Radiographic identification of the equine dorsal and ventral nasal conchal bullae

Abstract

Summary The recent understanding that pathology of the nasal dorsal (DCB) and ventral (VCB) conchal bullae can be a common and underdiagnosed cause of unilateral nasal discharge in horses, has generated new interest in these structures. The normal computed tomographic anatomy of the bullae has been described in detail; however, computed tomography facilities are still limited to referral centres, and radiography remains the primary diagnostic imaging modality for most equine practitioners. The purpose of this descriptive imaging study was to describe the radiographic anatomy and limits of both DCB and VCB in equine cadaver skulls. The heads of 10 horses (7 horses, 3 ponies) of unknown age were transected sagittally in the midline, and five radiographic projections (left and right laterolateral, left and right latero30°dorsal–lateroventral oblique and dorsoventral) of the sinuses and nasal cavities were obtained, before and after the placement of stainless steel wire moulded inside the bullae. The radiographic appearance of the VCB and DCB was evaluated on both plain and wire radiographs, assessing their anatomical limits in relation to the cheek teeth and describing the variations related to age and type of horse. The radiographs allowed correct identification of the rostral and caudal limits of the DCB and of the rostral limit of the VCB in the majority of the horse heads. Mild variations in the radiographic appearance of the bullae between horse and pony heads were noted. The laterolateral projections resulted in the best visualisation of the bullae in all the heads used in the study. This study showed that the VCB and DCB are radiographically identifiable on plain radiographs in most mature horses, and that pathology of these structures may be identifiable using radiography.

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

“…Donkeys and Shetland ponies have a shorter but wider skull than larger popular equine breeds (Table 4). Giavotto and Barakzai (2017) found slight variations in the radiographic appearance of the bullae between horses and pony heads.…”

“…Giavotto and Barakzai (2017) found slight variations in the radiographic appearance of the bullae between horses and pony heads. They assumed different nasal profiles and a ‘dome‐shaped’ head in ponies.…”

“…In large breed horses, conformation of the skull (Evans & McGreevy, 2006) as well as the conchal sinuses and bullae (Finnegan et al., 2011; Froydenlund et al., 2015; Liuti et al., 2016; Giavotto & Barakzai, 2017) as well as the sinonasal communication (Tatarniuk et al., 2010; Brinkschulte et al., 2014) were already described, including measurements of skull dimensions. In contrast, the size and dimensions of conchal sinuses and bullae in smaller breeds like ponies are rarely reported and there is a lack of knowledge concerning this area of research.…”

Surgical management of a sinonasal angiomatous polyp and associated cyst involving the paranasal sinuses and nasal cavity via standing axial rhinotomy

“…Empyema of the nasal conchal bullae (dorsal and ventral) has been described in the literature as a cause of chronic unilateral nasal discharge (Dixon et al 2015). Recently, their anatomy and radiographic appearance (standard radiography and CT) has been described in detail (Liuti et al 2016; Giavitto and Barakzai 2019). Anatomical location of the DCB and VCB in this case was found to match those described in the literature.…”

Computed Tomographic Assessment of Individual Paranasal Sinus Compartment and Nasal Conchal Bulla Involvement in 300 Cases of Equine Sinonasal Disease

“…Partly for these reasons, equine nasal disease has been a neglected clinical area until recently. The use of CT has recently allowed new anatomical studies of this area, especially of the hitherto poorly described NCBs (24,25), that in turn has allowed these structures now to be more clearly radiographically imaged (28). Most significantly, CT imaging has been proven invaluable in identifying intercurrent nasal disorders in horses with sinus disease, especially the presence of NCB infections (11,(24)(25)(26) and also sino-nasal fistulae (26).…”