Cat & Dog Imaging: Interventional Radiology, Endourology, & Endoscopy
At Atlantic Veterinary Internal Medicine & Oncology, we offer advanced, minimally-invasive procedures for the diagnosis and treatment of various conditions of the respiratory system, gastrointestinal tract, and urinary tract. Our specialists can provide many different imaging options combined with non-invasive procedures which are safe, effective and can provide treatment alternatives to more surgeries.
Indications for Interventional Endourology
Endourology involves using minimally-invasive techniques to study the urinary tract and perform safe and effective procedures to alleviate various obstructions by placement of stents, removal of polyps and stones from the bladder as well as other advanced endourologic techniques.
Abnormal narrowing or malignant obstruction of the urethra can result in a urological emergency. With the aid of fluoroscopy, we can perform a safe, effective, and minimally-invasive procedure to place urethral stents to expand the urethra and re-establish normal urine flow.
For benign narrowing, we may recommend fluoroscopy-guided ballooning and the placement of temporary stents. For dogs and cats with malignancy of the urethra, we recommend a more permanent stent.
Bladder stones are encountered in our daily practices. Surgery is often used for the removal of the bladder stones. However, it does entail an abdominal incision with associated morbidities. Instead, we recommend less invasive methods such as cystoscopy-guided stone removal. If the stones are too large for cystoscopy removal or too numerous, a newer, less invasive alternative is now available for select cases and clients.
PCCL is a minimally invasive procedure where we make a small abdominal incision to expose the apex of the bladder and place a trocar via incision into the bladder wall. We pass a cystoscope through the cannula into the bladder lumen, which allows us to fully visualize the area within, along with the entire urethra in females (and most males). We then remove the stones via the cannula assembly. At AVIM&O, we can help you decide whether PCCL is a good alternative to surgery for your pet.
Inflammatory polyps, hemangioma, and focal neoplasia of the bladder can be associated with significant bleeding, recurrence of lower urinary tract signs and infections. Surgery is typically recommended to remove these lesions. However at AVIM&O, we recommend performing minimally invasive cystoscopy-guided laser ablation of such lesions which is both safe and effective.
A weak urethral sphincter is a common problem in dogs, and often a major reason for ongoing care (and frustration on the part of the owner). Medical therapy can help reduce the incontinence, but it may ultimately fail. To more effectively “strengthen” the urethra and reduce incontinence, we offer a safe and effective cytoscopy-assisted collagen injection. In more severe incontinence cases, we can surgically place a hydraulic occluder, which can provide considerable improvement. We can answer your questions about this technique and whether it is appropriate for your pet.
Ectopic ureter is a common cause of urinary incontinence in young female dogs, but it can also affect male dogs. This condition causes the ureter to terminate not at the urinary bladder, where it should, but at a different site, such as the urethra.
The preferred method for treating this congenital problem is cystoscopy-assisted laser ablation. After the ectopic ureter has been confirmed, we use a diode laser to “relocate” the ureteral opening into the bladder lumen. In male dogs, we use a percutaneous perineal approach to access the urethra to perform the same procedure as in female dogs. AVIM&O is equipped with a state-of-the-art diode laser system for use through the cystoscope working channel. This advanced technique allows us to avoid more invasive surgeries and their associated morbidities.
Ureteral obstructions can be caused by stones, blood clots, pus, strictures, or tumors. Left untreated, this can lead to rapid and irreversible decline in kidney function. The best method for treating dogs with ureteral obstruction is cystoscopy-guided placement of ureteral stents. We can place these stents non-invasively, quickly and safely, providing patients with immediate relief. In cats, we recommend surgically placing a subcutaneous ureteral bypass (SUB) device.
Idiopathic renal hematuria is an uncommon disease in which an animal bleeds from one or both kidneys causing the urine to become very bloody. The cause of the blood loss is not known. Surgery to remove the bleeding kidney is not recommended not only because the other kidney may also start bleeding at a later time, but also because one would be removing a completely normal functioning kidney.
Recently, sclerotherapy has been used to cauterize the bleeding kidney(s) identified via endouroscopic techniques. Using a cystoscope, the sclerotherapy agent is delivered directly into the pelvis of the affected kidney(s) to stop the bleeding.
Indications for Interventional Radiology
AVIM&O uses its advanced cat and dog imaging equipment including fluoroscopy, CT scan, and tracheobronchoscopy to help diagnose and treat the following conditions:
Tracheal collapse is a common, progressive, degenerative disease. It is often the result of cartilage hypocellularity (decrease in number of cartilage cells present), leading to subsequent dynamic airflow collapse while the patient is breathing. This condition may also be associated with a lax dorsal tracheal membrane, resulting in obstruction, coughing, and potentially severe dyspnea.
Intraluminal tracheal stenting is a minimally invasive procedure we can use to reestablish patency (opening) of a narrowed tracheal lumen. Tracheal narrowing is most commonly seen secondary to tracheal collapse in patients, but it has also been seen with tracheal neoplasia and benign tracheal stricture.
If a tumor or polyp is obstructing the trachea or lower airways, we can offer tracheobronchoscopy as a minimally invasive solution for dogs and cats. With our electrocautery or diode laser, we can significantly reduce the size of the inflammatory polyp or tracheal tumor, resulting in significant improvement of the patient’s respiratory distress. We can also retrieve foreign material using various forceps or snares.
Patients with nasopharyngeal stenosis have trouble breathing due to scarring or malformation of the back of the nasal passage. This may occur after a severe infection, or it may be the result of regurgitation under anesthesia. The best treatment option for affected dogs and cats is a combination of balloon dilation to open up the region, followed by placement of a nasopharyngeal stent. We often use different medical imaging modalities including CT images, fluoroscopy, and endoscopy to assess the lesion, widen the space and place a stent. We use retrievable stents that we can remove after they have been in place for a few weeks or even months. Nasopharyngeal stents will hold the affected passage open and make the patient much more comfortable.
Deep-seated pulmonary (lung) lesions can be difficult to visualize on ultrasound due to the ultrasound-air interface. Our interventional radiology service offers a new technique using fluoroscopy to obtain samples for those hard-to-reach pulmonary nodules. This technique is safe and effective in obtaining diagnostic samples in both dogs and cats. Sampling pulmonary lesions is an important step prior to recommending more invasive procedures, such as surgery of the chest cavity.
Interventional Gastrointestinal Endoscopy
The specialists of AVIM&O can help to treat dogs and cats suffering from a myriad of gastrointestinal issues, including narrowing of the esophagus or colon, and the presence of inflammatory polyps and/or tumors.
Difficulty swallowing due to benign esophageal strictures (abnormal narrowing or tightening of the esophagus) is an important cause of morbidity and mortality in dogs and cats. Esophagitis (inflammation of the esophagus) due to gastro-esophageal reflux during anesthesia is often the cause for development of esophageal stricture. However, any mechanical (eg. foreign body) or chemical injuries to the esophageal mucosa can lead to inflammation of the esophagus as well as stricture.
Balloon dilation or bougienage are most currently used to widen a narrowed esophagus. Unfortunately, such procedures need to be repeated several times with only partial improvement in the clinical signs. At AVIM&O, we recommend a one-stage esophageal balloon dilation, which appears to be a very effective, single-procedure alternative to repeated balloon dilation.
Colonic stricture, or abnormal narrowing of the colon or rectum, can be caused by injury of the intestinal wall from foreign bodies or trauma, inflammatory disease (perianal fistula disease, inflammatory bowel disease, and anal sacculitis), or neoplasia. Benign strictures can be treated with balloon dilation +/- a colonic stent. Rectal stenting may also be used for recurrent or malignant strictures if surgical resection is not an option.
Inflammatory polyps or tumors of the rectum/colon are uncommon, but they can be associated with significant clinical signs including blood in the stool, straining to defecate, and constipation. We often recommend surgery when the lesions are relatively close to the anus. However, when located deeper in the rectum, surgical removal becomes more invasive and associated with greater morbidity. At AVIM&O, we can use a combination of electrocautery and endoscopy to remove or debulk inflammatory polyps or tumors.