Weishaar's classification system for nodal metastasis in sentinel lymph nodes: Clinical outcome in 94 dogs with mast cell tumor.

BACKGROUND: The therapeutic role and prognostic relevance of lymphadenectomy in mast cell tumor (MCT) has historically been evaluated on regional rather than sentinel lymph nodes. HYPOTHESIS/OBJECTIVES: To update information about the association of histological nodal (HN) classes with clinical outcome in dogs with MCT after tumor excision and extirpation of normal-sized sentinel nodes (SLN) guided by radiopharmaceutical. ANIMALS: Ninety-four dogs with histologically-confirmed treatment-naïve MCT (71 cutaneous, 22 subcutaneous and 1 conjunctival MCT) were included if without: distant metastases, lymphadenomegaly, concurrent mixed cutaneous, and subcutaneous MCT. METHODS: This was a monoistitutional cohort study. Tumors characteristics were retrieved and SLNs were classified according to Weishaar's system. Incidence of MCT-related events (local, nodal, distant relapse), de novo MCT or other tumors and death (MCT-related and non-MCT-related), were recorded. Incidence curves were compared among the HN classes. RESULTS: Twenty-seven dogs had HN0, 19 HN1, 37 HN2, and 11 HN3 SLN. Thirteen (2 HN0, 4 HN2, and 7 HN3) received adjuvant chemotherapies. Kiupel high grade, increasing number of SLN and lymphocentrums were associated with higher HN classes. Five dogs died for MCT-related causes: 1 low-grade (HN0) and 1 subcutaneous (HN3) had a local relapse, 2 high-grade had distant relapse (HN3-HN0) and 1 dog developed disease progression from a de novo subcutaneous MCT. No nodal relapse was registered. Fourteen dogs developed de novo MCTs. CONCLUSION/DISCUSSION: Low grade/low-risk MCT with nonpalpable and normal sized SLN have a favorable outcome independently from the HN. Result should be considered strictly related to the successful SLN detection guided pre- and intraoperative by radiopharmaceutical markers.

Radiographic and CT features of metallosis in a lame dog after total hip replacement: the cloud sign.

A 2-year-old female American Akita was referred for CT of the pelvis and hindlimbs due to a left hindlimb lameness after a left total hip replacement. Referral radiographs and CT images demonstrated amorphous soft-tissue and mineral opacities surrounding the proximal femur and the prosthetic stem, consistent with the "cloud sign" reported as a characteristic of metallosis in humans. Dorsomedial displacement of the prosthetic head, multiple foci of geographic osteolysis alongside the "cloud sign", presumed pseudotumor lesions, and medial iliac lymphadenopathy were also identified with CT. Metallosis was confirmed based on ultrasound-guided cytology, revision surgery, and histopathology.

Evaluation of Surgical Aid of Methylene Blue in Addition to Intraoperative Gamma Probe for Sentinel Lymph Node Extirpation in 116 Canine Mast Cell Tumors (2017-2022).

Methylene Blue (MB) is combined with radiopharmaceutical for intraoperative sentinel lymph node (SLN) mapping, but its role during SLN extirpation has not been investigated yet in veterinary medicine. The aim of this study was to assess whether MB increased surgical detection of SLN beyond the use of intraoperative gamma-probe (IGP) alone in clinically node-negative dogs with mast cell tumors (MCTs) following the detection of sentinel lymphocentrums (SLCs) via preoperative planar lymphoscintigraphy. Dogs enrolled underwent MCT excision and SLC exploration guided by both MB and IGP. Data recorded for each SLN were staining (blue/non-blue), radioactivity (hot/non-hot), and histopathological status (HN0-1 vs. HN2-3). A total of 103 dogs bearing 80 cutaneous, 35 subcutaneous, and 1 mucocutaneous MCTs were included; 140 SLCs were explored, for a total of 196 SLNs removed. Associating MB with IGP raised the SLNs detection rate from 90% to 95%. A total of 44% of SLNs were metastatic: 86% were blue/hot, 7% were only blue, 5% were only hot, and 2% were non-blue/non-hot. All HN3 SLNs were hot. Combining MB with IGP can increase the rate of SLN detection in dogs with MCTs; nonetheless, all lymph nodes identified during dissection should be removed, as they might be unstained but metastatic.

Surgical complications following sentinel lymph node biopsy guided by γ-probe and methylene blue in 113 tumour-bearing dogs.

Sentinel lymph node biopsy (SLNB) is an accepted veterinary surgical procedure given the impact of early detection of nodal metastases on staging of several canine malignancies. This study aims at reporting the incidence and risk factors for surgical complications of SLNB in tumour-bearing dogs. A total of 113 client-owned dogs that underwent tumour excision and SLNB guided by γ-probing and blue dye were retrospectively enrolled. Recorded variables included: signalment, location and number of extirpated lymphocenters and nodes, time for SLNB, histopathological status of excised nodes. Incidence of SLNB complications was calculated. They were classified as minor and major based on severity and required treatment, and as short-term (0-30 days) and long-term (31-90 days). Univariate analysis with generalized linear model with binomial error estimated the association between variables and incidence of SLNB complications. Significance was set at 5%. Median overall time for SLNB was 25 min. Surgeons excised one node in 38% of dogs and multiple nodes in 62% of cases, belonging to one (62%) or multiple (38%) lymphocenters. Metastases were detected in 45% of nodes. No intraoperative complications occurred. The overall incidence of postoperative complications of SLNB was 21,24%, the majority of which (91.67%) were minor. Only increasing dogs' weight was associated with an increased incidence of SLNB complications (p = .00976). Sentinel lymphadenectomy was associated with a relatively low incidence of complications, most of which were self-limiting. The low morbidity and previously reported impact on staging of SLNB justify its implementation to collect data for prognostic studies.

Modular robotic platform for precision neurosurgery with a bio-inspired needle: System overview and first in-vivo deployment.

Over the past 10 years, minimally invasive surgery (MIS) has shown significant benefits compared to conventional surgical techniques, with reduced trauma, shorter hospital stays, and shorter patient recovery times. In neurosurgical MIS procedures, inserting a straight tool (e.g. catheter) is common practice in applications ranging from biopsy and laser ablation, to drug delivery and fluid evacuation. How to handle tissue deformation, target migration and access to deep-seated anatomical structures remain an open challenge, affecting both the preoperative planning phase and eventual surgical intervention. Here, we present the first neurosurgical platform in the literature, able to deliver an implantable steerable needle for a range of diagnostic and therapeutic applications, with a short-term focus on localised drug delivery. This work presents the system's architecture and first in vivo deployment with an optimised surgical workflow designed for pre-clinical trials with the ovine model, which demonstrate appropriate function and safe implantation.

Sentinel Lymph Node Biopsy Is Feasible in Dogs with Scars from Prior Local Excision of Solid Malignancies.

Sentinel lymph node (SLN) biopsy is a well-established staging tool in canine oncology. This study aims to explore the feasibility of SLN biopsy in dogs with scars from prior excised solid malignancies that were referred for further tumor staging and/or adjuvant treatment options. Mapping was either performed using radiopharmaceutical, methylene blue, and/or near-infrared fluorescent (NIRF) imaging. Thirty-three dogs with 34 scars from prior excision of the mast cell tumor (MCT) (n = 29), soft tissue sarcoma (n = 2), oral melanoma (n = 1), subungual melanoma (n = 1), and mammary adenocarcinoma (n = 1) were retrospectively enrolled. Primary treatment consisted of curative intent/wide tumor excisions in 50.0% of dogs and marginal excision in the remaining 50.0%. The median time between tumor excision and SLN biopsy was 50 days (range 17-110 days). The procedure was successful in 31/34 scars, translating to a detection rate of 91.2%. The SLN did not correspond to the regional lymph node in 19/31 scars (61.3%). SLN metastases were histologically identified in 13/31 (41.9%) dogs, all of them affected by MCT. Based on our results, SLN biopsy using lymphoscintigraphy/methylene blue and/or NIRF is feasible in dogs presenting with scars from the prior surgical excision of solid tumors, and should be suggested for accurate nodal staging.

Equine Suture Exostosis: A Review of Cases from a Multicenter Retrospective Study.

Suture exostosis is an intriguing and not uncommon pathology that has to be included in the differential diagnosis for horses with swelling of the head. Although several singular case reports have been published, no large case series is available. The aim of this study is to report a multicentric retrospective collection of suture exostosis cases. Data concerning horses with suture exostosis in the facial region were collected retrospectively. Information regarding breed, age, gender, history, imaging findings, initiated treatment, response to treatment and follow up was recorded. One hundred and five cases of various breeds were reported. Analysis revealed the cases could be grouped into four entities: 45 developed following sino-nasal surgery, 23 following trauma, seven with underlying sinus pathology and 25 idiopathic. Treatment consisted of sequestra removal, plate fixation, antimicrobial and anti-inflammatory drugs or no treatment. Whereas initial localized pain fades within few days or weeks, resolution or reduction of the swelling was obtained in most cases after 3 months to 1.5 years. The etiopathogenesis of suture exostosis seems to consist of different entities. Identification of an underlying cause, particularly the presence of a bone sequester and infection is important to speed up resolution and before concluding an idiopathic case. When performing sinusotomies, it is important to provide as little trauma as possible to the surgical site in order to prevent suture exostosis as a complication.

Fall time may be a reliable discriminator between neoplastic and non-neoplastic urinary bladder lesions in dogs undergoing contrast-enhanced ultrasound: a pilot study.

Contrast-enhanced ultrasound (CEUS) can provide quantitative information on enhancement patterns and perfusion of lesions, based on time-intensity curves (TICs). No published studies have compared CEUS parameters in neoplastic and non-neoplastic urinary bladder lesions in dogs. The aim of the current prospective, pilot study was to quantitatively characterize the CEUS pattern of neoplastic and non-neoplastic urinary bladder lesions in dogs, assessing the influence of contrast arrival time (CAT) on the final appearance of the curves. Fourteen dogs with cyto-histopathological diagnoses were included (seven malignant and seven inflammatory lesions). B-mode ultrasound was performed followed by CEUS examination after an intravenous bolus injection of 0.04 mL/kg of contrast medium, and TICs were elaborated by dedicated software. Receiver operating characteristic curves (ROC) for each TIC parameter were obtained. Neoplastic lesions had subjectively shorter rise time (RT), time to peak (TTP) and fall time (FT) than inflammatory lesions. Based on ROC curve analyses, fall time ≥ 10.49 s was the most reliable parameter for diagnosing non-neoplastic disease in this small sample of dogs (area under the curve [AUC] 0.75, sensitivity 83.33%, specificity 66.67%). No difference was found between ROCs calculated for each parameter of TICs by adding or removing CAT. Results of the current study provide background for future, larger scale studies evaluating use of a CEUS FT threshold of 10.49 s as a possible discriminator for urinary bladder neoplastic lesions in dogs.

Breed-specific vertebral heart score, vertebral left atrial size, and radiographic left atrial dimension in Cavalier King Charles Spaniels: Reference interval study.

Cavalier King Charles Spaniels (CKCS) are predisposed to developing myxomatous mitral valve disease (MMVD), with radiographs frequently used to screen for evidence of left-sided cardiomegaly secondary to MMVD. Vertebral heart size (VHS), vertebral left atrial size (VLAS), modified VLAS (M-VLAS), and radiographic left atrial dimension (RLAD) are reported as objective measurements of global heart size and left atrial size. Normal VHS in CKCS (10.6 ± 0.5) is reportedly higher than the non-breed-specific value (9.7±0.5). Breed-specific VLAS, M-VLAS, and RLAD cut-offs have not been reported in CKCS. The aim of this prospective reference interval study was to describe the VHS, VLAS, M-VLAS, and RLAD values for 30 clinically healthy adult CKCS. Inclusion criteria were unremarkable physical examination, normal echocardiography, and thoracic radiographs without malposition/abnormalities. There were 22 female and eight male dogs. Ages ranged from 1 to 6 years. The VHS mean value in our sample was 10.08 ± 0.56 (95% range, 9.87-10.29). This was significantly greater than a previously published general canine reference value of 9.7 ± 0.5 and significantly less than a previously published CKCS breed-specific value of 10.6 ± 0.5 (P < 0.01). Mean VLAS, M-VLAS, and the RLAD values in our study were 1.79 ± 0.3 (95% range, 1.68-1.9), 2.23 ± 0.44 (95% range, 2.06-2.39), and 1.2 ± 0.34 (95% range, 1.07-1.33), respectively. These were significantly less than previously published reference interval values (P < 0.001). The VHS, M-VLAS, and the RLAD were not affected by sex, body weight, or BCS; whereas the VLAS was moderately affected by body weight. Findings from this study can be used as background for future thoracic radiographic assessments in CKCS.

Preoperative planar lymphoscintigraphy allows for sentinel lymph node detection in 51 dogs improving staging accuracy: Feasibility and pitfalls.

Sentinel lymph node (SLN) mapping is the current gold standard for the oncological staging of solid malignancies in humans. This prospective observational study describes the feasibility and the limits of preoperative lymphoscintigraphy for SLN detection in dogs with spontaneous malignancies and the improvements in staging accuracy. Client-owned dogs with confirmed malignant neoplasia and absence of distant metastasis were prospectively enrolled. Lymphoscintigraphy was performed after the peritumoral injection of Technetium-99m labeled nanocolloids. Regional dynamic and static images were acquired, with and without masking of the injection site with a lead shield. The dogs were then subjected to surgery for tumor excision and SLN extirpation. Intraoperative SLN detection was performed by combining methylene blue dye and a dedicated gamma probe. Overall, 51 dogs with a total of 60 solid malignant tumors were enrolled. Lymphoscintigraphy identified at least one SLN in 57 of 60 cases (95%). The SLN did not always correspond to the regional lymph node (35/57, 61.4%). The use of a lead shield, masking the injection site, markedly improved the SLN visibility. The median time of SLN appearance was 11.4 ± 9.3 min. No side effects were observed. Preoperative lymphoscintigraphy allows for SLN detection in dogs and can improve staging accuracy by either identifying the SLN in a different lymphosome than clinically expected or discriminating the draining node in uncertain cases. The combined use of preoperative and intraoperative techniques is recommended to increase the SLN detection rate.

Development and in vivo assessment of a novel MRI-compatible headframe system for the ovine animal model.

BACKGROUND: The brain of sheep has primarily been used in neuroscience as an animal model because of its similarity to the human brain, in particular if compared to other models such as the lissencephalic rodent brain. Their brain size also makes sheep an ideal model for the development of neurosurgical techniques using conventional clinical CT/MRI scanners and stereotactic systems for neurosurgery. METHODS: In this study, we present the design and validation of a new CT/MRI compatible head frame for the ovine model and software, with its assessment under two real clinical scenarios. RESULTS: Ex-vivo and in vivo trial results report an average linear displacement of the ovine head frame during conventional surgical procedures of 0.81 mm for ex-vivo trials and 0.68 mm for in vivo tests, respectively. CONCLUSIONS: These trial results demonstrate the robustness of the head frame system and its suitability to be employed within a real clinical setting.

To map or not to map the cN0 neck: Impact of sentinel lymph node biopsy in canine head and neck tumours.

Tumour stage is a prognostic indicator for canine malignant head and neck tumours (MHNT). However, consensus is lacking on nodal staging in the absence of clinically apparent nodal disease (cN0 neck). This prospective observational study aims to determine the diagnostic accuracy of radiopharmaceutical and blue dye for sentinel lymph node biopsy (SLNB), to assess the correspondence between sentinel lymph node (SLN) and clinically expected regional lymph node (RLN) and the impact on staging of the procedure in dogs with MHNT and cN0 neck. Twenty-three dogs with MHNT and cN0 neck underwent tumour excision and SLNB guided by preoperative lymphoscintigraphy and intraoperative gamma-probe and blue dye. Diagnostic performances and detection rate were calculated. Correspondence between SLN and RLN, number of nodes excised, histopathological status of the SLN and complications related to the procedure were recorded. The mapping technique identified at least one SLN in 19/23 dogs, with a detection rate of 83%. The SLN did not correspond to the RLN in 52% of dogs. Multiple nodes were removed in 61% of dogs. At histopathology, eight (42%) dogs had SLN+, of which four differed from the RLN. Only minor self-limiting complications occurred in five (22%) dogs. Radiopharmaceutical and blue dye guidance is accurate (sensitivity 88.9%; specificity 100%) for SLNB in dogs with MHNT and cN0 and allowed the extirpation of unpredictable and/or multiple SLN with minimal morbidity. Incorporation of SLNB in the management of MHNT is desirable to correctly stage the cN0 neck, owing the unpredictability of the lymphatic drainage.

Comparative morphometry of the temporomandibular joint in brachycephalic and mesocephalic cats using multislice CT and cone beam CT.

OBJECTIVES: The purpose of this study was to analyse and compare morphometric measurements of the temporomandibular joint (TMJ) in two groups of cats with brachycephalic and mesocephalic craniofacial skull conformations using multislice CT and cone beam CT. METHODS: CT records of 20 cats without TMJ pathology were included in the study, and were divided into two groups according to those with mesocephalic or brachycephalic skull conformation. Width and depth of the mandibular fossa, width and height of the head of the mandible, and two different angles were measured in 40 TMJs. RESULTS: TMJ conformation differed between groups: 3/6 parameters were statistically different. Brachycephalic cats had a significantly narrower mandibular fossa, a shorter head of the mandible and a wider angle of congruence (angle 2). CONCLUSIONS AND RELEVANCE: The results provide morphometric measurements that can serve as a reference tool for the veterinary radiologist and surgeon when TMJ evaluation is necessary. Moreover, the study identified significant differences between the two craniofacial skull conformations.

Cardiopulmonary Resuscitation-associated Lung Edema (CRALE). A Translational Study.

Rationale: Cardiopulmonary resuscitation is the cornerstone of cardiac arrest (CA) treatment. However, lung injuries associated with it have been reported.Objectives: To assess 1) the presence and characteristics of lung abnormalities induced by cardiopulmonary resuscitation and 2) the role of mechanical and manual chest compression (CC) in its development.Methods: This translational study included 1) a porcine model of CA and cardiopulmonary resuscitation (n = 12) and 2) a multicenter cohort of patients with out-of-hospital CA undergoing mechanical or manual CC (n = 52). Lung computed tomography performed after resuscitation was assessed qualitatively and quantitatively along with respiratory mechanics and gas exchanges.Measurements and Main Results: The lung weight in the mechanical CC group was higher compared with the manual CC group in the experimental (431 ± 127 vs. 273 ± 66, P = 0.022) and clinical study (1,208 ± 630 vs. 837 ± 306, P = 0.006). The mechanical CC group showed significantly lower oxygenation (P = 0.043) and respiratory system compliance (P < 0.001) compared with the manual CC group in the experimental study. The variation of right atrial pressure was significantly higher in the mechanical compared with the manual CC group (54 ± 11 vs. 31 ± 6 mm Hg, P = 0.001) and significantly correlated with lung weight (r = 0.686, P = 0.026) and respiratory system compliance (r = -0.634, P = 0.027). Incidence of abnormal lung density was higher in patients treated with mechanical compared with manual CC (37% vs. 8%, P = 0.018).Conclusions: This study demonstrated the presence of cardiopulmonary resuscitation-associated lung edema in animals and in patients with out-of-hospital CA, which is more pronounced after mechanical as opposed to manual CC and correlates with higher swings of right atrial pressure during CC.

Characterization of skin surface and dermal microbiota in dogs with mast cell tumor.

The skin microbiota interacts with the host immune response to maintain the homeostasis. Changes in the skin microbiota are linked to the onset and the progression of several diseases, including tumors. We characterized the skin surface and dermal microbiota of 11 dogs affected by spontaneous mast cell tumor (MCT), using skin contralateral sites as intra-animal healthy controls. The microbial profile differed between healthy and tumor skin surfaces and dermis, demonstrating that the change in microbiota composition is related to the presence of MCT. The number of observed taxa between MCT and healthy skin surfaces was detected, showing a decrease in number and heterogeneity of taxa over the skin surface of MCT, at both inter- and intra-individual level. Preliminary data on bacterial population of MCT dermis, obtained only on three dogs, demonstrated an intra-individual reduction of taxa number when compared to the skin surface. Taxonomy reveals an increase of Firmicutes phylum and Corynebacteriaceae family in MCT skin surface when compared to the healthy contralateral. In conclusion, we demonstrate that microbial population of skin surface and dermis is related to mast cell tumor. Our study provides the basis for future investigations aiming to better define the interaction between mast cell tumors, microbiota and host immune response.

Computed tomographic appearance of canine tonsillar neoplasia: 14 cases.

The palatine tonsil is an uncommon site of oral canine neoplasia. For affected tonsils, squamous cell carcinoma is the most frequent type of neoplasia, followed by melanoma and lymphoma. Computed tomography (CT) is increasingly used for investigation of canine oropharyngeal pathology; however, limited information is available on the CT appearance of tonsillar neoplasms. Objectives of this retrospective descriptive case series were to characterize the CT features of canine tonsillar neoplasia and determine whether specific CT features differentiate nonneoplastic from neoplastic tonsils. Computed tomographic studies of 14 dogs diagnosed with tonsillar neoplasia were retrieved from two referral hospitals and reviewed by two observers. Diagnosis was based on histology or cytology. Carcinoma was diagnosed in 11 dogs, melanoma in two and lymphoma in one dog. Specific CT features of the tonsil and regional lymph nodes did not differentiate neoplastic from nonneoplastic tonsillar diseases, but regional lymph node CT features were useful for diagnosis in some cases. Marked enlargement (width ≥ 18 mm, 12/18), heterogeneity (16/18), and loss of the hypoattenuating hilus (18/18) of the medial retropharyngeal lymph node were common concomitant features of tonsillar neoplasia. The medial retropharyngeal and mandibular lymphadenomegaly was ipsilateral to the neoplastic tonsil in 8/12 and 6/9 dogs, respectively. Five dogs demonstrated little or no enlargement of the tonsil despite the associated metastatic lymphadenomegaly. Tonsillar neoplasia should therefore be considered as a differential diagnosis for dogs with CT evidence of isolated medial retropharyngeal lymphadenomegaly (regardless of normally sized tonsils), or of any enlarged tonsil with no associated lymphadenomegaly.

Dynamic tomographic studies of interscapular feline injection-site sarcoma: essential or useless practice?

Objectives Feline injection-site sarcomas (FISSs) are soft tissue tumours typically characterised by an interscapular location and highly infiltrative behaviour. CT is considered the modality of choice for FISS staging and double positioning (dynamic approach) was reported to successfully detect the exact extent of infiltration into the muscles. The aim of the present study was to investigate the utility of the dynamic approach in feline patients referred for preoperative staging of interscapular FISS. Methods Tumour volume estimates were compared between the ellipsoid and the semi-automated segmentation methods. Two radiologists blinded to the patient coding used images from each position to assess the extent of muscular infiltration. The distance between the neoplasm and the adjacent skeletal structures (scapulae, spinous processes) was recorded in both positions by a single radiologist. Results Fifty-nine of 84 neoplasms invaded the adjacent muscular structures, with up to 15 muscles infiltrated. Between the extended and flexed position the average estimated numbers of muscles infiltrated were 1.9 (extended) and 1.84 (flexed) for observer A and 1.89 (extended) and 1.85 (flexed) for observer B. Good agreement between observers was established, with higher tumour volumes detected via the ellipsoid method. Moreover, tumours with smaller volumes showed slightly decreased muscular infiltration. Marked difference in the recorded distance between the skeletal structures and the neoplasm in the two different positions was established (mean ± SD difference spinous processes: 9.74 ± 9.57 mm; mean ± SD difference scapulae: 15.15 ± 11.76 mm). Conclusions and relevance A dynamic approach should be used for a complete evaluation of the invasiveness of FISS along with appropriate methodology for tumour volume measurement, which could potentially alter the tomographic estimation of the real dimension of the neoplasms.

Calvaria and orbital metastases of pulmonary adenosquamous carcinoma in a cat: a diagnostic challenge.

An 11-year-old cat with a 4-month history of lethargy, inappetence, dysphagia, partial mandibular paralysis and weight loss, was euthanized due to the rapid deterioration of his condition. Post-mortem radiographic examination revealed severe bone lysis of the left zygomatic arch, temporal and parietal bones. Magnetic resonance imaging of the head showed a large isointense mass of the left side of the skull associated with extensive lysis of the parietal and temporal bones and destruction of the adjacent tympanic bulla. Gross and histological examinations revealed a pulmonary adenosquamous carcinoma of the left lung, with metastases to the spleen, liver, mesenteric lymph nodes, mesentery, diaphragm, abdominal aorta, left orbit and calvaria. No limb or digit metastases were detected.

Imaging diagnosis--split cord malformation.

The features of a calf with a split cord malformation are described. Clinically, there was severe cervicothoracic kyphoscoliosis and an interscapular dermal sinus associated with cerebrospinal fluid drainage. Using magnetic resonance imaging, complete duplication of the spinal cord at the cervical intumescence was detected. There was associated syringohydromyelia, multiple cervicothoracic vertebral malformations resulting in kyphoscoliosis and rachischisis, herniation of the cerebellar vermis, meningoencephalocele, and calvarial defects.

Spinal epidural abscess in two calves.

OBJECTIVE: To report clinical signs, diagnostic and surgical or necropsy findings, and outcome in 2 calves with spinal epidural abscess (SEA). STUDY DESIGN: Clinical report. ANIMALS: Calves (n=2). METHODS: Calves had neurologic examination, analysis and antimicrobial culture of cerebrospinal fluid (CSF), vertebral column radiographs, myelography, and in 1 calf, magnetic resonance imaging (MRI). A definitive diagnosis of SEA was confirmed by necropsy in 1 calf and during surgery and histologic examination of vertebral canal tissue in 1 calf. RESULTS: Clinical signs were difficulty in rising, ataxia, fever, apparent spinal pain, hypoesthesia, and paresis/plegia which appeared 15 days before admission. Calf 1 had pelvic limb weakness and difficulty standing and calf 2 had severe ataxia involving both thoracic and pelvic limbs. Extradural spinal cord compression was identified by myelography. SEA suspected in calf 1 with discospondylitis was confirmed at necropsy whereas calf 2 had MRI identification of the lesion and was successfully decompressed by laminectomy and SEA excision. Both calves had peripheral neutrophilia and calf 2 had neutrophilic pleocytosis in CSF. Bacteria were not isolated from CSF, from the surgical site or during necropsy. Calf 2 improved neurologically and had a good long-term outcome. CONCLUSION: Good outcome in a calf with SEA was obtained after adequate surgical decompression and antibiotic administration. CLINICAL RELEVANCE: SEA should be included in the list of possible causes of fever, apparent spinal pain, and signs of myelopathy in calves.