Planar Lymphoscintigraphy for sentinel lymph node mapping in dogs with mast cell tumor: a pilot study.

The histopathological assessment of the first node receiving lymphatic drainage from a tumor – defined as Sentinel Lymph Node (SLN) – is essential to determine stage, therapy and outcome in oncological patients. Both in human and veterinary medicine, lymphoscintigraphy is a recognized procedure for SLN detection (Mariani et al., 2004; Tuohy et al., 2009; Beer et al., 2017). In this study, we want to determine the most suitable pre-operative planar lymphoscintigraphy protocol for SLN mapping in dogs with mast cell tumor (MCT). We selected 5 dogs diagnosed with cutaneous MTC, with clinically negative lymph nodes and no distant metastasis, undergoing surgical tumor removal, and we obtained owner’s written consent. Planar lymphoscintigraphy was performed in patients under general anesthesia, after subcutaneous peritumoral injection of different doses of technetium-99m (Tc-99m) labelled colloid diluted reaching a 0.5 ml volume (Worley, 2014). The MegaBecquerel value (MBq) of the syringe was measured before and after the injection. Dynamic images (1 frame/second for 60 seconds) were taken at the moment of the injection, 3 and 8 minutes after the injection. Ventrodorsal (VD) and lateral (L) static images (120 seconds/frame) were taken until the identification of SLN had been made. If needed, the injection site was masked with a 2-mm lead foil. Results are showed in Table 1. In patient 1, the SLN was not identify, probably due to a superimposition with the injection site. During the study, we increased the injected MBq dose, in order to better visualize lymphatic path and SLN (Balogh et al., 2002). In fact, the number of static images needed to identify SLN have been reduced from 8,7 to 6. Masking the injection site proved to be useful for a better visualization of SLN. Dynamic images showed to be unnecessary for the SLN identification. For further studies, we suggest the injection of minimum 23,5 MBq Tc-99m activity and the acquisition of VD and L static images with and without masking the injection site

Straight trajectory planning for keyhole neurosurgery in sheep with automatic brain structures segmentation

In a translational neuroscience/neurosurgery perspective, sheep are considered good candidates to study because of the similarity between their brain and the human one. Automatic planning systems for safe keyhole neurosurgery maximize the probe/catheter distance from vessels and risky structures. This work consists in the development of a trajectories planner for straight catheters placement intended to be used for investigating the drug diffusivity mechanisms in sheep brain. Automatic brain segmentation of gray matter, white matter and cerebrospinal fluid is achieved using an online available sheep atlas. Ventricles, midbrain and cerebellum segmentation have been also carried out. The veterinary surgeon is asked to select a target point within the white matter to be reached by the probe and to define an entry area on the brain cortex. To mitigate the risk of hemorrhage during the insertion process, which can prevent the success of the insertion procedure, the trajectory planner performs a curvature analysis of the brain cortex and wipes out from the poll of possible entry points the sulci, as part of brain cortex where superficial blood vessels are naturally located. A limited set of trajectories is then computed and presented to the surgeon, satisfying an optimality criteria based on a cost function which considers the distance from critical brain areas and the whole trajectory length. The planner proved to be effective in defining rectilinear trajectories accounting for the safety constraints determined by the brain morphology. It also demonstrated a short computational time and good capability in segmenting gyri and sulci surfaces

A case of adrenal tumour in a lion (Panthera leo): tomographic and ultrasonographic findings.

Adrenal gland tumors are common in humans and in several animal species. Studies concerning this neoplasia in human medicine indicate that clinical signs have a high variability. Adrenal adenomas can be occasionally observed in asymptomatic patients during tomographic studies while estrogen-secreting tumors, known as "feminizing adrenal tumors" (FATs), have been rarely reported. The aim of this study is to describe for the first time the Imaging findings of a captivity lion affected by a neoplastic secreting adrenal tumour. An 8 year-old male lion with progressive lack of secondary sex characteristics, disorexia and weight loss was referred to our Institution. The patient was chemically immobilized to undergo general clinical evaluation, hematologic, serum biochemical and hormonal profile, FIV and FeLV tests. Three months later a total body computed tomography and abdominal ultrasonography were performed. Liver and left adrenal lesions FNABs were performed. Imaging findings showed the presence of an extended expansive neoplastic lesion on the left adrenal gland (40x39x37 mm) with right adrenal gland atrophy. Generalized hepatopathy associated with a suspected intrahepatic cholestasis was confirmed by ultrasonography. Cytological evaluation ruled out the presence of neuroendocrine cells without malignancy evidences compatible with the adenomatous nature of the lesion, associated with moderate degenerative hepatopathy. Blood tests reported an estradiol concentration of 462 ng/dl. To our knowledge, this is the first description of adrenal mass in a lion associated with secondary feminization, inappetence and high values of hematic estradiol, referable to a feminizing adrenal tumor (FAT).

Sheep brain atlas creation. Diffusion tensor imaging and Scanning electron microscope in sheep brain analysis

IntroductionsAim of EDEN 2020 project is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model.For surgical planning purpose a Diffusion Tensor Imaging (DTI) of white matter tracts in the sheep is necessary to identify the target points useful for the catheter introduction.The analysis of the sheep brain under a Scanning Electron Microscope (SEM) is required to understand any alterations due to the catheter introduction and to fluids injection during CED administration. Materials and methodsAnimals were treated in accordance with the European Communities Council directive (86/609/EEC), to the laws and regulations on animal welfare enclosed in D.L.G.S. 26/2014A total of five 70 kg female, one year old, sheep were used for the study.All animals, under general anesthesia, underwent to Magnetic Resonance Imaging (MRI) acquisition. MRI scanner used was Philips Ingenia 1.5 Tesla system.Once the DTI imaging were acquired the animals were euthanased, sheep brain was collected and samples of white matter tracts obtained with disposable biopsy punches of 1.5-2 mm of diameter.The samples were fixed, stained in Osmium tetroxide (OsO4) and then embedded with two different protocols (cold curing vs thermal curing) in resin for the Focused Ion Beam (FIB) SEM analyses. Results and discussionAll the DTI images were uploaded to TrackVis software and major white matter fiber tracts analysed. Corticospinal tract, visual radiation, fornix and fronto-occipital fasciculus were identified.Corticospinal tract was identified as major white matter tract in sheep brain and useful as target area for the research aims.For the SEM analysis the thermal protocol was recognised as better curing methods for the research purpose than cold curing one. ConclusionThe data acquired in this study are still submitted to analysis. AcknowledgmentThe project has received funding from the European Union’s EU Research and Innovation programme Horizon 2020 (no 688279)

Peribulbar block in equine isolated heads. Development of a single needle technique and tomographic evaluation

Peribulbar block (PPB) has been used in humans as a safer alternative to retrobulbar block (RBB). PBB, depends on the diffusion of anaesthetic solution into the muscle across the connective tissue and it is performed introducing the needle within the extraconal space. The advantages are fewer complications and palpebral akinesia. In Veterinary Medicine few studies describe this technique in dogs (Ahn J 2013) and cats (Shilo-Benjamini et al. 2013). Based on literature the aim of the study is to determinate, in equine specimens, feasibility of inferior PBB with single needle injection, by using contrast medium (CM), and to evaluate thought Computed Tomography (CT) the distribution around the optic nerve (degrees). PBB was performed in 6 orbits. The mixture injected consisted of 20 ml of physiological solution and iodinated CM at 25%. Each periorbital area underwent three CT scans. A basal acquisition to assess the needle position before the injection, a second and third scan were performed immediately after injection, and after application of pressure on the periorbital surface area to promote CM diffusion. The needle position was measured from the tip to the optic nerve with a mean distance of 2,27 mm ± 0,28. The mean volume distribution before pressure application was 23,56 cm3 ± 2,58 and after pressure application was 27,56 cm3 ± 4,8.  The CM distribution, was defined (Nouvellon et al. 2010) “successful” in 4 orbits (>270°) and “inadequate” in 2 orbits (<180°). The present study demonstrates feasibility of inferior PBB by single injection in horses for its simple and practical execution. Inferior PPB is a potential alternative to systemic administration of neuromuscular blocking agents for ophthalmic surgery. However, this approach needs to be evaluate in clinical trials to assess its feasibility and effectiveness in clinical practice for standing procedures

Helical Hydro-Computed Tomography in the diagnosis of pyloric stenosis in two foals

Pyloric stenosis is rarely reported in horses (Bart et al 1980; Bezdecova et al. 2009). Congenital and acquired conditions have been described (Church et al 1986; Heidmann et al 2004; Laing et al. 1992; McGill et al. 1984) clinical suspicion is based on clinical findings while definitive diagnosis is reached by exploratory laparotomy and gastroscopy. The use of other diagnostic techniques has never been described. Two foals were admitted for recurrent abdominal pain. Clinical and ultrasonographic (US) examinations were performed.  Foals underwent Computed Tomography (CT) of the abdomen, both native and Helical Hydro-CT. US revealed mild stomach distension, mild small bowel wall thickening; small intestine obstruction was suspected in both foals. Case 1, two-month old Thoroughbred filly 130 kg of weight: CT showed segmental concentric pylorus stenosis, at the pyloric duodenal junction level. Mild liquid distension of the pyloric antrum and mixed gas and fluid distension of the cranial duodenum. During necroscopy the pyloric antrum showed stenosis due to an inelastic constricting ring reducing the lumen of the pyloric canal. The glandular part presented mild acute catarrhal gastritis. Case 2, three-month old Italian Saddle colt 142 kg of weigh: CT showed small amount of intraluminal hyperattenuanting material within the gastric fundus and duodenum. Hydro-CT highlighted the presence of mild pylorus narrowing, mild distension and moderate mucosal irregularities of the pyloric antrum. An acquired pyloric stenosis secondary to chronic gastritis of unknown origin was suspected. Explorative laparotomy was performed; the antrum was mildly distended and the pylorus appeared narrowed and hard on palpation; gastrojejunostomy was performed. Ante-mortem diagnosis of pyloric stenosis in horses is challenging because aspecific clinical signs. Native CT allowed to investigate both the stomach and the small intestine and, in one case, outlined the presence of pylorus stenosis. In case 2, only Helical Hydro-CT allowed better evaluation of the pyloric thickness. CT and Helical Hydro-CT can be considered a useful diagnostic tool in foal with clinical suspicion of pyloric stenosis.

A rare case of pituitary chromophobe carcinoma in a dog: clinical, tomographic and histopathological findings

A 9 year old male mixed-breed dog was presented for progressive aggressiveness towards the owner. The neurological evaluation was consistent with a forebrain syndrome. Magnetic Resonance Imaging (MRI) of the brain revealed enlargement of the third ventricle and presence of a large spheroidal neoplasm in the sellar/parasellar region suggestive of a pituitary macroadenoma. On the owner request, the dog was euthanized. Histopathological examination revealed the presence of a pituitary chromophobe carcinoma. To the author’s knowledge, pituitary carcinomas have been rarely described in dogs, especially the chromophobe subtype

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

Simple summary Suture exostosis is a condition affecting the horse's head. The connections between the bone plates that form the horse's face have been shown to react to insult. Horses will then develop a swelling along the face that may be painful. Little is known about this condition and the present research project aimed to investigate horses presented to equine clinics with symptoms of the disorder. It was revealed that the condition can form following trauma, underlying sinus disease, following a surgery or without any apparent cause. Various treatment options to resolve the condition have been reported and the outcomes of those are described in the paper. Most consistently the proper diagnosis and identification and removal of potential bone sequestra are crucial for a timely resolution. 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

Non-invasive estimation of in vivo optical properties and hemodynamic parameters of domestic animals: a preliminary study on horses, dogs, and sheep

Biosensors applied in veterinary medicine serve as a noninvasive method to determine the health status of animals and, indirectly, their level of welfare. Near infrared spectroscopy (NIRS) has been suggested as a technology with this application. This study presents preliminary in vivo time domain NIRS measurements of optical properties (absorption coefficient, reduced scattering coefficient, and differential pathlength factor) and hemodynamic parameters (concentration of oxygenated hemoglobin, deoxygenated hemoglobin, total hemoglobin, and tissue oxygen saturation) of tissue domestic animals, specifically of skeletal muscle (4 dogs and 6 horses) and head (4 dogs and 19 sheep). The results suggest that TD NIRS in vivo measurements on domestic animals are feasible, and reveal significant variations in the optical and hemodynamic properties among tissue types and species. In horses the different optical and hemodynamic properties of the measured muscles can be attributed to the presence of a thicker adipose layer over the muscle in the Longissimus Dorsi and in the Gluteus Superficialis as compared to the Triceps Brachii. In dogs the absorption coefficient is higher in the head (temporalis musculature) than in skeletal muscles. The smaller absorption coefficient for the head of the sheep as compared to the head of dogs may suggest that in sheep we are indeed reaching the brain cortex while in dog light penetration can be hindered by the strongly absorbing muscle covering the cranium