Introduction

• Indications for thoracic radiography   Radiography: thorax   include:
  • Investigation of respiratory signs such as dyspnea   Dyspnea  , sneezing, wheezing.
  • Collapse or syncope.
  • Lethargy or exercise intolerance.
  • Evaluation of suspected cardiac abnormalities   Radiology: cardiac examination  .
  • Thoracic skeleton examinations, eg trauma cases.
• The relative small thorax and the unique anatomical features of the rabbit make thoracic image interpretation a challenge.
• The fundamentals of radiography apply to rabbits as they would in any other species.
• Long-standing illness may be present despite only mild to moderate clinical signs, eg pneumonia.

Any rabbit suffering cardiac and/or respiratory signs is likely to be severely compromised, increasing the difficulty and risks of diagnostic imaging.

• Differentiating signs of physiological stress, eg tachypnea, from signs of disease can be difficult in the rabbit. A thorough clinical history taking and clinical examination will help determine if the patient requires thoracic radiography.

Positioning and radiographic views

• At least one lateral and dorsoventral or ventrodorsal view are required in order to assess the thoracic cavity.
• If only one lateral view is taken, the right lateral is preferred, as this is the most commonly used standard lateral view.
• Retract the forelegs cranially, if possible, to help prevent superimposition of the scapulae over the cranial portion of the thorax.
• A dorsoventral view can be obtained in most rabbits without sedation or anesthesia, so is an option for compromised patients.
• Sedation, eg midazolam   Midazolam  , given at 0.25-1 mg/kg IV or IM, and/or anesthesia is often required in order to obtain adequate views (see Warning above).

Normal anatomy

Heart

Vessels

Mediastinum

Chest wall

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Onuma M, Ono S, Ishida T et al (2010) Radiographic measurement of cardiac size in 27 rabbits. J Vet Med Sci 72 (4), 529-531 PubMed.
• Redrobe S (2001) Imaging techniques in small mammals. Seminars in Avian and Exotic Pet Medicine 10 (4), 187-197 ScienceDirect.
• Clippinger T L, Bennett R A, Alleman A R et al (1998) Removal of a thymoma via median sternotomy in a rabbit with recurrent appendicular neurofibrosarcoma. JAVMA 213 (8), 1140-1143 PubMed.
• DeSanto J (1997) Hypertrophic osteopathy associated with an intrathoracic neoplasm in a rabbit. JAVMA 210 (9), 1322-1323 PubMed.
• Marano G, Formigari R, Grigioni M et al (1997) Effects of isoflurane versus halothane on myocardial contractility in rabbits-assessment with transthoracic two-dimensional echocardiography. Lab Anim 31 (2), 144-150 PubMed.
• Buchanan J W & Bücheler J (1995) Vertebral heart scale system to measure canine heart size in radiographs. JAVMA 206 (2), 194-199 PubMed.
• Vernau K M, Grahn B H, Clarke-Scott H A et al (1995) Thymoma in geriatric rabbit with hypercalcaemia and periodic exophthalmos. JAVMA 206 (6), 820-822 PubMed.
• Kostolich M, Panciera R J (1992) Thymoma in a domestic rabbit. Cornell Vet 82 (2), 125-129 PubMed.
• Toth L A, Olson G A, Wilson E et al (1990) Lymphocytic leukemia and lymphosarcoma in a rabbit. JAVMA 197 (5), 627-629 PubMed.
• Shell LG & Saunders G (1989) Arteriosclerosis in a rabbit. JAVMA 194 (5), 679-680 PubMed.
• Martin M W, Drake P G & Else R W (1987) Congestive failure with atrial fibrillation in a rabbit. Vet Rec 121 (24), 570-571 PubMed.
• Hoover J P, Paulsen D B, Qualls C W et al (1986) Osteogenic sarcoma with subcutaneous involvement in a rabbit. JAVMA 189 (9), 1156-1158 PubMed.
• Gibbs C & Hinton M H (1981) Radiological examination of the rabbit 1. The head, thorax and vertebral column. JSAP 22 (11), 687-703 PubMed.
• Gupta B N (1976) Lymphosarcoma in a rabbit. Am J Vet Res 37 (7), 841-843 PubMed.
• Amand W B, Riser W H & Biery D N (1973) Spontaneous osteosarcoma with widespread metastases in a belted Dutch rabbit. JAAHA 9 (6), 577-581 VetMedResource.

Other sources of information

• Orcutt C (2006) Cardiovascular Disorders. In: BSAVA Manual of Rabbits Medicine & Surgery.2nd edn. Eds: Meredith A & Flecknell P. Gloucester, UK.
• Silverman S (2001) Radiology of the Rabbit Thorax. Presented at: House Rabbit Society Veterinary Conference.
• Stefanacci J D & Hoefer H L (1997) Cardiovascular Disease. In: Ferrets, Rabbits and Rodents. Clinical Medicine and Surgery. Eds:Hillyer E V & Queensberry K E. Philadelphia, Saunders. pp 63-70.
• Stefanacci J D & Hoefer H L (1997) Small Mammal Radiology. In: Ferrets, Rabbits and Rodents. Clinical Medicine and Surgery. Eds: Hillyer E V & Queensberry K E. Philadelphia, Saunders. pp 358-377.