Biomedical subjects
V B Reef
Publications and source records attributed to V B Reef.
Obstructive nephrolithiasis and ureterolithiasis associated with chronic renal failure in horses: eight cases (1981-1987).
Eight adult horses with obstructive nephrolithiasis and/or ureterolithiasis were examined between 1981 and 1987. One horse had bilateral ureteral obstruction at hospital admission; the others had unilateral ureteral obstruction. All horses had similar bilateral renal pathologic findings that were compatible with chronic intermittent or complete obstruction. Horses were referred for evaluation of weight loss, poor performance, and/or decreased appetite. Clinical findings, laboratory results, and/or postmortem findings in all horses supported the diagnosis of chronic renal failure. Age of the 8 horses varied between 2 and 17 years; 5 of the 8 were between 2 and 3 years old. Seven horses were Thoroughbreds and 1 was a Standardbred. Of the horses examined, 4 were females and 4 were males (2 geldings). Diagnosis of obstructive nephrolithiasis and/or ureterolithiasis was made in all of the hospitalized horses based on examination per rectum and/or renal ultrasonographic findings. Surgical removal of the obstructing calculi was performed in one horse. Although etiopathogenesis could not be proven, histopathologic findings in the kidneys of the horses of our study were suggestive of renal failure secondary to obstructive urinary disease.
Ultrasonographic findings in horses with cholelithiasis: eight cases (1985-1987).
Cholelithiasis and/or obstructive biliary tract disease was diagnosed ultrasonographically in 8 horses, 5 to 15 years old. Ultrasonographic findings revealed greater than normal amount of hepatic parenchyma in the right side of the abdomen in 8 horses and in the left side in 3 horses. The echogenicity of the liver was greater than normal, and thick distended bile ducts were seen in all horses. Choleliths were imaged ultrasonographically in 6 horses. Subsequently, postmortem findings in 6 horses revealed periportal and intralobular fibrosis, moderate bile duct dilatation, proliferation, and cholestasis. One or more choleliths were found in all horses. Ultrasonographic findings accurately depicted the histologic changes in the hepatic parenchyma in horses with cholelithiasis.
Pericarditis in horses: six cases (1982-1986).
Records of 6 horses with pericarditis were reviewed. Septic pericarditis was suspected in all horses, based on historic and clinical findings. In horses 1, 2, and 4, cytologic examination of the pericardial effusion revealed acute inflammation with severe neutrophil degeneration. In horses 3 and 5, cytologic examination of pericardial fluid revealed subacute inflammation with degenerated neutrophils, and in horse 6, chronic active inflammation, with well preserved neutrophils. In horses 1 and 3, bacteria were identified on cytologic examination of pericardial fluid. Results of microbiologic cultures of pericardial fluid were positive in horse 3. All horses were treated with broad-spectrum antibiotics. An indwelling pericardial catheter was used to lavage and directly administer antibiotics into the pericardial sac. Horses 1, 4, 5, and 6 survived, horse 2 died of unrelated causes, and horse 3 was euthanatized at the owner's request. Surviving horses returned to athletic performance.
Umbilical cord remnant abscess in a yearling colt.
An abscess of the external umbilical remnant and umbilical vein remnant was diagnosed in a 16-month-old colt, using ultrasonography. Because of the colt's size, primary closure of the surgical incision after umbilical cord resection was not complete. Vertical mattress stainless steel sutures and stents were used, and healing was by second intention. Intervening gas-filled viscera made it impossible to visualize ultrasonographically the bladder of umbilical artery remnants in a colt of this age.
Clinical, ultrasonographic, and surgical findings in foals with umbilical remnant infections.
Infection of umbilical arteries, umbilical vein, and/or urachus was diagnosed ultrasonographically in 33 foals 1 to 90 days old (mean, 17.7 +/- 17.3 days). In these foals, the most common initial problems were umbilical abnormalities, septic arthritis, and/or neonatal septicemia. In 16 foals, abnormalities of the external umbilical stalk were noticed on admission. Abnormalities of the internal umbilical structures were identified when enlargement and echogenic material (fluid and/or gas) were imaged ultrasonographically within these structures. Multiple structures were affected in 23 foals, with the urachus the most commonly affected structure. Surgical findings confirmed ultrasonographic identification of infected umbilical structures in 23 foals. Twenty-two samples from affected umbilical remnants submitted for culture at surgery were positive for bacterial growth. Multiple organisms were isolated in 15 cultures. Escherichia coli and beta-hemolytic streptococci were the most common isolates. Two foals died of late complications associated with surgical resection, 1 foal treated surgically and 3 foals treated medically died or were euthanatized because of other complications, and the remaining 27 foals lived.
Ultrasonographic diagnosis of small-intestinal intussusception in three foals.
Small-intestinal intussusceptions were diagnosed in 3 foals. Cross-sectional ultrasonography through the apex of the intussusceptum revealed a target-like pattern with a thick hypoechoic rim. The thick hypoechoic rim was caused by severe edema of the entering and returning walls of the intussusceptum. At the more proximal portion of the intestines, where parietal edema was less severe, the image appeared as 2 concentric rings and an inner circular area. The outer ring and inner circular area were hypoechoic and represented the returning and the entering wall of the intussusceptum. An additional cross-sectional pattern can be described as double concentric rings, with the inner lumen represented by a central echogenic core. Longitudinal scannings of the involved intestinal section revealed a different view of the same anatomic situation, with 2 hyperechoic areas delineated by 3 stripes of hypoechoic intestine. Ultrasonography of a foal's abdomen provides a clinician with a rapid noninvasive technique that may aid in the differential that may aid in the differential diagnosis of colic. The ultrasonographic diagnosis of intussusception may improve the recognition of a surgical lesion and improve the potential for successful treatment.
Cholelithiasis in horses: ten cases (1982-1986).
Ten horses with clinical signs consistent with cholelithiasis were evaluated. Fever, icterus, mild intermittent colic, and weight loss were reported. Clinical laboratory abnormalities included leukocytosis, hyper-proteinemia, and hyperfibrinogenemia. Gamma glutamyltransferase and liver isoenzyme of lactate dehydrogenase activities also were high. Choleliths were observed via ultrasonography of the liver in 5 of the 8 horses evaluated, and increased echogenicity of the hepatic parenchyma and dilated bile ducts were observed in all horses. Seven horses were treated medically, 5 of which died or were euthanatized. Three horses were treated surgically, of which only 1 survived. Cholelith composition varied, but cholesterol, calcium bilirubinate, and mixed bile pigments were most commonly observed.
Ultrasonography as a diagnostic aid in horses with anaerobic bacterial pleuropneumonia and/or pulmonary abscessation: 27 cases (1984-1986).
The medical records of 83 horses with pleuropneumonia and/or pulmonary abscessation, in which thoracic sonography was used, were reviewed. The sonograms of these horses were reviewed retrospectively for free gas echoes within pleural or abscess fluid. Anaerobic infection was confirmed in 27 horses, and gas echoes were observed in 21 horses. There was a significant (P less than 0.001) correlation between the observation of gas echoes and anaerobic infection in horses with pleuropneumonia and/or pulmonary abscessation. A foul odor to the breath or pleural fluid was significantly (P less than 0.001) associated with anaerobic infection. Poor survival rates were associated with gas echoes or a foul odor to the breath or pleural fluid, both of which were associated with anaerobic infection. Gas echoes within pleural or abscess fluid were found to be a sensitive and specific indicator of anaerobic infection, as was a putrid odor to the breath or pleural fluid. Evaluation for gas echoes and foul odor had better predictive value than did evaluation for gas echoes or foul odor alone. Gas echoes within pleural or abscess fluid is highly suggestive of anaerobic infection. Ultrasonography should be performed repeatedly in horses with pleuropneumonia to assess the progression or resolution of pleural and parenchymal disease. The detection of gas echoes on subsequent ultrasonograms may indicate the development of anaerobic infection.
Complications of a permanent transvenous pacing catheter in a horse.
Gross and histopathological findings in a 9-year-old horse implanted with permanent transvenous pacing cardiac catheters, 18 and 34 months before its death, are described. Lesions consisting of extensive fibrino-haemorrhagic thrombi with large numbers of bacterial colonies were present along the electrode wires and on mural and valvular endocardial surfaces of the right heart. There was a locally extensive area of suppurative endocarditis around the attachment site of the atrial electrode, which was loosely attached by a thin band of membranous tissue to the endocardium. The ventricular electrode was firmly embedded in the myocardium and was surrounded by a dense area of fibrous connective tissue in which multifocal mineralized areas were seen. Histologically, there was evidence of terminal bacteraemia. The observed lesions are discussed with respect to findings in man and other animals with similar cardiac implants.
Nephrolithiasis resulting in intermittent ureteral obstruction in a cow.
Bilateral nephrolithiasis with intermittent ureterolithiasis was diagnosed in a 7-year old Holstein cow. Two episodes of ureterolithiasis resulted in severe azotemia which resolved after spontaneous movement of the stone. A third episode of obstruction one year after the initial episode resulted in rupture of one kidney, necessitating euthanasia. The histopathological examination of the kidney was diagnostic for chronic pyelonephritis. Corynebacterium sp. was cultured from a nephrolith. In this case it is believed that the chronic pyelonephritis predisposed to the calculi formation.
Pulsed-wave Doppler evaluation of intracardiac blood flow in 30 clinically normal Standardbred horses.
Pulsed-wave Doppler echocardiography was performed on 30 clinically normal 1- to 6-year-old racing Standardbreds. There were 13 females, 13 geldings, and 4 stallions. Cardiac disease was not detected with M-mode, 2-dimensional real-time or pulsed-wave Doppler echocardiography. Normal flow velocities for right and left atrial outflow, right and left ventricular outflow, the aorta, and pulmonary artery were determined. Peak flow velocities for right and left atrial outflow occurred during the rapid filling phase and were higher toward the mitral valve (mean, 0.70 +/- 0.24 m/s) than toward the tricuspid valve (mean, 0.49 +/- 0.17 m/s). Peak flow velocities in the right and left ventricular outflow tracts were similar (means, 0.81 +/- 0.10 m/s and 0.75 +/- 0.39 m/s, respectively). Peak flow velocities in the pulmonary artery (mean, 1.09 +/- 0.42 m/s) and aorta (mean, 1.01 +/- 0.29 m/s) were similar, although flow peaked earlier in systole in the aorta than in the pulmonary artery.
Diagnosis and surgical correction of patent ductus venosus in a calf.
Patent ductus venosus was diagnosed in a 10-week-old Holstein heifer with acute onset of collapse and marked tenesmus. Additional clinical signs observed during the course of hospitalization included depression, anorexia, hind limb ataxia, bruxism, and poor growth. Clinicopathologic test results included high blood ammonia concentration, prolonged sulfobromophthalein half-life, and high serum bile acid concentration. Liver biopsy revealed mild periportal fibrosis, but no appreciable hepatocyte atrophy. Mesenteric portography and percutaneous ultrasonography confirmed the patent ductus venosus. An atrial septal defect prosthesis was placed in the ductus venosus, using a catheterization technique. After surgery, however, clinicopathologic test results were unchanged. Ultrasonography revealed that the prosthesis had pulled away from one side of the vessel. When the calf was 10.5 months old, surgical correction was achieved by a transhepatic ligation technique. Ultrasonography confirmed closure of the ductus venosus during and after surgery. Blood ammonia and serum bile acid concentrations and sulfobromophthalein half-life were normal 3 weeks after surgery. The calf had no further episodes of hepatoencephalopathy and was successfully bred at 18 months of age.
Treatment of bacterial endocarditis in a horse.
Using echocardiography, mitral valve bacterial endocarditis was diagnosed in a yearling Thoroughbred filly with a history of periodic fever and intermittent hind limb lameness. Streptococcus sp were isolated from blood, and the filly was treated with penicillin, resulting in a bacteriologic cure. Severe mitral regurgitation developed secondary to scarring of the valve, which resulted in the filly's death. A poor prognosis usually is indicated in horses with bacterial endocarditis, as bacteriologic cures are infrequent and severe valvular insufficiency often develops.
Ultrasonography of umbilical structures in clinically normal foals.
The umbilical arteries, urachus, and umbilical vein were scanned ultrasonographically in 13 clinically normal foals that ranged in age from 6 hours to 4 weeks. Sonograms were obtained using a 7.5-MHz sector scanner transducer placed across the midline of the ventral portion of the foal's abdominal wall. The umbilical vein was scanned from the umbilical stalk to its entrance into the hepatic parenchyma. The mean (+/- SD) diameter of the umbilical vein was 0.61 +/- 0.20 cm immediately cranial to the umbilical stalk, 0.52 +/- 0.19 cm midway between the umbilicus and liver, and 0.6 +/- 0.19 cm at the liver. The urachus and umbilical arteries were scanned from the umbilical stalk to the apex of the urinary bladder and had a mean total diameter of 1.75 +/- 0.37 cm at the bladder apex. The umbilical arteries also were scanned along either side of the bladder and had a mean diameter of 0.85 +/- 0.21 cm. These measurements and the ultrasonographic appearance of the internal umbilical structures from clinically normal foals can be used as references to diagnose abnormalities of the umbilical structures in neonatal foals.
Aortic valve insufficiency in a one-year-old colt.
Aortic insufficiency was suspected in a thin 1-year-old colt with a grade IV/V decrescendo holodiastolic murmur and a bounding arterial pulse. Echocardiographic findings (diastolic fluttering of the septal leaflet of the mitral valve, left ventricular volume overload, and incomplete aortic valve closure) were diagnostic for aortic valve insufficiency. Moderately thick fibrotic aortic valve leaflets were found at necropsy. Fenestrations were found in the aortic and pulmonic valve cusps. Congenital valvular disease may have led to aortic valvular insufficiency in this horse.
Conservative treatment of a minimally displaced fracture of the radius of a horse.
The successful conservative treatment of an open, displaced fracture of the radius of a horse suggests that conservative treatment should not be ignored when surgery is not an option. The importance of proper soft-tissue management and the use of broad-spectrum antimicrobial treatment in the management of orthopedic injuries is emphasized.
Mitral valvular insufficiency associated with ruptured chordae tendineae in three foals.
Mitral valvular insufficiency associated with ruptured chordae tendineae was diagnosed in 3 foals with signs of congestive heart failure, which were believed to be secondary to the development of pulmonary hypertension associated with the valvular insufficiency. The septal leaflet of the mitral valve was affected in all 3 foals, and foal 2 also had ruptured chordae tendineae associated with the caudal mitral valve leaflet. Bacterial endocarditis and myocardial necrosis were associated with the ruptured chordae tendineae in foals 3 and 2, respectively. Idiopathic rupture was considered in foal 1. Two-dimensional echocardiography demonstrated a flail mitral valve leaflet in foals 2 and 3 and a ruptured chorda tendineae in foal 3. The ruptured chorda tendineae in foal 1 was not visualized with M-mode echocardiography.