PubMed Health⌕ Search

Biomedical subjects

M B Mahaffey

Publications and source records attributed to M B Mahaffey.

At least 19 recordsLinked to original sources

Evaluation of colposuspension for treatment of incontinence in spayed female dogs.

OBJECTIVE: To determine the long-term effects of colposuspension in spayed female dogs with urinary incontinence and identify preoperative anatomic or urodynamic measurements associated with a successful outcome. DESIGN: Prospective study. ANIMALS: 23 client-owned spayed female dogs with urinary incontinence. PROCEDURE: Prior to surgery, a history was obtained, and a physical examination, CBC, serum biochemical analyses, urinalysis, bacterial culture of a urine sample, vaginourethrocystography, urethral pressure profilometry, and leak point pressure test were performed. Colposuspension was performed, and preoperative tests were repeated 2 months after surgery. Clients were interviewed 2 weeks, 1 month, and 1 year after surgery. RESULTS: 22 dogs were followed up for 1 year. Twelve had complete urinary control 2 months after surgery, and 3 had complete urinary control 1 year after surgery. Dogs with normal urinary control at 2 months had an increased leak point pressure (LPP), compared with preoperative measurements, and their LPP was the same as normal dogs. Eight dogs had complete urinary control, and 9 were considered greatly improved 1 year after surgery when medical treatment was added to the effect of colposuspension. Client satisfaction was high, with 19 of 22 (86%) owners being pleased with their decision to have surgery performed. The only predictors of complete urinary control 2 months after surgery were a more caudal position of the external urethral opening in relation to the pubis on preoperative radiographs and a longer overall urethral length. CONCLUSIONS AND CLINICAL RELEVANCE: Colposuspension alone will result in complete urinary control in few dogs with urinary incontinence but may improve urinary control sufficiently that owners will be pleased. Preoperative vaginourethrocystography may be helpful in predicting response to surgery, and the LPP test correlates with improved urinary control.

Animals↗

A rapid and strong laparoscopic-assisted gastropexy in dogs.

OBJECTIVE: To develop a technique for laparoscopic gastropexy in dogs and evaluate effects on stomach position and strength of the adhesion between the stomach and abdominal wall. ANIMALS: 8 healthy dogs. PROCEDURE: Dogs were anesthetized, and the abdomen was insufflated with carbon dioxide. A laparoscope was placed through a cannula inserted on the abdominal midline caudal to the umbilicus. Babcock forceps placed through a cannula inserted lateral to the right margin of the rectus abdominus muscle were used to exteriorize the pyloric antrum, a longitudinal incision was made through the serosa and muscular layer of the pyloric antrum, and the seromuscular layer of the pyloric antrum was sutured to the transversus abdominus muscle. After surgery, positive-contrast gastrography was used to evaluate stomach position and the onset of gastric emptying, and ultrasonography was used to assess stomach wall activity and mobility. Dogs were euthanatized 1 month after surgery, and tensile strength of the adhesion was tested. RESULTS: In all dogs, stomach position and the onset of gastric emptying were normal 25 days after surgery, and the pyloric antrum was firmly attached to the abdominal wall 30 days after surgery. Mean +/- SD ultimate load of the adhesion in tension was 106.5 +/- 45.6 N. CONCLUSIONS AND CLINICAL RELEVANCE: The laparoscopic gastropexy technique described in the present study could be performed quickly and easily by an experienced surgeon, resulted in a strong fibrous adhesion between the stomach and abdominal wall, and appeared to cause minimal stress to the dogs.

Abdominal Muscles↗

Immediate urodynamic and anatomic response to colposuspension in female Beagles.

OBJECTIVE: To characterize urodynamic function and anatomy before and after colposuspension in anesthetized female Beagles. ANIMALS: 12 adult female Beagles. PROCEDURE; During general anesthesia (thiopental sodium induction and halothane maintenance), urethral pressure profiles, leak point pressure measurements with a 50-ml bladder volume, positive contrast cystograms, and retrograde vaginourethrocystograms were performed. A caudal midline laparotomy was used to perform colposuspension. Urodynamic and radiographic studies were repeated after surgery. RESULTS: Leak point pressures were increased (120 to 168.9 cm H2O), and maximum urethral closure pressures decreased (43.7 to 19.3 cm H2O ) after colposuspension. The urethra and bladder were moved cranially; the external urethral orifice was positioned closer to the pelvic cavity, and the neck of the bladder was positioned more cranially into the abdomen. Length of the urethra, as measured by use of vaginourethrocystograms, was increased by 3%. As measured by use of urethral pressure profiles, total profile length was increased by 19.9%, and functional profile length was increased by 19.2%. CONCLUSIONS AND CLINICAL RELEVANCE: Increased leak-point pressure correlated with the expected clinical improvement attributable to colposuspension. Increased exposure of the urethra to abdominal and pelvic cavity pressures may be the mechanism by which incontinent dogs become continent after colposuspension. Results of the leak-point pressure test may correlate with clinical behavior before and after colposuspension for treatment of incontinence.

Anesthesia, General↗

Use of partial prostatectomy for treatment of prostatic abscesses and cysts in dogs.

OBJECTIVE: To determine whether dogs had prostatic disease, urinary incontinence, or urinary tract infection 1 year after partial prostatectomy to treat prostatic abscesses and cysts. DESIGN: Prospective study. ANIMALS: 20 male dogs with prostatic abscesses or cysts. Fifteen dogs had evidence of urinary tract infection. Only 8 dogs urinated normally; the remainder dribbled, had obstructions, or required medical treatment. PROCEDURE: Partial prostatectomy was performed on each dog. Sexually intact dogs (n = 12) also were castrated. RESULTS: None of the dogs had return of prostatic cystic enlargement or clinical signs of prostatic disease during the first year after surgery. Two dogs were euthanatized within 1 year after surgery, with 1 dog having prostatic enlargement and adenocarcinoma and 1 dog having unrelated lymphosarcoma. Fifteen dogs were continent. The remaining 5 dogs urinated normally but had intermittent and minor incontinence. Eleven dogs had no signs of infection 1 year after surgery, 5 had pyuria or positive urine bacteriologic culture results, 2 did not have urinalysis performed, and 2 were euthanatized. CLINICAL IMPLICATIONS: Dogs with severe prostatic abscesses or cysts and infections can be successfully treated by partial prostatectomy with an ultrasonic surgical aspirator and castration, resulting in long-term disease resolution. Although most dogs with severe prostatic disease do not urinate normally before surgery, nearly all dogs resume normal micturition after partial prostatectomy. Postoperative results of partial prostatectomy appear to be better than those of previous drainage techniques for treatment of prostatic cavitary disease.

Abscess↗

Use of hepatobiliary scintigraphy in clinically normal cats.

Hepatobiliary scintigraphy provides a noninvasive assessment of hepatobiliary structure and function, and has been used extensively in people. Hepatocellular measurements determined in the cats of this study include cardiac washout (< or = 2 minutes) and time of maximal hepatic activity (< or = 5 minutes) and hepatic washout (< or = 30 minutes). The gallbladder response to synthetic cholecystokinin was determined to be < or = 3 minutes. Additional measurements also were identified. Potential use of hepatobiliary scintigraphy in feline medicine is discussed.

Animals↗

Ultrasonography of the umbilical structures in clinically normal calves.

The umbilical stalk, vein, and arteries, urachal region, and urinary bladder of 9 healthy Holstein calves were scanned ultrasonographically at weekly intervals from 1 day to 3 weeks of age. Four additional calves of representative ages, 1 day, 1 week, 2 weeks, and 3 weeks were euthanatized after ultrasonographic evaluation of the umbilical structures. Umbilical structures from these 4 calves were dissected, photographed, and examined histologically to ensure normalcy. These gross specimens were correlated with the ultrasonographic images and compared with serial ultrasonograms of 9 calves. The ultrasonographic scanning technique and the appearance of normal umbilical stalk, arteries, and vein, and urachus in calves were different from those described for foals. The umbilical vein of calves was scanned from the umbilical stalk to the liver along the right abdominal wall. Two veins, which merged within the body wall, were identified within the stalk. Umbilical arteries were not found within the umbilical stalk; they ended abruptly near the apex of the urinary bladder. A urachal remnant was not identified in any of the calves. A range of normal values for measurement of the umbilical stalk, umbilical arteries, and umbilical vein at 3 sites was determined. The described ultrasonographic appearance and measurements of the normal Holstein calf umbilicus may be used as a reference for evaluation of calves with internal umbilical abnormalities.

Age Factors↗

Ultrasonographic appearance of the ovaries of dogs during the follicular and luteal phases of the estrous cycle.

Ultrasonography of the ovaries of 10 bitches was performed daily, using a 7.5-Mhz transducer with a built-in stand-off pad, from the onset of proestrus until the onset of metestrus. Ovarian size, shape, location, echogenicity, follicular development, and apparent ovulation were monitored. Blood samples were collected twice daily for luteinizing hormone determination and daily for progesterone determination. Vaginal smears were made daily for cytologic evaluation. Ultrasonograms were evaluated independent of hormonal and cytologic data, and the day of ovulation was noted. Initially, the ovaries were uniform and had an echogenicity that was equal to or slightly greater than that of the renal cortex. Follicles appeared as focal hypoechoic to anechoic rounded structures. Ovaries were easier to identify as follicular development progressed. Ovarian size increased with time. Apparent ovulation was characterized by a decrease in number of follicles seen from 1 day to the next, but 1 or more follicles remained in at least 1 ovary of 7 of 10 bitches. The ovaries had an oval shape that became rounded after ovulation. At some time after ovulation, all bitches had cystic (anechoic) structures indistinguishable from follicles. These structures increased in echogenicity and decreased in size with time and may have been follicles that did not ovulate, corpora hemorrhagica, fluid-filled corpora lutea, or cystic luteinized follicles. Time of ovulation determined by ultrasonography paralleled that predicted on the basis of hormonal data in 9 of 10 bitches and with cytologic findings in all bitches.

Animals↗

Megaesophagus in two cats.

Megaesophagus was diagnosed in 2 cats. Both had a history of regurgitation, and one was dyspneic. Radiography of the thorax and abdomen revealed generalized megaesophagus and gastric distention with gas. There was no esophageal motility during fluoroscopic observation. The prognosis for cats with megaesophagus is guarded. Although they may be satisfactory pets, cats with this condition should not be used for breeding because the condition is believed to be inherited through recessive genes.

Animals↗

Serum prolactin and growth hormone responses to naloxone and intracerebral ventricle morphine administration in heifers.

These studies examined responses of serum prolactin (PRL) and growth hormone (GH) to opioid agonist and antagonist administration in heifers. To minimize nonspecific and behavioral effects and to facilitate future studies with specific opioid receptor agonists, a cannula was placed within the third cerebral ventricle of the brain of 4- to 10-mo-old heifers to directly access hypothalamic regions involved in the regulation of PRL and GH secretion. Increasing doses of morphine (M) from 2 to 1,500 micrograms injected into the third cerebral ventricle increased (P less than .001) serum PRL concentrations in a dose-related manner. Growth hormone responses were variable, resulting in elevated (P less than .05) serum concentrations following morphine, but no dose-related effects were apparent. Both PRL and GH responses to 700 micrograms M were absent when an intracerebral ventricle injection of an equimolar dose of naloxone, an opioid receptor antagonist, was administered prior to M. In a replicated 4 x 4 latin square, the effects of intravenous naloxone on PRL and GH responses was tested in young (86 +/- 11 d) and older (234 +/- 6 d) heifers. Naloxone at doses of 1, 2 and 4 mg/kg reduced (P less than .05) serum concentrations of PRL for 45 to 60 min. Mean concentrations of GH tended to be higher (P less than .07) in older heifers All doses of naloxone decreased (P less than .05) serum GH concentrations in older heifers but proved ineffective in younger heifers. There were no differences between doses of naloxone on either PRL or GH. These data suggest that endogenous opioids are involved in the regulation of PRL and GH secretion in heifers.

Animals↗

Segmental hemiatrophy in a dog.

Congenital asymmetric development, resulting in a small right thoracic limb, was diagnosed in a dog. The limb was anatomically normal. The lesion closely resembled hemiatrophy. Congenital asymmetric development should be considered in the differential diagnosis of limb length discrepancies. Treatment is required only in cases of extreme discrepancy between the normal and affected limb.

Animals↗

Free chondral fragment involving the lateral trochlear ridge of the talus in a dog.

A saucer-shaped defect involving the lateral trochlear ridge of the talus and a radiopaque joint fragment were evident on radiographs of the left tarsus in a 6-month-old Rottweiler. Surgical treatment involved removal of the joint fragment and debridement of the defect. Histologic interpretation of the specimen was a chondral fragment. It is important to realize the possibility of a lesion in the location described, as this may be an additional site for osteochondrosis dissecans of the canine tarsus.

Animals↗

Pelvic bladder in dogs without urinary incontinence.

Double-contrast cystography was performed simultaneously with cystometrography in 6 male and 6 female dogs. All dogs were continent, and results of urinalyses were normal. Initial radiographs were made following intravesical infusion of 0.88 ml of positive contrast medium/kg of body weight. Additional radiographs were made during infusion of CO2. The last radiographs were made at the time of detrusor reflex (11 dogs) or when intravesical pressure reached 50 cm H2O (1 female). An average of 34% (range, 11% to 67%) of bladder length was within the pelvic canal when only the positive contrast medium was infused into the bladders. By the end of CO2 infusion, the bladder neck was more cranially located in 5 of 6 males and in 5 of 6 females. On the last radiographs made, an average of 19% (range, 10% to 35%) of bladder length was within the pelvic canal in 3 of 6 males and in 4 of 6 females. The bladder neck was rounded in 10 of 12 dogs. Thus, it was concluded that previous reports associating pelvic urinary bladder with urinary incontinence and other urologic abnormalities are questionable.

Animals↗

Cystometry in dogs under oxymorphone and acepromazine restraint.

Cystometry was performed in 12 dogs under oxymorphone and acepromazine restraint. A detrusor reflex occurred in 10 of 12 dogs (83%). Mean threshold pressure and volume were 31 cm H2O and 22 ml/kg, respectively. Tonus limb II varied inversely with threshold volume. Threshold volume varied directly with body weight; threshold pressure was independent of body weight.

Acepromazine↗

Congenital portacaval shunts in two cats: diagnosis and surgical correction.

Congenital portacaval shunts causing signs of hepatic encephalopathy were diagnosed and surgically corrected in 2 cats. A tentative diagnosis of portacaval shunt in each case was based on history, results of physical examination, and a high venous ammonia concentration. A definitive diagnosis was established by mesenteric portography and by direct visualization of the shunt vessel during surgery.

Animals↗

Kinetics of gentamicin after intravenous, intramuscular, and intratracheal administration in sheep.

Kinetics of gentamicin (2.2 mg/kg of body weight) were investigated in 7 sheep after IV bolus administration. The mean serum concentration profile could be described by a 2-compartment open model with a distribution rate constant (alpha) of 3.112 +/- 1.681 hour-1 [half-life, t1/2(alpha) = 17.22 +/- 8.63 minutes] and an overall elimination rate constant (beta) of 0.485 +/- 0.028 hour-1 [t1/2(beta) - 85.87 +/- 5.03 minutes]. The apparent volume of distribution was somewhat restricted [Vd(area) = 0.194 +/- 0.059 L/Kg], and the total body clearance was 1.559 +/- 0.400 ml/kg/min. Equal dosages of gentamicin (2.2 mg/kg) were also given IM and intratracheally (IT). after IM injection, gentamicin reached peak serum concentration at postinjection minutes (PIM) 45, surpassing concentrations after the IV injection for the remainder of the experiment. The IT injection produced detectable serum concentrations at PIM 5, with a peak concentration at PIM 60. The serum drug concentrations after IT injections remained well below concentrations after IV and IM injections. Radiographic analysis of an IT injection of a gentamicin-tantalum suspension revealed good distribution throughout the trachea and proximal bronchi, with physical clearance of the tantalum occurring after greater than or equal to 10 minutes. Aspiration biopsy of the tracheal wash 6 hours after IT gentamicin injection revealed no cytologic response to gentamicin in 6 of 7 sheep, with the single response that of a purulent exudate.

Animals↗

Focal loss of pigment in the Belgian Tervuren dog.

Hypopigmentation most commonly affecting the face and mouth of the Belgian Tervuren dog was characterized by an absence of melanocytes in the epidermis. Pigment loss usually occurred during young adulthood, and although there was partial repigmentation in some dogs, complete repigmentation did not occur. Treatment with vitamin and mineral supplements was unrewarding. The condition appeared to have some degree of heritability and to be similar to vitiligo in man.

Adrenocorticotropic Hormone↗