High-frequency ultrasound biomicroscopy findings of the skin of dogs with atopic dermatitis.

BACKGROUND: The high-frequency ultrasonographic appearance of skin of dogs with atopic dermatitis (cAD) has not been described. OBJECTIVES: To compare high-frequency ultrasonographic findings among lesional, macroscopically nonlesional skin of dogs with cAD, and the macroscopically nonlesional skin of healthy dogs. Additionally, to determine whether there is any correlation between the ultrasonographic findings in lesional skin and local Canine Atopic Dermatitis Extent and Severity Index, 4th iteration (CADESI-04) or its domains (erythema, lichenification, excoriations/alopecia). As a secondary aim, six cAD dogs were re-evaluated after management intervention. ANIMALS: Twenty dogs with cAD (six were re-examined after treatment) and six healthy dogs. MATERIALS AND METHODS: In all dogs, ultrasonographic examination was performed on the same 10 skin sites, using a 50 MHz transducer. Wrinkling of skin surface, presence/width of subepidermal low echogenic band, hypoechogenicity of dermis and thickness of the skin were evaluated and scored/measured blindly. RESULTS: Dermal hypoechogenicity was more common and severe in lesional compared to macroscopically nonlesional skin of dogs with cAD. In lesional skin, presence/severity of wrinkling of skin surface and of dermal hypoechogenicity were positively correlated with presence/severity of lichenification, while severity of dermal hypoechogenicity was positively correlated with local CADESI-04. A positive correlation between the change in skin thickness and the change in the severity of erythema during treatment was noted. CONCLUSIONS AND CLINICAL RELEVANCE: High-frequency ultrasound biomicroscopy may be useful for the evaluation of skin of dogs with cAD and for evaluating the progression of skin lesions during treatment.

Low-field magnetic resonance imaging characteristics of multifocal vertebral lesions in dogs.

BACKGROUND: There is a lack of information regarding magnetic resonance imaging (MRI) features of polyostotic vertebral lesions in dogs. The aim of this retrospective study was to identify and differenciate low-field MRI features of aggressive versus benign multifocal vertebral diseases in dogs. METHODS: MRI examinations from 49 dogs with polyostotic vertebral lesions were reviewed. Images were evaluated for vertebral intensity changes, expansile lesions, new bone formation, cortical bone interruption, paravertebral musculature changes, lymphadenomegaly, spinal cord compression and spinal cord signal changes. RESULTS: Twenty-nine dogs with non-aggressive bone lesions and 20 dogs with aggressive vertebral lesions were included. Non-aggressive lesions had variable T2-weighted fast spin-echo (T2W) signal intensity and the majority displayed low signal intensity on short tau inversion recovery (STIR). Aggressive lesions predominantly had high T2W and STIR signal intensity, with variable signal intensity on T1-weighted spin-echo and contrast enhancement. Aggressive lesions were associated with spinal pain (p < 0.01), new bone formation (p = 0.02), spinal cord compression (p < 0.01) and lymphadenomegaly (p < 0.01). Cortical interruption (p < 0.01) and paravertebral musculature changes (p < 0.01) were the strongest indicative imaging features for aggressive lesions. CONCLUSION: Spinal pain, spinal cord compression, new bone formation, lymphadenomegaly and especially cortical interruption and paravertebral musculature signal intensity changes were the best discriminators for differentiating malignant from benign vertebral lesions.

Low Field MRI Measurements of the Normal Canine Trigeminal Nerve.

There is no available measuring protocol and reference range for the normal canine trigeminal nerve. This can be problematic in cases of suspected bilateral trigeminal neuropathy since contralateral nerves cannot be a usefully compared. Trigeminal nerves and brain measurements were retrospectively assessed via multiplanar reconstruction (MPR) of 3DT1 post-contrast MR sequences from 137 dogs with no signs or diagnosis of trigeminal disease. Direct measurements of vertical brain height (BH), trigeminal nerves transverse height (TTH) and trigeminal nerves width in dorsal reconstruction (TDW) were made in a plane immediately caudal to the foramen ovale and used to derive trigeminal nerve-to-brain (NB) ratios, including height-to-brain ratio (HBR) and width-to-brain ratio (WBR). HBR (0.09, IQR = 0.08-0.09) and WBR (0.10, IQR = 0.09-0.11) maintained more consistent values across the study population compared to direct measurements of TTH (3.72, IQR = 3.42-4.07) and TDW (4.35 +/- 0.63). Calculated normal reference intervals for HBR and WBR were 0.07-0.11 and 0.08-0.13, respectively and the largest NB ratios recorded in normal dogs were 0.13 and 0.14 for HBR and WBR, respectively. All measurements varied proportionally with weight, including HBR (r = 0.41, p < 0.0001) and small dogs had a significantly smaller HBRs compared to medium (p = 0.0294), large (p < 0.0049) and giant dogs (p < 0.0044). Median HBR was the same across skull types (0.09), however post-hoc analysis detected significantly smaller HBRs in brachycephalic compared to mesaticephalic dogs (p = 0.0494). In conclusion, trigeminal NB ratios may allow for accurate, objective assessment of the canine trigeminal nerves on MRI but further quantification of the effects of weight and skull type on suggested reference intervals is needed.

Convergence-Retraction Nystagmus in a Dog With Presumptive Ischemic Encephalopathy Following Acute Cervicothoracic Myelopathy.

A 6.5-year-old male neutered Trailhound was admitted for hyperacute, nonprogressive, left-sided hemiparesis. Physical and neurologic examination revealed nonpainful, left-sided poorly ambulatory hemiparesis, decreased left-sided postural reactions and thoracic limbs hyporeflexia. Neuroanatomic localisation was consistent with a left-sided C6-T2 myelopathy. Haematology and biochemistry revealed nonspecific abnormalities. Magnetic resonance imaging of the neck revealed a focal intramedullary lesion at the level of C6-C7 vertebrae compatible with acute hydrated noncompressive nucleus pulposus extrusion or ischemic myelopathy. During the second day of hospitalization, the dog developed convergence-retraction nystagmus, up-gaze palsy and eyelid retraction (Collier's sign) compatible with dorsal midbrain syndrome. Magnetic resonance imaging of the brain revealed a focal lesion compatible with dorsal midbrain ischemic infarct. Further clinicopathologic testing, thoracic and abdominal imaging were unremarkable. Ischemic encephalopathy of unknown etiology was additionally diagnosed. Physiotherapy was performed therapeutically. At 1-year follow-up the dog was normal. This is an unusual report of a dog with myelopathy followed by ischemic encephalopathy with manifestation of convergence-retraction nystagmus in the absence of vestibular signs. This saccadic intrusion is a characteristic clinical manifestation of a dorsal midbrain syndrome localization. The importance of a complete differential diagnoses list formation in a dog with ischemic encephalopathy which leads to a thorough diagnostic investigation plan is highlighted. Moreover, this report contributes to the enrichment of the clinical reasoning veterinary literature on convergence-retraction nystagmus. To the authors' knowledge, this is the second case report (fourth dog) to describe convergence-retraction nystagmus in dogs as a manifestation of dorsal midbrain syndrome.

Ultrasonographic findings in cats with acute kidney injury: a retrospective study.

OBJECTIVES: The aims of the study were to identify the ultrasonographic findings in cats with acute kidney injury (AKI) and to assess whether they had prognostic value. METHODS: This was a descriptive case series. A search of the computerised records of the Queen Mother Hospital for Animals (Hatfield, UK) was performed for cats presenting with AKI between 2007 and 2016. Patients were excluded if they had historical data consistent with chronic kidney disease. Ultrasound images were reviewed for the presence of six renal ultrasonographic abnormalities: nephromegaly, cortical and medullary echogenicity, pyelectasia, and retroperitoneal and peritoneal fluid. Ultrasonographic findings were assessed individually and cumulatively to give an ultrasound score out of 6. Ultrasonographic findings were assessed for association with oligouria/anuria and survival. RESULTS: Forty-five cats with AKI fulfilled the inclusion criteria. In total, 6.7% (3/45) of cats had normal renal size and architecture. The most common renal ultrasonographic findings were nephromegaly, pyelectasia and increased renal echogenicity. The presence of retroperitoneal fluid was associated with oligouria/anuria. Total ultrasound score (out of 6) was significantly associated with oligouria/anuria and 6 month survival. CONCLUSIONS AND RELEVANCE: Ultrasonographic findings are common in cats presenting with AKI. The increasing number of renal ultrasonographic abnormalities and the presence of retroperitoneal fluid alone are associated with oligouria/anuria and a higher ultrasound score may suggest a poorer long-term prognosis.

ASSOCIATIONS BETWEEN DUAL-PHASE COMPUTED TOMOGRAPHY FEATURES AND HISTOPATHOLOGIC DIAGNOSES IN 52 DOGS WITH HEPATIC OR SPLENIC MASSES.

Ability to noninvasively differentiate malignant from nonmalignant abdominal masses would aid clinical decision making. The aim of this retrospective, cross-sectional study was to identify features in dual-phase computed tomographic (CT) studies that could be used to distinguish malignant from nonmalignant hepatic and splenic masses in dogs. Medical records were searched for dogs that had an abdominal dual-phase CT examination, a hepatic or splenic mass, and subsequent histopathologic diagnosis. Computed tomographic images for all included dogs were acquired prior to and <30 s (early phase) and >60 s (delayed phase) after intravenous contrast administration. Fifty-two dogs with 55 masses were studied: 24 hepatic, including 14 (58%) malignant and 10 (42%) non-malignant; 31 splenic, including 18 (58%) malignant and 13 (42%) nonmalignant. There was substantial overlap in the pre- and postcontrast CT features of malignant and nonmalignant hepatic and splenic masses. Regardless of histologic diagnosis, hepatic masses most frequently showed marked, generalized enhancement in early phase images that persisted in the delayed phase. Splenic hemangiosarcoma and nodular hyperplastic lesions most frequently showed marked, generalized enhancement in early phase images that persisted in delayed images whereas most splenic hematomas had slight enhancement in early phase images. All splenic hematomas and 77% of the hemangiosarcomas had contrast accumulation compatible with active hemorrhage. There were no other significant differences in quantitative or categorical CT data between malignant and nonmalignant hepatic or splenic masses. Dual-phase CT of dogs with hepatic or splenic masses provides limited specific diagnostic information.

Studying Cat (Felis catus) Diabetes: Beware of the Acromegalic Imposter.

Naturally occurring diabetes mellitus (DM) is common in domestic cats (Felis catus). It has been proposed as a model for human Type 2 DM given many shared features. Small case studies demonstrate feline DM also occurs as a result of insulin resistance due to a somatotrophinoma. The current study estimates the prevalence of hypersomatotropism or acromegaly in the largest cohort of diabetic cats to date, evaluates clinical presentation and ease of recognition. Diabetic cats were screened for hypersomatotropism using serum total insulin-like growth factor-1 (IGF-1; radioimmunoassay), followed by further evaluation of a subset of cases with suggestive IGF-1 (>1000 ng/ml) through pituitary imaging and/ or histopathology. Clinicians indicated pre-test suspicion for hypersomatotropism. In total 1221 diabetic cats were screened; 319 (26.1%) demonstrated a serum IGF-1>1000 ng/ml (95% confidence interval: 23.6-28.6%). Of these cats a subset of 63 (20%) underwent pituitary imaging and 56/63 (89%) had a pituitary tumour on computed tomography; an additional three on magnetic resonance imaging and one on necropsy. These data suggest a positive predictive value of serum IGF-1 for hypersomatotropism of 95% (95% confidence interval: 90-100%), thus suggesting the overall hypersomatotropism prevalence among UK diabetic cats to be 24.8% (95% confidence interval: 21.2-28.6%). Only 24% of clinicians indicated a strong pre-test suspicion; most hypersomatotropism cats did not display typical phenotypical acromegaly signs. The current data suggest hypersomatotropism screening should be considered when studying diabetic cats and opportunities exist for comparative acromegaly research, especially in light of the many detected communalities with the human disease.

Comparison of computed tomographic and pathologic findings in 17 dogs with primary adrenal neoplasia.

The CT appearance of canine adrenal masses has been reported, but associations between imaging features and pathologic features of these lesions have not been investigated in detail. The purpose of this study was to test associations between different types of adrenal neoplasia and their CT and pathologic features. A retrospective cross-sectional study was performed and inclusion criteria were histologic diagnosis of primary adrenal neoplasia, contrast-enhanced CT examination of the abdomen and surgical resection of the mass or necropsy examination. For all included dogs, CT images and histopathologic specimens were reviewed independently by two veterinary radiologists and a veterinary pathologist, respectively. Seventeen dogs met inclusion criteria. Diagnoses were adenocarcinoma in nine (53%) dogs, pheochromocytoma in five (29%) dogs, and adenoma in three (18%) dogs. Pheochromocytoma was associated with CT signs of vascular invasion (likelihood ratio = 4.8, 95% CI = 1.3-18.3, P = 0.03) and macroscopic vascular invasion (likelihood ratio = 9.6, 95% CI = 1.4-65.9, P = 0.02). There was excellent agreement between signs of vascular invasion in CT images and vascular invasion at surgery or necropsy (kappa = 0.86, P = 0.001). A peripheral contrast-enhancing rim in delayed postcontrast CT images was associated with fibrous encapsulation of the tumor (kappa = 0.53, P = 0.05), and a heterogeneous pattern of contrast distribution in delayed postcontrast CT images was associated with adrenal hemorrhage or infarction on histological examination (kappa = 0.45, P = 0.05). Findings indicated that CT enabled assessment of adrenal neoplasia features that reflected their biological behavior and pathological findings, however overlapping characteristics between tumor types limited the potential for reliably distinguishing them based on CT alone.

High-frequency ultrasound biomicroscopy of the normal canine haired skin.

BACKGROUND: The ultrasonographic appearance of the normal canine haired skin examined using high-frequency ultrasonography has not been described. HYPOSTHESIS/OBJECTIVES: To describe the echogenicity of normal canine haired skin using high-frequency (50 MHz) ultrasonography and to compare ultrasonographic with histological measurements of skin thickness using snap-frozen tissue biopsy samples. ANIMALS: Ten normal healthy beagle dogs. METHODS: Ultrasonographic examination was performed on eight cutaneous sites by use of a 50 MHz polyvinylidene difluoride transducer. The skin echogenicity was evaluated, and the mean of 10 skin thickness measurements was calculated. Ultrasonography results were compared with histological findings of skin cryosections stained with haematoxylin and eosin, as well as with histometric measurements of skin thickness. Differences in the ultrasonographic and histological measurements among biopsy sites, age and sex of the animals were also examined. RESULTS: The skin layers and hair follicles could be identified with high-frequency ultrasound biomicroscopy in all eight examination sites of all 10 dogs. There was a highly significant, positive association between the ultrasonographic and histological measurements (P < 0.001) of skin thickness. For both ultrasonographic and histological skin thickness measurements, there were no statistically significant differences between sex, age or among the different examination sites. CONCLUSIONS AND CLINICAL IMPORTANCE: Cutaneous ultrasound biomicroscopy using a 50 MHz transducer is a useful tool for the following applications: (i) to identify the skin layers (including the epidermis, dermis and subcutaneous fat); (ii) to demonstrate the hair follicles in various areas of the haired skin; and (iii) to measure the thickness of normal canine skin accurately.

Computed tomographic signs of acromegaly in 68 diabetic cats with hypersomatotropism.

In order to describe the signs of acromegaly in cats, a case-control study was done based on computed tomography (CT) scans of the heads of 68 cats with hypersomatotropism and 36 control cats. All cats with a diagnosis of hypersomatotropism had diabetes mellitus, serum insulin-like growth factor-1 >1000 ng/ml and a pituitary mass. Measurements of bones and soft tissues were done by two independent observers without knowledge of the diagnosis. Pituitary masses were identified in CT images of 64 (94%) cats with hypersomatotropism. Analysis of variance found a moderate effect of gender on the size of bones and a large effect of hypersomatotropism on the size of bones and thickness of soft tissues. In cats with hypersomatotropism the frontal and parietal bones were, on average, 0.8 mm thicker (P <0.001); the distance between the zygomatic arches was, on average, 5.4 mm greater (P <0.001); and the mandibular rami were, on average, 1.1 mm thicker (P <0.001) than in control cats. The skin and subcutis dorsal to the frontal bone were, on average, 0.4 mm thicker (P = 0.001); lateral to the zygomatic arch were, on average, 0.7 mm thicker (P <0.001); and ventral to the mandibular rami were, on average, 1.1 mm thicker (P = 0.002) in cats with hypersomatotropism than in control cats. The cross-sectional area of the nasopharynx was, on average, 11.1 mm(2) smaller in cats with hypersomatotropism than in control cats (P = 0.02). Prognathia inferior and signs of temporomandibular joint malformation were both observed more frequently in cats with hypersomatotropism than in control cats (P = 0.03). Overall, differences between affected and unaffected cats were small. Recognising feline acromegaly on the basis of facial features is difficult.

Mast cell morphometry and densitometry in experimental skin wounds treated with a gel containing adelmidrol: a placebo controlled study.

The role of skin mast cells (MCs) in wound healing has been extensively investigated. The present study was designed to examine the effect of the aliamide adelmidrol on MCs during healing of experimental cutaneous wounds. Adelmidrol gel or the vehicle alone was applied 3 times daily on 5-mm punch biopsy wounds created on the thoracolumbar skin of 10 dogs. Wounds were allowed to heal by secondary intention. Eight-mm punch samples of the healing wounds were taken on days 1, 2, 4, 8, and 14, for histology. Mast cell numbers were counted and granular content assessed by densitometric analysis on toluidine blue-stained sections. The overall mean granule content was significantly greater in the treated wounds compared to control wounds, whereas no statistically significant differences in MC counts were observed. These data indicate a reduction in MC degranulation in wounds topically treated with adelmidrol suggesting that the compound is able to down-modulate skin MC releasability without affecting their number.

Sinonasal plasmacytoma in a cat.

A 13-year-old female spayed Domestic Shorthair cat presented with a history of right-sided mucopurulent nasal discharge for 18 months. Computed tomography revealed a mass within the right nasal cavity and the right frontal sinus. The animal was euthanized, and a postmortem examination was performed. On macroscopic examination, the right nasal cavity and the right frontal sinus were partially occluded by a soft whitish mass. Microscopically, the mass was composed of well-differentiated plasma cells that were immunopositive for immunoglobulin G and lambda light chains. These findings were consistent with a mature-type sinonasal plasmacytoma. In addition, there was right-sided mucopurulent rhinitis and sinusitis caused by a Pasteurella infection, which probably developed secondary to the sinonasal plasmacytoma. To the authors' knowledge, this is the first report of a sinonasal plasmacytoma in a cat. The present communication shows that feline sinonasal plasmacytomas should be included in the differential diagnosis for tumors located in the upper respiratory tract of cats.

Veterinary e-CPD: a new model for providing online continuing professional development for the veterinary profession.

Continuing professional development (CPD) is widely recognized as an important element in effective lifelong learning for veterinary surgeons. Traditional methods of CPD do not suit all learners, as issues such as location, time, cost, and structure sometimes prevent individuals from completing the required number of CPD study hours per year. The rapid development of the Internet, and with it the increasing scope and sophistication of e-learning, provides new opportunities to address some of these constraints on the provision of CPD. This article describes one way in which e-learning has been deployed effectively to support veterinary surgeons in practice. Since 2003, a series of six-week e-CPD courses has been offered by the Royal Veterinary College (RVC) in an online format, with no face-to-face teaching component. Participants enrolled in courses from May 2006 to January 2007 were found to come from 23 different countries. Analysis of feedback forms indicates a general satisfaction with this new way of studying, with a significant majority of participants stating that they would wish to use this approach again in future. The feedback indicates that e-learning can offer an effective alternative to traditional face-to-face courses and that its popularity is likely to grow in future as veterinarians become increasing familiar with and confident about working online.

Assessment of the Effect of an Aliamide-containing Topical Gel by Evaluation of the Reduction of Wound Volume Measured by High R.

This study evaluated the use of an aliamide-containing gel in the treatment of skin wounds by employing noninvasive wound volume measurements acquired from wound images of high resolution ultrasonography (HRU). The dorsal thoracolumbar areas of 10 Beagle dogs were clipped and 2 rows of 6 full-thickness 5-mm punch biopsy samples were taken from either side of the midline under general anaesthesia. Wounds were allowed to heal by secondary intention, while treatment gel or base was applied 3 times daily to randomly selected treatment and control groups. Concentric 8-mm punch biopsy samples of the healing wounds were taken on Days 1, 2, 4, 8, and 14 for histopathological assessment. Wounds were imaged with 20 MHz HRU daily over a period of 28 days. Wound volume was calculated using scanner software based on the disk summation method. The wound volume was calculated in longitudinal and transverse ultrasound images and the average of the 2 values was used as the final wound volume. Repeated measures analysis of variance (ANOVA) was used to assess whether wound volume differed significantly over time, and between control and treated animals. Mean wound volume decreased significantly during the 28-day experimental period, and there was a significant time-treatment interaction indicating that the treatment effect varied at different stages during the healing process. Overall, application of the aliamide-containing gel appears to improve wound healing over time.

Utility of magnetic resonance imaging for distinguishing neoplastic from non-neoplastic brain lesions in dogs and cats.

The aim of this study was to identify magnetic resonance (MR) signs that aid differentiation of neoplastic vs. non-neoplastic brain diseases in dogs and cats. MR images of 36 dogs and 13 cats with histologic diagnosis of intracranial disease were reviewed retrospectively. Diagnoses included 30 primary and three metastatic brain tumors, 11 infectious/inflammatory lesions, three vascular, one degenerative disease, and one developmental malformation. Upon univariate analysis of 21 MR signs, there were seven that had a significant association with neoplasia: single lesion (P = 0.004), shape (P = 0.015), mass effect (P = 0.002), dural contact (P = 0.04), dural tail (P = 0.005), lesions affecting adjacent bone (P = 0.008), and contrast enhancement (P = 0.025). Increasing age was also found to be associated with neoplasia (P = 0.0001). MR signs of non-neoplastic brain diseases in dogs and cats were more variable than those of brain neoplasia.

Balloon dilatation of nasopharyngeal stenosis in a cat.

A cat was diagnosed with nasopharyngeal stenosis on the basis of clinical signs, survey and contrast radiography, endoscopy and magnetic resonance imaging. The condition was successfully managed with repeated balloon dilatation.

Changes in ultrasonographic appearance of adrenal glands in dogs with pituitary-dependent hyperadrenocorticism treated with trilostane.

Trilostane, a 3beta-hydroxysteroid dehydrogenase inhibitor, has been used successfully over the last few years for the treatment of canine pituitary-dependent hyperadrenocorticism. In a prospective study of 19 dogs with pituitary-dependent hyperadrenocorticism, the adrenal glands were measured before and at least 6 months after initiation of trilostane therapy. Right adrenal gland length and caudal pole thickness and left adrenal gland caudal pole thickness increased significantly (p < or = 0.05); there was no significant change in left adrenal gland length. Enlargement of adrenal glands during trilostane therapy may occur as a result of suppression of the negative feedback mechanism affecting cortisol production.