Soft Tissue Surgery

Photo: Flyer for Hiatal Herniation / Brachycephalic Obstructor Syndrome 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 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

Ureteral obstructions: Evaluating Post-Surgery Outcomes

Title: Evaluation of Post-operative Outcome in Cats Undergoing Ureteral Stent Placement to Relieve Ureteral Obstruction

Purpose of Study: The purpose of this project is to record the intra-operative and postoperative complications associated with the procedure and determine the outcome of the procedure based on objective measures.

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

Participation Requirements: Cats with benign ureteral obstruction

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

Procedures: Cats with a diagnosis of benign ureteral obstruction will be enrolled in the study. Bloodwork values that can be utilized to determine the function of the kidney (should improve with the passage of urine) as well as variables such as the size of the kidney collecting system and ureter (should decrease with passage of urine) in cats both pre- and postoperatively will be evaluated. Lastly, the change in the urine output of cats with ureteral stents will be assessed to determine if the stents improve output.

Benefits: The benefits of enrolling a patient in this study are financial. Some of the pre- and post-stent placement bloodwork and pre- and post-stent placement ultrasound evaluations will be paid for by the study.

If this therapy proves to be beneficial, it will have important clinical applications for other cats with the same condition.

Owner Responsibilities: The owner is responsible for returning with their cat 2 weeks and 3 months after stent placement.

Read about Googgie, a 17-week-old Sphynx, that was helped by participating in this trial!

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 coordinator 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 VMTH 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 coordinator 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 VMTH 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

Chylothorax: Assessing a New Treatment

Title: Treatment of chylothorax in dogs

Purpose: The traditional combination of thoracic duct ligation and pericardectomy has been performed for many years. However, without good evidence of pericardial disease, the pericardectomy may not be necessary. This study aims to assess the effectiveness of doing a complete thoracic duct ligation alone in resolving chyle accumulation and provide a better understanding of the physiological response to thoracic duct ligation in dogs with idiopathic chylothorax.

Contact: Dr. Philipp Mayhew (philmayhew@gmail.com) or make an appointment with Soft Tissue Surgery by calling (530) 752-1393

Participation Requirements:

  • Inclusion Criteria: Dogs diagnosed with idiopathic chylothorax
  • Exclusion Criteria: Dogs that have been diagnosed with any significant degree of pericardial disease or other underlying etiologies (non-idiopathic chylothorax)

Initial Evaluation for Participation: Prior to being accepted into the study, patients will have to have undergone a thorough diagnostic assessment to rule out underlying causes and confirm a diagnosis of idiopathic chylothorax (IC), which must include a complete blood count and biochemistry screen completed within a month from the date of surgery. Triglyceride levels assayed in the serum and in the pleural effusion must confirm the diagnosis of IC and a heart worm antigen test must be negative. Patients must also have undergone thoracic radiographs and abdominal ultrasonography.

Procedures: 

  • A computed tomography (CT) study under anesthesia to assess your dog’s lymphatic anatomy and then cardiac catheterization procedure and echocardiogram to rule out significant pericardial disease
  • If no significant pericardial disease is present, your dog will be enrolled in the study.
    • On the following day: Complete thoracic duct ligation, near-infrared fluorescence imaging and a second CT study under anesthesia to confirm complete occlusion of all thoracic duct chyle flow
    • Follow-up visits:
      • Three to 6-months post-surgery for a follow-up CT study
      • Nine months to 1-year post-surgery for chest x-rays

Benefits: The study will cover costs for some of the diagnostic tests and a portion of the surgical procedure, including the echocardiogram, near-infrared intraoperative imaging, cardiac catheterization procedures, all CT studies, hospitalization for the second visit to the hospital, and the anesthesia fees at the second visit (at 3-6 months post-operatively). Additionally, the study will provide a $1000 credit towards the cost of the surgical procedures.

Results from this study will provide us with a better understanding of your dog’s lymphatic anatomy and disease state, aid in longer-term management of this component of his or her clinical signs, and may influence treatment of other dogs with chylothorax in the future.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for bringing the dog to the VMTH for all study-related visits. Additionally, you will need to cover any costs related to complications and some of the costs associated with the surgical procedure (e.g., surgical procedure and related fees, anesthesia for surgery, ICU fees and hospitalization fees associated with the first visit).

Printable Flyer (PDF)

Liver Tumors: Using a New Technique to Shrink Tumors

Title: Prospective Evaluation of the Use of Transarterial Embolization in the Treatment of Liver Neoplasia

Purpose: When liver tumors in dogs cannot be removed with surgery, treatment options are limited or non-existent. In humans, one of the standard treatments for those cases is transarterial embolization (TAE), which eliminates the blood supply of the tumor and may decrease tumor size. Therefore, the objectives of this study are to 1) describe the procedure of TAE in a group of dogs with naturally-occurring liver cancer, and 2) evaluate the effect that liver TAE has on clinical signs and the size of the tumor.

Contact: Dr. Bill Culp (wculp@ucdavis.edu) or make an appointment by calling (530) 752-1393

Participation Requirements: Dogs diagnosed with liver cancer that has been determined to be non-removable or in a location with great surgical risk

Initial Evaluation for Participation: To be performed by Dr. Culp

Procedures: If you agree to have your dog participate in this study, the following procedures will occur:

  • An abdominal ultrasound scan
  • CT scan, PET scan and TAE while under anesthesia
  • A second ultrasound scan, CT scan and PET scan approximately 4 weeks post-TAE
  • Hospitalization for 1-2 days post treatment pending response to treatment
  • Completion of questionnaires

Benefits: The study will cover costs associated with the ultrasounds, CT scans, PET scans and anesthesia.

We hope that the data acquired in this study will allow us to advance the treatment of cancer in both pets and people.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for keeping all scheduled appointments, completing several questionnaires, and covering costs associated with the TAE procedure and any complications that may occur as part of that procedure.

Urinary Incontinence: Using a New Device for Treatment

Title: Use of radiofrequency urethral thermoplasty for the treatment of urinary incontinence

Purpose: Medical therapy using either phenylpropanolamine or synthetic estrogen, alone or in combination is currently considered first line medical therapy for urinary incontinence. While studies have shown that these medications are effective in some patients, both have potential side effects and life-long therapy is generally required. Various surgical treatment options have also been described for those dogs that do not respond to medical management or experience adverse effects from medications; however, these procedures are invasive, require considerable surgical skill to perform and are not always successful. Therefore, the purpose of this study is to test a new device, which uses heat to alter the structure of collagen in the wall of the urethra and thereby strengthen the wall and decrease leakage), to treat urinary incontinence in female dogs.

Contact: Dr. Bill Culp (wculp@ucdavis.edu), Dr. Carrie Palm (cpalm@ucdavis.eduor make an appointment by calling (530) 752-1393

Participation Requirements: Female dogs demonstrating signs of urinary incontinence

Initial Evaluation for Participation: To be performed by Dr. Palm or Dr. Culp

Procedures: 

  • Testing related to urinary incontinence, including bloodwork, abdominal ultrasound and possibly cystourethroscopy (camera evaluation of the urethra and urinary bladder)
  • Urethral procedure under general anesthesia once your dog is deemed a candidate

Benefits: The study will cover costs associated with anesthesia, the urethral procedure and hospitalization.

We hope that the data acquired in this study will allow us to advance the treatment of our canine patients.

Owner Responsibilities: This study requires 1-year time commitment, although future follow-up may be recommended. You will be responsible for covering costs associated with initial diagnostics including bloodwork, abdominal ultrasound and cystourethroscopy, keeping all scheduled appointments and follow-up visits, and filling out a urination diary throughout the study.

Printable Flyer (PDF)

Prostate/Bladder/Urethra Tumors: Assessing the Outcome Associated with Urethral Stents and Utilizing New Techniques for Placement

Title: Prospective Evaluation of Outcome and the Use of Transrectal Ultrasound Associated with Urethral Stent Placement in Dogs with Lower Urinary Tract Neoplasia

Purpose of Study: Cancer resulting in obstruction of the lower urinary tract of dogs is most commonly found in the prostate, urinary bladder and urethra (tube responsible for draining urine out of the body). Unfortunately, cancer of the lower urinary tract often results in complete blockage of the urethra, causing a patient to be unable to pass urine. The inability to urinate is a life-threatening emergency.

The placement of urethral stents is generally performed with fluoroscopic-guidance (use of “real-time” x-rays). While fluoroscopy is useful for stent placement, there may be other techniques that could be considered. Traditionally, ultrasonographic assessment of tumor size and location has been performed by transabdominal ultrasound (where the ultrasound probe is placed on the abdominal wall to allow for visualization of organs within the abdomen), but this method can be inaccurate. The use of transrectal ultrasound (where an ultrasound probe is placed into the rectum) circumvents these previously discussed problems, and therefore, the purpose of this study is to evaluate this technique for efficacy.

Contact: Dr. Culp at wculp@ucdavis.edu or make an appointment by calling (530) 752-1393

Participation Requirements: Dogs with a diagnosis of prostatic, bladder or urethral cancer and secondary urethral obstruction for whom a stent is being offered/recommended and believed to be clinically beneficial

Initial Evaluation for Participation: Consultation with Dr. Culp

Procedures:

  • Transrectal ultrasound (TRUS), fluoroscopy (real time “x-rays”) and urethral stent placement under anesthesia
  • Completion of questionnaires pre-stent placement, 2-weeks post-stent placement and 3-months post-stent placement to assess outcome

Benefits: The study will cover the fluoroscopy, ultrasound, and anesthesia.

Benefits of enrolling in this study include financial support for the ultrasound, stent placement and anesthesia. We hope that the data acquired in this study will allow us to advance the treatment of cancer in both pets and people.

Owner Responsibilities: You will be responsible for covering equipment costs associated with the urethral stent placement and any complications of the procedure, keeping all scheduled appointments and completing a questionnaire pre-stent placement, 2 weeks after stent placement and 3 months after stent placement.

Printable Flyer (PDF)

Oral Tumors: Optimizing the Identification of Tumor Spread To Lymph Nodes

Title: Preoperative sentinel lymph node mapping in dogs

Purpose of Study: Successful treatment of many cancers depends on the extent of disease present at the time of diagnosis, and on accurate detection of that disease. Some oral cancers commonly spread from the mouth to nearby lymph nodes. Lymph node metastasis, if present, can influence the prognosis and treatment recommendations made for a patient. Currently, however, our standard veterinary staging protocol (aspiration cytology of the geographically nearest lymph node) misses a diagnosis of lymph node metastasis in a concerning number of patients. Because lymphatic pathways and lymph nodes of the head are very complicated and the closest lymph node is not necessarily the most likely to show disease, it is possible to miss disease because we do not know which is the best lymph node to evaluate. Lymph node mapping, a technique to visualize the lymphatic drainage of tumors, is increasingly used to improve cancer staging and treatment protocols in the treatment of cancer in people. Mapping allows identification of the “sentinel lymph node,” or lymph node that is most likely to demonstrate evidence of metastatic disease. This lymph node can then be aspirated or surgically removed with the primary tumor to be evaluated microscopically for spread of cancer. This trial is being performed to optimize a method of sentinel lymph node mapping that can be accessible to a greater number of veterinary practitioners in an effort to improve the accuracy of cancer diagnoses and treatment recommendations we make for our veterinary patients, improving their quality of life and length of time with us following diagnosis with this cancer.

Contact: If you are interested in determining whether your dog is eligible for the trial, please schedule an appointment for evaluation with one of the participating clinical services by calling the Small Animal Clinic at (530) 752-1393 for either Soft Tissue Surgery, Dentistry and Oral Surgery, or Oncology. For general questions not related to your own dog’s eligibility, please contact Dr. Steffey (530-752-3799, masteffey@ucdavis.edu).

Participation Requirements:

  • Dogs diagnosed with an oral tumor with owners that have elected to surgically remove the tumor
  • Ineligible: Dogs with pre-existing, palpably very large lymph nodes

Initial Evaluation for Participation: If you choose to enroll your dog, your dog will receive two CT scans on separate days: the first done for standard diagnostic/surgical planning, and the second done immediately prior to surgery. Both CT scans will be performed with contrast while under general anesthesia.

Procedures: If you choose to enroll your dog, your dog will receive two CT scans on separate days: the first done for standard diagnostic/surgical planning, and the second done immediately prior to surgery. Both CT scans will be performed with contrast while under general anesthesia.

Benefits: All costs associated with this study, including the second CT scan and the 1 hour of extra anesthesia time associated with each CT scans will be paid by the sponsor. Additionally, a financial benefit of $500 will be credited to your VMTH account after your dog completes the second CT scan on the day of his/her surgery.

Owner Responsibilities: If you allow your dog to participate in this study, you will be responsible for bringing your dog to the UC Davis VMTH for his/her scheduled appointments, covering costs associated with the standard diagnostic workup of your dog’s tumor, the first (diagnostic/surgical planning) CT scan, and standard costs associated with surgical removal of the oral tumor, and allowing him/her to be hospitalized for the required length of time pre- and postoperatively.

Printable Flyer (PDF)

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: 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)

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: Dr. Culp 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
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)

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: Dr. Culp 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.

Read about Sandy, a 6-month-old Labrador Retriever, that was helped by participating in this trial!

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 coordinator 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 UC Davis VMTH 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: Dr. Culp 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: Dr. Culp 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: Dr. Culp 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.

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

Printable Flyer (PDF)

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 coordinator to schedule an appointment with Dr. Michele Steffey. The coordinator 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 UC Davis VMTH 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 coordinator 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 UC Davis VMTH 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, you 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 coordinator 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.

If you cannot find what you are looking for, please email us or call (530) 752-5366.