This is a short video demonstrating Darwin's scratching habit, which seems unusual with respect to frequency and degree of agitation.
Localization: He scratches on both sides of his body, targeting his ribs, neck, ears and jaw.
Frequency: He always scratches within 30 minutes of waking in the morning. Episodes occur sporadically throughout the day, multiple times each day. He also typically scratches before settling in for the night.
Severity: He usually growls while scratching, and occasionally (~30%) he barks or yelps.
Note: This behaviour consistently occurs every morning, when he is not wearing a collar or harness.
Update May 3, 2010: Darwin was admitted to the Canada West Veterinary Specialists & Critical Care Hospital for an MRI scan last Friday. A total of 109 images of his brain, ears, and spine were obtained.
Diagnosis: Caudal occipital malformation syndrome (also known as COMS, Chiari-like malformation, CM and CLM), with no presence of syringomyelia See update below.
Treatment: A trial course of Gabapentin (75mg PO TID) was recommended as treatment for the neck scratching, since this is likely related to his abnormal anatomy, to be administered three times daily, or tapered and given as needed, depending on it’s efficacy. Recommendation to consider repeating an MRI scan in 6-12 months time to evaluate for any progression of his findings.
Update September 9, 2010: Darwin's MRI images were reviewed by Dr. Nick Sharp at Canada West Veterinary Specialists & Critical Care Hospital today. His review revealed a small syrinx, leading to a diagnosis of syringomyelia to explain Darwin's scratching episodes.