Clinical techniques in small animal practice最新文献

Cats are usually presented at a very late stage in the course of glaucoma when the eye is already blind. Secondary glaucoma because of another underlying ocular lesion is the most common form of glaucoma in the cat and is frequently associated with chronic anterior uveitis or intraocular neoplasia. Chronic stages of glaucoma in the cat are characterized by buphthalmus, anterior lens luxation, and exposure keratitis secondary to the enlarged globe. Ophthalmoscopic signs of glaucomatous retinal degeneration are only noticed in very advanced stages. Treatment of glaucoma in cats is usually aimed to keep the eye comfortable and within a normal intraocular pressure range. However, many antiglaucoma medications that are successfully used in humans and dogs are not very well tolerated by cats and, therefore, the selection of recommended drugs is limited in this species.

Clinical evaluation of early renal dysfunction is problematic in the nonazotemic animal. Measurement of glomerular filtration rate (GFR) provides the most accurate assessment of renal function. However, many methods of determining GFR are not practical for use in routine veterinary practice. This article provides a description and literature review of methods to determine GFR, including benefits and drawbacks of each method for the practicing veterinarian.

Urodynamic testing provides a quantitative assessment of the function of the small animal lower urinary tract. Most commonly these techniques are utilized to assess urethral tone (urethral pressure profile or UPP) and bladder detrusor muscle function (cystometrogram or CMG). A UPP may be indicated in cases of canine and feline micturition disorders. Examples include suspected primary sphincter mechanism incontinence (PSMI), ureteral ectopia, other congenital abnormalities, suspected neurological disorders, and mechanical or functional urethral obstruction. A UPP can be performed effectively utilizing human dedicated equipment. A CMG may be indicated to assess detrusor function in all of the above cases as well as cases of suspected atonic or infiltrated urinary bladder. This procedure can also be performed using the same human equipment. These tests are useful not only in providing an accurate diagnosis, but also in providing a sensitive prognostic indicator for clinical outcome of micturition disorders with and without pharmacological or surgical therapy. A leak pressure point may also be established in dogs with urinary incontinence, and may be even more sensitive than a UPP to predict clinical incontinence in some cases.

The urinalysis is an essential part of the diagnostic evaluation for all urinary and many metabolic diseases. Its assessment includes evaluation of physical characteristics (color, clarity, and volume), biochemical parameters (urine pH, blood, glucose, ketones, bilirubin, urobilinogen, and protein) and microscopic sediment evaluation (RBC, WBC, organisms, epithelial cells, crystals, and casts). Many of these parameters are influenced by collection method and therefore, it is essential to interpret accordingly. Knowledge of factors that can interfere with the accuracy of some test results can decrease improper interpretation. When all of these parameters are evaluated in combination with clinical signs, physical examination, thorough history and other laboratory tests, a diagnosis will often be attained.

Hypertension is a common sequela to renal disease in cats and dogs, affecting as many as 61% cats and 93% of dogs, respectively. Undiagnosed and untreated, elevations in blood pressure can have deleterious effects on the brain and heart as well as promote further renal injury. In this article, we discuss the identification of patients at risk for hypertension as well as methods for measuring blood pressure and the treatment of hypertensive patients.

Cystoscopy is a powerful tool for characterization of lower urinary tract disease in dogs and cats. Current applications of cystoscopy include diagnostic and interventional techniques. This article reviews cystoscopy equipment, procedures, and common applications of cystoscopy. A review of normal anatomy and common lower urinary tract lesions identifiable with cystoscopy is also presented.

Renal diseases are common in dogs and cats. Renal biopsy may be required during the evaluation of the patient to establish a definitive diagnosis, determine the severity of the lesion and formulate an optimal treatment plan. Renal biopsy specimens can be collected via several methods. Percutaneous techniques are performed with ultrasound guidance in both dogs and cats or blindly in cats. If ultrasound guidance is not available, the keyhole technique can be used in dogs. Biopsy can also be performed using laparoscopy or surgery. While complications can arise with any of these techniques, complications are less frequent when an experienced operator uses proper technique. Renal biopsy specimens must be processed and evaluated appropriately if consistent and accurate diagnoses are to be rendered. The article summarizes patient selection and evaluation, renal biopsy techniques, expected complications of renal biopsy, and appropriate processing and evaluation of the renal biopsy specimen.

Excretory urography is a type of contrast study used to verify and localize upper urinary tract disease. In some instances, information regarding renal function and disease pathophysiology can also be obtained. With the recent advances in small animal ultrasonagraphy, excretory urography has become an underutilized procedure. This article will help explain why excretory urography remains, and will remain, a ubiquitous test that gives excellent detail of the entire urinary tract, and remains an essential tool for the assessment of the renal pelves and especially the ureters. Specifically, this article will focus on technique and interpretation of a properly performed excretory urogram.

Cystography is a radiographic study performed to aid in evaluation of the urinary bladder for extramural, mural, or intraluminal lesions. These lesions may primarily involve the urinary bladder or may be an extension of disease from adjacent organs. Cystography is easy to perform with relatively few complications. Different types of cystography (positive versus negative contrast) may be used depending on the type of information that the clinician hopes to obtain. Although a valuable technique, it is important to correlate the findings on cystography with other clinical information to arrive at the final diagnosis.