Case Study

Abscess/Fistula of the Right Eye with Secondary Chronic Septic Osteitis in a 12 year old MN Maine Coon cat

History of chronic rhinitis which is only partially responsive to steroids and no improvement with antibiotics Newly developed eye discharge, seems quieter than usual since his last Depo Medrol injection 1 month ago. Taking compounded Baytril, no other medications. Physical Exam: BARH mms pink CRT2s, Matted haircoat, BCS 5/9 – some loss of muscle mass in hind limbs, lost 1.1 lbs since last visit. EENT: Absent menace OD, retinal hemorrhage OD – seen with ophthalmoscope – limited visibility due to patient movement. Fluoro negative OU . OD periocular swelling near medial canthus. Able to retropulse eyes. Mucopurulent nasal discharge especially on the right. Fluoro stain seen from left nostril but not the right. No arrhythmias or murmurs ausculted, referred upper airway noise, no adventitious lung sounds. BP readings averaged 215 systolic, 144 diastolic, MAP of 162 . New problems include – retinal hemorrhage, hypertension (also could be due to stress in office), periorbital swelling. Concern for mass effect, or infectious process impacting right eye.

Image Interpretation

Ultrasound of the right eye –
There was an ovoid mass lesion ventral to the right eye superficial to the zygomatic arch and/or maxillary bone. The lesion measured approximately 1.5 cm in diameter presented a well defined thick echogenic capsule. The lesion content comprised hypoechoic material and multiple foci of echogenic gas causing multipath reverberation acoustic shadowing. The vascularity of the lesion was not assessable as a power or Color Doppler study was not available.
The underlying bone surface presented irregularity with mineralized periostel reactions and small, well defined interruptions.
The described mass lesion was in close proximity to the eye, but did not affect the echoarchitecture of the eye.
A retinal detachment or vitreal chamber hemorrhage was not seen.

DX

The ultrasonographic findings are compatible with an abscess/fistula and secondary chronic septic osteitis

Outcome

As the patient also presents nasal discharge, primary dental disease of the right upper cheek teeth with oronasal fistula is high for potential. A neoplasia with superinfection and necrosis cannot be ruled out theoretically but is low for potential here.
The patient needs a dental examination. Further management has to be tailored to the findings.
The posterior wall of the eye including the retina presented no abnormalities.