Diagnostic outcome of contrast videofluoroscopic swallowing studies in 216 dysphagic dogs

Background Megaesophagus (ME) carries a poor long‐term prognosis in dogs. In people, lower esophageal sphincter (LES) disorders causing functional obstruction are rare causes of ME that may respond to targeted treatment. Functional LES disorders are reported rarely in dogs because of challenges in diagnostic methodologies. Hypothesis/Objectives To identify dogs with videofluoroscopic swallow study (VFSS) features of LES achalasia‐like syndrome (LES‐AS). We hypothesized that dogs with LES‐AS could be distinguished from normal dogs using standardized VFSS criteria. Animals Dogs with LES‐AS by VFSS (n = 19), healthy normal dogs (n = 20). Methods Retrospective study. One‐hundred thirty dogs presented to the University of Missouri Veterinary Health Center (MU‐VHC) between April 2015 and December 2017 for a free‐feeding VFSS; 20 healthy dogs were included as controls. Swallow studies were evaluated for failure of the LES to relax during pharyngeal swallow (LES‐AS). Affected dogs subsequently were evaluated using standardized criteria to identify metrics important for identifying and characterizing dogs with LES‐AS. Results Nineteen dogs with LES‐AS were identified out of 130 VFSS. Megaesophagus was present in 14 of 19 (73.7%) dogs with LES‐AS. A baseline esophageal fluid‐line and “bird beak” were present in 68.4% (95% confidence interval [CI], 47.5%‐89.3%) and 63.2% (95% CI, 41.5%‐84.8%) of affected dogs, respectively. The esophagus was graded as acontractile (8/19), hypomotile (8/19), or hypermotile (3/19). Conclusions and Clinical Importance Dogs with LES‐AS may successfully be identified by VFSS using a free‐feeding protocol. These data are of critical clinical importance because a subpopulation of dogs with functional LES obstruction may be candidates for targeted intervention.

Section: Discussionmentioning

confidence: 99%

Videofluoroscopic swallow study features of lower esophageal sphincter achalasia‐like syndrome in dogs

Grobman

Schachtel²,

Gyawali

et al. 2019

“…Using a protocol that allows dogs to stand and free‐feed, we documented that 61% of dogs with ME that would have been classified as “idiopathic” had underlying LES‐AS. These findings contrast with those of a large study of 216 dysphagic dogs in which VFSS performed with dogs in in lateral recumbency failed to identify any dogs with functional LES obstruction and historical manometric studies that failed to identify functional LES obstruction . Furthermore, the use of unrestrained and free‐feeding VFSS protocols decreases the risk of aspiration to no more than would be expected in the dogs at home.…”

Section: Discussionmentioning

confidence: 99%

“…These findings contrast with those of a large study of 216 dysphagic dogs in which VFSS performed with dogs in in lateral recumbency failed to identify any dogs with functional LES obstruction and historical manometric studies that failed to identify functional LES obstruction. 33,34 Furthermore, the use of unrestrained and free-feeding VFSS protocols decreases the risk of aspiration to no more than would be expected in the dogs at home. To date, no dog at our institution has developed aspiration pneumonia after these unrestrained free-feeding VFSS, including those with ME.…”

Section: Discussionmentioning

confidence: 99%

Mechanical dilation, botulinum toxin A injection, and surgical myotomy with fundoplication for treatment of lower esophageal sphincter achalasia‐like syndrome in dogs

Grobman

Hutcheson

Lever

et al. 2019

Background Megaesophagus (ME) carries a poor long‐term prognosis in dogs. In people, lower esophageal sphincter (LES) achalasia is a rare cause of ME that may respond to targeted intervention. Dogs with lower esophageal sphincter achalasia‐like syndrome (LES‐AS) have been described recently, warranting investigation of analogous targeted treatment. Hypothesis/Objectives Evaluate response of dogs with LES‐AS to LES mechanical dilation and botulinum toxin A (BTA) injections, with or without surgical myotomy and fundoplication. We hypothesized that clinical and videofluoroscopic swallow study (VFSS) features of LES‐AS would improve after treatment targeting functional LES obstruction. Animals Fourteen client‐owned dogs with LES‐AS diagnosed by VFSS. Methods Retrospective study. Dogs diagnosed with LES‐AS underwent treatment between April 2015 and December 2017. Outcome measures included client perception of clinical severity, body weight (BW), body condition score (BCS), regurgitation frequency, and VFSS parameters (ME, esophageal motility, gastric filling). Dogs with positive responses were considered candidates for LES myotomy with fundoplication. Results By a median IQR of 21 (IQR, 14‐25) days after mechanical dilation and BTA, clients reported clinical improvement in 100% of dogs, BW increased 20.4% (IQR, 12.7%‐25%), pre‐ and post‐treatment BCS was 3 (IQR, 3‐4) and 5 (IQR, 4‐5), respectively, and frequency of regurgitation decreased by 80% (IQR, 50%‐85%). Duration of effect was 40 (IQR, 17‐53) days. Despite clinical improvement, ME and abnormal esophageal motility persisted in 14 dogs. Six dogs subsequently underwent myotomy and fundoplication and maintained improvement observed after mechanical dilation and BTA. Conclusions and Clinical Importance Dogs with LES‐AS experienced significant, temporary, clinical improvement after mechanical dilation and BTA. Preliminary results suggest myotomy with fundoplication provide lasting clinical benefit despite persistence of ME.

“…5,9 Imaging findings in dogs with ED are variable, based on the underlying disease, and include morphological abnormalities such as a redundant esophagus, stenosis, stricture, or diverticula as well as functional abnormalities such as ineffective peristaltic waves, bolus retention, prolonged transit time, retrograde esophageal contractions, and GER. 1,10 We have noted subjectively an increase in the number of young brachycephalic dogs presenting for investigation of regurgitation, dysphagia, or both without overt megaesophagus, and with and without overt signs of airway disease. In addition to a high prevalence of endoscopic gastrointestinal (GI) tract lesions previously reported in brachycephalic dogs with brachycephalic obstructive airway syndrome (BOAS), 11 delayed esophageal transit time (ETT), GER, HH, and redundant esophagus also have been reported to be associated with these breeds.…”

Section: Introductionmentioning

confidence: 99%

Retrospective analysis of esophageal imaging features in brachycephalic versus non‐brachycephalic dogs based on videofluoroscopic swallowing studies

Eivers

Rueda

Liuti

et al. 2019

Background Idiopathic esophageal dysmotility (ED) is increasingly recognized in young dogs of brachycephalic breeds. Few studies have objectively associated specific videofluoroscopic swallowing study (VFSS) features with brachycephaly, leading to under‐recognition of ED in brachycephalic breeds. Hypothesis/objectives To describe and compare VFSS in brachycephalic dogs versus non‐brachycephalic dogs presented for dysphagia or regurgitation, and to investigate associations between these imaging findings and patient signalment. Methods Retrospective analysis of VFSS of dogs presented for dysphagia or regurgitation (not megaesophagus) from 2006 to 2017. Cases were divided into brachycephalic and mesaticephalic breeds. The VFSS were reviewed using a standardized protocol by 2 examiners. Esophageal motility was assessed using specific criteria, and particular imaging features were noted and graded. Fisher's exact test was used to determine associations among signalment (including brachycephaly), final diagnosis, outcomes, and ED features. Results Thirty‐six dogs were included (n = 10 normal, n = 26 presumed ED). Twenty dogs (77%) with presumed ED were brachycephalic with a median age of 1 year (range, 0.2‐10.5 years). Most common were prolonged esophageal transit time (ETT; n = 21/26), decreased propagation of secondary peristaltic waves (n = 20/26), and gastroesophageal reflux (GER; n = 18/28). Eight dogs (all brachycephalic) had hiatal herniation (HH). Morphological esophageal variations were only observed in brachycephalic dogs. Brachycephaly was significantly associated with ED ( P = .005), prolonged ETT ( P = .41), GER ( P = .02), and HH ( P = .03). Conclusions and Clinical Importance The majority of dogs with presumed ED was young and brachycephalic and had specific abnormalities that were less frequent in mesaticephalic dogs with regurgitation or dysphagia.