An anatomical study of the dorsal and ventral nasal conchal bullae and middle nasal conchae in normal Shetland ponies: Computed tomographic anatomical and morphometric findings

Abstract

Equine paranasal sinuses are susceptible to inflammation. Insufficient drainage through the nasal passages and meatus may lead to the accumulation of inspissated purulent discharge. Particularly in ponies, these anatomical structures are suspected to be relatively small. To date, there are no reports considering the morphology of nasal conchal bullae in small horse breeds such as Shetland ponies. The aim of the present study was to How to cite this article: Gerlach K, Vervuert I, Gittel C, et al.An anatomical study of the dorsal and ventral nasal conchal bullae and middle nasal conchae in normal Shetland ponies:Computed tomographic anatomical and morphometric findings.

An anatomical study of the skull, the dorsal and ventral nasal conchal bullae and paranasal sinuses in normal Noma horses: Computed tomographic anatomical and morphometric findings

“…In our study, we found that Noma horses had a relatively longer nasal length than cranial length, which is clearly indicated by the cranial length/nasal length quotient of 0.90, compared with 0.96 in large breeds (Evans & McGreevy, 2006), 1.06 in Shetland ponies (Gerlach et al, 2021), and 1.08 in donkeys (Zhu et al, 2014) (Table 5). Furthermore, the skull index of Noma horses was the shortest in comparison with that of the other breeds, apart from large breeds.…”

“…Correlations between the length measurements were calculated using Spearman's rank correlation coefficient, which can be interpreted as follows: 0.8 ≤ | r | ≤ 1.0, very strong; 0.6 ≤ | r | < 0.8, strong; 0.4 ≤ | r | < 0.6, moderate; 0.2 ≤ | r | < 0.4, weak; and 0.0 ≤ | r | < 0.2, very weak (| r | represents the absolute value of the correlation coefficient). On considering the different conformations of the skull by evaluating the relationships between bulla dimensions, ‘adjusted’ measurements of the DCB and VCB dimensions were calculated by dividing the individual bulla length by skull length 2 and multiplying the result into 100 (Froydenlund et al, 2015; Gerlach et al, 2021). Correlations between the volumes, head length and head width were calculated using Spearman's rank correlation coefficient.…”

“…These images were used to measure the nasal dorsal conchal bulla (DCB, Bulla conchalis dorsalis) and ventral conchal bulla (VCB, Bulla conchalis ventralis) with the help of a Digital Imaging and Communications in Medicine (DICOM) viewer (OsiriX MD; Pixmeo SARL). The means and ranges were calculated for each linear measurement in accordance with the process used in large breed horses (Liuti et al, 2016) and Shetland ponies (Gerlach et al, 2021).…”

“…The whole procedure was performed in accordance with previous reports (Brinkschulte et al, 2013;Köhler et al, 2021). Gerlach et al, 2021). Correlations between the volumes, head length and head width were calculated using Spearman's rank correlation coefficient.…”

“…Therefore, investigations of the paranasal sinuses and cavities have been widely performed with the help of CT in large horses (Dixon et al, 2020; Ostrowska et al, 2020). Moreover, the conformation of the skull in smaller horse breeds, including Shetland ponies (Gerlach et al, 2021; Köhler et al, 2021) and donkeys (El‐Gendy et al, 2014; Zhu et al, 2014), was investigated, and these breeds were reported to have different characteristics from those of the large horse breeds (Evans & McGreevy, 2006; Froydenlund et al, 2015). To the best of our knowledge, no investigation has been conducted on whether the skull and nasal morphology of Noma horses has arisen from different phylogenetic trees from those of the abovementioned large and smaller breeds.…”