Anatomical classification of feline congenital extrahepatic portosystemic shunts based on CT angiography: A SVSTS and VIRIES multi-institutional study in 231 cats.

The prevalence of anatomical-based subtypes of feline congenital extrahepatic portosystemic shunts (EHPSS) has not been completely elucidated. The goal of this study was to use CT angiography to create an anatomical-based nomenclature system for feline congenital EHPSS. Additionally, subjective portal perfusion scores were generated to determine if intrinsic portal vein development was associated with different shunt conformations or patient age at the time of CT. The SVSTS and VIRIES list services were used to recruit cases. Data collected included patient DOB, gender, breed, weight, CT date, and reported diagnosis. Shunts were classified based upon (1) the shunt portal vessel(s) of origin, (2) the shunt systemic vessel(s) of insertion, and (3) any substantial portal vessels contributing to the shunt. Additionally, hepatic portal perfusion was subjectively scored between 1 (poor/none) and 5 (good/normal) based on the caliber of the intrahepatic PVs. A total of 264 CT scans were submitted from 29 institutions. Due to exclusion criteria, 33 (13%) were removed, leaving 231 CT scans to be included. Twenty-five different EHPSS anatomies were identified with five classifications accounting for 78% of all shunts (LGP [53%], LGC-post [11%], LCG [7%], LGC-pre [4%], and PC [4%]). Shunt origin involved the left gastric vein in 75% of the described classifications. Significant differences were identified among the five most common shunt types with respect to age at the time of CT scan (P = .002), breed (P < .001), and subjective portal perfusion score (P < .001). This refined anatomical classification system for feline EHPSS may enable improved understanding, treatment comparisons, and outcome prediction for cats with these anomalies.

Diagnostic imaging descriptions and prevalence of presumed phrenic lymph nodes in dogs.

The phrenic lymph node (PLN) has been described in bovine, equine, and feline anatomic references but descriptions in canine anatomic references are currently lacking. Authors have observed a well-defined, soft tissue attenuating, contrast-enhancing structure in a location consistent with previous anatomic descriptions of the PLN in dogs that underwent thoracic CT for neoplastic staging. The aims of this two-part, retrospective/prospective, anatomic, prevalence study were (1) to describe the presence of a soft tissue structure close to the thoracic caudal vena cava, defined as the presumed PLN, in a series of dogs that underwent CT as part of the staging for metastatic disease; (2) to confirm the lymphatic origin of the presumed PLN in a dog through postmortem examination; (3) to assess the prevalence of the presumed PLN in a population of dogs that underwent thoracic CT or MRI for different clinical purposes; and (4) to assess the possibility to visualize the presumed PLN with ultrasonography. The lymphatic origin of the presumed PLN was confirmed by postmortem examination in one dog. The presumed PLN was visible in 29 of 777 canine CT examinations (prevalence 3.7%). The presumed PLN was not visible in 9 of 10 prospectively recruited ultrasound cases. Most dogs with visible presumed PLNs were large-medium breeds that were presented for neoplastic staging purposes. Findings indicated that a structure consistent with the previously reported anatomic features of PLN in cattle, horses, and cats may be detected with a low prevalence in canine CT and MRI examinations.

Dogs with congenital extrahepatic portosystemic shunts that have persistent shunting after surgery have a higher prevalence of urolithiasis.

OBJECTIVE: To report the presence of urolithiasis in dogs long-term after gradual attenuation of congenital extrahepatic portosystemic shunts (cEHPSS). ANIMALS: 25 client-owned dogs that underwent gradual attenuation of a cEHPSS, of which 19 had a closed cEHPSS and 6 developed multiple acquired portosystemic shunts (MAPSS) following surgery. PROCEDURES: A retrospective study with prospective follow-up was performed. Dogs that underwent cEHPSS surgery and had their postoperative cEHPSS status determined by transsplenic portal scintigraphy or CT angiography 3 months postoperatively were prospectively contacted and invited for a long-term follow-up visit (a minimum of 6 months postoperatively). Retrospective data were collected, and during the prospective follow-up visit a thorough history, blood tests and urinalysis, and ultrasonography of the urinary tract were performed to assess the presence of urinary signs and urolithiasis. RESULTS: Of 25 included dogs, 1 of 19 (5%) dogs with closed cEHPSS and 4 of 6 (67%) dogs with MAPSS had urolithiasis at long-term follow-up. Three (50%) dogs with MAPSS developed new uroliths. Long-term, dogs with closed cEHPSS that initially presented with and without urolithiasis had significantly less urolithiasis compared to dogs with MAPSS (P = .013 and P = .010, respectively). In the 4 dogs with closed cEHPSS that initially presented with nephrolithiasis, nephroliths became smaller or were no longer visible at the long-term follow-up visit. CLINICAL RELEVANCE: Dogs that developed MAPSS following cEHPSS surgery are at greater risk of urolithiasis compared to those with closed cEHPSS. Furthermore, ammonium urate uroliths might dissolve if portosystemic shunting ceases to exist.

CT features of primary bone neoplasia of the thoracic wall in dogs.

Primary thoracic wall neoplasia is uncommon in dogs and the prognosis depends on tumor type. The aims of this retrospective, multi-center, observational study were to describe CT features of primary thoracic wall neoplasia in dogs and to test the hypothesis that CT features would differ among tumor types. Dogs with a diagnosis of primary thoracic wall bone neoplasia and thoracic CT study were included. CT findings recorded were as follows: dimensions, location, invasiveness, grade and type of mineral attenuation, periosteal reaction, contrast enhancement, and presence of presumed pulmonary metastases, pleural effusion, and sternal lymphadenopathy. Fifty-eight cases were included (54 ribs and four sternum). Fifty-six were malignant (sarcomas - SARC) and two were benign (chondromas - CHO). Out of the 56 malignant tumors, 41 had histological confirmation of the tumor type: 23 (56%) osteosarcomas (OSA), 10 (24%) chondrosarcomas (CSA), and eight (20%) hemangiosarcomas (HSA). The majority of rib tumors were right-sided (59%) and ventrally located (72%). Malignant masses showed severe invasiveness, mild/moderate contrast enhancement, and different grades of mineral attenuation. Sternal lymphadenopathy was significantly more frequent in dogs with OSA and HSA compared to dogs with CSA (p = 0.004 and p = 0.023). Dogs with HSA showed significantly lower mineral attenuation grades compared to dogs with OSA (p = 0.043). Primary thoracic wall bone neoplasias were more frequently arising from the ribs, with only a few cases of sternal masses. Findings can be used to help prioritize differential diagnoses for CT studies of dogs with thoracic wall neoplasia.

CT Characteristics of the Thymus in Adult Dogs with Non-Thymic Neoplasia Compared to Young Dogs.

The thymus is a lymphatic mediastinal organ that is largely subject to changes with age. In human patients, the CT characteristics of the thymus in children and adults is well described. Furthermore, it is known in human medicine that stress can lead to a reduction in the size of the thymus, followed by a phase of hyperplasia (called the 'rebound effect'). The visualization of thymic tissue in the cranial mediastinum of adult dogs with neoplasia is possible and could be related to a similar effect. In this study, we aimed to describe the CT characteristics of the thymus in adult dogs with neoplasia and to compare the aspect of the thymus in these dogs to juvenile dogs with a presumed normal thymus. A total of 11 adult dogs with neoplasia and 20 juvenile dogs were included. Several CT features of the thymus were evaluated, including the size, shape, and pre- and post-contrast attenuation values. The overall appearance was lobulated in all of the adult dogs and homogeneous in all of the juvenile dogs; it was left-sided in all of the adult dogs, while it was located in the midline in a few of the juvenile dogs (right-sided only in one). The thymus was less attenuating in adult dogs, in some cases with negative minimum pre-contrast attenuation values. In some dogs with neoplasia, the thymus can be detected at CT examination despite their age.

Comparison of urethral length and orifice diameter in cats undergoing transpelvic or subpubic urethrostomy for perineal urethrostomy revision (cadaveric study).

OBJECTIVES: Stenosis is a postoperative complication reported in 12-17% of male cats that undergo perineal urethrostomy (PU). This study compared two different revision techniques for failed perineal urethrostomies. The first objective was to evaluate the feasibility of performing a transpelvic urethrostomy (TPU) after a previous, correctly performed PU in male cats. The second objective was to determine the residual urethral length, orifice diameter, and the position of the orifice relative to the pubic brim and anus after PU, TPU and subpubic urethrostomy (SPU). METHODS: Twenty male cat cadavers were randomly divided into two groups: TPU and SPU. In group TPU, PU was followed by TPU; in group SPU, PU was followed by SPU. After each procedure, the urethral orifice cross-section size was estimated by inserting the largest possible urinary catheter without resistance. Residual urethral length was measured both on contrast radiographs and after anatomical dissection. RESULTS: In all cats, TPU could be performed following a technically correct PU. The TPU resulted in a 1.5-times longer residual urethral length than SPU, based on contrast radiographs (P = 0.001) and confirmed by anatomical dissection (P <0.001). Relative to the initial urethral length, PU, TPU and SPU resulted in a reduction of 24%, 36% and 56%, respectively. The urethral orifice diameter after TPU did not differ from SPU (P = 1.000), and it was not statistically significantly different between TPU and PU (P = 0.317) or between SPU and PU (P = 0.655). The urethral orifice was located further away from the pubis (P <0.001) and closer to the anus (P <0.001) after TPU than after SPU. CONCLUSIONS AND RELEVANCE: Both TPU and SPU are possible revision surgeries following PU. As TPU preserves a significantly longer urethral length and requires less tissue dissection, the risk of urinary tract infections, urinary dermatitis and urinary incontinence might be less following TPU than SPU.

Scapular morphology of great apes and humans: A three-dimensional computed tomography-based comparative study.

The primate scapula has been studied widely since its shape has been shown to correlate with how the forelimb is used in daily activities. In this study, we expand on the existing literature and use an image-based methodology that was originally developed for orthopaedic practice to quantify and compare the three-dimensional (3D) morphology of the scapula across humans and great apes. We expect that this image-based approach will allow us to identify differences between great apes and humans that can be related to differences in mobility and loading regime of the shoulder. We hypothesize that gorillas and chimpanzees will have a similar scapular morphology, geared towards stability and weight-bearing in knuckle-walking, whilst the scapular morphology of orangutans is expected to be more similar to that of humans given their high glenohumeral mobility associated with their suspensory lifestyle. We made 3D reconstructions of computed tomography scans of 69 scapulae from four hominid genera (Pongo, Gorilla, Pan and Homo). On these 3D bone meshes, the inferior glenoid plane was determined, and subsequently, a set of bony landmarks on the scapular body, coracoid, and acromion were defined. These landmarks allowed us to measure a set of functionally relevant angles which represent acromial overhang, subacromial space and coracoacromial space. The angles that were measured are: the delto-fulcral triangle (DFT), comprising the alpha, beta, and delta angle, the acromion-glenoid angle (AGA), the coracoid-glenoid centre-posterior acromial angle (CGA), the anterior tilt (TA CGA) and the posterior tilt of the CGA (PT CGA). Three observers placed the landmarks on the 3D bone meshes, allowing us to calculate the inter-observer error. The main differences in the DFT were found between humans and the great apes, with small differences between the great apes. The DFT of humans was significantly lower compared to that of the great apes, with the smallest alpha (32.7°), smallest delta (45.7°) and highest beta angle (101.6°) of all genera. The DFT of chimpanzees was significantly higher compared to that of humans (p < 0.01), with a larger alpha (37.6°) and delta angle (54.5°) and smaller beta angle (87.9°). The mean AGA of humans (59.1°) was significantly smaller (p < 0.001) than that of gorillas (68.8°). The mean CGA of humans (110.1°) was significantly higher (p < 0.001) than in orangutans (92.9°). Humans and gorillas showed mainly a posterior tilt of their coracoacromial complex whilst chimpanzees showed mainly an anterior tilt. The coracoacromial complex of the orangutans was not tilted anteriorly or posteriorly. With our image-based method, we were able to identify morphological features of the scapula that differed significantly between hominid genera. However, we did not find an overall dichotomy in scapular morphology geared towards high stability (Pan/Gorilla) or high mobility (Homo/Pongo). Further research is needed to investigate the functional implications of these differences in scapular morphology.

Intra- and Inter-Observer Variability of Quantitative Parameters Used in Contrast-Enhanced Ultrasound of Kidneys of Healthy Cats.

Contrast-enhanced ultrasound (CEUS) is a non-invasive imaging technique which allows qualitative and quantitative assessment of tissue perfusion. Although CEUS offers numerous advantages, a major challenge remains the variability in tissue perfusion quantification. This study aimed to assess intra- and inter-observer variability for quantification of renal perfusion. Two observers with different levels of expertise performed a quantitative analysis of 36 renal CEUS studies, twice. The CEUS data were collected from 12 healthy cats at 3 different time points with a 7-day interval. The inter- and intra-observer agreement was assessed by the intraclass correlation coefficient. Within and between observers, a good agreement was demonstrated for intensity-related parameters in the cortex, medulla, and interlobular artery. For some parameters, ICCinter was considerably lower than ICCintra, mostly when the ROI encompassed the entire kidney or medulla. With the exception of time to peak (TTP) and mean transit time (mTTI), time-related and slope-related parameters showed poor agreement among observers. In conclusion, it may be advised against having the quantitative assessment of renal perfusion performed by different observers, especially if their experience levels differ. The cortical mTTI seemed to be the most appropriate parameter as it showed a favorable inter-observer agreement and inter-period agreement.

Sternal lymphadenopathy in dogs with malignancy in different localizations: A CT retrospective study of 60 cases.

Sternal lymph nodes (SLNs) drain a multitude of regions in dogs, including the pectoral and shoulder region, the thoracic wall and mammary glands, the mediastinum, thymus, diaphragm, and the ventral abdominal wall and peritoneal cavity. Neoplastic conditions of these regions can lead to sternal lymphadenopathy. The aim of this study was to assess the most frequent localizations of the primary neoplasia and the most frequent tumor types in dogs with sternal lymphadenopathy. Computed tomographic (CT) characteristics of SLNs in dogs with confirmed neoplasia were also described. For this single-center retrospective descriptive study, dogs with sternal lymphadenopathy and cytological or histological diagnosis of neoplasia were included. Sixty dogs fulfilled the inclusion criteria: 30 (50%) with thoracic neoplasia, 19 (32%) with abdominal neoplasia, 6 (10%) with neoplasia of the front limbs and 5 (8%) with generalized neoplasia. Based on the cytological/histological diagnosis of the primary neoplasia, 31/60 (52%) dogs presented with a sarcoma, 15/60 (25%) with carcinoma, and 14/60 (23%) with round cell tumor. The presence of heterogeneous contrast enhancement was more frequent in dogs with sarcoma, while the concomitant presence of other abnormal lymph nodes was more frequent in dogs with round cell neoplasia. Tumors of different types and in different location can result in sternal lymphadenopathy in dogs. The most frequent in this study were thoracic and abdominal neoplasia, followed by neoplasia of the shoulder region. Sarcoma was the most common tumor type detected in this study, and the main CT characteristic of the SLNs in case of sarcoma was heterogeneous contrast enhancement.

Shear wave elastography measurements in dogs treated surgically for congenital extrahepatic portosystemic shunts.

Assessing the postoperative surgical success of congenital extrahepatic portosystemic shunt (EHPSS) attenuation can be challenging and involve invasive imaging methods. Elastography is an ultrasound technique that allows qualitative and quantitative estimation of tissue stiffness and has extensively been used in people with liver disease. In recent years, increased interest in this technique has developed in veterinary medicine due to its non-invasive nature, availability, and low cost. The objective of this study was to compare liver stiffness values between dogs with closed EHPSS and those with multiple acquired portosystemic shunts (MAPSS) after gradual surgical attenuation and to assess whether shear wave elastography could be used to determine EHPSS closure. As a secondary objective, measurements obtained from both intercostal and subxiphoidal views were compared. Mean values for the average, median, and maximum two-dimensional shear wave velocities (2D SWV) for the closed EHPSS were 2.88 +/-0.11 m/s; 2.83 +/-0.11 m/s; and 3.75 +/-0.16 m/s, respectively. In the MAPSS dogs, mean values for the average, median, and maximum 2D SWV were 2.77 +/- 0.17 m/s; 2.71 +/- 0.17 m/s; and 3.66 +/-0.24 m/s, respectively. No significant differences in 2D SWV were present between dogs with closed EHPSS and those with MAPSS (P = 0.33; P = 0.33; P = 0.42, respectively). When assessing potential differences between intercostal and subxiphoidal 2D SWV measurements, no effect was observed for the average and median 2D SWV (P = 0.06; P = 0.07, respectively). Yet, a significant difference was identified for the maximum 2D SWV between intercostal 4.00 +/-0.20 m/s and subxiphoidal 3.41 +/-0.17 m/s measurements (P = 0.02). The relevance of this finding is uncertain as many other studies about liver elastography only report mean and not maximum values.

B-Mode and Contrast-Enhanced Ultrasonography Aspects of Benign and Malignant Superficial Neoplasms in Dogs: A Preliminary Study.

Contrast-enhanced ultrasonography (CEUS) is considered a promising technique for differentiation of benign and malignant tumors in humans. However, few studies have assessed superficial neoplasms in dogs by means of CEUS. The aim of this study was to identify ultrasonographic criteria evaluated by B-mode ultrasound (US) and CEUS that may be used to distinguish benign and malignant superficial neoplasms in dogs. A total of 63 superficial neoplasms from 59 dogs were evaluated using B-mode US and CEUS prior to histopathologic examination. Qualitative and quantitative parameters were compared between benign and malignant neoplasms by Fischer's exact test or fixed effects model. With B-mode US, a significant difference was found for border definition, echogenicity and echotexture. With CEUS, a significant difference was found for the enhancement pattern at wash-in and the wash-out area under the curve at the center of the neoplasm. Malignant neoplasms had on average a lower regional blood volume during the wash-out phase compared to benign neoplasms. Despite these significant differences, there was a considerable overlap in B-mode and CEUS parameters between benign and malignant neoplasms. In conclusion, B-mode US and CEUS might contribute to malignancy prediction; however, based on individual ultrasonographic parameters, they seem unable to replace cytology or histopathology.

Association of recessive c.430G>A (p.(Gly144Arg)) thyroid peroxidase variant with primary congenital hypothyroidism in cats.

BACKGROUND: Primary congenital hypothyroidism (CH) is a rare endocrine disorder in cats with a largely unknown genetic cause. OBJECTIVES: Describe the clinical presentation of CH in 11 affected cats and identify the causal genetic variant. ANIMALS: Eleven CH-cats from 10 unrelated families, 11 CH-free family members, 21 unrelated CH-free cats, and 155 unrelated nondiagnosed cats from different breeds. METHODS: Case control study of CH-cats and their siblings (2019-2021). Diagnosis was based on low to low-normal serum thyroxine (T4) concentrations, high thyroid-stimulating hormone (TSH) concentrations and clinical signs compatible with CH. We identified the causal variant using Sanger sequencing, genotyping via PCR-RFLP and variant interpretation using ACMG/AMP guidelines. RESULTS: All CH-cats (5 weeks-8 years) had disproportionate dwarfism. A goiter was not palpable in all. Thyroid scintigraphy with radiopertechnetate showed abnormally high uptake by thyroid glands, whereas scintigraphy with radioiodine showed abnormally low uptake, compatible with a defect in iodine organification by thyroid peroxidase (TPO). All cases were homozygous for TPO variant XM_006930524.4:c.430G>A(p.(Gly144Arg)), while none of the CH-free cats were. All sampled parents were heterozygous for this recessive variant. This variant was found in 15 cat breeds with an estimated allele frequency of 9%. CONCLUSIONS AND CLINICAL IMPORTANCE: Disproportionate dwarfism, abnormally high TSH and abnormally low to low-normal T4 concentrations are diagnostic for CH in cats. All cases had dyshormonogenesis demonstrated by thyroid scintigraphy. This novel TPO missense variant (not described in humans) causes CH in cats and awareness of it can assist in diagnosis and breeding.

Total lipid concentration of hairs increases after successful attenuation of extrahepatic portosystemic shunts in dogs.

BACKGROUND: Skin and coat quality can reflect nutritional deficiencies in humans and dogs with liver diseases. HYPOTHESIS/OBJECTIVES: Determine skin and coat quality based on a scoring protocol and skin biopsies in dogs with an extrahepatic portosystemic shunt (EHPSS), and determine total lipid concentrations in hairs of dogs at time of surgery and 3 months after successful shunt closure. ANIMALS: Ten client-owned dogs that underwent successful gradual attenuation of EHPSS, as defined by transsplenic portal scintigraphy, were included. MATERIALS AND METHODS: A prospective cohort study was performed. All dogs underwent gradual attenuation of the EHPSS. Skin and coat scoring was performed at diagnosis, surgery, and 1 and 3 months postoperatively. Hair was plucked from the lumbar region for total lipid analysis and an 8 mm punch skin biopsy was taken at time of surgery and 3 months postoperatively, when the dogs underwent transsplenic portal scintigraphy to determine EHPSS closure. RESULTS: No significant differences were observed in skin and coat scoring over time. Total lipid concentrations of hairs increased significantly from surgery to 3 months postoperatively [30 µg/mg hair (13-56 µg/mg hair) to 47 µg/mg hair (25-63 µg/mg hair); p = 0.005]. Skin biopsies showed the presence of significantly more scales 3 months postoperatively (p = 0.018). CONCLUSIONS AND CLINICAL RELEVANCE: A significant increase in total lipid concentrations in hairs suggests that successful surgical attenuation of EHPSS improves either intestinal absorption of lipids, fat metabolism in the liver, or a combination of both.

Contexte - La qualité de la peau et du pelage peut refléter des carences nutritionnelles chez les humains et les chiens atteints de maladies du foie. Hypothèse/Objectifs - Déterminer la qualité de la peau et du pelage sur la base d'un protocole de notation et de biopsies cutanées chez les chiens avec un shunt portosystémique extrahépatique (EHPSS), et déterminer les concentrations totales de lipides dans les poils des chiens au moment de la chirurgie et trois mois après la fermeture réussie du shunt. Animaux - Dix chiens appartenant à des clients qui ont subi une atténuation progressive réussie de l'EHPSS, telle que définie par la scintigraphie portale trans-splénique, ont été inclus. Matériels et méthodes - Une étude de cohorte prospective a été réalisée. Tous les chiens ont subi une atténuation progressive de l'EHPSS. Une notation de la peau et du pelage a été réalisée au moment du diagnostic, de la chirurgie et un et trois mois après l'opération. Les cheveux ont été prélevés dans la région lombaire pour une analyse des lipides totaux et une biopsie cutanée à l'emporte-pièce de 8 mm a été effectuée au moment de la chirurgie et trois mois après l'opération, lorsque les chiens ont subi une scintigraphie portale trans-splénique pour déterminer la fermeture de l'EHPSS. Résultats - Aucune différence significative n'a été observée dans la notation de la peau et du pelage au fil du temps. Les concentrations totales de lipides dans les poils ont augmenté de manière significative entre la chirurgie et trois mois après l'opération [30 µg/mg de poils (13-56 µg/mg de poils) à 47 µg/mg de poils (25-63 µg/mg de poils) ; P = 0,005]. Les biopsies cutanées ont montré la présence de significativement plus d'écailles trois mois après l'opération (P = 0,018). Conclusions et pertinence clinique - Une augmentation significative des concentrations totales de lipides dans les cheveux suggère qu'une atténuation chirurgicale réussie de l'EHPSS améliore soit l'absorption intestinale des lipides, soit le métabolisme des graisses dans le foie, soit une combinaison des deux.

Introducción- la calidad de la piel y el pelaje puede reflejar deficiencias nutricionales en humanos y perros con enfermedades hepáticas. Hipótesis/Objetivos- determinar la calidad de la piel y el pelaje según un protocolo de valoración y en biopsias de piel en perros con shunt portosistémico extrahepática (EHPSS) y determinar las concentraciones totales de lípidos en el pelo de los perros en el momento de la cirugía y tres meses después del tratamiento exitoso del shunt. Animales- se incluyeron diez perros de propietarios particulares que se sometieron a una atenuación gradual exitosa de EHPSS, según se identificó mediante por gammagrafía portal transesplénica. Materiales y métodos - Se realizó un estudio de cohorte prospectivo. A todos los perros se les realizó una atenuación gradual del EHPSS. La valoración de la piel y el pelaje se realizó en el momento del diagnóstico, la cirugía y uno y tres meses después de la operación. Se arrancó el pelo de la región lumbar para el análisis de lípidos totales y se tomó una biopsia de piel con sacabocados (punch) de 8 mm en el momento de la cirugía y tres meses después de la operación, cuando los perros se sometieron a una gammagrafía portal transesplénica para determinar el cierre de EHPSS. Resultados- no se observaron diferencias significativas en la valoración de la piel y el pelaje a lo largo del tiempo. Las concentraciones de lípidos totales del pelo aumentó significativamente desde la cirugía hasta los tres meses posteriores a la operación [30 µg/mg de pelo (13-56 µg/mg de pelo) a 47 µg/mg de cabello (25-63 µg/mg de pelo); P = 0,005]. Las biopsias de piel mostraron la presencia de mayor cantidad de escamas de forma significativa tres meses después de la operación (P = 0,018). Conclusiones y relevancia clínica- un aumento significativo en las concentraciones de lípidos totales en el pelo sugiere que la atenuación quirúrgica exitosa de EHPSS mejora la absorción intestinal de lípidos, el metabolismo de las grasas en el hígado o una combinación de ambos.

Contexto - A qualidade da pele e dos pelos pode refletir deficiências nutricionais em humanos e cães com hepatopatias. Hipótese/Objetivos - Determinar a qualidade da pele e pelos baseada em um protocolo de escore e biópsias cutâneas em cães com shunt portossistêmico extra-hepático (EHPSS) e determinar as concentrações lipídicas totais nos pelos de cães no momento da cirurgia e três meses após o fechamento bem-sucedido do shunt. Animais - Foram incluídos dez cães de proprietários submetidos à atenuação gradual do EHPSS bem-sucedida, confirmada por cintilografia portal transesplênica. Materiais e métodos - Realizou-se um estudo de coorte prospectivo. Todos os cães foram submetidos à atenuação gradual do EHPSS. A classificação de pele e pelos em escores foi realizada no diagnóstico, cirurgia, e com um e três meses de pós-operatório. Os pelos foram arrancados da região lombar para análise lipídica total e uma biópsia com punch de 8mm foi coletada no momento da cirurgia e com três meses de pós-operatório, quando os cães foram submetidos à cintilografia portal transesplênica para determinar o fechamento do EHPSS. Resultados - Não foram observadas diferenças significativas nos escores de pele e pelos ao longo do tempo. As concentrações de lipídicas totais aumentaram significativamente da cirurgia aos três meses de pós-operatório [30 µg/mg de pelo (13-56 µg/mg pelo) para 47 µg/mg de pelo (25-63 µg/mg de pelo); P = 0,005]. As biópsias cutâneas revelaram a presença de significativamente mais escamas com três meses de pós-operatório (P = 0,018). Conclusões e relevância clínica - O aumento significativo de concentrações lipídicas totais nos pelos sugere que a atenuação cirúrgica de EHPSS bem-sucedida melhora tanto a absorção intestinal de lipídeos quanto o metabolismo de gordura no fígado, ou uma combinação dos dois.

Age estimation in young dogs by radiographic assessment of the canine pulp cavity/tooth width ratio.

Age estimation in adult dogs can be performed by the radiographic measurement of the tooth pulp cavity, but the technique has hardly been described. In this study, the application of measuring pulp/tooth width ratios (P/T ratios) of the maxillary canine teeth was investigated. Pulp and tooth widths were measured at two locations on 166 maxillary canine teeth of the heads of 84 dog cadavers, using digital extraoral lateral oblique open mouth radiographs. The dogs belonged to different breeds and sexes and had a known age between 194 and 1907 days (approximately 6 months - 5 years). Both at the cemento-enamel junction (CE) and the half-height of the tooth, a comparable non-linear regression with age was demonstrated. Measuring at the CE location was less hindered by wear or superimposition. No statistically significant difference according to sex and breed size and no clinically significant difference according to skull type was found. The highest predictable capacity was found in the youngest dogs until the age of 448 days, of which 84.4% of the canine teeth had a P/T ratio above 0.39. Our results demonstrate that measuring P/T ratios of canine teeth can be used in practice to assign dogs to age categories, with the highest accuracy in young adult dogs.

Diagnostic value of liver function tests and ultrasonography in dogs with suspected congenital portosystemic shunts.

BACKGROUND: Diagnosing a congenital portosystemic shunt (cPSS) in dogs can be challenging. The current study aims to report diagnostic performance of fasting ammonia (FA), preprandial, postprandial and paired serum bile acids (SBA) and abdominal ultrasound (aUS) in dogs suspected of having a cPSS. METHODS: Medical records of dogs suspected of having a cPSS at initial presentation were retrospectively reviewed. RESULTS: In total, 192 dogs suspected of cPSS were included: a cPSS was confirmed in 147 dogs and excluded in 45 dogs. FA had the best combined sensitivity and specificity (77.4 and 93.3%, respectively) to diagnose cPSS. The sensitivity and negative predictive value were 100.0% for paired SBA, making paired SBA the best test to exclude cPSS in this population. Sensitivity and specificity of aUS were 80.8 and 90.0%, respectively. CONCLUSIONS: In dogs with clinical signs compatible with cPSS, elevated FA is suggestive of cPSS, whereas normal paired SBA makes the presence of a cPSS unlikely. Although aUS is a useful tool to diagnose cPSS, additional imaging is required to visualize cPSS in almost 20% of cases. Furthermore, the localisation of cPSS can be misdiagnosed, especially in case of extrahepatic cPSS that do not insert into the prehepatic vena cava.

Shear wave elastography of lymph nodes in dogs with head and neck cancer: A pilot study.

Shear wave elastography (SWE) is a novel ultrasound imaging technique, used in human medicine to differentiate metastatic from non-metastatic lymph nodes (LNs) based on higher tissue stiffness. The objective of this pilot study was to evaluate whether canine metastatic LNs were stiffer compared to non-metastatic LNs. SWE of sentinel or regional LNs in dogs with head and neck cancer was performed. Ten elastograms of each LN were acquired. In each elastogram, mean, median, and maximum shear wave velocities (SWVs) were calculated in the most elastic region, the stiffest region, and the entire LN. The means of those SWVs for each region of each LN were subsequently calculated. Furthermore, a stepwise subsampling was performed to assess the effect of the number of acquired elastograms on the consistency of the classification of a LN as metastatic or not. Twenty-four LNs in 15 dogs with head and neck cancer were included, of which 10 LNs were metastatic. Metastatic medial retropharyngeal and mandibular LNs were successfully distinguished from non-metastatic LNs based on higher mean and median SWVs in the stiffest region and higher maximum SWVs in entire LNs. Furthermore, maximum SWVs in the stiffest region of mandibular LNs were higher in metastatic LNs compared to non-metastatic LNs. Downstream analyses demonstrated that at least eight elastograms were necessary to perform reliable analyses. This pilot trial demonstrated that SWE has potential to discriminate metastatic from non-metastatic LNs; however, LN status should be based on at least eight elastograms in future clinical trials.

Persistent hypercobalaminemia three months after successful gradual attenuation of extrahepatic shunts in dogs: a prospective cohort study.

BACKGROUND: Deficiencies in vitamin A and D and disorders in the vitamin B complex are often present in people with chronic liver diseases. So far, the serum concentrations of these vitamins have not yet been studied in dogs with congenital extrahepatic portosystemic shunts (EHPSS), who also have some degree of liver dysfunction. The objective was to assess serum vitamin concentrations in dogs with EHPSS from diagnosis to complete closure. A prospective cohort study was performed using ten client-owned dogs with EHPSS, closed after gradual surgical attenuation. Serum concentrations of vitamin A, 25-hydroxyvitamin D, folic acid, cobalamin and methylmalonic acid (MMA) were measured at diagnosis prior to institution of medical therapy, prior to surgery, and three months after gradual attenuation and complete closure of the EHPSS. RESULTS: At diagnosis, median serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid were 18.2 µg/dL (8.8 - 79.5 µg/dL), 51.8 ng/mL (19.4 - 109.0 ng/mL), and 8.1 µg/L (5.2 - 14.5 µg/L), respectively, which increased significantly postoperatively (88.3 µg/dL (51.6 - 182.2 µg/dL, P=0.005), 89.6 ng/mL (49.3 - >150.0 ng/mL, P =0.005), and 14.8 µg/L (11.5 - 17.7 µg/L, P <0.001), respectively). Median serum cobalamin concentrations were 735.5 ng/L (470 - 1388 ng/L) at diagnosis and did not significantly decrease postoperatively (P =0.122). Both at diagnosis and three months postoperatively 7/10 dogs had hypercobalaminemia. CONCLUSIONS: Serum concentrations of vitamin A, 25-hydroxyvitamin D and folic acid significantly increase after surgical attenuation. Nevertheless, persistent hypercobalaminemia is suggestive of ongoing liver dysfunction, despite successful surgery.

The sesamoid bone in the long abductor muscle tendon of the first digit in the dog.

The sesamoid bone in the tendon of the m. abductor digiti primi longus is considered present in most dog breeds and is described to be radiologically detectable at the level of the carpus from the age of 4 months. However, an extensive investigation of this sesamoid bone has not been conducted before. The aim of this study was therefore to determine its prevalence in different dog breeds, to describe its histological development, and to determine the age at which it becomes radiologically visible. The prevalence of the sesamoid bone was assessed on radiographic images of the carpus or by dissection of the carpal region in 743 adult dogs of 115 breeds. Its development was studied by dissection and histological analysis in 45 puppies and its timing of radiological appearance was evaluated in 209 puppies. At least one sesamoid bone was present in all adult dogs, except for 14 dogs of six breeds of predominantly the small breed category. The lowest prevalence rate of 38.46% was exhibited in the French bulldog. The histological development could be divided into five stages. The first radiographic appearance corresponded to the coalescence of smaller ossification centers into one big nucleus (stage 4). The mean time of radiographic appearance was 108.4 days. This study provides extensive data on the prevalence and timing of the radiographic appearance of a sesamoid at the carpus of the dog. The data on radiographic appearance may be helpful in the age estimation of puppies.

Shear wave velocity measurements obtained in different regions are repeatable for presumed normal canine lymph nodes: A pilot study.

Shear wave elastography (SWE) has been applied as a noninvasive method for predicting regional lymph node (LN) metastases in human and veterinary patients. However, published studies describing standardized protocols and repeatability of this technique are currently lacking. The objective of this prospective, pilot, observer agreement study was to determine whether different shear wave velocity (SWV) measurements obtained in different regions of presumed normal canine LNs would be repeatable. Two imagers consecutively performed shear wave elastography of submandibular, superficial inguinal, and popliteal LNs in 10, clinically healthy adult dogs. Ten elastograms of each LN were acquired by each imager. In each adequate elastogram, three regions of interest (ROIs) were placed in the softest and stiffest region of the LN. Additionally, one ROI was drawn covering the entire LN. In each ROI, mean, median, and maximum SWVs were calculated. Mean values for the mean, median, and maximum SWVs varied from 2.33 to 3.10 m/s, 2.32 to 3.10 m/s, and 2.61 to 4.09 m/s, respectively. Intra- and interobserver agreements were acceptable. Superficial inguinal LNs demonstrated the highest intra- and interobserver agreement, followed by the popliteal and the submandibular LNs, respectively. Using the different measurements (mean, median, or maximum SWVs) had no significant effect on the intra- and interobserver variability, neither did the region (softest, stiffest, or entire LN). Findings indicated that all evaluated measurements and regions could be used to obtain reliable elastography data of presumed normal canine LNs. Clinical trials in dogs with cancer are necessary to compare SWVs of metastatic LNs with the reported SWVs and evaluate whether various measurements and regions can also be used in metastatic LNs.

Impact of adaptive gastric electrical stimulation on weight, food intake, and food intake rate in dogs.

BACKGROUND: Gastric electrical stimulation (GES) has been studied for decades as a promising treatment for obesity. Stimulation pulses with fixed amplitude and pulse width are usually applied, but these have limitations with regard to overcoming habituation to GES and inter-subject variation. This study aims to analyze the efficacy of an adaptive GES protocol for reducing food intake and maintaining lean weight in dogs. METHODS: Six beagle dogs were implanted with a remotely programmable gastric stimulator. An adaptive protocol was designed to increase the stimulation energy proportionally to the excess of food consumption, with respect to the dogs' maintenance energy requirements. After surgery and habituation to experimental conditions, the dogs went through both a control and a stimulation period of 4 weeks each, in a randomized order. The stimulation parameters were adapted daily. Body weight, food intake, food intake rate, and postprandial cutaneous electrogastrograms (EGG) were recorded to assess the effect of adaptive GES. RESULTS: Adaptive GES decreased food intake and food intake rate (p < 0.05) resulting in weight maintenance. In the absence of GES, the dogs gained weight (p < 0.05). Postprandial EGG dominant frequency was accelerated by GES (p < 0.05). The strategy of adapting the stimulation energy was effective in causing significant mid-term changes. CONCLUSION: Adaptive GES is effective for reducing food intake and maintaining lean weight. The proposed adaptive strategy may offer benefits to counter habituation and adapt to inter-subject variation in clinical use of GES for obesity.