Medicine & Surgery

Changes in the Pulmonary Circulation of Horses with Exercise-Induced Pulmonary Hemorrhage.

Exercise-induced pulmonary hemorrhage is a very common problem in race horses, but little is known about the diagnosis and treatment of the condition. Currently, it is thought that pulmonary blood vessels rupture at very high pressure causing bleeding into the airways. Despite the widespread use of such drugs, as the diuretic furosemide, there is no evidence to support use of such drugs in control of pulmonary bleeding. The project involves evaluation of the sensitivity and specificity of nuclear scintigraphy in the diagnosis of exercise-induced pulmonary hemorrhage. Horses known to be "bleeders", are exercised on the treadmill at racing speed to exhaustion, and their lungs evaluated for changes in blood flow and distribution as a consequence of exercise. The project has evaluated 4 of the anticipated 20 needed to conclude the project.

Sponsor: College of Veterinary Medicine
PIs: Phil Woods and W. Tod Drost

Muscular Dystrophy in the Pembroke Corgi Dog.

Muscular dystrophy (MD) is one of the most common inherited diseases of man, with 1 in 4000 male births being affected. The classic Duchenne muscular dystrophy appears to be due to a mutation in the dystrophin gene, causing breakdown of muscle cells and consequent muscle weakness. We are developing a model of the human condition in the dog, with the long term goal of developing methods to treat and manage the condition in humans. From an initial male dog affected with MD, we have produced 10 females that carry the mutant gene. The carrier females are now being bred to produce affected offspring. At the cellular and molecular level the condition is similar to the Duchenne form of MD, with lack of cellular expression of dystrophin. Molecular analysis of DNA from the affected dog DNA shows the mutation in the Corgi dog to be different from that of MD in the Golden Retriever dog.

Sponsor: College of Veterinary Medicine
PIs: Phil Woods; Jerry Malayer and Gayman Helman (CVM); Farhat Husain (OU College of Medicine)

Investigation of Orbifloxacin in the Treatment of Experimental Canine Cystitis

Objectives:

To investigate the feasibility of inducing cystitis with salicylic acid, ethanol, and dual bacterial infections with Proteus mirabilis and Pseudomonas aeruginosa.
To evaluate the efficacy of orbifloxacin in treatment of cystitis as induced above.

Progress Report:

As stated in the 1995 report, the pilot study to establish dual infection was not successful.

The study to evaluate efficacy of orbifloxacin against p mirabilis was completed in October, 1995, and the report submitted to Schering Plough early in 1996. Per the agreement with Schering Plough, results are confidential at this stage. A manuscript on the attempt to induce dual infection is still in preparation. Dr. Bowles presented research findings at the Research session, American College of Veterinary Internal Medicine Scientific Forum in May, 1997.

Sponsor: Schering Plough Animal Health, Union, New Jersey
PIs: G. Turnwald, M. Bowles, R. Welsh, and J. Hoffman; T. Katz (Schering-Plough)

Efficacy of Acupuncture for the Treatment of Navicular Syndrome

This is an ongoing project which involves the use of acupuncture therapy for treatment of navicular syndrome in horses. Improvement in lameness is evaluated after a three-course therapy. Experimental subjects consist of client horses which have been diagnosed with navicular syndrome. Approximately 12 horses have been evaluated to-date.

Sponsor: Grady Young
PI: Henry Jann

Effects of Growth Factors on Fibroblast Migration In Vitro

Several growth factors will be evaluated for their effect on tendon derived fibroblasts in vitro. Specific parameters to be evaluated include migration rate and total cell numbers which migrate on a piece of suture material placed through a segment of tendon explant. Experimental trials will be completed by June 23, 1997.

Sponsor: Davis & Geck
PI: Henry Jann

Efficacy of IM PSGAG in the Treatment of Equine Navicular Syndrome: A Clinical Field Trial

This study investigates the efficacy of intramuscular PSGAG (Adequan) in the treatment of equine navicular syndrome. The effects of this drug on clinical lameness and metabolic activity associated with the navicular bone and surrounding soft tissue will be evaluated over a three-month period. The hypothesis is that intramuscular Adequan will be useful therapy to treat horses with navicular disease. Positive response to the drug will be reflected by improved lameness scores and normalized metabolic activity in the region of the navicular bone as evaluated by nuclear scintigraphy. Clinical relevance is for its use as a treatment of navicular syndrome, a very common, debilitating lameness.

Sponsor: Luitpold Pharmaceuticals, Inc.
PIs: Michael Collier, Olin Balch and Tanya Ciacciarelli

Effects of Intra-osseous Implantation on the Physical Properties of a Bio-Absorbable Spherical Suture Anchor: an Animal Study

The purpose of this study is to examine effects of intraosseous implantation on the physical properties of a Bio-Absorbable spherical suture anchor at various time intervals. The reaction of adjacent tissue to the implant and the healing of the overlying tissue to bone will also be evaluated. The hypothesis is that the biosphere implanted into bone will retain its physical properties for a period of time that exceeds the biological healing of the overlying soft tissue to bone at the implantation site. Clinical relevance is for its use as a biodegradable soft tissue fixation device in orthopaedics, specifically in the reattachment of the shoulder joint rotator cuff tendons.

Sponsor: L. Johnson MD Research Fund
PIs: Michael Collier, Tanya Ciacciarelli, Olin Balch, Lanny Johnson, Larry DeBault, James Bullen, and Henjen Ho

Energy Absorption Capacity of the SMB II Sports Medicine Boot

The efficacy of commercially available equine support boots will be tested by using a universal testing machine to flex and extend bandaged equine cadaver hindlimbs. The original prototype, two subsequent generations of improvements of an equine support boot, and a fourth condition consisting of the most recent version of the equine support boot that had been additionally used by application to the limbs of horses engaged in athletic activities will be tested. The hypothesis is that equine cadaver limbs, bandaged by currently available commercial equine support boots, will require significantly greater force (therefore absorb greater energy) to deflect the leg a constant distance, compared to a non-bandaged limb. Clinical relevance is for the use of biomechanically effective equine support boots to prevent fetlock hyperextension in performance horses. Injuries to the suspensory apparatus of the fetlock associated with fetlock hyperextension are a common cause of debilitating lameness.

Sponsor: Professional's Choice Sports Medicine Products, Inc.
PIs: Olin Balch, Michael Collier, and Jerry Brucewitz

In Vitro Biostimulation of Chondrocytes Using the Ho:YAG Laser and Growth Hormone

Metabolic activities of established cell lines of equine chondrocytes and human chondrosarcoma will be studied following exposure to sub-ablative levels of Ho:YAG energy and/or growth hormone. Cell production of collagen, proteoglycan, and Na-hyaluronate will be quantitated. Quantitation of exopeptidase activity will also determined. Clinical relevance of this research is in articular cartilage regeneration and the treatment of degenerative arthritis.

Sponsor: L. Johnson MD Research Fund
PIs: Michael Collier, Olin Balch, Lanny Johnson, and Larry DeBault

Small Fiberscope Design, Surgical Use, and Image Processing via Digital Capture and Tele-linking for Surgical Intra-operative Consultation

Surgical application and use of small submillimeter fiberscope designs and image processing hardware/software for visualization in small cavities, vascular tree and transmission of surgical images across the Internet and dial-up ISDN will be studied.

Sponsor: Smith & Nephew Endoscopy, Inc. and Hays Biggs Endowment Fund
PIs: Michael Collier and Olin Balch

Long-Term Effects of Holmium YAG Laser Radiation on Cartilage Metabolism, Healing, and Biochemical Properties of Repaired Tissue and Subchondral Bone Healing in a Weight Bearing Chronic Lesion Model

Recent research studies utilizing Ho:YAG laser energy have shown promising results in providing an appropriate stimulus for cartilage repair processes with chondral proliferation and reduction of tissue reaction. Objectives of this research study are to 1) histologically compare perilesional cartilage, lesional repair tissue, and subchondral bone healing in control and treated groups following treatment of chronic full-thickness cartilage lesions and perilesional cartilage with a selected level of Ho:YAG laser energy and six months of continuous active weight bearing; and 2) to perform biochemical evaluation of lesional reparative tissue and perilesional cartilage, examining for upregulation of repair tissue following exposure to laser energy. This study will determine if the integrity and biochemical properties of repaired tissue can be improved by treatment with selected levels of laser energy and if cartilage metabolism can be upregulated and reparative tissue stimulated.

Sponsors: Lanny Johnson, MD, Research Fund; Doris Stein Foundation; Beckman Laser Institute; and Coherent Medical Corporation
PIs: Michael Collier, Olin Balch, Lanny Johnson, and Larry DeBault

Legg Perthes Disease

This study utilized the equine humoral epiphysis as surgical model. A large defect was created in the equine proximal humoral epiphysis and received an autogenous bone graft into the iatrogenically created surgical lesion to simulate the clinical presentation of Legg Perthes disease. Radionuclear imaging and histology, including appropriately placed bone markers, were used to quantitative the reparative process in this pilot model. Successful completion will lead to development of a larger, long term project to document the effectiveness of this newly designed surgical technique.

Sponsor: Lanny Johnson, MD, Research Fund
PIs: Michael Collier, Olin Balch, Lanny Johnson, and Larry DeBault

Effects of Autogenous Chondral Graft in Glycolic/Lactic Acid Copolymer Base and Blood Clot Adherence on Equine Articular Cartilage Defects

This study was designed to determine the effects of autogenous chondral graft in glycolic/lactic acid copolymer base and blood clot adherence on equine articular cartilage defects. Recent studies revealed that laser energy stimulated chondral proliferation in cartilage repair in vitro and in vivo. Defined energy levels consistently upregulated cartilage proteoglycan, collagen, non-collagen protein and DNA synthesis in the absence of histologic or biochemical evidence of enhanced matrix catabolism. Other studies have shown that blood clot adherence at the surgical site is equally imperative to initiate fibrocartilaginous and/or hyaline-like cartilage repair. We evaluated blood clot adherence in conjunction with autogenous chondral graft tissue in a glycolic/lactic acid copolymer base applied at the surgical site.

Sponsor: Lanny Johnson, MD, Research Fund
PIs: Michael Collier, Olin Balch, Lanny Johnson, and Larry DeBault

Use of Force Sensing Array Technology In the Development of a New Equine Saddle Pad: Static and Dynamic Evaluations and Technical Considerations

Scientific approaches to the classical art of saddle-pad fitting with the horse has become available during the past few years. Force Sensing Array (FSA) technology has offered clinicians in the medical profession innovative systems for rehabilitation applications. With proven usefulness in the medical sector, the application of Force Sensing Array (FSA) technology in pressure mapping of the equine back and saddle has potential clinical and research applications in veterinary medicine. The objectives in this study are to apply FSA technology in evaluation of an equine athletic saddle pad and pad liners and to document any observed/potential areas of error within the system that would affect objectivity in data collection/interpretation. All dynamic scans demonstrated a repeatable pattern of pressure distribution that were associated with gait, load distribution and horse limb placement. The in-motion scans gave the best overall evaluation of effectiveness of the pad liners studied. This study did not define "normal" static or dynamic saddle-pad-horse pressure gradients or patterns. Potential exists for animal and operator induced error when using this technology. The pressure distribution pattern is the most valuable data to be gained from Force Sensing Arrays and should be the primary use of the device. Precise scientific methodology must be used in these type of studies.

Sponsors: Professional's Choice Sports Medicine, Inc.
PIs: Michael Collier, Olin Balch, and Chris Durham

LACS Procedure Using the Ho:YAG Laser in a Canine Model: Intraarticular Pressure and Histological Observations

Recently, a new surgical procedure has been developed for the treatment of glenohumeral instability (GHI) called Laser-Assisted-Capsular-Shift (LACS). Laser-Assisted-Capsular-Shift procedures are performed via arthroscopic visualization using Holmium:YAG laser energy application to GH joint capsular and ligamentous tissues. Laser energy is applied until gross contraction or "shrinkage" of the capsular tissue is observed. A previous clinical retrospective study in humans including 41 procedures reported 93% excellent/good results at 6 months follow-up (Thabit). Controversy exists regarding the safety and efficacy of LACS. To date, no long term in vivo animal model studies have been undertaken to evaluate morphologic or biochemical alterations to glenohumeral capsular tissues following exposure to Ho:YAG laser energy. Our hypothesis was that Ho:YAG laser energy capsuloplasty (LACS) of the greyhound GH joint would have an effect on intraarticular pressure (IAP) and volume and show histologic evidence of capsular tissue shrinkage and laser-induced temperature denaturation and reanealment of collagen without undesirable tissue reaction. The objectives were to study the effects of Ho:YAG laser energy on the structural state of the canine GH joint capsular tissue using gross, histological and static and dynamic IAP analysis. Additionally, this study was undertaken to determine if this procedure could be an in vivo animal model for the study of LACS in man.

Sponsors: Lanny Johnson, M.D. Research Fund
PIs: Michael Collier, Olin Balch, Lanny Johnson, and Larry DeBault

Technical Considerations For Acquisition, Analysis and Archiving Static and Dynamic Intraarticular Pressure Measurements for Laser Surgery Studies

Accurate measurement of intraarticular pressure (IAP) in static and dynamic studies is important in the evaluation of compartmentation of fluid within the joint and in the evaluation of other physiologic mechanisms affected by changes in intraarticular (i.a.) fluid pressure. Previous studies have evaluated various pressure measurement techniques in the evaluation of intracompartmental and IAP. These measurement systems rely on hydrostatic pressure transmission along a fluid column and have been shown to exhibit variability in pressure artifact and maintaining calibration. Additionally these systems have a slow frequency response which is undesirable in dynamic studies.

The Camino® catheter has been shown to allow accurate, high frequency response recording of IAP during CPM. However, additional design and instrumentation development are required to ensure a closed system during catheter insertion for accurate initial recording of subatmospheric pressures within some synovial joints and in digital data acquisition and analysis of IAP obtained during CPM studies. Our hypothesis was that an instrumentation system consisting of a pressure transducer-tipped catheter system, graphical digital programming system, digital image capturing system and specially designed computer would allow highly accurate scientific data acquisition and analysis for a wide variety of P/V, i.a. compliance and i.a. surgical laser studies. The objectives were to collect and analyze data from static and dynamic (CPM) measurements of i.a. pressures in horses and dogs for repeatability and accuracy in data acquisition and management that could be used as baseline data in laser surgery P/V studies in those animal models and man.

Sponsors: Equine Surgery/Sports Medicine Chair Endowment Fund
PIs: Michael Collier, Olin Balch, Lanny Johnson, A.J. Pedowitz, and Chris Durham

Dynamic Normal Intraarticular Pressures and Compliance During C.P.M. in Equine Joints

Data acquisition from research and clinical cases during C.P.M. after distension using various dynamic intra-articular surgical infusion systems is being collected to establish normals as the basis for joint pressure/volume and compliance studies. Additionally, flow dynamics of these various i.a. infusion systems is being studied during use in arthroscopic surgical procedures.

Sponsors: Equine Surgery/Sports Medicine Chair Endowment Fund, Smith & Nephews Endoscopy, Inc.
PIs: Michael Collier, Olin Balch, Lanny Johnson, A.J. Pedowitz, and Chris Durham

Development of a Reliable Bovine In Vitro Embryo Production System.

The primary objective of this investigation is to develop a reliable method of producing cattle embryos using in vitro technologies. This will facilitate salvaging potentially valuable genetic material from superior cows no longer able to conceive. In addition, IVF technology can be used to enhance genetic gain as the generation interval can be significantly reduced by developing embryos from young heifers prior to puberty. Finally, a reliable system will allow for future investigations into the many facets of in vitro embryo production so that improvements in the overall efficiency of the technique may be greatly improved.

Sponsor: College of Veterinary Medicine
PI: Gregor Morgan and Tulio Prado

Laser-Induced Shock Wave Lithotripsy of Canine Urocystoliths and Nephroliths.

The purpose of this study is to investigate the utility of a flashlamp-pumped pulsed Cr:Tm:Ho:YAG laser in the fragmentation of canine urocystoliths and nephroliths. This innovative technique of laser lithotripsy involves the transformation of light energy into acoustical energy that generates a shock wave sufficient to fragment calculi (photoacoustic ablation). The Ho:YAG laser will be transmitted to the calculi via quartz endoscopes resulting in effective fragmentation with little surrounding tissue damage.

Sponsor: Morris Animal Foundation Research Advisory Council
PI: J. Paul Woods

Prospective Study of Progeny of Inapparent Equine Carriers of Equine Infectious Anemia in a Herd of Wild Indian Horses in Southeast Oklahoma.

Equine infectious anemia (EIA) is a retro virus that causes anemia, thrombocytopenia, fever, and depression in clinically affected horses. Since the 1970's, federal and state regulations have required euthanasia or permanent quarantine of animals which have tested positive for EIA-V in an effort to control this disease. It is our hypothesis that clinically inapparent carriers of EIA-V pose minimal risk of causing infection in offspring if animals are allowed to carry on normal reproductive activities (pregnancy, parturition, foaling, neonatal/foal activities, weaning).

A herd of 32 EIA-V infected Choctaw Indian Horses and their respective offspring will be bled at 30-day intervals to determine specific EIA-V immunogenicity and infectivity. Serum and plasma will be measured for EIA viral antibody (AGID & CELISA - p26 core protein; immunoblot - gp 45 & gp 90 envelope proteins) and viral RNA (polymerase chain reaction - PCR). Risk factor analysis associated with pregnancy, parturition, and foaling activities will be determined in foals which become permanently infected with the EIA virus. Foals determined to be uninfected after 60 days of quarantine will be relocated to an EIA free location in an effort to preserve the herd bloodlines and to reach negative EIA status. Positive animals will remain in permanent quarantine until natural attrition is complete.

Sponsor: College of Veterinary Medicine
PI: Rebecca S. McConnico

Sonographic Determination of Hepatic Echogenicity in Normal Cats Using Computer-Aided Image Analysis

Hepatic lipidosis, an abnormal accumulation of fatty tissue within the liver, is a common ailment of cats. Sonography is a non-invasive method of detecting hepatic lipidosis that depends on the subjective opinion of the sonographer. Using computer-aided image analysis, numerical values correlating to the echogenicity and echotexture of the liver and adjacent tissues can be determined. The goal of this project is to objectively determine the echogenicity of a normal feline liver using computer-aided image analysis. Once a numerical value for a normal liver is determined, this method will be applied to abnormal livers to facilitate earlier detection of hepatic lipidosis.

Sponsor: College of Veterinary Medicine Research Advisory Committee
PIs: Wm. Tod Drost, W. Nick Street, George A. Henry, Jim H. Meinkoth, J. Paul Woods

Comparison of 99mTc-DTPA and 99mTc-MAG3 for the Evaluation of Renal Function After Percutaneous Renal Biopsy in Healthy Cats

Percutaneous renal biopsies are used to make a specific diagnosis in cats with renal disease. Nephrons are damaged in the process of obtaining this kidney sample and this may affect the glomerular filtration rate (GFR) and/or the effective renal blood flow (ERBF) the kidneys. Scintigraphy, using 99mTc-DTPA to measure GFR and 99mTc-MAG3 to measure ERBF, is a non-invasive way to measure renal function. The goal of this project is to determine the effects of a percutaneous renal biopsy on GFR and ERBF and to determine how long these changes may last.

Sponsor: College of Veterinary Medicine
PIs: Wm. Tod Drost, George A. Henry, J. Paul Woods, Jim H. Meinkoth

Computer-based Fuzzy Monitoring of Infusion Anesthesia

This project is designed to develop a multivariable, computer-based fuzzy logic monitoring system to adaptively infer depth of intravenous infusion anesthesia. Fuzzy logic reasoning, a powerful new form of information processing, is being employed to infer depth of anesthesia from on-line measurements of cerebral activity (electroencephalogram - EEG) and cardiovascular function (heart rate, blood pressure) in a dog undergoing propofol infusion anesthesia. The goal is to develop a system that will assist clinical anesthesiologists in the delivery of safe, reliable infusion anesthesia. Additionally, the techniques widespread application of fuzzy logic reasoning for biomedical monitoring and control. This project is strengthened by being a collaborative effort on the part of clinical anesthesiologists, chemical engineers, and pharmacologists.

Sponsor: National Institutes of Health and National Library of Medicine
PIs: Ron E. Mandsager and Cyril R. Clarke; James R. Whiteley (CEAT)

Photodynamic Therapy and Photothermal Coagulation for Selective Treatment of Cancer and other Pathologic Conditions

This project encompasses the use of laser energy for photothermal and photochemical (photodynamic therapy) treatment of tumors and other conditions such prolapse of intervertebral discs. It is a collaborative effort involving physicists, physicians, and veterinarians to study new and novel treatments of conditions in both humans and animals. The ultimate goal is establishment of clinical laser programs at both OSU and OUHSC using established techniques and protocols.

Sponsor: Presbyterian Health Foundation
PIs: Kenneth E. Bartels, Mark Rochat, W. Paul Woods, John Hoover, and James Wicksted (OSU); John R. Houck (OUHSC).

College of Veterinary Medicine Sarkeys Surgical Laser Laboratory

Since the establishment of the Surgical Laser Laboratory within the College of Veterinary Medicine, research to establish protocols for clinical applications in veterinary medicine has been a primary objective. In addition, the use of laboratory models has resulted in transfer of technology to both industry and human medicine. Work will continue concentrating on the clinical applications of biomedical lasers coupled with collaborative research protocols involving basic scientists and clinicians.

Sponsor: Sarkeys Foundation
PI: Kenneth E. Bartels

Veterinary Models in the Development of Laser Biomedical Applications for Combat Casualty Care

A collaborative project involving investigators from OSU, University of California (Davis), University of Missouri, and the Beckman Laser Institute will explore mechanisms to develop a method of employing light energy for localized sepsis control in traumatic wounds. Phase 1 will determine, in vitro, if the chromophores indocyanine green, fluorescein, and carbon black can be used to enhance selective targeting of bacteria for photothermolysis. Phase 2 will determine on an in vivo basis if a dye chromophore and specific wavelength of laser light can be used for the selective thermolysis of bacteria without extensive collateral soft tissue injury.

Sponsor: Office of Naval Research
PIs: Kenneth E. Bartels and Rebecca Morton

Ablation of Intervertebral Discs in the Dog Using a Microjet Assisted Dye-enhanced Injection Device Coupled with a Diode Laser

An intervertebral disc model in the dog was recently developed for clinical and basic research applications. Using this model, a project investigating the use of a diode laser and the chromophore indocyanine green as an energy enhancer has been initiated. Advantages of this approach and potential future applications for diode laser technology will be determined using neurologic and clinical examinations, radiographic evaluation, and histopathologic assessment.

Sponsor: National Institutes of Health through Microfab Technologies, Plano, TX
PIs: Kenneth E. Bartels, George Henry, Wm. Tod Drost, Robert Bahr, and E.L. Stair