Page 634 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Respir atory system: 3.2 Surgical conditions of the respir atory tr act 609

VetBooks.ir 3.28 3.29

Fig. 3.28 Exophthalmos of the left eye caused by a
neuroendocrine tumour.

Fig. 3.29 Secondary sinusitis, with fluid lines in the
rostral maxillary and conchofrontal sinuses (arrows)
and periapical sclerosis of tooth 109 (arrowheads).

central nervous system to cause a meningoenceph- oblique and open-mouth radiographic views can be
alitis. Exophthalmos is observed with expanding helpful. Lavage of the sinus for several days to help
masses of the paranasal sinuses, commonly neuroen- remove as much fluid and pus as possible prior to
docrine tumours (Fig. 3.28). specific sinus and tooth root radiographic views may
help define specific tooth or sinus problems. Detailed
Differential diagnosis oral examination (plus dental endoscope) and radi-
Primary sinusitis is the principal differential diag- ography should always be combined to increase the
nosis, but a specific diagnosis for secondary sinusitis specificity of a precise diagnosis (Fig. 3.30). The use
is essential to make a treatment plan and prognosis. of scintigraphy in the diagnosis of periapical den-
In secondary sinusitis smaller amounts of fluid are tal infection has declined recently, and the budget
often found in the sinuses, with fluid lines on radio- for advanced diagnostics is now generally directed
graphs (Fig. 3.29). Mycotic sinusitis is an important towards a standing horse CT head scan.
differential diagnosis and can develop as a result of Tumours and cysts can be visible on sinusos-
treatment for a primary sinusitis. copy, although initial lavage of the discharges for
several days may be necessary to ensure adequate
Diagnosis visualisation.
The diagnosis of secondary sinusitis is similar to the
primary version. Radiographic diagnosis of periapi- Management
cal dental infection may not be reliable in some cases, The management of secondary sinusitis depends
particularly when dealing with the caudal maxillary on the underlying disease. If this can be treated,
teeth or cases in younger horses. Specific arcade the underlying sinusitis will usually resolve with