Comparison of a new immobilization method using a reusable 3-point fixation cylinder system and bite-block type immobilization methods in veterinary radiotherapy.

In veterinary radiotherapy, highly reproducible immobilization is important for accurate irradiation. Consequently, we developed a new reusable head-immobilization method for dogs using cylinders. This study aimed to compare the accuracy of our novel immobilization method using cylinders with that of bite-block type immobilization methods. Three immobilization methods were compared: bite-block only, bite-block combined with torso immobilization, and immobilization using cylinders. Five beagles with canine teeth underwent CT five times for each of the three immobilization methods. One beagle without canine teeth underwent CT 15 times using each method. Three maxillary landmarks (maxillary incisor, frontal sinus, and occipital bone) and one mandibular landmark (mandibular incisor) were established, and the errors in each immobilization method were measured. For all head landmarks, the error in the immobilization method using cylinders was the most reproducible, with the smallest errors. No significant differences were observed in the time required for immobilization. Although there were limitations (such as the use of dogs from a single breed, a single episode of anesthesia, no disassembly of the immobilization system between scans, and the same person performing the positioning on the same day), we found our new reusable immobilization method using cylinders was the most accurate among the three compared methods. This was a proof-of-principle study to evaluate head immobilization using cylinders, and further investigations are needed to confirm its clinical utility.

Recurrence analysis of intraoperative acridine orange-photodynamic therapy for dogs with intranasal tumors.

Intraoperative acridine orange-photodynamic therapy (AO-PDT) and cribriform plate irradiation are used to treat canine intranasal tumors. The purpose of this study was to evaluate the effects of AO-PDT on intranasal tumors and the recurrence rate of tumors after this treatment. Treatments with AO-PDT were performed on 38 dogs through a narrow window of the dorsal nasal cavity. The median progression-free interval was 12 mo and recurrence was detected in 21 dogs. Based on computed tomography, recurrence in 16 dogs was biased to the following areas: lateral (n = 10), medial (n = 2), ventral (n = 0), rostral (n = 0), and caudal (n = 8). Side effects were mild and included subcutaneous emphysema and rhinitis. The median survival time was 24 mo. Although AO-PDT with cribriform irradiation is an effective treatment for intranasal tumors, AO-PDT techniques should be improved to treat the nasal cavity more uniformly and thoroughly.

Analyse de récurrence de la thérapie photodynamique peropératoire à l'acridine orange pour des chiens atteints de tumeurs intranasales. La thérapie photodynamique peropératoire à l'acridine orange (AO-PDT) et l'irradiation de la plaque cribriforme sont utilisées pour traiter les tumeurs intranasales canines. Le but de cette étude était d'évaluer les effets de l'AO-PDT sur les tumeurs intranasales et le taux de récidive des tumeurs après ce traitement. Des traitements avec AO-PDT ont été effectués sur 38 chiens à travers une fenêtre étroite de la cavité nasale dorsale. L'intervalle médian sans progression était de 12 mois et une récidive a été détectée chez 21 chiens. Sur la base de la tomodensitométrie, la récidive chez 16 chiens était biaisée dans les zones suivantes : latérale (n = 10), médiale (n = 2), ventrale (n = 0), rostrale (n = 0) et caudale (n = 8). Les effets secondaires étaient légers et comprenaient l'emphysème sous-cutané et la rhinite. La durée médiane de survie était de 24 mois. Bien que l'AO-PDT avec irradiation de la plaque cribriforme soit un traitement efficace pour les tumeurs intranasales, les techniques d'AO-PDT devraient être améliorées pour traiter la cavité nasale de manière plus uniforme et plus complète.(Traduit par Dr Serge Messier).

Intraoperative acridine orange photodynamic therapy and cribriform electron-beam irradiation for canine intranasal carcinomas: 14 cases.

Canine intranasal carcinomas are almost always malignant. Surgery alone often results in rapid tumor regrowth. Radiotherapy is the treatment of choice for dogs with intranasal tumors. Here, we retrospectively assessed treatment of intranasal carcinoma by marginal tumor resection followed by intraoperative acridine orange (AO) photodynamic therapy (PDT) and cribriform plate electron-beam intraoperative radiotherapy (IORT). Fourteen canine cases were assessed, 12 of which had stage I tumors, one with stage III, and one with stage IV. Recurrence was detected in 8, with a median recurrence from the time of treatment of 6 months (range: 3 to 16 months). The median progression-free survival time and overall survival time after treatment were 13 and 22 months, respectively. Adverse events were mild. Marginal tumor resection followed by intraoperative AO-PDT and cribriform plate electron-beam IORT may increase the tumor control time in dogs with marginally resectable intranasal malignant tumors beyond that incurred by surgery alone.

Thérapie photodynamique peropératoire à l'acridine orange et irradiation par faisceau électrique pour carcinome intranasal canin : 14 cas. Un carcinome intranasal canin est presque toujours malin. Une simple opération chirurgicale résulte souvent dans la rapide réapparition de la tumeur. Dans cet article, nous discutons d'un traitement d'un carcinome intranasal par résection marginale de la tumeur effectué simultanément à une thérapie photodynamique (TPD) peropératoire à l'acridine orange (AO) et une radiothérapie peropératoire (RPO) par faisceau électrique des lames criblées. L'étude a porté sur quatorze cas chez le chien dont 12 tumeurs étaient classées au stade I, une au stade III et une au stade IV. Huit des cas étaient des cas de récidive selon une moyenne de 6 mois depuis la période du traitement (plage de 3 à 16 mois). Le temps de survie moyen à l'état stabilisé et le temps de survie général après traitement étaient respectivement de 13 et 22 mois. Les incidents thérapeutiques sont moindres (cinq cas d'emphysème sous-cutané et quatre cas de rhinite). La résection marginale de la tumeur conduite simultanément avec une TPD-AO peropératoire et une RPO par faisceau électrique des lames criblées semble permettre une plus longue phase de maîtrise des tumeurs chez le chien porteur d'une tumeur intranasale maligne à résection marginales possible par rapport aux résultats obtenus par simple intervention chirurgicale.(Traduit par les auteurs).

Suspected panosteitis in a crossbred calf.

A male crossbred calf developed a limp and pain upon deep pressure on the right hind limb and the right forelimb. The radiographic findings of affected limbs and pathological findings of bone biopsy were similar to those observed in canine panosteitis. This is the first case of suspected panosteitis reported in cattle.

Panostéite suspectée chez un veau de race croisée. Un veau mâle de race croisée a développé une boiterie et de la douleur à l'application d'une pression profonde sur la jambe arrière droite et la jambe avant droite. Les résultats de la radiographie des membres touchés et les résultats pathologiques d'une biopsie osseuse étaient semblables à ceux observés dans la panostéite canine. Il s'agit du premier cas de panostéite suspectée chez le bétail.(Traduit par Isabelle Vallières).

Availability and issues of 3D-printed skull models for veterinary anatomy laboratories from students' perspective before and during the COVID-19 pandemic.

Three-dimensional (3D)-printed models of bones are a convenient and durable alternative to real bone specimens, and they have been used in anatomy laboratories. It is necessary to identify the precise advantages of 3D-printed models from all perspectives; not only the improvement in students' knowledge of anatomy but also the students' assessment of such models. Here, students of veterinary medicine and animal science evaluated the reproducibility and effectiveness of 3D-printed models as a learning tool by completing our questionnaires, with a focus on their understanding of the skull-morphological differences among dog breeds. With the COVID-19 pandemic having obliged veterinary universities to provide courses online, we also investigated how the pandemic affected the students' evaluation of the 3D-printed models. The questionnaire results revealed that the animal science students were satisfied with the reproducibility of the 3D-printed models, but the veterinary students were not (they preferred to use real specimens). The skull differences were well understood by both types of students, indicating that 3D-printed models are effective for learning about rare skeletal specimens. The veterinary students who experienced the COVID-19 pandemic tended to choose real specimens more often than those who did not have this experience. Our results suggest that the use of 3D-printed models as an introduction and the use of real specimens in anatomy laboratory courses can be adequate for veterinary students. Together our findings suggest ways to improve the educational performance of 3D-printed models for veterinary students who need to understand the anatomy of many species.

Preclinical/clinical trials of thrice-weekly administration of a combination of tegafur/gimeracil/oteracil (TS-1) and toceranib phosphate in dogs with intranasal tumors.

Intranasal tumors in dogs are malignant solid tumors that are primarily treated with radiotherapy and often recur post-treatment. Combination therapy is pivotal in cancer therapy. Effective drugs include fluoropyrimidine 5-fluorouracil (5-FU) and toceranib phosphate. TS-1, an oral formulation containing the 5-FU prodrug tegafur and enzyme modulators gimeracil and oteracil, is proven to be safe in dogs with solid tumors. While the oral drug toceranib phosphate (Palladia®) is safely administered, the combined toxicity with TS-1 is unknown. We aimed to determine the dosage of this combination in dogs. In the preclinical/clinical trials conducted here, we used a standard 3+3 cohort design with fixed doses of toceranib phosphate (2.4 mg/kg) administered thrice weekly. TS-1 administration was initiated at a dose of 0.5 mg/kg (upper limit 2.0 mg/kg) thrice weekly. Four cohorts were included to confirm the safety of TS-1 and toceranib phosphate. Each cohort was followed up for 1 month. The intranasal tumor types included in the clinical trial (n=13) were adenocarcinoma (n=7), squamous cell carcinoma (n=1), non-epithelial malignancy (n=2), undifferentiated carcinoma (n=1), and transitional carcinoma (n=2). The TS-1 dosage could be increased up to its dose limit in the preclinical/clinical trials. The TS-1 dose to combine with toceranib phosphate thrice weekly was 2.0 mg/kg. This regimen was well-tolerated in dogs. Thus, combined TS-1 and toceranib phosphate therapy is safe for dogs with intranasal tumors.

Cor triatriatum sinister with dextrocardia in association with ostium secundum atrial septal defect, subpulmonary ventricular septal defect and bicuspid pulmonary valve in a pig.

Necropsy of a 52-day-old Camborough pig revealed numerous cardiac malformations. The positional relationship of the atria, ventricles and great vessels was a mirror image type (I, L and L): inverted arrangement of the atria, with a left-sided right atrium and right-sided left atrium (situs inversus); inverted arrangement of the ventricles, with a left-sided morphological right ventricle and right-sided morphological left ventricle (L-loop); and aortic valve to the front left relative to the pulmonary valve (L-malposed). The major malformations included an ostium secundum atrial septal defect, cor triatriatum sinister (CTS), a subpulmonary ventricular septal defect and a bicuspid pulmonary valve. Histological examination revealed myocyte hypertrophy, focal myocardial necrosis and calcification in the left morphological right ventricle of the heart. To the best of our knowledge, this is the first report of CTS in pigs. Although the individual malformations found in the present case are not unique, an unusual combination of these cardiac malformations has not been described in animals.

Screening of bacterial DNA in bile sampled from healthy dogs and dogs suffering from liver- or gallbladder-associated disease.

Although the biliary system is generally aseptic, gallbladder microbiota has been reported in humans and some animals apart from dogs. We screened and analyzed the bacterial deoxyribonucleic acid in canine gallbladders using bile sampled from 7 healthy dogs and 52 dogs with liver- or gallbladder-associated disease. PCR screening detected bacteria in 17.3% of diseased dogs (9/52) and none in healthy dogs. Microbiota analysis of PCR-positive samples showed that the microbial diversity differed between liver- and gallbladder-associated disease groups. Thus, a specific bacterial community appears to occur at a certain frequency in the bile of diseased dogs.

Serum concentration and safety of intravenous drip versus subcutaneous administration of carboplatin in dogs.

Carboplatin is used to treat certain cancers in dogs and cats and is routinely administered via intravenous drip (IVD). Subcutaneous (SC) administration has also been described. However, the toxicity, serum concentrations, and area under blood concentration-time curves (AUCs) of SC carboplatin are unknown. This study aimed to compare serum carboplatin concentrations in dogs after SC and IVD and to monitor any adverse events. In this crossover study, five dogs received SC or IV carboplatin (300 mg/m2). After a minimum of 3 weeks, each dog received the other treatment. No gross skin toxicity or abnormal clinical signs were observed in any of the dogs. Blood test abnormalities were detected in most dogs. Decreased neutrophil and platelet counts, and increased C-reactive protein (CRP) levels were found. There was no significant difference in the neutropenia, thrombocytopenia, and CRP scores between the groups. Systemic toxicities of SC carboplatin were comparable to those of IVD carboplatin. The time to maximum carboplatin concentration after SC was longer than that after IVD (P<0.001). SC carboplatin remained in the serum longer than IVD carboplatin (P=0.008). The AUC of SC was less than that of IVD (P=0.002). The AUC and time taken to reach the maximum concentration of SC carboplatin were lower than those of IVD carboplatin. This study suggests that SC carboplatin may be an efficacious option for the treatment of tumors in dogs, particularly where IVD administration is challenging.

Application of a novel carboxymethyl cellulose-based Mohs sol-gel on malignant wounds in three dogs.

The preparation of modified Mohs paste, commonly used for malignant wounds, requires time and effort. Moreover, metal-containing liquid waste is generated when malignant wounds are scrubbed. Therefore, we previously changed the base material of the modified Mohs paste from zinc oxide starch powder to carboxymethyl cellulose (CMC). The novel modified Mohs paste based on CMC (moM-CMC sol) may reduce these disadvantages. In the present study, the moM-CMC sol was applied to malignant tumors in three dogs to manage bleeding and malodor. The moM-CMC sol transitioned into a gel on the tumors within an hour of application and could be easily removed. The symptoms resolved in all cases. The moM-CMC sol could be beneficial for dogs with malignant wounds.

Safety of alternate-day treatment with TS-1TM (tegafur/gimeracil/oteracil) in tumor-bearing dogs: a pilot study.

Tegafur is a prodrug of fluoropyrimidine 5-fluorouracil (5-FU), while TS-1TM is an oral fixed-dose combination of three active drugs, tegafur, gimeracil, and oteracil. This pilot study evaluated the safety of tegafur/gimeracil/oteracil in the treatment of cancers in dogs. Tegafur/gimeracil/oteracil was administered orally at a mean dose of 1.1 mg/kg twice daily on alternate days, Monday-Wednesday-Friday, every week to 11 dogs with tumors. Partial response and stable disease were observed in one dog each, whereas six exhibited progressive disease. Three dogs were not assessed. Adverse events, the most serious being grade 2, were noted in seven dogs. Adverse events were acceptable, and the drug was effective in some dogs. Therefore, tegafur/gimeracil/oteracil may be useful for treating malignant solid tumors in canines.

Evaluation of the susceptibility artifacts and tissue injury caused by implanted microchips in dogs on 1.5 T magnetic resonance imaging.

Performing magnetic resonance imaging (MRI) in patients with a metallic implant raises concern over the potential complications, including susceptibility artifacts, implant migration, and heat injury. The purpose of this study was to investigate these complications in dogs with implanted microchips by evaluating MR images and the histopathological changes after 1.5 Tesla (T) MRI. Five dogs underwent microchip implantation in the cervicothoracic area. One month later, the area was imaged using 1.5T MRI in three dogs. The microchips were removed surgically together with the surrounding tissue in all dogs. There was significant signal loss and image distortion over a wide range around the area where the microchip was implanted. This change was consistent with susceptibility artifacts, which rendered the affected area including the spinal cord undiagnostic. The artifact was more extensive in T2*-weighted images (gradient-echo) and less extensive in proton density-weighted images (fast spin-echo with short echo time). Histopathologically, all microchips were well-encapsulated with granulation tissue, and there were no evidence of migration of microchips. Cell debris and a moderate number of degenerated cells with fibrin were seen in the inner layer of the granulation tissue in each dog that underwent MRI. These changes were very subtle and did not seem to be clinically significant. The results of this study suggest that, in 1.5T MRI, susceptibility artifacts produced by implanted microchips can be marked, although the dogs with implants appeared to be scanned safely.

Computed tomography of thoracic lymph nodes in 100 dogs with no abnormalities in the dominated area.

In dogs, reports on thoracic lymph nodes are lacking compared to abdominal lymph nodes. This report analyzed the position, number, size, shape, and homogeneity of thoracic lymph nodes (cranial sternal, cranial mediastinal, tracheobronchial, aortic thoracic, and pulmonary lymph nodes) using thoracic computed tomography (CT) images of 100 dogs without any lesions in the dominated areas of thoracic lymph nodes. The position and number of intrathoracic lymph nodes could be observed in CT, consistent with macroscopic anatomical studies. It was difficult to set a clinical index associated with size using CT scans. Image findings that indicated abnormalities, such as circular shapes and non-uniform, may be routinely found in dogs and may not be considered abnormal on CT scans.

Retrospective study of canine insulinomas: eight cases (2005-2008).

This retrospective study examined 8 cases of pathologically diagnosed insulinoma. Surgical intervention was performed in all cases, once insulinoma was suspected based on unique clinical signs, hypoglycemia, and/or findings on ultrasonography. At the same time, insulin and glucose concentrations were measured before surgery for clinical diagnosis. Although all cases displayed typical clinical signs and hypoglycemia, insulin concentrations varied with 3 of 8 cases showing levels within the reference interval. In addition, to confirm the reliability of measured values, we submitted serum samples from 4 cases to two commercial veterinary laboratories. Results differed considerably between laboratories, with no apparent correlations between the two. In Laboratory A, 3 of 4 cases were above the reference interval, and 1 case was in the middle of the reference interval. Conversely, in Laboratory B, 3 of 4 cases were above the reference interval, and 1 case was below the reference interval. Split decisions regarding the diagnosis of insulinoma were seen for 2 of the 4 cases.

Insulinoma with basal ganglion involvement detected by magnetic resonance imaging in a dog.

A West Highland White Terrier was brought to our veterinary hospital with the chief complaints of seizures and staggering gait. When cephalic Magnetic resonance imaging (MRI) was performed, a symmetrical lesion was found in the basal ganglion. Suspecting a metabolic disorder, an abdominal ultrasonography was performed, and a tumor was found in the pancreas. The pancreatic tumor was surgically removed based on suspicion that it had induced the brain damage. The resected tumor was histopathologically diagnosed as an insulinoma. After removal, recurrence of neurological symptoms was not observed. MRI 3 months post-operation showed a reduction in the size of the brain lesion. Consequently, the tumor was thought to have induced the lesion in the basal ganglion, and this was verified by MRI. This case was considered to be extremely rare.

Examination of the utility of a bite block-type head immobilization device in dogs and cats.

We examined the utility of a bite block-type head immobilization device, hereafter referred to as "head immobilization device", in order to improve the ease of immobilization and accuracy when performing radiotherapy for cranial tumors in animals. The head immobilization apparatus was a rectangular-shaped bite block-type device. We examined 55 cases in 46 dogs that underwent head CT scans between June 2005 and May 2006. The head immobilization device was used for 26 cases (immobilization group) and was not used for 29 cases (control group). Head stability was maintained in the control group by placing a towel under the head. We measured the angle of rotation of the xy, yz and xz planes for each group. The angles of rotation of the xy plane for the control and immobilization groups were 3.69 +/- 2.28 (mean +/- SD) and 1.39 +/- 1.50, respectively. The t-test demonstrated that the difference was statistically significant (p<0.001). These results indicate that there was reduced tilting to the left or right. We conclude that use of this head immobilization device was extremely easy and that it improved the accuracy of radiotherapy for cranial tumors in dogs and cats.

Feasibility of complete surgical ligation on 72 dogs with singular extrahepatic congenital portosystemic shunt based on portal pressure and comparison of intraoperative mesenteric portovenography.

The relation between complete or partial ligation of extrahepatic portosystemic shunting and intraoperative mesenteric portovenography (IMP) was evaluated in 72 canines. Of the 72 dogs, 55 had complete ligation and 17 underwent partial ligation of abnormal vessels. IMP allowed evaluation of the number of intrahepatic portal branches and ratio of the diameter of cranial (CrPV) and caudal main portal vein (CaPV) at the shunt location. Nearly all cases in the complete ligation group and nearly half of the cases in the partial ligation group had three or more portal vein branches. CrPV/CaPV was 0.75 ± 0.24 in the complete ligation group and 0.29 ± 0.15 in the partial ligation group. CrPV/CaPV can be an effective new method for assessing IMP.

Disseminated nontuberculous mycobacterial disease in a cat caused by Mycobacterium sp. strain MFM001.

Mycobacterium sp. strain MFM001 (MFM001), a new strain of slow-growing nontuberculous mycobacteria not associated with the Mycobacterium avium complex, led to disseminated mycobacterial disease characterized by transmural granulomatous gastroenterocolitis of lepromatous type in a cat treated with immunosuppressive medication. MFM001 was found to be closely related to M. kyorinense or M. celatum by partial sequence of 16S rDNA, and identical with an unspecified M. sp. strain B10-07.09.0206 isolated from a human pulmonary infection in Germany. MFM001 should be considered as a pathogenic organism in cats, especially in immunocompromised animals.

Hepatic AA amyloidosis in a cat: cytologic and histologic identification of AA amyloid in macrophages.

A 3-year-old, spayed female, Domestic Shorthair cat presented with anorexia, lethargy, vomiting, probable hemoabdomen, and multiple masses on the right lateral liver lobe. Clinicopathologic and imaging abnormalities included anemia, azotemia, icterus, and hepatomegaly with hypoechoic masses. On cytologic evaluation of a fine-needle aspiration of a liver mass there was abundant extracellular pink- to purple-colored material between hepatocytes. The amorphous material was stained with direct fast scarlet (DFS), and green birefringent areas were observed under polarized light, confirming the presence of amyloid. A unique finding on the cytologic smear were macrophages containing amorphous and fibrillar amyloid-like protein. Histopathologic examination using H&E and Congo red staining confirmed amyloid deposits within the space of Disse, along the sinusoids, portal tracts, blood vessel walls, and within the cytoplasm of macrophages. Immunohistochemical staining with anti-AA amyloid antibodies further confirmed the presence of AA amyloid. To the author's knowledge, this is the first report of the cytologic finding of AA amyloid protein within macrophages and DFS stain detection of amyloid on a cytologic smear.

Plasma concentration of vitamin C in dogs with a portosystemic shunt.

Most mammals, including dogs, synthesize vitamin C in the liver. We measured the plasma concentration of vitamin C to assess the body vitamin C status in 15 dogs with a portosystemic shunt (PSS). The plasma biochemical parameters indicated liver abnormalities in all the dogs. In contrast, the plasma concentration of vitamin C ranged from 2.21 to 9.03 mg/L in the 15 dogs and was below the reference range (3.2 to 8.9 mg/L) in only 2 dogs. These findings suggest that vitamin C status is not impaired in dogs with PSS.