Ophthalmic ultrasound of dogs with different skull conformations

Abstract

The aim of this study was to establish mean values for intraocular structures and analyse if the differences are present for different skull conformations in dogs. In this study, 30 dogs were selected and distributed into three groups according to skull conformation; thus, group 1 (G1) was composed of brachycephalic dogs, group 2 (G2) was composed of mesocephalic dogs and group 3 (G3) was composed of dolichocephalic dogs. A and B-mode ultrasound was performed simultaneously for obtainment of measurements relating to anterior chamber depth (D1); lens thickness (D2); vitreous chamber depth (D3); and the axial length of the eye (D4). No differences were observed when comparing left and right eyes of dogs within the same skull conformation group (p>0.05). Differences were observed when comparing D3 and D4 between groups G2 and G3 (p<0.05). Skull conformation of brachycephalic dogs did not influence intraocular measurement values when compared to dolicephalic and mesocephalic dogs. Skull conformation of dolichocephalic dogs had an influence in values of vitreous chamber and the complete length of the eye when compared to mesocephalic dogs.Key words: brachycephalic, dolichocephalic, eye, mesocephalic, ultrasound Ultrassonografia oftálmica em cães com diferentes conformações cranianas RESUMOO objetivo deste estudo foi estabelecer valores médios para as estruturas intraoculares e analisar se existem diferenças entre eles nas diversas conformações cranianas de cães. Foram selecionados 30 cães alocados em três grupos, de acordo com a conformação craniana; assim, o grupo 1 (G1) foi composto por cães braquicefálicos, o grupo 2 (G2) por cães mesocefálicos e o grupo 3 (G3) por cães dolicocefálicos; ultrassonografia em modo A e B foi realizada simultâneamente para obtenção de medidas relacionadas à profundidade de câmara anterior (D1), espessura de lente (D2), profundidade de câmara vítrea (D3) e comprimento axial do bulbo do olho (D4); diferenças não foram observadas quando comparados olhos direitos e esquerdos de cães com mesma conformação craniana (p > 0,05). Diferenças foram constatadas na comparação entre D3 e D4 dos grupos G2 e G3 (p < 0,05); a conformação do crânio braquicefálico não influenciou nos valores das medidas intraoculares quando comparados aos valores encontrados para cães dolicocefálicos e mesocefálicos; a conformação do crânio dolicocefálico influenciou nos valores das medidas intraoculares de profundidade de câmara vítrea e profundidade do bulbo do olho quando comparados aos valores encontrados para cães mesocefálicos.

Ocular echobiometry and head measurements in Jersey cattle from different age groups

“…Among the biometry and head measurements relation studied, a positive correlation was observed between the AxL versus the total length and width of the head. Studies in humans (Larsen, 1979), dogs (Beserra et al., 2009; Toni et al., 2013) and cats (Ferreira et al., 2014) reported similar relations between the AxL of the eye and the head measurements. In addition, a positive correlation existed among the ocular radius and the performance, vision and behaviour of dogs (Gácsi et al., 2009; McGreevy et al., 2004).…”

“…The VC measurements in adult cattle were similar to animals of the same breed (1.62 cm) (Potter et al., 2008), greater than those found for the Holstein (1.46 cm) (Potter et al., 2008) and Angus (1.37 cm) (El‐Maghraby et al., 1995) breeds, and less than those found for buffaloes (1.67 cm; (Assadnassab & Fartashvand, 2013) 1.75 cm (Kassab, 2012)). Breed diversity has been suggested as a cause for the differences observed in studies with cattle (Potter et al., 2008) and dogs (Beserra et al., 2009; Toni et al., 2013). The similarities and differences between the breeds may be the cause of the discrepant values obtained in the VC, AxL, AC and LT measurements.…”

“…The present study was conducted with Jersey cattle, which were chosen for their phenotypic homogeneity, in addition to being considered remarkable animals for milk production, feed conversion, precocity, Ocular structures such as the cornea, anterior chamber, anterior and posterior lens capsules, vitreous chamber and posterior wall presented similar echogenicity and echotexture to those of other mammals (Assadnassab & Fartashvand, 2013;Beserra et al, 2009;Ekesten & Torrång, 1995;Ferreira et al, 2014;Gonçalves et al, 2009;Kassab, 2012;Laus et al, 2013;McMullen & Gilger, 2006;Mirshahi et al, 2014;Plummer et al, 2003;Potter et al, 2008;Ribeiro et al, 2009; Silva et al, 2010; Squarzoni, 2011; Toni et al, 2013;Tuntivanich et al, 2007) and wild animals (Bapodra et al, 2010;Harris et al, 2008;Hernández-Guerra et al, 2007;Montiani-Ferreira et al, 2008;Rajaei et al, 2016;Ruiz et al, 2015;Squarzoni et al, 2010;Toni et al, 2010). The iris and the ciliary body in the studied cattle were thick and irregular when compared to those of other species such as dogs (Squarzoni, 2011) and humans (Lorente-Ramos et al, 2012;Silva et al, 2011).…”

“…Thus, studies related to normal eye patterns in ruminants are essential for understanding and monitoring (Corrêa et al., 2014; El‐Tookhy & Tharwat, 2013) these conditions and for treating them (Ali et al., 2015). Routine ophthalmologic examination with B‐mode ultrasound has become essential for evaluating the eye and biometry in different species, such as dogs (Beserra et al., 2009; Ekesten & Torrång, 1995; Silva et al., 2010; Squarzoni, 2011; Toni et al., 2013; Tuntivanich et al., 2007), cats (Ferreira et al., 2014; Gonçalves et al., 2009; Mirshahi et al., 2014), goats (Ribeiro et al., 2009), cattle (Potter et al., 2008), buffaloes (Assadnassab & Fartashvand, 2013; Kassab, 2012), horses (McMullen & Gilger, 2006; Plummer et al., 2003), donkeys (Laus et al., 2013), rabbits (Toni et al., 2010), Asian elephants (Bapodra et al., 2010), ferrets (Hernández‐Guerra et al., 2007), guinea pigs (Rajaei et al., 2016), capybaras (Montiani‐Ferreira et al., 2008), owls (Harris et al., 2008; Squarzoni et al., 2010), penguins (Bliss et al., 2015) and alligators (Ruiz et al., 2015).…”

“…Ocular biometry correlated with head measurements provides important information for preparing ocular prostheses for ophthalmic surgeries such as enucleations and those performed due to bilateral congenital malformations (Ferreira et al, 2014;Larsen, 1979;Mirshahi et al, 2014;Squarzoni, 2011). Head measurements and echobiometry of different breeds can also help with the early diagnosis of ocular diseases, in addition to allowing them to be monitored (Toni et al, 2013). In addition, studies are conducted with cattle to develop ophthalmologic research for humans and other animals (Tektas et al, 2010).…”