BackgroundMany patients with a congenital extrahepatic portosystemic shunt (PSS) do not tolerate an immediate shunt closure. Therefore, slow progressive techniques were developed. To evaluate the success of shunt closure diagnostic imaging is essential to identify possible residual blood flow through the shunt vessel. There is a lack of information about the reliability of computed tomography angiography (CTA) for evaluating residual flow through a PSS after treatment. The purpose of this prospective study was to compare the results of CTA with splenoportography. Three months after cellophane banding CTA and splenoportography were performed in 20 dogs and reviewed by three independent examiners, respectively. In both imaging modalities the presences of a residual shunt was judged as present or absent and the extent of visibility of portal vasculature was recorded.ResultsBased on the evaluation of the splenoportography residual flow through shunt was present in 6 dogs. The classification of residual shunt present or absent showed a substantial to perfect agreement (κ = 0.65–1.00) between the observers in splenoportography and a slight to moderate agreement (κ = 0.11–0.51) for CTA. Sensitivity and specificity varied between 0.50 and 1.00 and 0.57–0.85, respectively. Significant correlation between CTA and splenoportography for the classification of residual shunt was present only in one observer but not in the other two.ConclusionMore studies were classified as residual shunt positive with CTA compared to splenoportography. It remains unclear which methods do reflect reality better and thus which method is superior. The greater inter-rater agreement for splenoportography suggests a greater reliability of this technique.

Background Congenital anomalies of the aortic arch are important as they may be associated with vascular ring anomalies. The most common vascular ring anomaly in dogs is a persistent right aortic arch. However, published data of the distribution of the different types of vascular ring anomalies and other aortic arch anomalies are lacking. The objective of this retrospective descriptive study was to evaluate both the prevalence and the different types of aortic arch anomalies that can be detected using thoracic computed tomography (CT) examination. Archived thoracic CT examinations acquired between 2008 and 2020 at a single institution were retrospectively evaluated by 2 evaluators for the prevalence and type of aortic arch anomaly. Breed, age, and presenting complaint were obtained from the medical record system. Results A total of 213 CT studies were evaluated; 21 dogs (21/213, 9.9%) showed a right aortic arch and a left ligamentum arteriosum with compression of the esophagus. The following incidental additional findings were detected: aberrant left subclavian artery (17/21, 76.2%), branching from the persistent ductus arteriosus (PDA) (1/21, 4.8%), left-sided brachiocephalic trunk (3/21, 14.3%), bicarotid trunk (17/21, 81.0%), double aortic arch (1/21, 4.8%). One hundred ninety two dogs (192/213, 90.1%) showed a left aortic arch without esophageal compression. The following additional abnormalities were obtained in those dogs with left aortic arch: aberrant right subclavian artery (3/192, 1.6%) without clinical signs of esophageal compression, aberrant vessel branching from the aorta into the left caudal lung lobe (2/192, 1.0%), focal dilatation of the left or right subclavian artery (2/192, 1.0%), bicarotid trunk (1/192, 0.5%). Conclusion Similar to previous studies an aberrant left subclavian artery is the most common additional finding in dogs with persistent right aortic arch. Newly, a left-sided brachiocephalic trunk was identified in 14.3% of the dogs with a persistent right aortic arch; no additional compression was caused by the left sided brachiocephalic trunk. Similarly, aberrant right subclavian artery can be an incidental CT finding without causing compression of the esophagus.

Zusammenfassung Gegenstand und Ziel Ziel dieser prospektiven Pilotstudie war zu beurteilen, ob die physiologische Glandula parathyroidea beim Hund computertomografisch dargestellt werden kann, und eine Beschreibung ihres CT-Erscheinungsbildes zu geben. Material und Methoden In die Studie wurden 25 Hunde aufgenommen, bei denen aufgrund von Erkrankungen im Halsbereich ohne Bezug zu Schild- oder Nebenschilddrüse ein CT-Scan erfolgte. Einschlusskriterium waren unauffällige Befunde bei der allgemeinen klinischen Untersuchung und der Blutuntersuchung (Blutbild und blutchemische Analyse). CT-Bilder vor und nach Kontrastmittelapplikation (30–45 Sekunden nach der Kontrastmittelinjektion, frühe venöse Phase) wurden mit einem 16-Schichten-Spiral-CT unter Verwendung eines Field of View von 18 cm, einer Schichtdicke von 1 mm und einer Matrix von 512 × 512 angefertigt. Zwei Radiologen begutachteten die CT-Aufnahmen unabhängig voneinander. Die Sichtbarkeit der Parathyreoidea wurde erfasst und die Interobserver-Reliabilität ermittelt. Bei den darstellbaren Nebenschilddrüsen wurden folgende Parameter bestimmt: Größe, Dichte (in Hounsfield Units [HU], vor und nach Kontrastmittelgabe), Dichte der Schilddrüse, Abgrenzung (exzellent, mäßig, schlecht). Ergebnisse Nur 20 bzw. 25 Nebenschilddrüsen waren durch die beiden Untersucher erkennbar. Die Anzahl differierte zwischen Nativaufnahmen und Bildern nach Kontrastmittelgabe nicht. Die Interobserver-Reliabilität hinsichtlich der Erkennbarkeit war moderat (κ = 0,40). Für Länge, Breite und Höhe der Nebenschilddrüsen (Mittelwert ± Standardabweichung) ergaben sich 4,2 × 2,5 × 2,9 mm ± 1,3 × 0,8 × 1,0 mm. Die Dichte betrug 39,7 ± 20,6 HU vor und 103,1 ± 47,1 HU nach Kontrastmittelgabe. Damit stellten sich die Nebenschilddrüsen im Vergleich zur Schilddrüse (vor und nach Kontrastmittelgabe 166,7 ± 34,3 HU bzw. 234,0 ± 60,1 HU) hypoattenuierend dar. Schlussfolgerung Diese Studie liefert die erste Beschreibung des CT-Erscheinungsbilds der angenommen physiologischen Nebenschilddrüse beim Hund. Die Sichtbarkeit des Organs war jedoch schlecht. Klinische Relevanz Trotz der schlechten Visualisierung der Nebenschilddrüse im CT ist sie gelegentlich wahrnehmbar. Die ermittelten Dimensionen waren teilweise größer als bisher für sonografische Darstellung beschrieben, ohne dass die untersuchten Hunde erkennbare Symptome eines Hyperparathyreodismus aufwiesen. Eine computertomografisch sichtbare Nebenschilddrüse impliziert daher möglicherweise nicht unbedingt eine Erkrankung. Weitere Studien dazu sind notwendig.

Background: Seizures are considered a clinical sign in dogs with internal hydrocephalus but are not found in recent studies. Seizure prevalence due to ventricular enlargement and the prevalence of postoperative seizures in animals is not known. Objectives: To determine seizure prevalence in dogs and cats with idiopathic internal hydrocephalus, to identify risk factors for seizure development, and to determine seizure prevalence in a 2-year period after ventriculo-peritoneal shunting (VPS). Animals: Records and MRIs of 197 animals from 2001 to December 2019 were investigated. A total of 121 animals (98 dogs and 23 cats) were included in the study. Methods: A retrospective multicenter case cohort study was conducted. Databases were searched for dogs and cats with internal hydrocephalus. MRI and CSF examinations were evaluated for signs of additional underlying disorders. Prevalence of seizures was estimated for animals showing only hydrocephalus internus. Risk factors were evaluated according to age, morphometric and morphological findings in the brain. All animals that underwent surgery were reexamined 2 years after surgery. Results: One hundred twenty-one animals (98 dogs and 23 cats) with internal hydrocephalus met the inclusion criteria. Seizure prevalence in dogs and cats with internal hydrocephalus was low (1.7%; <5.8% CI 95%). Seizures were not observed in the 2-year period after surgery. Conclusion and Clinical Importance: Seizure prevalence in dogs and cats diagnosed with hydrocephalus internus is low. Seizures in association with VPS do not seem to be a complication of the procedure.

A 15-year old, neutered female, domestic shorthaired cat was presented for evaluation of a 3-month history of paroxysmal falling over and trembling. In laboratory work the cat displayed a mild hypoglycemia. Ultrasound revealed a nodule in the left pancreatic lobe and surgical excision was performed. The histological diagnosis was an insulinoma. To the authors knowledge this is the first ultrasound description of an insulinoma in a cat. Up to date the cat has a survival time of 32 months without recurrence of symptoms.