep Using Rebound Tonometer (Tonovet®) and Applanation Tonometer (Tono-Pen VetTM)

Yıl 2024, , 184 - 188, 28.11.2024

Sıtkıcan Okur , Latif Emrah Yanmaz , Ömer Tarık Orhun , Yakup Kocaman , Ayşe Gölgeli Bedir , Ferda Turgut , Mümin Gökhan Şenocak , Esra Modoğlu , Ugur Ersoz

https://doi.org/10.36483/vanvetj.1513839

Öz

The assessment of intraocular pressure (IOP) holds significant importance in ophthalmology as a crucial diagnostic tool for various ocular disorders. This study aimed to evaluate the agreement between rebound (TonoVet®, TV) and applanation (Tono-Pen Vet™, TPV) tonometers in measuring IOP in healthy Merino sheep. 155 healthy Merinos (80 males, 75 females) with a mean weight of 54.4±8.7 kg, aged 24±6 months, were included in the study. IOP was measured between 9:00 and 11:00 am using both the rebound and applanation tonometers. The rebound tonometer was used first, followed by the applanation tonometer. A total of 620 readings (310 readings for each tonometer) were obtained from the two devices. No statistical differences were noted between the mean IOP measurements of the right and left eyes for both tonometers (p>0.05). However, there was a significant difference in the mean IOP measurements between the TV (11.8±2.3 mmHg) and the TPV (13.9±2.9 mmHg) tonometers (p<0.001). The concordance correlation coefficient indicated weak agreement strength (ρc=0.319, CI 95% = -0.169 to 0.455) between the TV and TPV. The mean difference in bias and the 95% limits of agreement for the differences between TV and TPV were -2.1 mmHg (-9.0 to 3.5 mmHg). The regression equation derived from a Bland-Altman plot, describing the relationship between the two tonometers, was Y = 1.43 - 0.33X (Y = TV and X = TPV). In conclusion, the TPV measured higher IOP values compared to the TV, and due to the significant bias and limits of agreement, the two tonometers should not be used interchangeably for IOP measurement in Merino sheep.

Anahtar Kelimeler

Applanation, Intraocular pressure, Rebound, Sheep, Tonometer.

Sağlıklı Merinos Koyunlarında Rebound Tonometre (Tonovet®) ve Applanasyon Tonometresi (Tono-Pen VetTM) Kullanılarak Yapılan Göz İçi Basıncı Ölçümlerinin Uyumu

Öz

Göz içi basıncının (GİB) değerlendirilmesi, çeşitli oküler hastalıklar için önemli bir teşhis aracı olarak oftalmolojide büyük önem taşımaktadır. Bu çalışmanın amacı, sağlıklı Merinos koyunlarında GİB ölçümünde rebound (TonoVet®, TV) ve aplanasyon (Tono-Pen Vet™, TPV) tonometreleri arasındaki uyumu değerlendirmektir. Ortalama 54.4±8.7 kg ağırlığında, 24±6 aylık, 155 sağlıklı Merinos (80 erkek, 75 dişi) koyunu çalışmaya dahil edilmiştir. GİB sabah 9:00 ile 11:00 arasında hem rebound hem de aplanasyon tonometreleri kullanılarak ölçülmüştür. IOP ölçümleri için önce rebound, ardından aplanasyon tonometresi kullanıldı. İki cihazdan toplam 620 okuma (göz başına 310 okuma) elde edilmiştir. Her iki tonometre için sağ ve sol gözlerin ortalama GİB ölçümleri arasında istatistiksel bir fark kaydedilmemiştir (p>0.05). Ancak, TV (11.8±2.3 mmHg) ve TPV (13.9±2.9 mmHg) tonometreleri arasında ortalama GİB ölçümleri açısından anlamlı bir fark belirlendi (p<0.001). Çalışma verileri, korelasyon katsayısının TV ve TPV arasında zayıf uyum gücü (ρc=0.319, CI %95 =-0.169 ila 0.455) olduğunu göstermiştir. TV ve TPV arasındaki farklar için ortalama yanlılık farkı ve %95 uyum sınırları -2.1 mmHg (-9.0 ila 3.5 mmHg) olarak belirlendi. İki tonometre arasındaki ilişkiyi tanımlayan Bland-Altman grafiğinden elde edilen regresyon denklemi Y = 1.43 – 0.33X (Y = TV ve X = TPV) olarak tanımlandı. Sonuç olarak, TPV, TV'ye kıyasla daha yüksek GİB değerleri ölçmüştür ve önemli sapma ve uyum sınırları nedeniyle, iki tonometre Merinos koyunlarında GİB ölçümü için birbirinin yerine kullanılmamalıdır.

Anahtar Kelimeler

Aplanasyon, Intraoküler basınç, Koyun, Rebound, Tonometre.

Kaynakça

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