CT/MRI Society Case of the Month
January 2007
Sponsored by Eklin Medical Systems
Patient Identification Number: CTMRSOC1
Patient Surname Code: CTMRSOC
Patient First Name Code: MATTOON
Accession Number: JAN07
Contributor: John Mattoon/Shannon Holmes
Contributor’s Affiliation: WSU
Species: Canine
Breed: Siberian husky
Age at exam: 17 years
Gender: female spayed
Presenting signs and pertinent history:
Chronic weight loss & inappetence 2 years. Unable/reluctant to stand, prefers lateral recumbency. Thyroid supplementation for several years.
Clinical/Neuro Findings:
Severely emaciated and dehydrated.. Recumbent but responsive. Conscience proprioceptive deficits all four limbs, absent menace response and miotic pupils. Crossed extensor reflex in pelvic and thoracic limbs. 13.1 kg body weight. Normal respiratory rate, heart rate 130 bpm, body tempaerture 100.5 F.
Relevant Laboratory data:
Moderate elevations in ALT, AP, decreased total protein (albumin and globulin); moderate lymphopenia and mild anemia.
Primary clinical rule-out pre imaging:
Starvation
Modality: MRI
Manufacturer: Philips
Model/Field Strength: 1T
Sequences Acquired:
T1 (pre- and post-gadolinium [3 cc]), T2, FLAIR
CT/MR Findings:
Brain
1. The brain parenchyma displays good symmetry and there is mild-to-moderate dilation of the third and lateral ventricles.
2. On FLAIR-weighted sequences, there are multiple ill-defined hyperintense areas that predominantly localize to the white matter, seen in the coronal radiation, periventricular white matter of the lateral ventricles, left intrathalamic adhesion and the central cerebellum. The hyperintense lesions are asymmetric and subjectively the right cerebral hemisphere is mildly more affected. Following the administration of gadolinium, no focus of contrast enhancement is identified. Thus, these lesions likely represent foci of metabolic parenchymal derangement resulting in cytotoxic or hypo-osmotic edema. The integrity of the blood-brain barrier appears to be maintained.
3. Non-contrast enhancing fluid is seen in the right tympanic bulla. No change is seen in the mucosa or osseous structures of the tympanic bulla.
4. As noted on physical examination, there is marked bilaterally symmetric atrophy of the masticatory musculature.
MR Assessment:
Multifocal diffuse white matter disease-suspect edema. Wernicke encephalopathy/thiamine (B1) deficiency as reported in human medicine is a primary differential diagnosis given the emaciated state of the patient. Otitis media, right.
Post Imaging Management:
Controlled feedings in hospital with thiamine supplementation for 1 week. Curiously and for undetermined reasons, this patient ate ravenously in hospital, but simply refused to eat anything at home. The patient died one week following discharge.
Outcome:
Death. Necropsy was not allowed.
Final Diagnosis based on all diagnostic tests and outcome:
Starvation encephalopathy
Comments:
The diagnosis of starvation encephalopathy is presumptive. The MRI findings in this patient show some similarity to Wernicke encephalopathy (WE) as reported in human hunger strike patients (see article below by Unlu et al, Eur J Radiol). Thiamine deficiency is typically associated with chronic alcohol abuse, but can be seen in other debilitating conditions in which sufficient thiamine is not ingested or absorbed. Thiamine is necessary for proper maintenance of cellular membrane osmotic gradients.
References: wernicke_enceph_mri.pdf