One-health approach to canine cognitive decline: Dogs Overcoming Geriatric Memory and Aging Initiative for early detection of cognitive decline.

Treatment options for human dementia remain limited, and additional research is needed to develop and validate translational models. Canine cognitive decline (CCD) is common in older dogs and a major source of morbidity. The decline includes physiological and behavioral changes comparable to those in humans diagnosed with dementia. There are also corresponding changes in plasma neurodegenerative biomarkers and neuropathology. Biomarkers for both human and canine cognitive decline can be used to identify and quantify the onset of behavioral data suggestive of CCD. Successful correlations would provide reference values for the early identification of neurodegeneration in canine patients. This could allow for the subsequent testing of interventions directed at ameliorating CCD and offer translational value leading to safe and effective treatment of dementia in people. Research can help exploit, track, and provide benefits from the rapid progression of spontaneous naturally occurring CCD in a large heterogenous community of companion dogs. Research efforts should work to deliver information using blood biomarkers, comorbidities, and wearable technologies to track and evaluate biometric data associated with neurodegeneration and cognitive decline that can be used by both human and companion animal researchers. The synergistic approach between human and veterinary medicine epitomized in one health underscores the interconnectedness of the well-being of both species. Leveraging the insights gained from studying CCD can not only lead to innovative interventions for pets but will also shed light on the complex mechanisms of human dementia.

What Is Your Diagnosis?

In collaboration with the American College of Veterinary Radiology.

Yttrium-90 radioembolization as a possible new treatment for brain cancer: proof of concept and safety analysis in a canine model.

PURPOSE: To evaluate the safety, feasibility, and preliminary efficacy of yttrium-90 (90Y) radioembolization (RE) as a minimally invasive treatment in a canine model with presumed spontaneous brain cancers. MATERIALS: Three healthy research dogs (R1-R3) and five patient dogs with spontaneous intra-axial brain masses (P1-P5) underwent cerebral artery RE with 90Y glass microspheres (TheraSphere). 90Y-RE was performed on research dogs from the unilateral internal carotid artery (ICA), middle cerebral artery (MCA), and posterior cerebral artery (PCA) while animals with brain masses were treated from the ICA. Post-treatment 90Y PET/CT was performed along with serial neurological exams by a veterinary neurologist. One month after treatment, research dogs were euthanized and the brains were extracted and sent for microdosimetric and histopathologic analyses. Patient dogs received post-treatment MRI at 1-, 3-, and 6-month intervals with long-term veterinary follow-up. RESULTS: The average absorbed dose to treated tissue in R1-R3 was 14.0, 30.9, and 73.2 Gy, respectively, with maximum doses exceeding 1000 Gy. One month after treatment, research dog pathologic analysis revealed no evidence of cortical atrophy and rare foci consistent with chronic infarcts, e.g., < 2-mm diameter. Absorbed doses to masses in P1-P5 were 45.5, 57.6, 58.1, 45.4, and 64.1 Gy while the dose to uninvolved brain tissue was 15.4, 27.6, 19.2, 16.7, and 33.3 G, respectively. Among both research and patient animals, 6 developed acute neurologic deficits following treatment. However, in all surviving dogs, the deficits were transient resolving between 7 and 33 days post-therapy. At 1 month post-therapy, patient animals showed a 24-94% reduction in mass volume with partial response in P1, P3, and P4 at 6 months post-treatment. While P2 initially showed a response, by 5 months, the mass had advanced beyond pre-treatment size, and the dog was euthanized. CONCLUSION: This proof of concept demonstrates the technical feasibility and safety of 90Y-RE in dogs, while preliminary, initial data on the efficacy of 90Y-RE as a potential treatment for brain cancer is encouraging.

Correction to: Yttrium-90 radioembolization as a possible new treatment for brain cancer: proof of concept and safety analysis in a canine model.

An amendment to this paper has been published and can be accessed via the original article.

Musculoskeletal MRI.

MRI has the unique ability to detect abnormal fluid content, and is therefore unparalleled in its role of detection, diagnosis, prognosis, treatment planning and follow-up evaluation of musculoskeletal disease. MRI in companion animals should be considered in the following circumstances: a definitive diagnosis cannot be made on radiographs; a patient is nonresponsive to medical or surgical therapy; prognostic information is desired; assessing surgical margins and traumatic and/or infectious joint and bone disease; ruling out subtle developmental or early aggressive bone lesions. The MRI features of common disorders affecting the shoulder, elbow, stifle, carpal, and tarsal joints are included in this chapter.

Comparison of conventional spin-echo and fast spin-echo magnetic resonance imaging in the canine brain.

T2-weighted fast spin echo and conventional spin echo are two magnetic resonance (MR) pulse sequences used to image the brain. Given the same scan parameters the resolution of fast spin-echo images will be inferior to that of conventional spin-echo images. However, fast spin-echo images can be acquired in a shorter time allowing scan parameters to be optimized for increased resolution without increasing the time to an unacceptable level. MR imaging of the brain of 54 dogs, suspected of having parenchymal brain abnormalities was performed using a 1.5 T scanner. Acquisition time ranged from 4 min 24 s to 7 min 16 s (average = 5 min 15 s) for fast spin-echo scans and from 6 min 32 s to 11 min 26s (average = 7 min 55s) for conventional spin-echo scans. All reviewers consistently rated the resolution of fast spin-echo images higher than the conventional spin-echo images (P = 0.000). The potential disadvantages of fast spin-echo acquisitions (motion artifacts, blurring, and increased hyperintensity of fat) did not affect the resolution of the images. Fast spin echo offers increased resolution in a comparable time to conventional spin echo by increased number of excitations and finer matrix size, thus improving the signal-to-noise ratio and spatial resolution, respectively.