Quantification of Urine Elimination Behaviors in Cats with a Video Recording System.

BACKGROUND: Urinary disorders in cats often require subjective caregiver quantification of clinical signs to establish a diagnosis and monitor therapeutic outcomes. OBJECTIVE: To investigate use of a video recording system (VRS) to better assess and quantify urination behaviors in cats. ANIMALS: Eleven healthy cats and 8 cats with disorders potentially associated with abnormal urination patterns. METHODS: Prospective study design. Litter box urination behaviors were quantified with a VRS for 14 days and compared to daily caregiver observations. Video recordings were analyzed by a behavior analysis software program. RESULTS: The mean number of urinations per day detected by VRS (2.5 ± 0.7) was significantly higher compared with caregiver observations (0.6 ± 0.6; P < .0001). Five cats were never observed in the litter box by their caregivers. The mean number of urinations per day detected by VRS was significantly higher for abnormal cats (2.9 ± 0.7) compared with healthy cats (2.1 ± 0.7; P = .02); there were no apparent differences in frequency between these groups reported by caregivers (0.7 ± 1.0 and 0.5 ± 1.0, respectively). There were no differences in mean urination time between healthy and abnormal cats as determined by VRS or caregivers. Mean cover-up time determined by VRS was significantly longer in healthy cats (22.7 ± 12.9 seconds/urination) compared with abnormal cats (8.7 ± 12.9 seconds/urination; P = .03); differences in cover-up time were not detected by caregivers. CONCLUSIONS AND CLINICAL IMPORTANCE: Caregivers commonly underestimate urination frequency in cats when compared to video-based observations. Video recording appears to facilitate objective assessment of urination behaviors and could be of value in future clinical studies of urinary disorders in cats.

Evaluation of a predictive model for implant surface topography effects on early osseointegration in the rat tibia model.

STATEMENT OF PROBLEM: Alterations in commercially pure titanium (cp Ti) implant surface topography can be made to increase bone formation or the interfacial shear strength of bone at the functioning implant. It is not known whether these 2 goals are congruent or mutually exclusive. PURPOSE: The aim of this study was to determine the effect of implant surface topography parameters of calculated biomechanical significance on the process of bone formation in a rat tibia model of osseointegration. MATERIAL AND METHODS: Implants (cp Ti grade IV) were machined and subsequently treated by grit blasting or grit blasting and 6.4 mol/L HCl. Measurements of surface roughness were made by atomic force microscopic analysis of similarly treated titanium disks. Cleaned and sterilized implants (12 machined, 12 with nonideal pit morphology, 12 with ideal pit morphology) were placed into the tibiae of 400-g male Wistar rats by using a series of drills, irrigation, and a self-tapping procedure. After 3 weeks, tibiae were harvested and processed and embedded in methyl methacrylate resin. Polished sections were examined by backscatter electron microscopy, and the percentage implant surface contacting bone was measured with the Scionics PC image analysis program. RESULTS. The implants possessing a proposed ideal pit morphology supported significantly greater bone formation at the implant surface (54% +/- 7% bone-to-implant contact [P<.003]) than the nonideal pit morphology (40% +/- 15%) or machined surfaces (34% +/- 6%). CONCLUSION: Implant surfaces with a proposed ideal pit morphology (which possess a calculated biomechanical significance) enhanced bone formation at early periods after placement in the rat tibia model.