The trigeminal nerve is responsible for innervating the periorbita. Ultrasound-guided trigeminal block is employed in humans for trigeminal neuralgia or periorbital surgery. There are no studies evaluating this block in dogs. This study aims to evaluate and compare two approaches (coronoid and temporal) of the trigeminal nerve block. We hypothesised superior staining with the coronoid approach. Thirteen dog heads were used. After a preliminary anatomical study, two ultrasound-guided injections per head (right and left, coronoid and temporal approach, randomly assigned), with an injectate volume of 0.15 mL cm⁻¹ of cranial length, were performed (iodinated contrast and tissue dye mixture). The ultrasound probe was placed over the temporal region, visualising the pterygopalatine fossa. For the temporal approach, the needle was advanced from the medial aspect of the temporal region in a dorsoventral direction. For the coronoid approach, it was advanced ventral to the zygomatic arch in a lateromedial direction. CT scans and dissections were conducted to assess and compare the position of the needle, the spread of the injectate, and nerve staining. No significant differences were found. Both approaches demonstrated the effective interfascial distribution of the injectate, with some minimal intracranial spread. Although the coronoid approach did not yield superior staining as hypothesised, it presents a viable alternative to the temporal approach. Studies in live animals are warranted to evaluate clinical efficacy and safety.

Introduction: Spectral detector Computed Tomography (SDCT) enables generation of virtual non-contrast (VNC) images derived from a post-contrast scan, as previously investigated in healthy dogs. This technique is especially promising for awake scanned rabbits where motion between the pre- and the post-contrast scans makes comparison challenging. This study aimed to determine the reliability of VNC images for assessing abdominal organs in 20 rabbits by evaluating their qualitative and quantitative parameters compared to true unenhanced (TUE) images. Our hypothesis were that the VNC series would be comparable to TUE series and that the quality of the VNC images would be equal to or even superior to the native images.Methods: Attenuation values of VNC and TUE series were assessed using a two one-sided t-test (TOST) and the signal-to-noise ratio was calculated for each ROI in the different series. Additionally, a qualitative assessment of the VNC images relative to TUE images was performed in consensus by a board-certified radiologist and a second year diagnostic imaging resident by evaluating the iodine subtraction, image quality and noise of VNC images based on a 5-point Likert scale.Results: A total of 219 regions of interest (ROIs) where drawn in abdominal organs. 72.1% of the ROIs displayed differences of less than 15 Hounsfield Units (HU) between TUE and VNC images. The differences in attenuation values of TUE and VNC were statistically significant (p < 0.05) for ≤ 5 HU in the spleen, for ≤ 10 HU and ≤ 15 HU additionally in the liver, musculature and renal cortices. These findings support the equivalence between VNC and TUE images. An average score of 4.4 was achieved for iodine subtraction across all patients, which encompasses all organ values, with no individual patient scoring below 4.0.Discussion: VNC images present a promising alternative to TUE images for abdominal organs without pathology in rabbits with the benefit of eliminating motion between the compared series and reducing examination time and radiation exposure by replacing pre-contrast scans. Further research is necessary to demonstrate the applicability of the technique to morphologically diseased organs.

The trigeminal nerve is responsible for innervating the periorbita. Ultrasound-guided trigeminal block is employed in humans for trigeminal neuralgia or periorbital surgery. There are no studies evaluating this block in dogs. This study aims to evaluate and compare two approaches (coronoid and temporal) of the trigeminal nerve block. We hypothesized superior staining with the coronoid approach. Thirteen dog heads were used. After a preliminary anatomical study, two ultrasound-guided injections per head (right and left, coronoid and temporal approach, randomly assigned), with an injectate volume of 0.15 mL cm-1 of cranial length were performed (iodate contrast and tissue dye mixture). The ultrasound probe was placed over the temporal region, visualizing the pterygopalatine fossa. For the temporal approach, the needle was advanced from the medial aspect of the temporal region in a dorsoventral direction. For the coronoid approach, it was advanced ventral to the zygomatic arch in a lateromedial direction. CT scans and dissections were conducted to assess and compare the position of the needle, spread of injectate, and nerve staining. No significant differences were found. Both approaches demonstrated effective interfascial distribution of injectate, with some minimal intracranial spread. Although the coronoid approach did not yield superior staining as hypothesized, it presents a viable alternative to the temporal approach. Studies in live animals are warranted to evaluate clinical efficacy and safety.

Background: Four studies investigated the efficacy of fluralaner/moxidectin/pyrantel chewable tablets (Bravecto® TriUNO) in preventing and treating canine angiostrongylosis; one study also included a formulation of fluralaner/milbemycin oxime. Methods: Studies included eight or 10 dogs/group. In Studies 1 and 2 (prevention), dogs inoculated with third-stage larvae of Angiostrongylus vasorum on day − 31 or − 28 were randomized to groups by sex and body weight; in Studies 3 and 4 (treatment) by faecal first-stage larvae counts at approximately 8 weeks post-inoculation (PI). All studies included an untreated control group (CG). Study 1 included three groups treated with formulations of moxidectin/fluralaner/pyrantel; minimum moxidectin doses 0.0125, 0.025 or 0.055 mg/kg. The formulation with moxidectin at 0.025 mg/kg, 99.0% effective in preventing establishment of infection, was adopted as the investigational veterinary product (IVP) for the following studies. Study 2 included a group treated with either the IVP or a combination of fluralaner (10 mg/kg) with milbemycin oxime (0.75 mg/kg) (IVP-2). In all studies, the IVP was administered once on day 0; in Study 2, IVP-2 was administered on days 0, 31, 62 and 93. In Study 1, efficacy was determined by reductions in geometric mean necropsy worm counts approximately 33 days post-treatment versus mean CG counts, in the other studies by reductions in mean faecal L1 counts. Study 2 assessed pulmonary changes via thoracic computed tomography. Respiratory signs and serological antibody responses were monitored. Results: In Study 1, all moxidectin doses exceeded 90% efficacy. In Study 2, IVP efficacy (one treatment) at 62 days was 100.0%; IVP-2 (four treatments) efficacy was 99.8% at 124 days. Respiratory signs were absent or lower in IVP-treated than CG dogs. In Studies 3 and 4, IVP efficacy was 100% by 3 and 4 weeks post-treatment, respectively. In all studies, lungworm count reductions in the IVP groups were statistically significant ( P < 0.0001) versus the CG. Serology confirmed A. vasorum infections in all control and IVP-2-treated dogs, and absence of infections in IVP-treated dogs. Treatments were well tolerated. Conclusions: A single treatment with Bravecto TriUNO is highly effective in preventing angiostrongylosis and eliminating established A. vasorum infections. Infection-related lung pathology was reduced in treated dogs.