Video-Assisted Thoracoscopic Resection of a Noninvasive Thymoma in a Cat with Myasthenia Gravis Using Low-Pressure Carbon Dioxide Insufflation

Vet Surg. 2016 Nov;45(S1):O28-O33. doi: 10.1111/vsu.12504. Epub 2016 Jul 11.

Abstract

Objective: To report the use of low-pressure carbon dioxide insufflation during video-assisted thoracoscopic surgery for resection of a noninvasive thymoma in a cat with secondary myasthenia gravis.

Study design: Clinical case report.

Animal: Client-owned cat.

Methods: An 11-year-old castrated male domestic shorthair cat was examined for generalized weakness, voice change, hypersalivation, hyporexia, vomiting, coughing, and gagging. Thoracic ultrasound revealed a cranial mediastinal mass for which cytology was consistent with a thymoma (or lymphoid tissue). Acetylcholine receptor antibody concentration was elevated at 3.16 mmol/L (reference interval < 0.3 mmol/L). Thoracic computed tomography showed two round, contrast-enhancing structures in the cranioventral mediastinum identified as the sternal lymph node and a cranial mediastinal mass (11 × 17 × 24 mm). A presumptive diagnosis of thymoma with paraneoplastic myasthenia gravis was made and surgical resection of both mediastinal masses was recommended.

Results: Video-assisted thoracoscopic resection of the cranial mediastinal mass and sternal lymph node were performed with low-pressure carbon dioxide insufflation maintained at an intrathoracic pressure of 2-3 mmHg. The cat recovered from surgery without serious complications. Nineteen months after surgery, the cat developed hind limb stiffness. Thoracic radiographs ruled out a cranial mediastinal mass or megaesophagus. Acetylcholine receptor antibody concentration remained elevated at 2.72 mmol/L.

Conclusion: Low-pressure thoracic insufflation facilitated video-assisted thoracoscopic resection of cranial mediastinal masses in this cat.

Publication types

  • Case Reports

MeSH terms

  • Animals
  • Carbon Dioxide*
  • Cat Diseases / diagnosis
  • Cat Diseases / surgery*
  • Cats
  • Insufflation / veterinary*
  • Male
  • Myasthenia Gravis / veterinary
  • Thoracic Surgery, Video-Assisted / veterinary*
  • Thymectomy / veterinary*
  • Thymoma / diagnosis
  • Thymoma / surgery
  • Thymoma / veterinary*

Substances

  • Carbon Dioxide