Small Animals Fracture Repair

Radiographic Interpretation of the thorax

Figure 61:

Beagle dog, female, 8 years old

History:

Large abdomen for 1 month and depressed

X-ray image (only DV direction) was taken.

What do you see from this Image? What should be done next?

Clinical signs : cough, large abdomen + weight loss

Radiographic Findings :

- Generally increased opacity in the thorax
- Enlarged heart, especially right heart enlargement resulting the "reverse D" heart shape
- Prominence of Main Pulmonary Artery (MPA)
- and pulmonary arteries especially those in the left caudal lung lobe
- Lung shows "Vascular Pattern" (increased size and irregular shape of pulmonary arteries)

Diagnostic Impression:

- Right heart enlargement and vascular lung disease associated with prominent MPA, probably caused by Heart Worm Desease (HWD). Sonographic study will reveal the numbers of adult Dilofilaria immitus in the right atrium and MPA.

Differencial Diagnosis:

- HMD (D. immitus infection), Pulmonary Stenosis, or their combination

Diagnosis:

- Heart worm disease (D. immitus infection)

Figure 62:

This dog was anoretic and showed respiratory distress.

 Radiographic findings and interpretation:

VD view

Increased opacity of the left cranial lung lobe that showing pulmonary edema (you can see air bronchogram).

Lateral View

Increased opacity around carina whch suggests enlargement of hilar lymph nodes.

Figures 63, 64:

Signalment
3 year-old female spayed domestic short-haired cat

History
anorexia,coughing,depression for 2 days

Physical Exam
Pink mucous membranes
Crackles ausculted cranioventrally on right side
Respiratory rate was 80 breaths per minute

Radiographs made: Lateral and ventrodorsal projections of the thorax.

Findings:

Diffuse, non-homogenous radiopacity.
Opacities confined to peribronchial region
( seen end-on as "donuts").

Pulmonary vessels difficult to visualize.

These findings are characteristic
of a bronchial pulmonary pattern.

Differential Diagnosis:

Chronic Bronchitis (chronic form of "Feline Asthma")

Etiology: initially allergic

Secondary bacterial infections common

Infectious Tracheobronchitis

Virus,bacteria,mycoplasma, chlamydia

Parasitic Disease

Aelurostrongylus abstrusus
Capillaria aerophilia
Toxoplasma gondii

Inhalation of Toxins

Atypical Pulmonary Edema

Bronchogenic Carcinoma (early)

Figures 65, 66, 67:

Radiographic Studies
Lateral and ventrodorsal projections of the thorax

Signalment
2 year-old female domestic cat.

History
Cat vomiting for 3 days.

Physical Exam
Nothing abnormal was noted on abdominal palpation.

Normal renal size and shape.

The small intestines are "bunched" into the mid-abdomen on the survey radiographs.
This is commonly found in obese cats and must be distinguished  from abnormal "bunching" that occurs with linear foreign bodies.
In the case of linear foreign bodies, there usually will be an abnormal curvature of the involved loops ("hairpin" turns) and some excess gas within the lumen.

Opaque material dorsal cranial to the urinary bladder most likely represents feces in the colon.

A barium study was performed.

Lateral and ventrodorsal radiographs taken twenty minutes after oral barium administration.

At twenty minutes the barium only proceeds to the ascending duodenum where it appears to come to a site of complete obstruction. The shape of the distal column of contrast suggests a circular filling defect. The barium study confirms the suspicions from the findings in the survey radiographs of a distended small  bowel loop in the mid-abdomen.

Notice the peristaltic contractions within the pyloric antrum; it is normal at its near midline location.

At surgery a polyethylene ball bearing was removed from the distal duodenum.

Figures 68, 69, 70:

Radiographic Studies
Lateral projection of the thorax

Signalment
6 year-old male dog.

History:
No prior history was available.

Physical Exam
Presented for cardiac evaluation with a grade II-III/V holosystolic murmur, ouder on the left, was ausculted.

 This size,11.0 vertebrae, was considered to be at the high end of the normal ange for an athletically active whippet.

Echocardiography showed mild mitral regurgitation and mild enlargement of the left atrium. The patient was diagnosed with
Chronic Valvular Disease, and was monitored regularly by auscultation, degree of exercise intolerance and radiography.

Well beyond normal, with VHS of 12.5 measured on the radiograph. The mitral regurgitation murmur was louder, at about IV/V.

Five months later, in October 1994, the patient started showing acute signs of exercise intolerance,coughing and anorexia. His VHS was measured at 13.1.

At this time, echocardiography was performed again, showing profound dilation of the left atrium and the diameter of the mitral valve annulus, with severe mitral regurgitation. Pharmacological intervention was used to stabilize the patient, and a few weeks later mitral annulus purse-string surgery was performed due to the rapid clinical deterioration observed in the preceding few months, and the concomitant cardiac enlargement measured in the last five months.

Vertebral Heart Size (VHS)
A Method for Measuring the Size of the Canine Heart in Lateral Radiographs

Differences in the thoracic confirmation of various dog breeds have made previous methods used for estimating cardiac enlargement of limited value. A study by Buchanan and Bücheler (JAVMA, volume 206,#2, January15,1995, pp.194-199) provides a radiographic method to:

• quantify overall heart size for a given patient

• determine if this patient's heart size is within the normal population distribution

• permit ongoing radiographic monitoring of changes in heart size.

The VHS method measures heart size in two dimensions on the lateral view of thoracic radiographs:

The long axis is measured from the ventral border of the left mainstem bronchus (cranioventral border of the carina) to the cardiac apex (the most distal point on the ventral contour of the cardiac radiographic image).

The short axis is measured at the widest point of the cardiac image on a line perpendicular to the long axis.

The two measurements are then compared to the vertebrae starting at the cranial edge of T4, and a result, expressed in units of vertebral lengths, is obtained for each axis. The sum of the measurements on both axes constitute the VHS.

The criterion established by the study is that the upper limit for most dogs is 10.5 vertebral lengths. ( Possible exceptions: 11 lengths being the high normal for a breed with a short thorax, such as the miniature schnauzer, and 9.5 for a breed with a long thorax, such as the dachshund. The lower normal limit is 8.5 vertebral lengths.

In addition to a initial measurement of heart size, the VHS method is useful for periodic monitoring of heart size with the progression of heart disease, as well as in the response of a patient to therapy.

Figure 71: Tracheal collapse due to incomplete tracheal rings (Courtesy of A.G. Schiller, L.C. Helper, and E. Smail, University of Illinois and J Am Vet Med Assoc.).

Figure 72: Lateral chest radiograph of a mature boxer, demonstrating extreme thickening of the bronchial walls. This change is best seen involving the apical and cardiac main stem branchi. The dog had allergic bronchitis.

Figure 73: Localized pneumonia in the left lung lateral to the hilus. Air bronchograms are visible.

Figures 74, 75: Pulmonary edema. There is a diffuse generalized pulmonary infiltrate involving all lung lobes. Air branchograms are visible in both lungs in all lobes.

Figure 76: Malignant disease that metastasized from the skin. The radiographic appearance is typical of carcinomatous metastases.

Figure 77: Metastatic malignant melanoma. The size and border of the relatively small number of lesions seen is typical of sarcomatous metastases.

Figure 78: Metastatic fibrosarcoma. The smooth border of this metastatic lesion is typical of sarcomatous metastases. Three lesions are present. Two are superimposed.

Figure 79: Lymphosarcoma with a lymphatic spread throughout the lungs. It has a finely granular reticulated appearance. This is a rare manifestation of a lymphosarcoma. There were neoplastic masses in the abdomen.