URETEROLITHIASIS AND PAPILLOMA FORMATION IN THE URETER OF A GUINEA PIG

A 5-year-old guinea pig with suspected urolithiasis was presented for radiology and ultrasound examinations of the abdomen. Radiographically, an irregular-shaped mineral opacity was detected in the area of the urinary bladder. Ultrasonographically, pyelectasia of the right kidney, hydroureter with an ureterolith cranial to a thickened ureter wall close to the ureterovesical junction, and a thickened urinary bladder wall were detected. Histopathologically, the thickened ureter wall was found to be a papilloma. The ureter calculus consisted of 100% calcite.     

Long-term outcome of domestic ferrets treated surgically for hyperadrenocorticism: 130 cases (1995-2004)

OBJECTIVE: To determine the long-term survival rate and factors that affect survival time of domestic ferrets treated surgically for hyperadrenocorticism. STUDY DESIGN: Retrospective case series. ANIMALS: 130 ferrets with hyperadrenocorticism that were treated surgically. PROCEDURES: Medical records of ferrets surgically treated for hyperadrenocorticism were reviewed. Data recorded included signalment, duration of clinical signs prior to hospital admission, CBC values, serum biochemical analysis results, anesthetic time, surgical time, concurrent diseases, adrenal gland affected (right, left, or both [bilateral]), histopathologic diagnosis, surgical procedure, caudal vena caval involvement (yes or no), postoperative melena (yes or no), days in hospital after surgery, and whether clinical signs of hyperadrenocorticism developed after surgery. RESULTS: 130 ferrets were entered in the study (11 of 130 ferrets were admitted and underwent surgery twice). The 1- and 2-year survival rates were 98% and 88%, respectively. A 50% survival rate was never reached. Combined partial adrenal gland resection with cryosurgery had a significantly negative effect on survival time. No other risk factors were identified. Survival time was not significantly affected by either histopathologic diagnosis or specific affected adrenal gland (right, left, or bilateral). CONCLUSIONS AND CLINICAL RELEVANCE: Ferrets with adrenal gland masses that were treated surgically had a good prognosis. Survival time of ferrets with hyperadrenocorticism undergoing surgery was not affected by the histologic characteristic of the tumor, the adrenal glands affected (right, left, or bilateral), or complete versus partial adrenal gland resection. Debulking was a sufficient surgical technique to allow a favorable long-term outcome when complete excision was not possible.     

Ultrasonographic evaluation of the adrenal glands in healthy dogs: repeatability, reproducibility, observer-dependent variability, and the effect of bodyweight, age and sex

Adrenal length and width were determined from two-dimensional ultrasound longitudinal images. In study 1, 540 measurements of adrenal glands were attempted from five healthy beagle dogs by three different observers with different levels of expertise in ultrasonography, to determine the variability of adrenal gland measurements. Of these, 484 measurements were included in the statistical analysis, since 16 measurements of the left adrenal gland and 40 for the right could not be visualised by the observer. In study 2, a single measurement of both adrenal glands was taken from each of 146 dogs by the most trained observer from study 1, and the effects of different health status (healthy dogs v dogs with non-adrenal diseases), bodyweight, age and sex were assessed. A total of 267 measurements were included in the statistical analysis. The lowest intra- and inter-day coefficient of variation values were observed for the left adrenal gland and by the most trained observer. The health status had no statistically significant effect on adrenal gland length or width, whereas age had a significant effect only for the left adrenal gland (the greater the age, the greater the width or length) and sex had a significant effect only for the right adrenal gland (the width was larger in males and the length larger in females). The bodyweight had a significant effect for the length of both adrenal glands (the greater the bodyweight, the greater the length), but not the width. The differences between sd and coefficient of variation values for the width of the left adrenal gland were not statistically significant between the three observers, whereas they were statistically significant for the right adrenal gland.     

MAGNETIC RESONANCE IMAGING OF THE PRESUMED NORMAL CANINE ADRENAL GLANDS

Forty-three dogs without evidence of endocrine disease that underwent spinal or abdominal magnetic resonance imaging (MRI) for clinical reasons were studied. Because the procedures were not optimized for inclusion of the adrenal glands, they were not always visible in all planes. Eighty-five of the 86 adrenal glands were seen and only the left gland in a 6-month-old Irish wolfhound could not be found. The right adrenal gland lay cranial to the left in all of the animals in which both glands were seen. The best landmarks for localization of the glands were vascular; both adrenal glands were always cranial to the ipsilateral renal vessels and in the region of the celiac and cranial mesenteric arteries. Various measurements were made on all the available scan planes. In some dogs the whole adrenal gland was difficult to visualize clearly, and this hindered the measuring process, especially when the right adrenal gland was in close contact with the caudal vena cava. The adrenal glands were mainly linear in shape but also had a variable degree of modification of their poles, especially the cranial pole of the right adrenal gland, which tended to be consistently wider and to present different shapes (rounded, arrowhead, inverted P, hook-shaped, triangular, or dome-shaped). Two main patterns of signal intensity were seen on fast spin echo (FSE) sequences (T2-weighted, T1-weighted, and T1-weighted after administration of a paramagnetic contrast medium): homogeneous and hypointense to surroundings or a corticomedullary type pattern with a hyperintense central area surrounded by a hypointense rim of tissue. The outline of the left adrenal gland was always very clear. The clarity of outline of the right adrenal gland was more variable, especially if it was in contact with the liver or the caudal vena cava. It was felt that the amount of retroperitoneal fat was not as important as stated in the human literature for visualization of the adrenal glands and that with an appropriate selection of scan planes and pulse sequences good assessment of the adrenal glands can be performed with MRI in canine patients.     

Ultrasonographic evaluation of the adrenal glands in six dogs with hypoadrenocorticism.

The purpose of this study was to determine the value of ultrasonographic characterization of the adrenal glands in dogs with hypoadrenocorticism. Measurements of adrenal glands were obtained in six dogs with hypoadrenocorticism. The adrenal glands on both sides were shorter (range: left adrenal gland length, 10.0 to 19.7 mm; right adrenal gland length, 9.5 to 18.8 mm) and thinner (range: left adrenal gland thickness, 2.2 to 3.0 mm; right adrenal gland thickness, 2.2 to 3.4 mm) than in normal dogs (range: left adrenal gland length, 13.2 to 26.3 mm; right adrenal gland length, 12.4 to 22.6 mm; left adrenal gland thickness, 3.0 to 5.2 mm; right adrenal gland thickness, 3.1 to 6.0 mm). Statistical analysis revealed a significant reduction in size of the left adrenal gland (p less than 0.05) in dogs with hypoadrenocorticism compared to the left adrenal gland in normal dogs. The results of this study show that atrophy of the adrenal glands in dogs with hypoadrenocorticism seems to lead to an ultrasonographic-measurable reduction in size of the adrenal glands.     

ADRENAL ULTRASONOGRAPHY CORRELATED WITH HISTOPATHOLOGY IN FERRETS

The adrenal glands of twenty-six, 12-to 53-month-old, ferrets without clinical signs of adrenal disease were examined and measured by ultrasonography and the findings compared with those from gross examination and histopathology. Of 51 adrenal glands examined, 27 were normal, 23 had either nodular or diffuse cortical hyperplasia and 1 had an adenocarcinoma. There was no statistically significant difference between the sonographic nor gross size of normal adrenal glands and those with hyperplasia. Moderate correlation was found between gross and sonographic measurements of length for both right (r=0.783; p<0.0001) and left (r=0.609; p<0.001) adrenal glands; however, the sonographic measurements were less than the gross measurements. Correlation was found between the sex and weight of the ferret and adrenal gland length (p<0.01) and width (p<0.02). In female ferrets, the length, width, and depth of the right adrenal gland sonographically measured (mean±sd) 7.5±1.2 mm, 3.7±0.6 mm, 2.8±0.4 mm, respectively, and the left measured 7.4±1.0 mm, 3.7±0.4 mm, 2.8±0.4 mm; in males, the right adrenal measured 8.9±1.6 mm, 3.8±0.6 mm, 3.0±0.8 mm and the left measured 8.6±1.2 mm, 4.2±0.6 mm, 3.0±0.6 mm. Accessory adrenal tissue was not identified during the sonographic examination but was grossly found in 10 of the ferrets. It was associated with either the right, left or both adrenal glands.     

Ultrasonographic measurement of the adrenal gland-to-abdominal aortic ratio as a valuable method of estimating normal adrenal size in rabbits

A wide range has been reported for the ultrasonographic measurements of the normal adrenal gland in rabbits. Therefore, having sufficient information about the normal measurements of the adrenal gland and their relationship with indicators such as weight, sex and the diameter of the internal abdominal aorta will be of great help in diagnosing diseases of the adrenal gland. In the present study, 21 healthy adult intact rabbits were selected. The abdominal cavity of the animals was examined using ultrasound; adrenal gland parameters such as length, width, height, circumference and area on the right and left sides were measured in both sagittal and transverse planes. Additionally, the diameter of the abdominal aorta in the sagittal plane was imaged. After statistical analysis, the parameters of the adrenal glands on the right and left showed a positive significant correlation with the weight and the diameter of the abdominal aorta, although no significant correlation was found between these parameters and sex. The ratio of adrenal gland parameters to abdominal aortic diameter was calculated and the statistical analysis of the values showed that, except for the ratio of left adrenal area to aortic diameter, the other ratio of adrenal gland parameters to abdominal aortic diameter was not significantly related to weight. Therefore, these ratios can be used as suitable indicators for assessing the change in size of the adrenal gland of rabbits of different sizes. Knowing the relationship between normal adrenal measurements and the indices such as weight, sex and diameter of the abdominal aorta can help clinicians and researchers evaluate the changes in the size of the adrenal gland.     

Ultrasonographic measurements of adrenal glands in cats with hyperthyroidism

Feline hyperthyroidism is potentially associated with exaggerated responsiveness of the adrenal gland cortex. The adrenal glands of 23 hyperthyroid cats were examined ultrasonographically and compared to the adrenal glands of 30 control cats. Ten hyperthyroid cats had received antithyroid drugs until 2 weeks before sonography, the other 13 were untreated. There was no difference in adrenal gland shape between healthy and hyperthyroid cats: bean-shaped, well-defined, hypoechoic structures surrounded by a hyperechoic halo in 43/60 (71.6%) healthy cats and 34/46 (73.9%) hyperthyroid cats; more ovoid in 13/60 (21.6%) healthy cats and 9/46 (19.6%) hyperthyroid cats while more elongated in 4/60 (6.7%) healthy cats, 3/46 (6.5%) hyperthyroid cats. Hyperechoic foci were present in 9/23 (39.1%) hyperthyroid cats and 2/30 (6.7%) healthy cats. The adrenal glands were significantly larger in hyperthyroid cats, although there was overlap in size range. The mean difference between hyperthyroid cats and healthy cats was 1.6 and 1.7 mm in left and right adrenal gland length, 0.8 and 0.9 mm in left and right cranial adrenal gland height, and 0.4 and 0.9 mm in left and right caudal adrenal gland height. There was no significant difference between the adrenal gland measurements in treated and untreated hyperthyroid cats. The adrenomegaly was most likely associated with the hypersecretion of the adrenal cortex documented in hyperthyroid cats. Hyperthyroidism should be an alternative to hyperadrenocorticism, hyperaldosteronism, and acromegaly in cats with bilateral moderate adrenomegaly.     

Luteinizing hormone-dependent Cushing's syndrome in a pet ferret (Mustela putorius furo)

Hyperadrenocorticism in ferrets is associated with increased circulating concentrations of adrenal androgens, whereas plasma concentrations of cortisol and ACTH are usually not affected. Here, we report on a 5-year-old castrated male pet ferret (Mustela putorius furo) in which the major presenting signs were polyuria and polyphagia. Routine biochemistry values were within their reference ranges. The urinary corticoid:creatinine ratio (UCCR) was increased and the plasma ACTH concentration was suppressed. Abdominal ultrasonography revealed an enlarged right adrenal gland and atrophy of the left adrenal gland. Administration of hCG resulted in an increase of plasma cortisol and androstenedione concentrations. Based on these findings LH/hCG-dependent hypercortisolism and hyperandrogenism were suspected and treatment was started with a depot GnRH-agonist implant containing 9.4mg deslorelin. Within 3 weeks after placement of the implant all clinical signs had disappeared. Three months later the endocrine parameters had normalized, while abdominal ultrasonography revealed that the right adrenal gland had diminished in size and the left adrenal gland was considered of normal size. No recurrences of clinical signs were seen within 2 years after placement of the deslorelin implant. At that time urinary corticoid and plasma hormone concentrations were within their reference ranges, and no further change in the size of the adrenal glands was seen. In conclusion, this is the first confirmed case of LH-dependent hypercortisolism in a ferret that was treated successfully with a depot GnRH-agonist.     

Effects of mitotane therapy in dogs with pituitary dependent Cushing syndrome on the adrenal gland size--an ultrasonographic study]

The effect of mitotane therapy on adrenal gland size was evaluated in 13 dogs with pituitary dependent hyperadrenocorticism. Ultrasonographic measurements were obtained before and during mitotane therapy. During therapy both adrenal glands were shorter and thinner (median during therapy: left adrenal gland 19.4 mm long, 5.4 mm thick, right adrenal gland 18.1 mm long, 6.1 mm thick) than before mitotane therapy (median before therapy: left adrenal gland 23.6 mm long, 8.3 mm thick, right adrenal gland 21.6 mm long, 8.1 mm thick). Statistical evaluation showed a significant reduction in size. But ultrasonographic measurement of adrenal gland size is not useful in the evaluation of adrenal reserve during mitotane therapy. Inadequate adrenal reserve was not identified and adrenal size measurement by ultrasonography was not helpful to differentiate adequate and inadequate control of adrenal cortisol secretion during mitotane therapy.     

Blood supply of the ovine adrenal gland and its relevance in adrenal autotransplantation

SUMMARY The arterial supply and venous drainage of 62 left and 5 right ovine adrenal glands is described, and the contribution of individual arteries to successful adrenal gland autotransplantation was evaluated. Arterial flow was measured by direct collection from the draining adrenal vein. Assessment of function of the transplanted adrenal gland was made from survival of the sheep and by the cortisol response to infusion of ACTH and the aldosterone secretory response to infusion of angiotensin II or potassium. For the left adrenal, the principal arterial supply was from the renal artery in 21 (34%), a lumbar artery in 32 (52%), and the anterior mesenteric artery in 3. The total blood flow was 5.0 ± SEM 0.4 mL/min, the flow from the renal branch 2.3 ± 0.3 mL/min, and the principal lumbar branch 2.6 ± 0.3 mL/min. Venous drainage from the left adrenal was via a major adrenal vein to the left renal vein, but additional tributaries to the renal vein were present in 26% . The arterial supply to the adrenal is regional and omission of a branch at transplantation could result in infarction of portion of the gland. By defining arterial supply and measuring blood flow, selection of the appropriate artery or multiple arteries can achieve an adrenal gland autotransplant survival of 90% .     

TRANSRECTAL ULTRASONOGRAPHY OF THE LEFT ADRENAL GLAND IN HEALTHY HORSES

Little information is available on medical imaging of the adrenal glands in horses. We investigated the feasibility of transrectal ultrasonography to characterize the normal equine adrenal gland. Transrectal ultrasonography was performed in 25 healthy horses using a 7.5 MHz linear array probe at a displayed depth of 8 cm. Transrectal ultrasonography of the right adrenal gland was not feasible. For the left adrenal gland, the left kidney, the abdominal aorta, the left renal artery, the left renal vein, and the cranial mesenteric artery were used as landmarks. The size of the left adrenal gland was variable, but it generally appeared as a long, flat structure with a hyperechoic medulla surrounded by a hypoechoic cortex. The most cranial part of the gland could not be delineated appropriately in 11 horses (44%). The mean (±SD) thickness of the gland and medulla was 0.66±0.15 cm (n=25) and 0.28±0.09 cm (n=25) near the caudal pole, 0.87±0.25 cm (n=14) and 0.40±0.18 cm (n=12) near the cranial pole, and 0.89±0.18 cm (n=25) and 0.36±0.13 cm (n=25) in the middle of the gland, respectively. The mean (±SD) length of the entire adrenal gland and of the medulla was 6.22±0.77 cm (n=14) and 5.45±0.71 cm (n=6), respectively. Transrectal ultrasonography allowed adequate visualization of the left adrenal gland in horses.     

IMAGING DIAGNOSIS—RADIOGRAPHY AND ULTRASONOGRAPHY OF BILATERAL CONGENITAL URETEROVESICAL JUNCTION STENOSIS CAUSING HYDRONEPHROSIS AND HYDROURETER IN A FERRET (MUSTELA PUTORIUS FURO)

An 8‐month‐old neutered male ferret was presented for vaccination and preventive treatment for adrenal gland disease. Abdominal ultrasound revealed severe bilateral hydronephrosis and hydroureter. Excretory urography and negative contrast cystography showed bilateral ureterovesical junction stenosis. Positive retrograde cystography demonstrated right ureteral reflux. A subcutaneous ureteral bypass was placed in the left kidney; however, it had to be removed 3 months later due to an obstruction and persistent urinary tract infection. Bilateral ureteroneocystotomy was performed. Although congenital strictures are uncommon in veterinary patients, they should be included in the differential diagnosis in ferrets presenting with hydronephrosis and hydroureter of undetermined cause.     

Use of x-ray-computed tomography as an aid in localization of adrenal masses in the dog

Four dogs with clinical evidence of hyperadrenocorticism were evaluated by use of x-ray-computed tomography (CT). Adrenal masses were identified accurately and localized. Unilateral adrenal masses were diagnosed accurately in dogs 1, 2, and 3 and were removed surgically via a paracostal retroperitoneal approach to the adrenal gland. Using CT and IV contrast medium, the adrenal mass in dog 3 also was accurately diagnosed as being highly vascular. The histopathologic diagnosis was adrenal adenoma in dogs 1, 2, and 3. In dog 4, the CT-roentgen diagnosis was asymmetric bilateral adrenal enlargement. Necropsy examination of dog 4 indicated moderate enlargement of the left adrenal gland and severe enlargement of the right adrenal gland. Results of microscopic examination indicated chronic inflammation of the left adrenal gland and adenocarcinoma of the right adrenal gland. Use of CT facilitated localization of adrenal masses and fulfilled the needs of a localizing technique. A unilateral mass can be removed surgically via a limited exposure, retroperitoneal incision on the affected side of the animal instead of removal via abdominal laparotomy, which is more invasive. Advantages of CT can reduce the needs of other imaging modalities for the localization of adrenal masses.     

COMPUTED TOMOGRAPHIC QUANTIFICATION OF CANINE ADRENAL GLAND VOLUME AND ATTENUATION

We conducted a retrospective study in presumed normal dogs to determine the adrenal gland attenuation and volume values. Multidetector computer tomography (MDCT 16) analysis of the gland was carried out in 48 adult dogs without evidence of adrenal gland disease that underwent CT examination for acute spinal injuries. The mean nonenhanced attenuation value +/- SD of the left adrenal gland was 36.0 +/- 5.3 HU (range: 22.0-42.0 HU). The mean nonenhanced attenuation value +/- SD of the right gland was 34.3 +/- 7.0 HU (range: 20.4-48.6HU). The mean enhanced attenuation value +/- SD were: left gland 101.5 +/- 10.6HU (range: 86.8-128.0 HU), and right gland 97.4 +/- 12.4 HU (range: 58.9-123.6 HU). The mean CT volume +/- SD were: left gland was 0.60 cm3 (range: 0.20-0.95; SD 0.17), and right gland (0.55cm3, range: 0.22-1.01; SD 0.19). Attenuation values and volume data were related to age, weight, and gender, using ANOVA. There was no statistically significant difference between the left and right side or in adrenal measurements, because of body weight class effects. The animal effect was the most important source of variation for all adrenal measurements. Based on our study, CT is an effective method for assessing adrenal characteristics in the dog. Normative CT data are provided to allow estimation of normal adrenal gland size and volume.     

Functioning unilateral adrenocortical carcinoma in a dog

An 11-year-old, 24-kg, intact female Siberian husky dog in anestrus had a 2-month history of polyuria and polydipsia. The dog had signs of mineralocorticoid excess such as hypertension and hypokalemia refractory to potassium supplementation. Abdominal ultrasound revealed an irregular mass in the left adrenal gland. The ACTH stimulation test for aldosterone concentration did not reveal hyperaldosteronism. Unilateral adrenalectomy was performed and histopathology identified adrenal cortical carcinoma. All clinical signs of mineralocorticoid excess ceased after surgery.     

Assessment of survey radiography and comparison with x-ray computed tomography for detection of hyperfunctioning adrenocortical tumors in dogs

Results of abdominal survey radiography and x-ray computed tomography (CT) were compared in 13 dogs with hyperadrenocorticism histologically attributed to adrenocortical tumors. X-ray computed tomography enabled accurate localization of the tumor in all 13 dogs. Apart from 2 poorly demarcated irregular-shaped and mineralized carcinomas, there were no differences between adenoma (n = 3) and carcinoma (n = 10) on CT images. In 1 dog, invasion of the caudal vena cava by the tumor was suggested on CT images and was confirmed during surgery. Suspicion of adhesions between tumors of the right adrenal gland and the caudal vena cava on the basis of CT images was confirmed during surgery in only 2 of 6 dogs. Survey radiography allowed accurate localization of the tumor in 7 dogs (4 on the right side and 3 on the left). In 6 of these dogs, the tumor was visible as a well-demarcated soft tissue mass and, in the other dog, as a poorly demarcated mineralized mass. The smallest tumor visualized on survey radiographs had a diameter of 20 mm on CT images. Six tumors with diameter less than or equal to 20 mm were not visualized on survey radiographs. In 1 of these dogs, a mineralized nodule was found in the left adrenal region, without evidence of a mass. In a considerable number of cases, survey radiography can provide presurgical localization of adrenocortical tumors in dogs with hyperadrenocorticism; CT is redundant in these instances. In the absence of positive radiographic findings, CT is valuable for localization of adrenocortical tumors.     

Budd-Chiari-like syndrome associated with an adrenal phaeochromocytoma in a dog

A nine-year-old dog was presented with sudden-onset ascites and a history of two previous syncopal episodes. Diagnostic tests pointed to a Budd-Chiari-like syndrome, with obstruction of the caudal vena cava between the liver and heart. The ascites was refractory to treatment and the dog was euthanased. On postmortem examination, a phaeochromocytoma of the left adrenal gland was present, with contiguous invasions into the caudal vena cava, extending cranially as far as the cavoatrial junction. To the authors' knowledge, this is the first reported case of a Budd-Chiari-like syndrome associated with a phaeochromocytoma in a dog.