Equine laryngeal dysplasia as a cause of acute respiratory distress in a neonatal foal

Equine laryngeal dysplasia (ELD) is a congenital disorder caused by hypoplasia or aplasia of the structures derived from the fourth and possibly sixth branchial arches. The severity of the clinical signs varies widely, and depends on which structures are involved and the extent of the defect. In most cases, affected horses present with abnormal respiratory noise during exercise and poor performance. Manifestation of the disease in foals is very rare. This case report describes an unusual presentation of ELD in a neonatal foal. The foal presented with severe respiratory distress and weakness. Equine laryngeal dysplasia was suspected on endoscopy and later confirmed on post mortem examination of the larynx. To the best of our knowledge, this is the first report describing ELD as a cause of respiratory distress in a neonatal foal.     

Cricopharyngeal-laryngeal dysplasia in a horse with sudden clinical onset idiopathic laryngeal hemiparesis

A 7-year-old Thoroughbred racehorse developed loud exercise-related respiratory noises and exercise intolerance over a short period. Examination showed congenital cricopharyngeal-laryngeal dysplasia (rostral displacement of the palatopharyngeal arch) and also left sided idiopathic laryngeal hemiparesis, the latter appearing to be of recent clinical onset. The animal developed colic some months after laryngeal surgery and a nephrosplenic entrapment was surgically corrected. Aerophagia and regurgitation worsened after surgery and, after developing inhalation pneumonia, the animal was destroyed. Post-mortem examination confirmed the presence of idiopathic laryngeal hemiparesis and of cricopharyngeal-laryngeal dysplasia which had some previously undescribed laryngeal muscle abnormalities.     

Cricopharyngeal-laryngeal dysplasia in a horse with sudden clinical onset idiopathic laryngeal hemiparesis

A 7-year-old Thoroughbred racehorse developed loud exercise-related respiratory noises and exercise intolerance over a short period. Examination showed congenital cricopharyngeal-laryngeal dysplasia (rostral displacement of the palatopharyngeal arch) and also left sided idiopathic laryngeal hemiparesis, the latter appearing to be of recent clinical onset. The animal developed colic some months after laryngeal surgery and a nephrosplenic entrapment was surgically corrected. Aerophagia and regurgitation worsened after surgery and, after developing inhalation pneumonia, the animal was destroyed. Post-mortem examination confirmed the presence of idiopathic laryngeal hemiparesis and of cricopharyngeal-laryngeal dysplasia which had some previously undescribed laryngeal muscle abnormalities.     

Radiographic features of two cases of feline proximal femoral dysplasia

Congenital or acquired feline femoral dysplasia have seldom been reported in the literature. This report describes two cases of femoral dysplasia involving the proximal epiphyses. Bilateral agenesis of the femoral head and neck (case 1) constituted an incidental finding during a post-traumatic radiographic examination, while right proximal femoral dysplasia (case 2) was observed during an orthopaedic examination for lameness. To the authors' knowledge, such imaging findings have not been reported before in cats.     

Computed tomography versus arthroscopy for detection of canine elbow dysplasia lesions

Objective— To describe associations between computed tomography (CT) and arthroscopy in dogs with elbow dysplasia lesions.
Study Design— Retrospective clinical study.
Sample Population— Canine elbows (n=101) investigated by CT and arthroscopy.
Methods— CT scans were reviewed for 10 predetermined CT signs and graded for osteophyte size. Surgical reports were reviewed for specific disease features and cartilage erosion grades. Associations between variables were investigated with multivariate logistic regression and correlation between osteophyte size and cartilage erosion with Spearman's rank order correlation.
Results— Medial coronoid process (MCP) fragment on CT was significantly associated with the arthroscopic identification of a displaced MCP fragment, cartilage erosion affecting the MCP, and cartilage erosion affecting the humeral condyle. Irregular radial incisure of the ulna on CT was significantly associated with the arthroscopic identification of cartilage erosion affecting the MCP. Osteophytes on CT were significantly associated with an abnormal arthroscopic examination. There was a moderately significant correlation between CT osteophyte grade and cartilage erosion grades for areas of the medial joint compartment (r_s=0.44–0.48).
Conclusion— Some CT signs are significantly associated with arthroscopic features of elbow dysplasia lesions in dogs; however, other CT signs were not associated with arthroscopic findings, and CT and arthroscopy can provide contradictory information. Osteophyte size is moderately correlated with cartilage erosion of the medial joint compartment.
Clinical Relevance— CT can provide valuable information for the investigation of dogs with elbow dysplasia, but the absence of CT signs (or the absence of arthroscopic abnormalities) does not rule out elbow lesions.     

Clinical and laryngoscopic findings in a Swiss Alpine goat with left grade 4 laryngeal hemiplegia

This case report describes the diagnostic trial of an inspiratory wheeze in a 1.5-year-old Swiss Alpine goat. Left grade 4 laryngeal hemiplegia was diagnosed via laryngoscopy, whereas the severity of the hemiplegia was assessed according to the grading system used in horses.The results of clinical, radiographic, sonographic and endoscopic examinations as well as haematological, biochemical and serological analyses did not reveal the cause of the hemiplegia. Treatment with an antibiotic and vitamin B complex resulted in only slight improvement. A postmortem examination four months later revealed no gross lesions in the left laryngeal nerve, larynx and intrinsic laryngeal musculature. Histological examination of the nerve, arytenoid cartilage and intrinsic laryngeal musculature also showed no lesions. Therefore, the cause of the disease in this goat is suspected to be on the cellular or molecular level of the intrinsic laryngeal musculature.     

COMPUTED TOMOGRAPHIC IMAGING OF DOGS WITH PRIMARY LARYNGEAL OR TRACHEAL AIRWAY OBSTRUCTION

Seventeen dogs with clinical signs attributable to nonneoplastic obstruction of the larynx, trachea, or large bronchi underwent computed tomography (CT) imaging. In 16 of the 17 dogs, CT was performed without general anesthesia using a positioning device. Fifteen of these 16 dogs were imaged without sedation or general anesthesia. Three‐dimensional (3D) internal rendering was performed on each image set based on lesion localization determined by routine image planes. Visual laryngeal examination, endoscopy, video fluoroscopy, and necropsy were used for achieving the cause of the upper airway obstruction. The CT and 3D internal rendering accurately indicated the presence and cause of upper airway obstruction in all dogs. CT findings indicative of laryngeal paralysis included failure to abduct the arytenoid cartilages, narrowed rima glottis, and air‐filled laryngeal ventricles. Laryngeal collapse findings depended on the grade of collapse and included everted laryngeal saccules, collapse of the cuneiform processes and corniculate processes, and narrowed rima glottis. Trachea abnormalities included hypoplasia, stenosis, or collapse syndrome. The CT findings in tracheal hypoplasia consisted of a severely narrowed lumen throughout the entire length. Tracheal stenosis was represented by a circumferential decrease in tracheal lumen size limited to one region. Tracheal collapse syndrome was diagnosed by severe asymmetric narrowing. Lobar bronchi collapse appeared in CT images as a narrowed asymmetric lumen diameter. CT imaging of unanesthetized dogs with upper airway obstruction compares favorably with traditional definitive diagnostic methods.     

Chronic upper airway obstruction caused by laryngeal adenocarcinoma in a cat

An eight-year-old spayed female cat developed upper respiratory obstruction, abnormal vocalisation and anorexia over a period of a few months. Examination under general anaesthesia revealed unilateral laryngeal distortion by a soft tissue mass; there was no radiographic evidence of metastatic disease at this time. Over the next four months the upper respiratory obstruction became more severe as a result of progressive laryngeal stenosis and metastatic lung masses were observed radiographically four months after initial examination. Necropsy revealed an infiltrating laryngeal adenocarcinoma with metastases in the upper cervical lymph node and lungs. This case illustrates the value of early biopsy diagnosis to spare the patient the distress of progressive upper respiratory obstruction.     

DYSPLASIA EPIPHYSEALIS HEMIMELICA IN A BOXER PUPPY

A Boxer puppy had an unusual dysplastic lesion of the distal epiphysis of the left femur. Biopsy and CT examination were performed. A diagnosis of dysplasia epiphysealis hemimelica (DEH) was made. To the investigators knowledge, this condition has not been described before in animals. DEH is a growth disorder involving preferentially the medial compartment of the lower limbs, and it is associated with epiphyseal hypertrophy and delayed mineralization.     

Diagnosis of laryngeal dysplasia in five horses using magnetic resonance imaging and ultrasonography

Reasons for performing study: Laryngeal dysplasia due to suspected maldevelopment of the fourth branchial arch has been reported previously in the horse and has been associated with rostral displacement of the palatopharyngeal arch and/or right laryngeal dysfunction. These studies all described the endoscopic and/or anatomical post mortem identification of the disease, but ultrasonography or magnetic resonance imaging (MRI) of this disease have not been described. Hypothesis: MRI and ultrasound findings accurately reflect the anatomical features of presumptive fourth branchial arch abnormality and allow accurate ante mortem diagnosis of this condition and, therefore, appropriate management. Methods: Between February 2008 and January 2009, all horses examined at Rood and Riddle Equine Hospital diagnosed with rostral displacement of the palatopharyngeal arch and/or right laryngeal dysfunction using upper airway endoscopy (n = 5) underwent ultrasonography and MRI of the laryngeal region. Results: All 5 horses that met the inclusion criteria were identified and all underwent laryngeal MRI and ultrasound examinations. Features consistent with laryngeal dysplasia, including lack of the cricothyroid articulation, dorsal extension of the thyroid cartilage lamina, and absence or hypoplasia of the cricopharyngeus muscle, were seen in all cases using both types of imaging. Conclusions and potential relevance: MRI and ultrasonography permit definitive premortem diagnosis of laryngeal dysplasia. Upper airway abnormalities identified using endoscopy can be more fully characterised using MRI and ultrasonography allowing more appropriate recommendations to be made. Preoperative imaging may also prevent inappropriate surgical intervention.     

COMPUTED TOMOGRAPHIC IDENTIFICATION OF DYSPLASIA AND PROGRESSION OF OSTEOARTHRITIS IN DOG ELBOWS PREVIOUSLY ASSIGNED OFA GRADES 0 AND 1

Elbow dysplasia is a heritable disease that is a common cause of lameness and progressive elbow osteoarthritis in young large breed dogs. The Orthopedic Foundation for Animals (OFA) screens elbow radiographs, and assigns grades 0–3 based on presence and severity of bony proliferation on the anconeal process. Grade 1 is assigned when less than 3 mm is present and considered positive for dysplasia. We investigated the incidence of elbow dysplasia and progression of osteoarthritis in elbows with grades 0 and 1 in 46 elbows screened at least 1 year previously, using CT as a gold standard and with the addition of CT absorptiometry. The incidence of dysplasia based on CT was 62% in grade 0, and 75% in grade 1 elbows, all of which had medial coronoid disease. Progressive osteoarthritis at recheck was consistent with elbow dysplasia. The sensitivity and specificity of the OFA grade for elbow dysplasia compared to CT findings was 75% and 38%, respectively. Increased bone mineral density of the medial coronoid process as characterized by osteoabsorptiometry warrants further investigation with respect to elbow dysplasia. Proliferation on the anconeal process without CT evidence of dysplasia or osteoarthritis was present in 20% of the elbows, and is theorized to be an anatomic variant or enthesopathy of the olecranon ligament/synovium. Results of our study suggest that the “anconeal bump” used for elbow screening by the OFA is a relatively insensitive characteristic, and support the use of CT for identifying additional characteristics of elbow dysplasia.     

Bilateral juvenile renal dysplasia in a Norwegian Forest Cat

Renal dysplasia is defined as a condition of disorganised development of renal parenchyma due to abnormal differentiation. The case of a 5-month-old intact male Norwegian Forest Cat with a history of polyuria and polydipsia is reported. Ultrasonographic examination showed a slight enlargement of kidneys. Biochemical parameters, haematological examinations and clinical signs were compatible with chronic renal failure (CRF). Histological examination was correlated with a primary tubular disorganisation and modification of glomerular compartment. The clinical history together with the histological lesions is consistent with bilateral juvenile renal dysplasia in this cat. To our knowledge, feline renal dysplasia has been reported in fetal infections with panleukopenia virus; no reports indicate the idiopathic origin in feline dysplastic lesions.     

Computed tomographic diagnosis of a fracture of the floor of the pelvis in a Thoroughbred foal

This case report describes the clinical and diagnostic imaging findings, treatment and outcomes of a 15-day-old Thoroughbred foal referred for the evaluation of severe left hindlimb lameness of 8 days' duration. Radiographic examination of the left hindlimb and transcutaneous ultrasonographic examination of the pelvis were unremarkable. A computed tomographic (CT) examination was performed to investigate the proximal aspect of the limb and the pelvis; CT scans of the thorax were also acquired. In this case, CT images allowed detection of a closed, slightly displaced, oblique wedge-like fracture of the left caudal ramus of the pubis and medial ramus of the ischium, allowing an accurate diagnosis to guide appropriate treatment and prognostication. The foal was treated with anti-inflammatory drugs and box-rest. A follow-up by telephone interview with the trainer 3 years later revealed that the horse is in full athletic activity without any residual gait alteration related to the pelvic fracture.     

RADIOGRAPHIC AND COMPUTED TOMOGRAPHY FINDINGS IN BELGIAN SHEPHERD DOGS WITH MILD ELBOW DYSPLASIA

We compared computed tomography (CT) and radiographic findings of Belgian shepherds with grade 1 or borderline elbow dysplasia to determine whether the radiopaque area dorsal to the anconeal process and seen in mediolateral 45° flexed radiographs is formed by osteophytes, or whether it is an anatomic variation. Eighteen dogs with screening results 0/1, 1/0, or one or both elbows graded as borderline were studied. The radiographs were evaluated according to International Elbow Working Group guidelines and compared with CT images. A fragmented medial coronoid process was seen in five joints, and remaining 31 joints were considered free of dysplasia based on CT images. In radiographs, height of the radiopaque area on the anconeal process was 0–2.7 mm in dysplastic and 0–3.0 mm in other joints. Sensitivity of this sign as dysplasia indicator was 40% and specificity 29%. All dysplastic joints and three of the other joints had blurring of the cranial edge of the medial coronoid process. Subtrochlear sclerosis was seen in four dysplastic joints and in three other joints. Both changes were significant indicators of dysplasia ( P <0.001). Sensitivity and specificity of these phenomena as dysplasia indicators were 80% and 90%, respectively. We conclude that the radiopaque area on the anconeal process might not always be osteophyte formation in Belgian shepherds and should not be used as the sole criterion for dysplasia. Blurring of the medial coronoid process cranial edge and ulnar trochlear notch sclerosis are reliable signs of elbow dysplasia and may be beneficial in screening protocols.     

A case of congenital unilateral hip dysplasia in a newborn calf

We describe the case of a Simmental calf with congenital unilateral hip dysplasia. In the initial physical exam, the calf was able to stand unsteady when helped and showed severe swinging lameness in the left hind limb. Unilateral hip laxity and a positive Ortolani sign indicated subluxation of the femur within the hip joint. This finding was further confirmed by radiographic examination which also showed malformation of the left femoral head and acetabulum. After a short period of clinical improvement the calf's health deteriorated and it was euthanized due to signs of severe coxarthrosis. Pathological examination of the affected hip joint revealed a severe acetabular and femoral dysplasia with an incomplete formation of the epiphysis of the femoral head and a chronic granulating coxarthritis without evidence of primary infectious events.     

Reoccurrence of a paranasal osteoma following surgical removal in a 6-month-old Warmblood filly

A 6-month-old Warmblood filly presented for evaluation of a left sided unilateral mucopurulent discharge of 5 weeks' duration. Upper airway endoscopy revealed a large, smooth mass in the region of the ethmoturbinates. Dorso-ventral and lateral radiographs of the head revealed a large osseous mass in the left paranasal area. A biopsy was performed under general anaesthesia and an osteoma was diagnosed. A computed tomography (CT) examination was performed to guide surgical removal. Surgery was performed under general anaesthesia and a large mass was removed ~15 × 9 cm. A CT examination 3 months following surgery revealed three small areas of mineralisation. It was difficult to differentiate if these were areas of regrowth or portions of the original mass that were not entirely removed. A CT examination 8 months later revealed one of the areas had increased moderately in size. A second surgery was performed standing to remove the growth. A final CT 8 months later revealed no further evidence of a bone growth. This report describes the successful removal of an osteoma regrowth following initial surgical removal and, to the best of the authors’ knowledge, is the first to describe the reoccurrence of an osteoma after surgical intervention. It also describes a successful rhinotomy in the standing equine patient. This case highlights the importance of serial follow-up imaging after surgical removal as osteoma regrowth occurred in this case.     

Renal dysplasia in a Rhodesian ridgeback dog

A six-month-old Rhodesian ridgeback dog was presented for evaluation of facial swelling. Chronic renal failure was clinically diagnosed based on urinalysis, biochemical changes and ultrasonography. The facial swelling was due to fibrous osteodystrophy, which was evident on survey radiographs of the skull. On post mortem examination, chronic renal failure as a result of renal dysplasia was confirmed. This is the first reported case of renal dysplasia in this breed of dog.     

Acquired bilateral laryngeal paralysis associated with systemic lupus erythematosus in a dog

A 4 yr old spayed female Labrador retriever was referred for acute respiratory distress and was found to have bilateral laryngeal paralysis. Physical examination and biochemical testing were consistent with systemic lupus erythematosus (SLE) and did not reveal a likely alternative cause for the laryngeal paralysis. Following immunosuppressive and supportive treatment, the dog regained normal laryngeal function. At a scheduled follow-up examination 6 wk later, normal laryngeal function was confirmed via sedated laryngeal examination. Laryngeal paralysis associated with SLE has been reported in humans, but this is the first known report of acquired laryngeal paralysis associated with SLE in the dog.     

COMPUTED TOMOGRAPHIC FEATURES OF BASIHYOID ECTOPIC THYROID CARCINOMA IN DOGS

Eight dogs with a firm, nonpainful swelling in the ventral laryngeal region and with a final diagnosis of ectopic thyroid carcinoma were investigated by Computed Tomography (CT) at six different institutions. Computed Tomography findings were reviewed, focusing on lesion volume, shape, margins, relationship with surrounding structures and adjacent vessels, attenuation characteristics, and presence of metastases. Ectopic thyroid carcinomas were seen as oval‐to‐bilobed masses centered on the basihyoid bone with associated bone lysis, highly vascularized capsules with central poorly contrast enhancing areas. In all cases there was laryngeal wall infiltration, in two dogs invasion of the laryngeal lumen and in one case invasion of the ventral muscular and subcutaneous plane. Metastases were found in retropharyngeal lymph nodes (three cases) and in the lung (two cases). Ectopic thyroid carcinoma should be considered in the differential diagnosis when a mass in the basihyoid region is present. Described CT features may be typical for ectopic thyroid neoplasia and could be used to help decide the therapeutic plan.