Short‐ and long‐term outcome and magnetic resonance imaging findings after surgical treatment of thoracolumbar spinal arachnoid diverticula in 25 Pugs

Abstract Background There is a successful outcome after surgical management of spinal arachnoid diverticula (SAD) in up to 82% of cases. Hypothesis/Objectives We hypothesized that Pugs have favorable short‐term and poor long‐term prognosis after surgical treatment of thoracolumbar SAD. The aim of the present investigation was to describe clinical findings, short‐ and long‐term outcomes, and follow‐up magnetic resonance imaging (MRI) findings in Pugs with thoracolumbar SAD. Animals Twenty‐five client owned Pugs with 12‐month follow‐up information after surgical treatment of thoracolumbar SAD. Methods Multicenter retrospective case series. All medical records were searched for Pugs diagnosed with SAD. Data regarding signalment, history, surgical procedure, outcome, histopathology, and follow‐up MRI results were extracted. Results Mean age at presentation was 7.32 (range 2‐11) years, 80% were males. Short‐term outcome was available in 25 dogs, and improvement was confirmed in 80% of dogs. Long‐term outcome was available in 21 dogs, and deterioration was confirmed in 86% of cases, with late‐onset recurrence of clinical signs after initial postsurgical improvement affecting 85% of Pugs. A moderate correlation (r = 0.50) was found between duration of clinical signs and outcome. In 8 dogs with deteriorating clinical signs, follow‐up MRI revealed regrowth of the SAD in 2 cases, new SAD formation in 2 cases, and intramedullary T2W hyperintensity/syringomyelia in 6 cases. Conclusions and Clinical Importance This study suggests that Pugs with thoracolumbar SAD do not have a favorable long‐term prognosis after surgical treatment for reasons yet to be determined.