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Summary

Proportional hospital accession ratios for equine ocular/adnexal squamous cell carcinoma (scc) were determined for 14 colleges of veterinary medicine participating in the Veterinary Medical Data Program between January 1978 and December 1986. Comparison of the ratios with their respective geographical, physical data has shown an increased prevalence of scc with an increase in longitude, altitude, or mean annual solar radiation. In contrast, prevalence of scc increased with a decrease in latitude.

Between January 1978 and December 1988, 147 horses with ocular/adnexal scc were admitted to the Colorado State University Veterinary Teaching Hospital. Diagnosis was confirmed by histologic examination of appropriate tissue specimens. Medical records provided information regarding month and year of admission and diagnosis, age at diagnosis, breed, gender, and hair color. Comparison with a randomly selected hospital control population revealed an increased prevalence of ocular/adnexal scc with an increase in age (P < 0.001). Compared with Quarter Horses, draft breeds (Belgian, Clydesdale, and Shire) and Appaloosas had a significantly (P < 0.001) greater prevalence of ocular/adnexal scc. Sexually intact males and females were significantly (P < 0.001) less likely (5 and 2 times, respectively) to have ocular/adnexal scc when compared with castrated males. The prevalence of ocular/adnexal scc was significantly greater for all hair colors when compared with bay, brown, or black (P < 0.01).

Free access
in Journal of the American Veterinary Medical Association

Summary

Between January 1978 and December 1988, 147 horses with ocular/adnexal squamous cell carcinoma (scc) were admitted to the Colorado State University Veterinary Teaching Hospital (CSU-VTH). Diagnosis was conjirmed by histologic examination of appropriate tissue specimens. Medical records and communication with owners, referring veterinarians, or both provided information regarding initial examination, treatment at the CSU-VTH, and final outcome. At initial examination, 123 (83.7%) horses had unilateral involvement and 24 (16.3%) horses had bilateral involvement. The nictitating membrane, nasal canthus, or both (28.1%); limbus (27.5%); and eyelid (22.8%) were most commonly affected. In addition to the ocular/adnexal location, scc was found elsewhere in 14 (9.5%) horses at initial examination. Adequate follow-up (≥ 4 months) for examination of tumor recurrence and survival analysis was obtained for 125 (85.0%) cases. After treatment at the CSU-VTH, tumor recurred in 30.4% of the cases. Tumor location, multiple vs single tumors at initial diagnosis, and CSU-VTH treatment modality influenced the recurrence of tumors. Survival analysis revealed a good prognosis for horses with ocular/adnexal scc. Although undefined, a conservative estimate of the median survival time was 47 months. Six factors (treatment prior to referral, tumor location, tumor size, single or multiple tumors, treatment modality at the CSU-VTH, and recurrence or nonrecurrence) were analyzed to determine their relation with survival. Treatment prior to referral, multiple vs single tumors at initial examination, and treatment modality used at the CSU-VTH did not influence survival. Tumor location influenced survival; scc involving the eyelid or orbit was associated with the poorest prognosis. Tumor stage (maximal dimension) was inversely related with survival. One or more recurrences of scc markedly reduced the likelihood of survival.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate, for clinically normal dogs, results of Schirmer tear tests in eyes without topical anesthetic (STT) and to detect differences associated with breed, sex, age, day, and time of day in eyes in which STT was performed after use of topical anesthetic (STTa).

Animals—41 Beagles, 43 Labrador Retrievers, 25 Golden Retrievers, 26 English Springer Spaniels, and 22 Shetland Sheepdogs.

Procedure—Beagles had STT and STTa values measured twice daily for 5 days. Client-owned dogs of 4 other breeds had STT and STTa values measured once.

Results—Mean ± SD values of Beagles for STT and STTa were 20.2 ± 2.5 and 3.8 ± 2.7 mm/min. Mean values for STT and STTa were as follows: Labrador Retriever, 22.9 ± 4.1 and 9.6 ± 3.8 mm/min; English Springer Spaniel; 20.7 ± 3.2 and 5.4 ± 3.4 mm/min; Golden Retriever, 21.8 ± 3.7 and 8.8 ± 3.1 mm/min; and Shetland Sheepdog, 15.8 ± 1.8 and 3.6 ± 2.8 mm/min. Overall mean values for STT and STTa were 20.2 ± 3.0 and 6.2 ± 3.1 mm/min. Differences for STT and STTa were detected among breeds, but significant differences were not associated with sex or age within each breed or in overall values for all dogs.

Conclusions and Clinical Relevance—Results for the STT reported here compare favorably with reported values, except for results of Shetland Sheepdogs; however, results for the STTa differ dramatically from reported values. Clinicians should consider effects attributable to breed when evaluating results of STT and STTa in dogs. (Am J Vet Res 2000; 61:1422–1425)

Full access
in American Journal of Veterinary Research

Summary

Eye enucleations performed on 109 dogs, 29 horses, and 23 cats involved placement, of 136 silicone orbital implants and 7 mesh implants. Mean follow-up times were 2.4 years (range, 3 weeks to 9 years) in dogs, 3.4 years (range, 10 days to 10.5 years) in horses, and 1.5 years (range, 3 weeks to 7.5 years) in cats. Implants failed in 1 of 96 dogs (1.04%), 3 of 29 horses (10.3%), and 3 of 18 cats (16.7%). Implant failure was attributable to various causes in all species; however, cats appeared to be more prone to late extrusion than were dogs and horses. Implantation of an orbital prosthesis was a safe and inexpensive method for improving cosmetic appearance after enucleation in dogs, horses, and cats.

Free access
in Journal of the American Veterinary Medical Association

Summary

Eighteen prolapses of the gland of the third eyelid in 17 Beagles were randomly allocated to 3 groups, which included nontreated (group 1, n = 6), excised (group 2, n = 4), and surgically repositioned (group 3, n = 8) glands. A Schirmer tear test (STT) was performed on affected and normal (control) eyes for 5 consecutive days on weeks 0 (baseline), 2, 4, 6, 8, 10, 12, 16, 18, 20, and 24. All prolapsed third eyelid glands were excised and examined histologically.

Ten female and 7 male Beagles were used in the prospective study. Mean age at prolapse was 35.1 weeks (range, 6 to 89 weeks). Control STT data revealed a population mean of 22.2 ± 2.1 mm/min. Complications developed in 4 of 6 eyes when the gland was allowed to remain in a prolapsed position. Complications for group-1 eyes were significantly (P < 0.005) greater than those for eyes in groups 2 and 3 (0 of 12). Comparison of affected and control eye baseline data revealed decreased STT values for eyes with prolapsed glands (P < 0.01). Mean differences between affected and control eyes were 2.2, 2.0, and 3.4 mm/min for groups 1, 2, and 3, respectively. A significant (P < 0.001) decrease in lacrimation (0.2 to 3.1 mm/min) in group-2 eyes was detected after removal of the gland. Tear production for affected eyes of nontreated dogs fluctuated above and below that of control eyes prior to excision of the prolapsed gland of the third eyelid; however, with time, affected and control eye STT values were not significantly different. Despite an increase in lacrimation after treatment of group-3 eyes, comparison of affected and control eye STT values revealed a persistent decrease in lacrimation (0 to 2.2 mm/min); however, reduction of lacrimation after surgical repositioning was less than that which resulted if the prolapsed gland of the third eyelid was excised (P < 0.02). Histologic changes in the gland of the third eyelid were mild, and significant differences were not detected among the 3 groups.

Free access
in Journal of the American Veterinary Medical Association

Objective

To compare iridocorneal angle grading systems on the basis of gonioscopy and ultrasound biomicroscopy (UBM).

Design

Original cross-sectional observational study.

Animals

22 dogs.

Procedure

Gonioscopy, goniophotography, and UBM were performed on 38 eyes from dogs without clinical evidence of glaucoma in the eyes examined.

Results

Predominant gonioscopic grades derived from goniophotographs were considered normal (n = 26) and mild (12). Ultrasound biomicroscopy angle measurements ranged from 16 to 38° (mean ± SD, 26.2 ± 4.5°). Ciliary clefts depicted on UBM images were graded as open (n = 4), compact/narrow (23), and closed (11). Significant differences were not found between UBM-derived ciliary cleft grades and goniophotography-derived dysgenesis grades, nor between UBM-derived ciliary cleft grades and subjective gonioscopic grades.

Clinical Implications

Because gonioscopy allows evaluation of the anterior face of the ciliary cleft, whereas UBM provides cross-sectional information of the iridocorneal filtration angle, UBM may yield more information regarding pathogenesis and prognosis of, and preferred management approaches to, glaucoma. Ultrasound biomicroscopy may also be useful as a predictor of glaucoma or to diagnose early stages of glaucoma. (J Am Vet Med Assoc 1998;213:635-638)

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine effects of intraincisional bioactive glass on healing of sutured skin wounds in dogs.

Animals—9 purpose-bred mature female Beagles.

Procedure—3 small matched bilateral (treated vs control) full-thickness truncal skin incisions were made and sutured. Treated wounds received intraincisional particulate bioactive glass prior to closure. Laser Doppler perfusion imaging was used to assess percentage change in tissue perfusion 3 and 5 days after incision on 1 set of 2 matched wounds, and skin and subcutaneous tissue-cutaneous trunci breaking strength were assessed at 5 days. The other 2 sets of wounds were used for histologic evaluation at 5 and 21 days, respectively.

Results—Subjective signs of gross inflammatory reaction were not detected in treated or control wounds. At 5 days, median subcutaneous tissuecutaneous trunci breaking strength was significantly higher in treated wounds than in control wounds (188.75 vs 75.00 g). At 5 days, median scores were significantly higher for neutrophils (1 vs 0), macrophages (2 vs 1), and necrosis (1 vs 0) for treated wounds than for control wounds. At 21 days, median macrophage scores were significantly higher for treated wounds than for control wounds (2 vs1).

Conclusions and Clinical Relevance—Bioactive glass in soft tissues does not cause a gross inflammatory reaction but causes an increase in histologic signs of inflammation, which decreases with time. Bioactive glass has potential for increasing tissue strength. Increased subcutaneous breaking strength could be beneficial in treating wounds in which early healing strength is needed. (Am J Vet Res 2001;62:1149–1153)

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE To measure incidence and estimate temporal and spatial dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) infection in US sow herds.

ANIMALS 371 sow herds in the United States from 14 production companies.

PROCEDURES The exponentially weighted moving average was used to monitor incident PRRSV infections for onset of an epidemic. The spatial scan statistic was used to identify areas at significantly high risk of PRRS epidemics. A χ2 test was used to estimate whether there were significant differences in the quarterly and annual PRRS incidence among time periods, and a bivariable logistic regression model was used to estimate whether PRRSV infection during a given year increased the odds of that herd being infected in the following year.

RESULTS During the 4-year period of this study, 29% (91/319; 2009 to 2010), 33% (106/325; 2010 to 2011), 38% (135/355; 2011 to 2012), and 32% (117/371; 2012 to 2013) of the herds reported new infections. Weekly incidence was low during spring and summer and high during fall and winter. The exponentially weighted moving average signaled the onset of a PRRSV epidemic during the middle 2 weeks of October each year. Disease incidence was spatially clustered. Infection in the previous year increased the odds of infection in 2010 to 2011 and 2011 to 2012.

CONCLUSIONS AND CLINICAL RELEVANCE Results indicated a striking repeatability in annual PRRSV temporal and spatial patterns across 4 years of data among herds from 14 production companies, which suggested that efforts to control PRRSV at a regional level should continue to be supported.

Full access
in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Summary

After removal of 1 metatarsal pad and formation of a granulation tissue bed, free segmental 6- × 8-mm grafts from digital pads were sutured into recessed same-size recipient sites in the granulation tissue. In 5 dogs, the grafted area had been denervated by excision of a segment of the tibial nerve at the level of the tarsus. The grafted area was not denervated in the remaining 5 dogs. In both groups of dogs, the grafts placed around the periphery of the wound healed, blocked ingrowth of delicate epithelium from the surrounding skin, and provided a tough keratinized epithelium that covered the wound's center. As healing progressed, the grafts coalesced as the wounds contracted. Weight bearing resulted in graft expansion to provide functional weight-bearing tissue.

Dogs of the denervated group had clinical and histologic evidence of collateral sensory reinnervation of the denervated area. However, with the exception of 1 dog, results of sensory nerve action potential tests indicated that reinnervation may not have been by way of regeneration across the excisional gap in the nerve.

Evaluation of reinnervation of the tibial autonomous zone in 2 additional dogs revealed clinical evidence that collateral reinnervation began between 19 and 28 days after nerve excision and progressed proximad to distad. Results of sensory nerve action potential tests indicated that reinnervation may not have been via regeneration across the excision site. Results of fluorescent tracer studies did not have positive findings regarding the route of collateral reinnervation.

Segmental paw pad grafts can be used effectively to provide weight-bearing tissue on a dog's limb. With local nerve damage on the distal portion of the limb, collateral innervation can grow into the area to reinnervate tissues, including pad grafts.

Free access
in American Journal of Veterinary Research