Soft Tissue and Orthopedic Surgery

Photo: Flyer for Colorectal Mass Clinical Trial in Dogs

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Transnare Cryoablation

The clinical trial using transnare cryoablation is no longer ongoing. Because the clinical trial had such a good response and there is continued interest in the procedure, Dr. Steffey has agreed to offer transnare cryoablation as a treatment option through the UC Davis Veterinary Medical Teaching Hospital.  Please review the Transnare Cryoablation: Information for Clients document for additional information.

Below, please find links to all of the clinical trials involving soft tissue or orthopedic surgery. The studies include a multitude of information, including (but not limited to) the study’s purpose, benefits for participating, and financial incentive information. If you have any questions, please contact the individual outlined at the end of each trial summary.

Please visit the Surgery service webpage at the Veterinary Medical Teaching Hospital (VMTH) if you would like to learn more about the amazing things that our surgeons can do for you and your animal.

Cats

Variety of Tumors: Assessing Minimally Invasive Tumor Ablation

Title: Thermal ablation of cancer in dogs and cats

Purpose of Study: The purpose of this study is to evaluate the outcome of treating veterinary patients with minimally invasive tumor ablation technologies including cryoablation and microwave ablation. These methods are growing in the treatment of a variety of cancers in the human medical field, but information in veterinary patients is currently very limited. To date we have completed a study on cryoablation in nasal tumor patients, and this technique has been very successful in reducing tumor volume in nasal tumor patients – although there are no more spots in the formal nasal tumor study, because of this success, we continue to offer this technique as a clinical service to nasal cancer patients, and are expanding the types of cancer that we are evaluating.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey. The coordinators will likely advise you to send your pet's medical records and imaging results for Dr. Steffey's review. If, based on this information, your pet is deemed an appropriate candidate, an appointment will be scheduled.

Participation Requirements: In order to participate in this study, your pet must have **solitary** malignant soft tissue or bony mass **that is deemed amenable to ablation**. Tumor types that MAY be amenable to this treatment include lung tumors, kidney tumors, adrenal tumors, and bone tumors in certain locations. however determination of eligibility is complex and relates to the size of the lesion as well as proximity to/involvement of other important nearby structures. Tumors that are superficial (involving or near to the skin) or that involve the gastrointestinal tract are not amenable to this treatment.

Initial Evaluation for Participation: Evaluation by the V.M.T.H. Small Animal Surgery, Internal Medicine, or Oncology services.

Procedures: If you agree to participate, under general anesthesia, ablation probes will be placed into your pet’s mass under ultrasound guidance and the tumor will be ablated.

Benefits: This treatment method may only be palliative, but it is our hope that in appropriately selected patients, we may improve quality of life as well as longevity.

Owner Responsibilities: The study will cover the cost of the ablation probes and generator. Costs of pre-operative workup, general anesthesia, recommended imaging, hospitalization, and general management of the disease process or any complications that occur during treatment are your responsibility.

Variety of Tumors and Diseases: Improving Operative Detection of Tumors

Title: Fluorescent imaging of cancer

Purpose of Study: Near-infrared fluorescent imaging utilizes special wavelengths of light to identify important structures, and is used in surgery to improve surgical decision making. The fluorescent light is generated by a special contrast agent (a “fluorophore”) that is injected into the patient. When a special light source is used to illuminate the surgical site, any tissue in which this fluorophore is located will glow, aiding the surgeon in identifying the location or extent of disease. Based on early experiments in rodents and human clinical trials, this very sensitive tool has the potential to improve surgical decision-making and improve overall treatment for a wide variety of diseases. The purpose of this study is to evaluate the efficacy of this imaging modality in veterinary patients presenting with naturally occurring neuroendocrine tumors disease processes.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey.

Participation Requirements: Cats with the following conditions are most likely to benefit from this study: hyperparathyroidism, thyroid cancer, pancreatic cancer, adrenal cancer, thymoma, mammary (breast) cancer, lung cancer, anal sac gland cancer, oral cancer, mast cell tumor. Cats with severe kidney or liver disease are not eligible to participate.

Initial Evaluation for Participation: Evaluation by the V.M.T.H. Small Animal Surgery, Internal Medicine, or Oncology services.

Procedures: If you agree to participate, the best fluorophore for your pet’s tumor will be administered or intravenously, at a dose and timing considered to be optimal by your attending veterinarian.

Benefits: It is hoped, but is not known if there will be a specific benefit to your individual pet. Fluorescent imaging may or may not improve operative localization and dissection of your pet’s tumor.

Owner Responsibilities: Costs of standard pre-operative workup, general anesthesia, recommended imaging, hospitalization, and general management of your pet’s disease process or any complications that occur during treatment are your responsibility. The cost of the fluorophore and special imaging is covered by the study. There are no risks associated with the imaging itself, as it only involves light; there is no radiation exposure to the patient. The fluorophores used in this study are FDA-approved for use in humans and have been used without complication in our hospital for the past 18 months. The primary risk of this procedure is associated with injection of these drugs is an allergic reaction, which is very rare, but unpredictable in an individual patient (like any other drug reaction, including antibiotics). If an allergic reaction should occur, immediate costs of treatment (immediate supportive medications, support of blood pressure) will be covered by the study; however, the owner will be responsible for any treatment costs for prolonged or severe complications.

Dogs

NEW! Colorectal Masses: New Minimally-Invasive Approaches to Surgical Planning

Title: Assessment of colorectal masses in dogs

Purpose of Study: Although the prevalence of rectal cancer in dogs is low, it still proves a significant problem for diagnosis and treatment when it occurs. Definitive diagnosis can be challenging at times because current imaging tools have their limitations. The current gold standard imaging method for evaluation of rectal masses by colonoscopy. The purpose of this portion of the study is to evaluate two different novel minimally invasive approaches to pre-operative imaging and surgical planning.

In addition to assessing new diagnostic imaging techniques, the other portion of the study intends to assess two protocols for bowel preparation prior to imaging. Traditional bowel preparation for a colonoscopy procedure (the current usual method of surgical planning for masses of the colon/rectum) requires a full cathartic in-hospital bowel preparation, which can be expensive and requires hospitalization. Both of the new bowel cleansing protocols evaluated in this study will allow for sufficient pre-operative planning to facilitate surgical removal, but will be less expensive, and we hope will be less unpleasant for the patient than standard fully cathartic bowel preparation protocols. Additionally, the less intensive bowel cleanses required for study participation would mean that diagnostic evaluation, imaging and surgery could be performed under the same anesthetic episode, thus decreasing hospitalization time for the patient, and costs to the owner.

Contact: Contact Dr. Jeffrey Mitchell (Small Animal Surgery) via email (jwmitchell@ucdavis.edu) or call (530) 752-1393 to make an appointment.

Participation Requirements: Dogs diagnosed with rectal mass(es) with owners who have elected to proceed with further diagnostic imaging and surgical removal of these masses

Initial Evaluation for Participation: Prospective candidates will require an appointment with and evaluation by the UC Davis VMTH Soft Tissue Surgery, Internal Medicine, Oncology, or Community Practice Services to evaluate their eligibility to participate.

Procedures: If you agree to let your dog participate in this study, the following will happen:

  • After an in-person appointment and consultation with the Soft Tissue Surgery Service to ensure that your dog is a safe candidate to participate in this study, an at-home bowel cleansing protocol will be initiated 2 days prior to the scheduled surgical procedure in which removal of your dog’s rectal mass is planned. The bowel cleansing protocol will involve a special diet for 2 days and may include a special radiographic contrast agent and potentially an orally administered cathartic laxative, depending on which group of the study your dog is enrolled. The allocation of patients to the different bowel preparation study groups is randomized.
  • On the day of the diagnostic imaging, your dog will be anesthetized and then undergo a CT scan one of the imaging procedures. Your dog will then proceed to the operating room where a rigid endoscope will be used to evaluate the mass just prior to surgical removal.
  • If surgery is necessary, your dog will undergo the surgery as determined by the attending Soft Tissue Surgery clinician with your permission.

Benefits: All costs associated with the study, including the bowel preparation protocol medications, CT scan, and rigid endoscopic exam will be paid by the sponsor/department.

Results from this study may lead to improved methods of diagnosis of large bowel disease and/or improved surgical planning for focal large bowel problems.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for:

  • Bringing your dog to any scheduled appointments
  • Covering the standard costs of pre-operative bloodwork, additional diagnostic imaging (chest x-rays, abdominal ultrasound, etc), anesthesia, surgery, and hospitalization for your dog’s disease, as explained by your attending clinician

Printable Flyer (PDF)

Mast Cell Tumors: Assessing Lymph Node Mapping

Title: Sentinel lymph node mapping in dogs with mast cell tumors

Purpose of Study: Mast cell tumors are a very common skin tumor in dogs, and a common mechanism of spread in the body (metastasis) is to nearby lymph nodes. If tumor spread to lymph nodes is identified (as part of staging), this is important information that often influences treatment recommendations. Currently, standard protocols for looking for metastasis in lymph nodes most commonly include aspiration cytology. Aspiration cytology is minimally invasive, but may miss a diagnosis of lymph node metastasis in a concerning number of patients – early literature suggests metastatic disease may be missed by lymph node aspiration in up to 40% of patients! The concern is that not only does aspiration cytology only sample a very small amount of a given lymph node, but that it is difficult to ensure that we have correctly predicted the optimal lymph node to sample for any given mast cell tumor. Lymph node mapping, a technique to visualize the lymphatic drainage of tumors by which tumor cells might spread, is increasingly used to improve cancer staging and treatment protocols in the treatment of cancer in humans. Efforts are made to identify the “sentinel lymph node,” or primary lymph node that is most likely to demonstrate evidence of metastatic disease if it is present. This lymph node can then be surgically removed with the primary tumor, in order to be evaluated microscopically for spread of cancer. However the common method of sentinel lymph node mapping performed in people is not widely available to veterinarians. This trial is being performed to hopefully identify an alternative method of sentinel lymph node mapping that can be more widely accessible to a greater number of veterinary practitioners. By doing so, we hope that this will improve the accuracy of cancer diagnoses and treatment recommendations we make for dogs with mast cell tumors and other cancers, improving their quality of life and lifespan.

Contact:

Participation Requirements: Dogs must have been diagnosed with a peripheral mast cell tumor, have been evaluated by or received a consult from a clinician the Soft Tissue Surgery service to determine if LN mapping is viable for your individual dog, and you have elected surgical excision of this tumor both for diagnostic and treatment purposes.

Initial Evaluation for Participation: Evaluation by the U.C. Davis V.M.T.H. Oncology or Soft Tissue Surgery services. Specific preoperative diagnostic tests to ensure that your pet is safe for surgical removal of the mast cell tumor will be recommended by the clinician that you consult with on these services.

Procedures: If you choose to enroll your dog, lymph node mapping procedures will be performed the day before and the day of surgery. These will be discussed in more detail at the time of your appointment.

Benefits: The study will cover costs associated with the sentinel lymph node mapping imaging. There is no charge to you for these procedures.

Possible benefits of participating in this study for your dog include more sensitive identification of metastasis (spread of cancer) if it is present. If early metastasis is more sensitively identified, we can then make more accurate treatment recommendations for your pet. It is our hope that in addition to benefiting your dog, we will benefit future patients by advancing the standard of care offered when treating this type of cancer, improving care provided to larger numbers of veterinary cancer patients.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for bringing your dog to the U.C. Davis V.M.T.H. for 1) preoperative evaluation of and 2) surgical removal of the mast cell tumor, and covering the standard costs associated with medical workup for and surgical removal of the mast cell tumor.

If you are calling to schedule an appointment and already know that you are interested in having your dog participate in this study, please inform the coordinators so that they can make sure to schedule appropriately for the mapping procedures.

Urinary Incontinence: Finding a Treatment

Title: Use of Radiofrequency Urethral Thermoplasty for the Treatment of Urinary Incontinence

Purpose of Study: The purpose of this project is to assess a novel treatment option for urinary incontinence in dogs.

Contact: Contact Dr. Culp for details at wculp@ucdavis.edu or call (530) 752-1393 to make an appointment.

Participation Requirements: Dogs with urinary incontinence

Initial Evaluation for Participation: Contact Dr. Culp for details at wculp@ucdavis.edu or call (530) 752-1393 to make an appointment.

Procedures: Dogs with a diagnosis of urinary incontinence and have been evaluated by a study investigator at UC Davis can be considered. Your dog will undergo testing related to urinary incontinence generally consisting of bloodwork, abdominal ultrasound and possibly cystourethroscopy (camera evaluation of the urethra and urinary bladder). Once your dog is deemed a candidate, and you have consented to have your dog enrolled, your dog will have the novel procedure performed.

Benefits: Enrolling a dog in this study results in a significant financial incentive towards diagnostics that would be recommended for your dog whether or not he/she is enrolled in the study. Additionally, this study will pay for the novel treatment.

Owner Responsibilities:

  • Bring your dog to the VMTH four separate times over approximately 6-weeks
  • Complete the study questionnaires
Osteoarthritis: Finding a Treatment for the Pain of Arthritis

Title: A Randomized, Placebo Controlled, Proof of Concept Study of the Efficacy of Two New Investigational Medications in the Treatment of Canine Osteoarthritis Pain

Purpose of Study: The primary purpose of this study is to test two investigational medications to determine if either one, or both, work to potentially decrease signs of pain of osteoarthritis in dogs.

Contact: Dr. Duane Robinson at darobinso@ucdavis.edu.

Participation Requirements: Dogs that are at least 2 years old with arthritis in one or more joints of the front and/or back legs. They must weigh 15-50kg (33-110 lbs) and be healthy with NO evidence of serious chronic disease (e.g., known or suspected invasive or metastatic cancer, endocrinologic, immune-mediated disease, cognitive dysfunction, liver disease, kidney disease, congestive heart failure, gastric or duodenal ulceration, inflammatory bowel disease). Please note that well-controlled thyroid disease is allowed.

Initial Evaluation for Participation: Please tell the study veterinarian and staff if your dog has participated in any other clinical trials or studies in the past and about ALL medications or supplements your dog is presently taking or has received in the past 6 months (including “joint health” treatments). Although not a complete list, your dog must not have received non-steroidal anti-inflammatory drugs (NSAIDs), COX-2 inhibitors, corticosteroids, opioids, herbal products indicated for pain relief or osteoarthritis, gabapentin, pentosan polysulphate, PSGAG, chiropractic manipulation, acupuncture, or acupressure therapy within 6 months of your initial visit.

Procedures: The study will last approximately 6 weeks (4 visits). If your dog qualifies for the study and you agree to participate, your dog will be randomly assigned to receive one of four medications: one of the two investigational medications, Carprofen (Rimadyl) or a placebo. You will be required to administer study medication to your dog by mouth (capsules) twice daily for approximately 14 days. Additionally, you will be given a daily diary that should be brought to the third visit to document when you gave the medication, any other treatments your dog received, and abnormal signs that your dog experiences to complete several questionnaires about your dog based on behavior from the previous week. The same person will need to bring the dog for each visit and will need to complete the diary.

  • Visits 1 and 2 (to determine eligibility):
    • Visit 1: We will do a physical and lameness examinations, take X-rays of the area of interest, and collect blood and urine sampling. Your dog may need sedation during the X-rays.
    • Visit 2: We will collect blood again, and if he/she qualifies for the study, your dog will receive the first dose of assigned medication during that visit. After the first dose is administered, your dog will need to stay at the clinic for at least an additional 3 hours for additional blood sample collections. Your dog’s assigned medication will be sent home with you for you to administer twice a day, as instructed by the study veterinarian or staff.
  • Telephone “visit” (phone call) approximately 7 days after the second office visit from the veterinary staff to see how your dog is doing.
  • Visit 3 will occur approximately two weeks after Visit 2. Your dog will need to stay at the clinic for at least 3 hours after receiving the last dose to have additional blood samples collected.
  • Visit 4 (final safety follow-up visit): Approximately two weeks after Visit 3, we will follow-up on the health of your dog and collect blood and urine samples.

Benefits: The study will cover the costs of all study procedures, including the study’s required radiographs (and associated sedatives if needed), office visits, and laboratory tests. Upon completion of the study, you will be eligible to receive a $150 Visa gift card. If your dog experiences any adverse events (uncomfortable, severe or life-threatening), the sponsor will cover the reasonable and necessary veterinary fees and expenses related to the event; however you will be responsible for any veterinary care and costs for your dog thereafter.

We cannot promise any benefits to your dog or other animals from your taking part in this clinical trial; however, possible benefits include direct relief of pain due to arthritis in your dog. As a result of this study, we hope to learn more about osteoarthritis, and determine how the assigned medicines may help osteoarthritis pain. The medicines being tested could be further developed for either animals or humans.

Owner Responsibilities:

  • Bring your dog to the VMTH four separate times over approximately 6-weeks
  • Administer the study medication to your dog by mouth (capsules) twice daily for approximately 14 days with or without food
  • Complete the required daily diary accurately and fully each day for approximately 2 weeks

Printable Flyer (PDF)

ON HOLD! Bloat (Gastric Dilation and Volvulus): Investigating a Preventative Surgical Technique

Title: Investigating Minimally Invasive Techniques for the Performance of Gastropexy

Purpose of Study: Commonly referred to as "bloat", gastric dilation and volvulus (GDV) is a life-threatening syndrome that occurs when a dog’s stomach becomes distended with air and/or food and rotates. The rotation of the stomach restricts outflow of stomach contents and more importantly causes a reduction in the blood flow to the stomach wall causing death of the tissues. This disease is considered universally fatal if left untreated. Additionally, if the stomach wall is devitalized from lack of blood flow, significant post-operative care may be necessary making this surgery cost prohibitive for many owners and resulting in humane euthanasia. Performing a gastropexy has been shown to virtually eliminate the possibility of a subsequent torsion.

Hiatal Hernia / Brachycephalic Obstructor Syndrome: Assessing a Surgical Treatment

Title: Effect of Surgical Treatment of Brachycephalic Obstructor Syndrome on the Lower Esophageal Area of Brachycephalic Dogs with Evidence of Hiatal Herniation and Gastroesophageal Reflux

Purpose of Study: We believe that brachycephalic dogs have a tendency to develop hiatal herniation (HH) with greater frequency than non-brachycephalic dogs. Dogs with relative obstruction of the upper airways may generate a decreased pressure in their chest during inspiration (breathing in) that results in the upper part of the stomach being sucked into the chest (HH). This can lead to clinical signs including regurgitation, esophageal stricture formation and aspiration pneumonia if severe. We hypothesize that, if the upper airway obstruction in these dogs can be alleviated, improvement in their respiratory compromise might be seen as well as a reduction in the severity of their HH.

Contact:

  • Please call (530) 752-1393 to make an appointment with Soft Tissue Surgery or Internal Medicine for Dr. Phil Mayhew's study
  • Email Dr. Phil Mayhew directly at philmayhew@gmail.com

Participation Requirements:

  • Brachycephalic breed (dogs with broad short skulls)
  • No evidence of other upper airway obstructive pathology (especially tracheal collapse and hypoplastic trachea)
  • No previous brachycephalic surgery
  • Evidence of hiatal herniation on fluoroscopic imaging (performed pre-operatively)

Initial Evaluation for Participation: Initial evaluation and discussion for entry into the study can be arranged by making an appointment with our Internal Medicine or Soft Tissue Surgery or by contacting Dr. Phil Mayhew directly (contact information below).

Procedures: Both visits outlined below require hospitalization for 2-4 days at the VMTH.

  • First visit:
    • Day 1: You will be asked to fill out a questionnaire about your dog’s clinical signs. We will give your dog a local anesthetic, place a small catheter down your dogs nose, and give your dog a small amount of water to swallow, so we can trace the pressure profile of your dog’s esophagus (known as high-resolution manometry or HRM study). We will then perform a barium esophagram, which involves imaging of your dog using a fluoroscope (moving x-ray machine) after he/she swallows water and food boluses. Finally, we will place a small pH-monitoring probe in you dog’s nose that will remain in place for no longer than 24-hours for continuous monitoring of the esophageal pH and will be removed prior to surgery the following day.
    • Day 2: Your dog will be prepared for surgery and given general anesthesia. Prior to surgery, we will take measurements of your dog’s lower esophageal area (impedance planimetry or Endoflip), which involves inflation of a very low-pressure balloon within the lower esophagus, and perform an upper gastrointestinal endoscopic study immediately before upper airway surgery.
  • 30 – 60 days post-surgery visit: You will need to bring your dog in for another visit between 30 and 60 days after surgery. During this visit, we need to repeat the questionnaire and the procedures outlined above to gauge the response to surgery.

Benefits: The trial will pay for all of the diagnostic tests associated with the study, including costs associated with the HRM and esophagram studies, Endoflip measurements, pH impedance studies, endosocopic studies, biopsy procedures, pathology fees as well as the hospitalization and anesthesia fees associated with the second visit to the hospital at 30-60 days post-operatively. The owner will have to cover the surgical procedure, hospitalization and any possible complications associated with the surgical procedure and recovery during the first visit.

We cannot promise any benefits to your dog or other animals from your taking part in this clinical trial; however, possible benefits include a better understanding of your dogs presence or absence of hiatal herniation which may aid in longer-term management of this component of his or her clinical signs. Results from this study may influence treatment of other dogs with similar conditions going forward.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for bringing the dog to the VMTH for the study-related visits for the duration of the time stipulated and for providing the clinical information stipulated.

Printable Flyer (PDF)

Imaging: Sentinel Lymph Node Mapping

Title: Identification of sentinel lymph nodes with intraoperative fluorescence

Purpose of Study: Near-infrared fluorescent imaging utilizes special wavelengths of light to identify important structures, and is used in surgery to improve surgical decision making. The fluorescent light is generated by a special contrast agent (a “fluorophore”) that is injected into the patient. When a special light source is used to illuminate the surgical site, any tissue in which this fluorophore is located will glow, aiding the surgeon in identifying the location or extent of disease. Based on early experiments in rodents and human clinical trials, this very sensitive tool has the potential to improve surgical decision-making and improve overall treatment for a wide variety of diseases. The purpose of this study is to evaluate the efficacy of this imaging modality in veterinary patients presenting with natural disease processes.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey.

Participation Requirements: Dogs scheduled for surgery to treat their primary tumor, and for whom clients are interested in improving their pet’s staging information by lymph node biopsy. Dogs most likely to benefit from this technique include those with primary lung tumors, mast cell tumors, oral cancers, and carcinomas in general, as these are types of tumors that tend to exhibit spread by the lymphatic system. Tumors may be external (skin associated) or internal. Dogs with severe kidney or liver disease are not eligible to participate.

Initial Evaluation for Participation: Evaluation by Dr. Michele Steffey on the Soft Tissue Surgery Service.

Procedures: The best fluorophore for your pet’s tumor will be administered either subcutaneously or intravenously, at a dose and timing considered to be optimal by your attending veterinarian.

Benefits: Preliminary, not yet published results have demonstrated that the fluorescent imaging is very helpful in locating the important lymph nodes at surgery, which often reduces the amount of dissection needed, and may reduce the amount of time under anesthesia. The purpose of this study is to aid in identifying lymph nodes for improved staging (lymph node biopsy) at the time your pet’s primary tumor is removed. It is hoped, but is not known, if there will be a specific benefit to your individual pet. Depending upon your pet’s specific tumor type and the biopsy results, use of this technique and lymph node biopsy may or may not impact the postoperative treatment recommendations provided to your dog.

Owner Responsibilities: The cost of the fluorophore and special imaging is covered by the study. There are no risks associated with the imaging itself, as it only involves light; there is no radiation exposure to the patient. The fluorophores used in this study are FDA-approved for use in humans and have been used without complication in our hospital for the past 18 months. The primary risk of this procedure is associated with injection of these drugs is an allergic reaction, which is very rare, but unpredictable in an individual patient (like any other drug reaction, including antibiotics). If an allergic reaction should occur, immediate costs of treatment (immediate supportive medications, support of blood pressure) will be covered by the study; however, the owner will be responsible for any treatment costs for prolonged or severe complications.

Intrahepatic Portosystemic Shunts: Assessing a New Treatment Technique

Title: Assessment of Outcome in Dogs Undergoing Percutaneous Transvenous Coil Embolization to Treat Intrahepatic Portosystemic Shunts

Purpose of Study: The purposes of this project are to assess the response to treatment of a relatively new treatment option (coil embolization) for intrahepatic portosystemic shunts that has shown tremendous potential.

Contact: Contact Dr. Culp for details at wculp@ucdavis.edu or call (530) 752-1393 to make an appointment.

Participation Requirements: Dogs with intrahepatic portosystemic shunts

Initial Evaluation for Participation, Procedures, Benefits and Owner Responsibilities: Contact Dr. Culp for details at wculp@ucdavis.edu or call (530) 752-1393 to make an appointment.

Procedures: Dogs with a diagnosis of intrahepatic portosystemic shunts (IHPSS) will be enrolled in the study. The dog will undergo percutanous transvenous coil embolization (PTCE) to treat his/her IHPSS.

Large Bowel Disease: Evaluating New Diagnostic Tool

Title: Evaluation of CT pneumocolonography as a diagnostic tool for large bowel disease in dogs

Purpose of Study: The purpose of this study is to evaluate the impact of imaging findings on surgical decision-making in dogs with colonic and rectal disease of any kind (cancer or non-cancer). This part of the body can be a very difficult region examine with current imaging methods, which also do not provide optimal spatial information important if a surgical procedure is needed. In early studies, we have demonstrated the safety and efficacy of the CT pneumocolonography procedure in normal dogs, but it is important that we learn to accurately interpret the imaging findings for a wide variety of disease processes in clinical patients so that our CT diagnoses are accurate. Our goal is to compare the imaging findings obtained with CT pneumocolonography with the current standard of care of colonoscopy and colonoscopic biopsies.

Contact: Call 530-752-1393 to schedule an appointment with the Internal Medicine Service. When scheduling, please indicate your interest in the CT pneumocolonography study with Dr. Steffey/Dr Marks.

Participation Requirements: In order to participate in this study, a colonoscopic exam must have been recommended for workup of your dog’s problem, and your dog must be scheduled to receive a colonoscopic exam under general anesthesia at UC Davis.

Initial Evaluation for Participation: None.

Procedures: If you agree to participate, your dog will receive a CT scan (with and without intravenous contrast material) in conjunction with carbon dioxide gas insufflated into the rectal lumen. Following CT pneumocolonography, your dog will receive the scheduled colonoscopy, which is the current standard of care for assessment of these masses, and if clinically indicated for the care of your dog, colonic biopsies or surgery will be obtained according to your discussion with your attending clinician.

Benefits: In return for participation in this study, your dog will receive a free CT scan (an approximately $800 value to you), which may directly benefit your dog, as it can provide important information for treatment recommendations that other types of imaging cannot. CT evaluation of local lymph nodes is an additional benefit as CT has been demonstrated to be very helpful in the evaluation of regional lymph nodes for metastatic disease in other types of cancer in other locations.

Owner Responsibilities: There is no additional cost to you for your dog’s participation in the study. You are financially responsible for hospital costs associated with the standard care of your dog, including abdominal ultrasound, general anesthesia, colonoscopy, hospitalization, biopsies, and any other diagnostic tests recommended for evaluation of your dog’s disease by your attending clinician.

Lung Tumors: Identifying Lymph Node Metastasis

Title: Assessment of methods of improving identification of regional lymph nodes in patients with lung cancer

Purpose of Study: Knowing whether or not there is metastatic tumor in the regional lymph nodes is very important prognostic information for dogs with lung tumors, as dogs that do not have metastatic disease in their lymph nodes in general have a much longer lifespan. Chemotherapy is often recommended for patients who have metastatic disease, but is not recommended for dogs who do not have metastatic spread. The aim of this study is to provide information that will allow us to better identify these lymph nodes at surgery, to improve the safety of surgical dissection, and to minimize surgical time during removal of these lymph nodes.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey.

Participation Requirements:

  • A diagnosis of a solitary lung tumor
  • Your decision to pursue surgical removal of your dog’s lung tumor

Initial Evaluation for Participation: Evaluation by the V.M.T.H. Small Animal Surgery, Internal Medicine, or Oncology services. A CT scan at the VMTH is part of the normal expected surgical planning for lung tumor surgery at our institution, and is the financial responsibility of the client, but may be performed under the same anesthetic episode as the planned surgery. Dogs with severe kidney or liver disease are not eligible to participate.

Procedures: During CT and surgery, special dyes will be injected intravenously or into the lung around your dog’s tumor and uptake by the regional lymph nodes will be assessed.

Benefits: Information regarding the status of your dog’s lymph nodes is very important in prognosis for this disease. This technique will help surgeons to identify and more safely remove your dog's lymph nodes at surgery; pathology of the removed lymph node(s) will provide improved information to direct recommendations that we an give you for postoperative care and treatment. If based on the initial CT results you elect to have your dog goes to surgery as part of this study, the study will retroactively pay for the cost of your dog’s CT scan (a $900 value to you).

Owner Responsibilities: There is no anticipated additional cost to you for your dog’s participation in the study. The cost of the dyes and operative imaging are covered by the study. The primary risks of this procedure are 1) allergic reaction to the drugs used to identify the lymph nodes (very rare, but unpredictable in an individual patient (like any other drug reaction, including antibiotics)), and 2) air leakage from the lung at the site of the injection (if it occurs, this should be a short term problem, as removal of the affected lung will be performed as part of the tumor removal). If an allergic reaction should occur, immediate costs of treatment (immediate supportive medications, support of blood pressure) will be covered by the study; however, the owner will be responsible for any treatment costs for prolonged or severe complications. Standard anesthetic and surgical risks of lung surgery and lymph node surgery will apply and will be discussed at the time of your visit.

Nasal cancer: Using a Combination of Therapies for Treatment

Title: Nasal tumors: Intra-arterial Chemotherapy and Radiotherapy to Treat Nasal Carcinoma

Purpose of Study: The purpose of this study is to prospectively evaluate the response of nasal cancer to a combination of therapies (chemotherapy and radiation therapy) in dogs.

Contact: Contact Dr. Culp for details at wculp@ucdavis.edu or (530) 752-1393.

Participation Requirements: Dogs diagnosed with nasal tumors

Initial Evaluation for Participation: Contact Dr. Culp for details at wculp@ucdavis.edu or (530) 752-1393.

Procedures: Dogs that are scheduled to receive radiation therapy for the treatment of nasal cancer can be enrolled in the study. Dogs will be placed into a group receiving radiation therapy alone or with chemotherapy.  Response to these treatments will be assessed with CT scans (done before and after treatment).

Benefits: The CT scans, chemotherapy administration, and part of the radiation therapy will be paid for by the study.

Owner Responsibilities: The owner will be responsible for providing follow-up information to the treating clinicians and returning the dog 4 weeks after initiation of radiation therapy for a second CT evaluation (the first is performed prior to treatment).

Prostate cancer: Evaluating Embolization as a Treatment Option

Title: Evaluation of the Use of Embolization in the Treatment of Prostatic Neoplasia

Purpose of Study: The purpose of this project is to describe the procedure of prostatic artery embolization in a group of dogs with naturally-occurring prostate cancer. A secondary objective is to evaluate the effect that prostatic artery embolization has on clinical signs and the size of the tumor.

Contact: Contact Dr. Culp for details at wculp@ucdavis.edu or (530) 752-1393.

Participation Requirements: Dogs with prostate cancer

Initial Evaluation for Participation: Contact Dr. Culp for details at wculp@ucdavis.edu or (530) 752-1393.

Procedures: Dogs will undergo prostatic artery embolization. Pre-procedural ultrasound imaging and computed tomographic findings will be compared to post-procedural ultrasound imaging and computed tomographic findings. Complications associated with the procedure will be recorded and owners will receive a questionnaire to assess the clinical signs of the dog both pre- and post-procedure.

Benefits: The benefits of enrolling in this study include financial support for both pre- and post-procedure diagnostics. Additionally, funding from this grant will be applied towards the procedure. We hope that the data acquired in this study will allow us to advance the treatment of cancer in both dogs and people.

Owner Responsibilities: The owner will be responsible for scheduling appointments (initial and 1 month follow-up) and keeping those appointments as required by protocol.

Prostate, Urethra and/or Bladder Tumors: Evaluating Urethral Stent Outcomes

Title: Outcome Associated with Urethral Stent Placement

Purpose of Study: The purpose of this project is to determine the outcome of dogs with cancer-induced urethral obstructions and in dogs with urethral stents.

Contact: Contact Dr. Culp for details at wculp@ucdavis.edu or or call (530) 752-1393 to make an appointment.

Participation Requirements: Dogs with tumors causing obstruction of the urethra (bladder, urethra and prostate)

Initial Evaluation for Participation, Procedures, Benefits, and Owner Responsibilities: Contact Dr. Culp for details at wculp@ucdavis.edu or (530) 752-1393.

Nasolacrimal Apparatus Blockage: A multidisciplinary, minimally invasive treatment

Title: Stenting as a Treatment for Nasolacrimal Apparatus Obstruction

Purpose of Study: Tears from the ocular surface are drained from the eye through several important structures collectively known as the nasolacrimal apparatus (NLA). This frequently becomes blocked and sometimes infected leading to discomfort, tear staining, eye discharge, and skin inflammation, all of which are associated with a decreased quality of life. Clinically, NLA obstructions can be very frustrating to treat and can often lead to permanent obstruction.

We have established a team at the UC Davis Veterinary Medical Teaching Hospital consisting of specialists with expertise in Ophthalmology, Internal Medicine, Endoscopy, Diagnostic Imaging, and Interventional Radiology and have utilized fluoroscopy to successfully treat NLA obstruction in dogs. We have utilized fluoroscopy, CT, and endoscopy and capitalized on improvements in instrumentation and minimally invasive techniques developed for catheterization of other challenging locations such as the ureters to successfully treat NLA obstruction.

To date, our team has successfully cannulated the nasolacrimal duct of 5 dogs and 1 horse referred for NLA obstruction, all of which we have managed and monitored for at least 8 weeks here at the VMTH. The initial clinical response in these patients has been extremely encouraging with all 6 cases demonstrating what the owners define as complete resolution of signs.

Based upon the success of this initial pilot study, we have initiated a clinical trial to recruit and treat more cases and to evaluate more objective outcome measures.

Contact: Please call 530-752-3937 to schedule your initial visit to the UC Davis Veterinary Ophthalmology Service

Participation Requirements: Dogs demonstrating signs of nasolacrimal apparatus (NLA) blockage

Initial Evaluation for Participation: None

Procedures: After an initial examination at the UCD VMTH to ensure the patient meets study entry criteria, owners will provide informed consent and complete a questionnaire concerning their dog’s signs. Patients will then undergo initial testing including CT scanning of the NLA, and NLA stenting using endoscopy and fluoroscopy. The stent will be left in position for at least 6 weeks. After stent removal, similar testing including CT scanning will again be performed, and owners will repeat the same questionnaire. Diagnostic test results from before and after stenting will be compared. Some financial subsidization of case management costs is available through the clinical trial.

Benefits: The study will subsidize costs associated with the second CT scan. Based upon results from the 6 patients in the pilot study, it is possible but not assured that your pet will have reduction or resolution of signs associated with NLA obstruction. Information acquired during this study will allow us to advance the treatment for NLA blockage for veterinary patients worldwide.

Owner Responsibilities: You will be responsible for all costs except those associated with the repeat CT scan following stent removal. Additionally, you will need to bring your dog to the VMTH for all scheduled appointments including a follow-up visit at least 6-8 weeks after the procedure. Lastly, you will be required to complete questionnaires prior to and after the NLA stenting procedure

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Variety of Tumors: Assessing Minimally Invasive Tumor Ablation

Title: Thermal ablation of cancer in dogs and cats

Purpose of Study: The purpose of this study is to evaluate the outcome of treating veterinary patients with minimally invasive tumor ablation technologies including cryoablation and microwave ablation. These methods are growing in the treatment of a variety of cancers in the human medical field, but information in veterinary patients is currently very limited. To date we have completed a study on cryoablation in nasal tumor patients, and this technique has been very successful in reducing tumor volume in nasal tumor patients – although there are no more spots in the formal nasal tumor study, because of this success, we continue to offer this technique as a clinical service to nasal cancer patients, and are expanding the types of cancer that we are evaluating.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey. The coordinators will likely advise you to send your pet's medical records and imaging results for Dr. Steffey's review. If, based on this information, your pet is deemed an appropriate candidate, an appointment will be scheduled.

Participation Requirements: In order to participate in this study, your pet must have **solitary** malignant soft tissue or bony mass **that is deemed amenable to ablation**. Tumor types that MAY be amenable to this treatment include lung tumors, kidney tumors, adrenal tumors, and bone tumors in certain locations. however determination of eligibility is complex and relates to the size of the lesion as well as proximity to/involvement of other important nearby structures. Tumors that are superficial (involving or near to the skin) or that involve the gastrointestinal tract are not amenable to this treatment.

Initial Evaluation for Participation: Evaluation by the V.M.T.H. Small Animal Surgery, Internal Medicine, or Oncology services.

Procedures: If you agree to participate, under general anesthesia, ablation probes will be placed into your pet’s mass under ultrasound guidance and the tumor will be ablated.

Benefits: This treatment method may only be palliative, but it is our hope that in appropriately selected patients, we may improve quality of life as well as longevity.

Owner Responsibilities: The study will cover the cost of the ablation probes and generator. Costs of pre-operative workup, general anesthesia, recommended imaging, hospitalization, and general management of the disease process or any complications that occur during treatment are your responsibility.

Variety of Tumors and Diseases: Improving Operative Detection of Tumors

Title: Fluorescent imaging of cancer

Purpose of Study: Near-infrared fluorescent imaging utilizes special wavelengths of light to identify important structures, and is used in surgery to improve surgical decision making. The fluorescent light is generated by a special contrast agent (a “fluorophore”) that is injected into the patient. When a special light source is used to illuminate the surgical site, any tissue in which this fluorophore is located will glow, aiding the surgeon in identifying the location or extent of disease. Based on early experiments in rodents and human clinical trials, this very sensitive tool has the potential to improve surgical decision-making and improve overall treatment for a wide variety of diseases. The purpose of this study is to evaluate the efficacy of this imaging modality in veterinary patients presenting with naturally occurring neuroendocrine tumors disease processes.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey.

Participation Requirements: Dogs with the following conditions are most likely to benefit from this study: hyperparathyroidism, thyroid cancer, pancreatic cancer, adrenal cancer, thymoma, mammary (breast) cancer, lung cancer, anal sac gland cancer, oral cancer, mast cell tumor. Dogs with severe kidney or liver disease are not eligible to participate.

Initial Evaluation for Participation: Evaluation by the V.M.T.H. Small Animal Surgery, Internal Medicine, or Oncology services.

Procedures: If you agree to participate, the best fluorophore for your pet’s tumor will be administered or intravenously, at a dose and timing considered to be optimal by your attending veterinarian.

Benefits: It is hoped, but is not known if there will be a specific benefit to your individual pet. Fluorescent imaging may or may not improve operative localization and dissection of your pet’s tumor.

Owner Responsibilities: Costs of standard pre-operative workup, general anesthesia, recommended imaging, hospitalization, and general management of your pet’s disease process or any complications that occur during treatment are your responsibility. The cost of the fluorophore and special imaging is covered by the study. There are no risks associated with the imaging itself, as it only involves light; there is no radiation exposure to the patient. The fluorophores used in this study are FDA-approved for use in humans and have been used without complication in our hospital for the past 18 months. The primary risk of this procedure is associated with injection of these drugs is an allergic reaction, which is very rare, but unpredictable in an individual patient (like any other drug reaction, including antibiotics). If an allergic reaction should occur, immediate costs of treatment (immediate supportive medications, support of blood pressure) will be covered by the study; however, the owner will be responsible for any treatment costs for prolonged or severe complications.

Variety of Tumors: Sentinel Lymph Node Mapping

Title: Identification of sentinel lymph nodes with intraoperative fluorescence

Purpose of Study: Near-infrared fluorescent imaging utilizes special wavelengths of light to identify important structures, and is used in surgery to improve surgical decision making. The fluorescent light is generated by a special contrast agent (a “fluorophore”) that is injected into the patient. When a special light source is used to illuminate the surgical site, any tissue in which this fluorophore is located will glow, aiding the surgeon in identifying the location or extent of disease. Based on early experiments in rodents and human clinical trials, this very sensitive tool has the potential to improve surgical decision-making and improve overall treatment for a wide variety of diseases. The purpose of this study is to evaluate the efficacy of this imaging modality in veterinary patients presenting with natural disease processes.

Contact: Call 530-752-1393 and ask to speak to the Soft Tissue Surgery scheduling coordinators to schedule an appointment with Dr. Michele Steffey.

Participation Requirements: Dogs scheduled for surgery to treat their primary tumor, and for whom clients are interested in improving their pet’s staging information by lymph node biopsy. Dogs most likely to benefit from this technique include those with primary lung tumors, mast cell tumors, oral cancers, and carcinomas in general, as these are types of tumors that tend to exhibit spread by the lymphatic system. Tumors may be external (skin associated) or internal. Dogs with severe kidney or liver disease are not eligible to participate.

Initial Evaluation for Participation: Evaluation by Dr. Michele Steffey on the Soft Tissue Surgery Service.

Procedures: The best fluorophore for your pet’s tumor will be administered either subcutaneously or intravenously, at a dose and timing considered to be optimal by your attending veterinarian.

Benefits: Preliminary, not yet published results have demonstrated that the fluorescent imaging is very helpful in locating the important lymph nodes at surgery, which often reduces the amount of dissection needed, and may reduce the amount of time under anesthesia. The purpose of this study is to aid in identifying lymph nodes for improved staging (lymph node biopsy) at the time your pet’s primary tumor is removed. It is hoped, but is not known, if there will be a specific benefit to your individual pet. Depending upon your pet’s specific tumor type and the biopsy results, use of this technique and lymph node biopsy may or may not impact the postoperative treatment recommendations provided to your dog.

Owner Responsibilities: The cost of the fluorophore and special imaging is covered by the study. There are no risks associated with the imaging itself, as it only involves light; there is no radiation exposure to the patient. The fluorophores used in this study are FDA-approved for use in humans and have been used without complication in our hospital for the past 18 months. The primary risk of this procedure is associated with injection of these drugs is an allergic reaction, which is very rare, but unpredictable in an individual patient (like any other drug reaction, including antibiotics). If an allergic reaction should occur, immediate costs of treatment (immediate supportive medications, support of blood pressure) will be covered by the study; however, the owner will be responsible for any treatment costs for prolonged or severe complications.