A review of equine paranasal sinusitis. Aetiopathogenesis, clinical signs and ancillary diagnostic techniques

Abstract

Summary The equine paranasal sinuses are air filled cavities of uncertain function that are susceptible to inflammation, usually associated with bacterial infection. A common feature of most types of sinusitis is the accumulation of exudate within the affected sinus and subsequent ipsilateral nasal discharge. Equine sinusitis can have a variety of causes, including primary sinusitis following upper respiratory tract infections, and secondary sinusitis caused by dental infections, intrasinus benign and malignant growths and head trauma.

Comparison between radiography and computed tomography for diagnosis of equine skull fractures

“…). The main limitation of radiography in these complex anatomical regions is a broad variety of opacities, contrary to lesions involving the paranasal sinuses (O'Leary and Dixon ) or the mandible (Huggons et al . ).…”

Acquisition and interpretation of radiographs of the equine skull

“…Free fluid in the maxillary and/or conchofrontal sinuses will typically result in well‐defined air‐fluid interfaces ( Fig ), although with chronic sinusitis, thick or inspissated fluid may not create well‐demarcated flat fluid lines. Other radiographic signs of primary sinusitis include intrasinus radiopacity diffusely throughout the paranasal sinuses, secondary to increased fluid and/or mucosal thickening, septal deviations and bony expansion (Gibbs and Lane ; O'Leary and Dixon ). However, septal deviations can be insignificant radiographic findings in clinically normal horses.…”

“…While once believed to be a disease primarily of young horses, the current literature suggests that there is not an age predisposition for the development of sinonasal cysts (O'Leary and Dixon ). Sinonasal cysts are benign, expansile lesions resulting in decreased airflow, increased respiratory noise, nasal discharge and facial deformity (Lane et al .…”

Endoscópio rígido e flexível na sinoscopia e técnica de triangulação em seios paranasais de equinos

“…Os seios maxilares rostral e caudal estão separados por um septo ósseo, localizado geralmente entre o primeiro e segundo dentes molares (FREEMAN, 1991). A comunicação sinonasal pode ocorrer através de um ou dois orifícios, constituindo uma estreita via de drenagem (1-2 mm) para o aspecto caudal do meato médio nasal (PROBST et al, 2005;DIXON, 2011).…”

“…A exploração cirúrgica pela técnica de sinusotomia pode levar ao diagnóstico defi nitivo, porém, além de ser procedimento invasivo, requer a manutenção do animal sob anestesia geral e apresenta maior risco de complicações no período pós-operatório (RUGGLES et al, 1991;BEARD & HARDY, 2001). Por outro lado, por se tratar de procedimento minimamente invasivo, a sinoscopia pode ser realizada em cavalos sedados, mantidos em posição quadrupedal, permitindo o exame detalhado dos seios paranasais, realização de biópsias e coleta de material para cultura e antibiograma, sendo indicada principalmente nos casos com diagnóstico inconclusivo (RUGGLES et al,1993;O'LEARY& DIXON, 2011). Pequenas intervenções terapêuticas utilizando a sinoscopia para casos de sinusite primária, hemorragia, ou pequenas formações císticas já foram descritas (MARQUES et al, 2001;RUGGLES et al,1993;SILVA et al, 2004;SILVA et al, 2009;DIXON & O'LEARY, 2012;DIXON et al, 2012b).…”