Ultrasonographic appearance of retained surgical sponges and gauzes in the acute postoperative period: a phantom and cadaveric study.

Retained surgical sponges or gauzes (RSS) are an uncommon complication of exploratory laparotomy surgery and pose a clinically significant risk to the patient. The purpose of this two-part, prospective, descriptive study was to describe the previously uncharacterized ultrasonographic appearance of RSS in phantom and cadaveric models of the acute postoperative period (24-48 h). For the first part of the study, a gelatin phantom containing a woven gauze with a radiopaque marker (radiopaque gauze), a woven gauze with no marker (nonradiopaque gauze), and a laparotomy sponge with a radiopaque marker (radiopaque sponge) was evaluated with ultrasonography. For the second part of the study, a total of 23 gauzes and sponges (of the aforementioned three types) were placed within the peritoneal cavity of 20 cadavers in one of three randomized locations during an exploratory laparotomy laboratory. The cadavers were imaged with ultrasonography 17 h later and still images and video clips were reviewed. The retained surgical sponges and gauzes in the gelatin phantom displayed multiple hyperechoic layers and variable degrees of distal acoustic shadowing. In cadavers, 100% (23/23) of the retained surgical sponges and gauzes displayed a single hyperechoic layer of variable thickness and distal acoustic shadowing. In 95.6% (22/23) retained sponges and gauzes, there was a thin hypoechoic layer noted superficially to the hyperechoic layer. An improved understanding of the ultrasonographic appearance of retained sponges or gauzes in the acute postoperative period may assist in the identification of these objects.

Computed tomographic appearance of sialoceles in 12 dogs.

Published findings on the computed tomographic (CT) appearance of sialoceles are limited to brief descriptions from reported cases in eight dogs and one cat. The authors have seen sialoceles with CT characteristics that are not consistent with these previous reports. The purpose of this multicenter, retrospective, descriptive, case series study was to provide more detailed descriptions of the CT appearance of confirmed sialoceles in dogs. Dogs over a 10-year period with cytologically or histologically confirmed sialoceles and pre- and postcontrast CT studies of the head were included. Multiple qualitative and quantitative features were described for each sialocele with histological correlation. Twelve dogs with a total of 13 sialoceles were identified, including: seven cervical sialoceles, three complex (combined cervical and sublingual) sialoceles, two sublingual sialoceles, and one zygomatic sialocele. All sialoceles were characterized by fluid attenuating, non-contrast enhancing contents (median 18.5 HU) and soft tissue attenuating, contrast-enhancing walls. The external margins of all sialocele walls were smooth; however, the internal margins in six sialoceles were irregular with poorly defined nodular to frond-like protrusions. Mineralized foci of variable size (range < 1 mm to 4.8 mm) and attenuation (range 119 to 1253 HU) were present in seven sialoceles and histologically identified as sialoliths (three sialoceles) and osseous metaplasia (two sialoceles). A unique finding in the sialoceles in this study was the presence of intraluminal nodular to frond-like protrusions arising from the wall. This study also reports the CT appearance of cervical and complex sialoceles and sialocele mineralizations.

Radiographic and CT features of colonic entrapment due to an omental rent in a dog.

A 2-year-old female spayed Great Dane presented for inappetence and lethargy. Abdominal radiographs revealed a severely gas-distended segment of colon. Computed tomography was performed and characterized a 180° anticlockwise colonic torsion with entrapment in a mesenteric/omental rent without vascular compromise. Exploratory laparotomy confirmed entrapment, but not colonic torsion. Computed tomography provided important information to assist clinical management decisions for this dog with colonic entrapment.

Anal sacculiths may be an incidental finding in dogs.

Mineral-attenuating material is occasionally seen in the anal sacs of dogs during abdominal CT studies. This retrospective, descriptive study was performed to estimate the prevalence and CT appearance of this mineral-attenuating material. A total of 357 abdominal CTs were reviewed retrospectively. The mineral-attenuating material was most easily identifiable using the brain window setting (window width: 120 HU; window level: 40 HU). In the current study, the prevalence of mineral-attenuating material in the anal sacs was 7.6% (95% confidence interval, 5.0-10.8%) with 48.1% bilateral involvement and equal distribution in the right and left in dogs with unilateral involvement. Successful collection and material analysis were performed in three dogs. The material was determined to be 100% dried blood, 100% waxy matter, and a "small amount of fat enmeshed in unidentified noncrystallined material." Given the CT appearance and the Hounsfield unit of these mineral-attenuating material within the anal sacs, the term "anal sacculiths" is proposed. All dogs with anal sacculiths within this study population did not have any reported disease of the anal sacs.

Presumed acquired dynamic pectus excavatum in a cat.

An 11-year-old, spayed female American domestic shorthair cat was presented with open-mouth breathing and dyspnea due to respiratory tract disease. Radiographically, there was thickening of the retropharyngeal soft tissue and soft palate, focal pulmonary change, and severe pectus excavatum (PE), best seen on the left lateral view. Repeat thoracic radiographs 4 months later showed persistent PE, but only on the right lateral view; PE was absent on the left lateral view. The dynamic component of the observed PE was presumably acquired secondary to chronic upper respiratory disease and/or concurrent increased pliability of the thoracic wall from prolonged prednisolone treatment.

Pectus excavatum dynamique acquis présumé chez un chat. Une chatte domestique américaine stérilisée de 11 ans a présenté une respiration à bouche ouverte et une dyspnée due à une maladie des voies respiratoires. Radiographiquement, il y avait un épaississement des tissus mous rétropharyngés et du palais mou, une modification pulmonaire focale et un pectus excavatum (PE) sévère, mieux visible sur la vue latérale gauche. Des radiographies thoraciques répétées 4 mois plus tard ont montré une PE persistante, mais uniquement sur la vue latérale droite; la PE était absent sur la vue latérale gauche. La composante dynamique de la PE observée était vraisemblablement acquise secondaire à une maladie chronique des voies respiratoires supérieures et/ou à une flexibilité accrue concomitante de la paroi thoracique à la suite d'un traitement prolongé à la prednisolone.(Traduit par Dr Serge Messier).

Disseminated Rhodococcus equi in an Anglo-Nubian goat.

Disseminated Rhodococcus equi infection was diagnosed in an Anglo-Nubian goat presenting for non-weight bearing lameness of the right pelvic limb. Radiographs showed a moth-eaten osteolytic lesion in the proximal tibia suggestive of an aggressive bone lesion. Two pulmonary nodules were also present on thoracic radiographs. Initial antemortem cytology of the tibial lesion was suggestive of Rhodococcosis and the goat was sent to necropsy. Necropsy and bacterial culture confirmed the diagnosis of disseminated R. equi infection in the right tibia, lungs, and liver.

Ultrasonographic and computed tomographic features of rice bodies in an Arabian horse with atlantal bursitis.

A 19-year-old castrated Arabian male horse presented for evaluation of a firm mass at the dorsal cervical region. Ultrasonography and computed tomography revealed multiple well defined fusiform structures within the atlantal bursa. Multiple glossy smooth, white to yellowish, flattened fusiform structures were removed surgically. These structures were composed of dense fibrin with some leukocytes and red blood cells. The imaging and histopathological features of these structures were similar to chronic 'rice bodies' reported in humans with bursitis or tenosynovitis. This is the first veterinary report describing the imaging features of 'rice bodies' in a horse with atlantal bursitis.

Ultrasonographic features of colonic B-cell lymphoma with mesenteric lymphomatosis in a cat.

A 10-year-old male neutered Domestic Shorthair cat was referred for chronic inappetence, weight loss, and hematochezia and an abdominal mass. Abdominal ultrasonography revealed a heterogeneously hypoechoic transmural colonic mass, which extended beyond the serosa and into the adjacent mesentery. Cytology and clonality assays of fine needle aspirates of the mass and mesenteric nodules yielded a diagnosis of B-cell lymphoma. Colonic lymphoma with mesenteric involvement can have a similar appearance to carcinomatosis, therefore a definitive diagnosis requires sampling and further testing of the mesenteric lesions.

Computed tomographic features of confirmed gallbladder pathology in 34 dogs.

Gallbladder pathology is common in dogs, but published studies describing the computed tomographic (CT) appearance of many gallbladder pathologies are currently lacking. This retrospective, multicenter, cases series, descriptive study evaluated the CT features of confirmed gallbladder pathology in 34 dogs. In this subset of dogs, the most common pathologies included cystic mucosal hyperplasia (15/34, 44.1%), gallbladder wall edema (9/34, 26.5%), gallbladder mucocele (8/34, 23.5%), bactibilia (7/34, 20.6%), cholecystitis (6/34, 17.6%), white bile (6/34, 17.6%), and cholelithiasis (4/34, 11.8%). The presence of intraluminal nodules, gallbladder wall thickening, hyperattenuating material (35-100 HU), and mineral attenuating material (>100 HU) were the most common abnormalities detected. However, overlap of each of these findings with a variety of gallbladder pathologies showed that none of the findings were pathognomonic for any of these pathologies. The presence of any of these CT abnormalities should increase the suspicion of gallbladder pathology and prompt further evaluation of the gallbladder for definitive diagnosis.

Concurrent bullous emphysema, bronchointerstitial pneumonia with necrosis, and tension pneumothorax in an 8-week-old puppy.

An 8-week-old, male, mixed breed puppy was presented because of progressive respiratory distress. Thoracic radiographs revealed innumerable coalescing pulmonary bullae throughout the lungs with increased soft tissue opacity of the remaining pulmonary parenchyma and tension pneumothorax. Necropsy and histopathological findings were compatible with bullous emphysema and marked neutrophilic to histiocytic bronchointerstitial pneumonia with necrosis, bronchiectasis, fibrosis, dystrophic mineralization, and vasculitis with thrombosis. Tests for agents of infectious disease did not reveal an underlying etiological agent. This case highlights the radiographic, gross necropsy, and histopathologic features of a puppy with bullous emphysema and severe bronchointerstitial pneumonia with necrosis.

Un chiot mâle croisé âgé de 8 semaines fut présenté à cause de détresse respiratoire progressive. Des radiographies thoraciques ont révélé un nombre incalculable de bulles pulmonaires coalescentes à travers les poumons avec augmentation de l'opacité des tissus mous du parenchyme pulmonaire restant et un pneumothorax de tension. La nécropsie et les trouvailles histopathologiques étaient compatibles avec de l'emphysème bulleux et une pneumonie broncho-interstitielle neutrophilique et histiocytaire marquée avec nécrose, de la bronchiectasie, de la fibrose, une minéralisation dystrophique et une vasculite avec thrombose. Des tests pour agents infectieux de maladie n'ont pas permis de mettre en évidence un agent étiologique sous-jacent. Ce cas met en évidence les trouvailles radiographiques, de nécropsie et histopathologiques chez un chiot avec emphysème bulleux et pneumonie broncho-interstitielle avec nécrose.(Traduit par Dr Serge Messier).

Predominance of hypoechoic tissue changes in nine dogs with malignant prostatic lymphoma.

Neoplasia of the prostate is relatively uncommon in dogs with adenocarcinoma being the most common type. Non-epithelial tumors are rare and only individual cases of malignant lymphoma affecting the prostate have been reported. The purpose of this multi-institutional, retrospective, descriptive study was to characterize the ultrasonographic features of canine prostatic lymphoma. Inclusion criteria were an abdominal ultrasound and cytological/histological diagnosis of malignant prostatic lymphoma. Ultrasonographic features were recorded based on the original ultrasonographic reports and consensus opinion of two readers on the available image sets retrospectively. Nine dogs met the inclusion criteria with a mean age of 6.5 years. Seven dogs were intact and two neutered. Subjective prostatomegaly was noted in all patients however not reproducible by objective measurements. Altered shape with rounded/irregular margins was detected in 78% of the cases. All prostates presented either diffuse (three dogs) or focal/periurethral (four dogs) and/or multifocal areas of hypoechogenicity (three dogs). In one dog, focal and multifocal hypoechoic changes co-occurred. Prostatic mineralization was not present in any of the cases. Ultrasonographic features of infiltrative disease of multiple organs and/or lymphadenopathy was found in all cases. Even though malignant lymphoma is rare in the prostate, it should be included in the list of differentials in patients with hypoechoic lesions/areas, altered shape, lack of mineralization of the prostatic parenchyma and evidence of multiorgan involvement.

Survey of the prevalence and methodology of quality assurance for B-mode ultrasound image quality among veterinary sonographers.

Image quality in B-mode ultrasound is important as it reflects the diagnostic accuracy and diagnostic information provided during clinical scanning. Quality assurance programs for B-mode ultrasound systems/components are comprised of initial quality acceptance testing and subsequent regularly scheduled quality control testing. The importance of quality assurance programs for B-mode ultrasound image quality using ultrasound phantoms is well documented in the human medical and medical physics literature. The purpose of this prospective, cross-sectional, survey study was to determine the prevalence and methodology of quality acceptance testing and quality control testing of image quality for ultrasound system/components among veterinary sonographers. An online electronic survey was sent to 1497 members of veterinary imaging organizations: the American College of Veterinary Radiology, the Veterinary Ultrasound Society, and the European Association of Veterinary Diagnostic Imaging, and a total of 167 responses were received. The results showed that the percentages of veterinary sonographers performing quality acceptance testing and quality control testing are 42% (64/151; 95% confidence interval 34-52%) and 26% (40/156: 95% confidence interval 19-33%) respectively. Of the respondents who claimed to have quality acceptance testing or quality control testing of image quality in place for their ultrasound system/components, 0% have performed quality acceptance testing or quality control testing correctly (quality acceptance testing 95% confidence interval: 0-6%, quality control testing 95% confidence interval: 0-11%). Further education and guidelines are recommended for veterinary sonographers in the area of quality acceptance testing and quality control testing for B-mode ultrasound equipment/components.

Interobserver reliability of computed tomographic contouring of canine tonsils in radiation therapy treatment planning.

In radiation therapy (RT) treatment planning for canine head and neck cancer, the tonsils may be included as part of the treated volume. Delineation of tonsils on computed tomography (CT) scans is difficult. Error or uncertainty in the volume and location of contoured structures may result in treatment failure. The purpose of this prospective, observer agreement study was to assess the interobserver agreement of tonsillar contouring by two groups of trained observers. Thirty dogs undergoing pre- and post-contrast CT studies of the head were included. After the pre- and postcontrast CT scans, the tonsils were identified via direct visualization, barium paste was applied bilaterally to the visible tonsils, and a third CT scan was acquired. Data from each of the three CT scans were registered in an RT treatment planning system. Two groups of observers (one veterinary radiologist and one veterinary radiation oncologist in each group) contoured bilateral tonsils by consensus, obtaining three sets of contours. Tonsil volume and location data were obtained from both groups. The contour volumes and locations were compared between groups using mixed (fixed and random effect) linear models. There was no significant difference between each group's contours in terms of three-dimensional coordinates. However there was a significant difference between each group's contours in terms of the tonsillar volume (P < 0.0001). Pre- and postcontrast CT can be used to identify the location of canine tonsils with reasonable agreement between trained observers. Discrepancy in tonsillar volume between groups of trained observers may affect RT treatment outcome.

Ultrasound measurements of the caudal vena cava before and after blood donation in 9 greyhound dogs.

This prospective study evaluated variation in the diameter of the caudal vena cava (DCdVC) as a marker of change in intravascular volume before and after blood donation in greyhound dogs. A preliminary study determined that the DCdVC increased with body weight. Nine greyhound blood donors had ultrasonographic images acquired of the maximum and minimum DCdVCs in transverse and sagittal orientations and sagittal aortic diameter (AoD) before and after blood donation. The collapsibility index = [(maximal mean transverse DCdVC - minimal mean transverse DCdVC)/maximal mean transverse DCdVC] and transverse DCdVC:AoD ratio were calculated for each dog. In the greyhounds, the changes in mean minimal and maximal transverse DCdVC (0.69 and 0.84 mm, respectively) and sagittal mean maximal DCdVC (0.9 mm) and collapsibility index (0.018) were significantly different (P < 0.05) before and after blood donation. While statistically significant, the magnitude of DCdVC change found in this limited number of greyhound dogs with 8% intravascular volume loss during blood donation was small. This magnitude of change is likely indistinguishable in clinical patients.

Mesures par ultrason de la veine cave caudale avant et après le don de sang chez 9 chiens Greyhound. Cette étude prospective a évalué la variation du diamètre de la veine cave caudale (DCdVC) comme marqueur du changement du volume intravasculaire avant et après le don de sang chez les chiens Greyhound. Une étude préliminaire a déterminé que le DCdVC a augmenté le poids corporel. Neuf Greyhound donneurs de sang avaient des images échographiques acquises pour les DCdVC maximum et minimum dans les orientations transversales et sagittales et le diamètre aortique sagittal (AoD) avant et après le don de sang. L'indice de collapsibilité = [(DCdVC maximal transversal moyen ­ DCdVC minimal transversal moyen)/DCdVC maximal transversal moyen] et le ratio transversal DCdVC:AoD ont été calculés pour chaque chien. Chez les Greyhounds, les changements des DCdVC minimaux et maximaux transversaux moyens (0,69 et 0,84 mm, respectivement) et le DCdVC maximal sagittal moyen (0,9 mm) et l'indice de collapsibilité (0,018) étaient significativement différents (P < 0,05) avant et après le don de sang. Même si ce changement est significatif sur le plan statistique, l'ampleur du changement DCdVC constatée dans ce nombre limité de chiens Greyhound ayant 8 % de perte de volume intravasculaire durant le don de sang était faible. Cette ampleur de changement est probablement impossible à distinguer chez les patients cliniques.(Traduit par Isabelle Vallières).

Inguinal herniation of a mineralized paraprostatic cyst in a dog.

A firm mass was noted in the right inguinal subcutaneous region of an 11-year-old intact male Labrador retriever dog presented for right pelvic limb weakness. Pelvic radiographs showed 2 large ovoid structures with circumferential thin eggshell-like mineralization in the right external inguinal region. The structures were confirmed sonographically, and on magnetic resonance imaging as a large folded herniated mineralized paraprostatic cyst through a defect in the right inguinal wall. To the author's knowledge, this is the first published report of an inguinal herniated mineralized paraprostatic cyst.

Herniation inguinale d'un kyste paraprostatique minéralisé chez un chien. Une masse ferme a été observée dans la région sous-cutanée chez un Labrador retriever mâle intact âgé de 11 ans qui était présenté pour une faiblesse du membre pelvien droit et des radiographies pelviennes ont montré deux grosses structures ovoïdes avec une mince minéralisation circonférencielle semblable à une coquille d'oeuf dans la région inguinale droite. Les structures ont été confirmées par échographie et à l'imagerie par résonance magnétique comme un gros kyste paraprostatique replié minéralisé et hernié via un défaut de la paroi inguinale droite. À la connaissance de l'auteur, il s'agit du premier rapport publié d'un kyste paraprostatique minéralisé hernié inguinal.(Traduit par Isabelle Vallières).

IMAGING DIAGNOSIS-NUCLEAR SCINTIGRAPHIC, RADIOLOGICAL, AND PATHOLOGIC CHARACTERISTICS OF METASTATIC PILOMATRICOMA IN A DOG.

A 6-year-old castrated Goldendoodle dog was presented for left-sided lameness of 3 weeks' duration. Focal, moderate to marked increased 99m Tc-methylene diphosphonate (99m Tc-MDP) uptake was detected in the right caudal lung lobe, caudal angle of the left scapula, and the distal aspect of the left femur with whole body bone phase scintigraphy. Radiographs identified a well-circumscribed, oval-shaped soft tissue opaque mass in the right caudal lung lobe; a suspect oval-shaped osteolytic lesion in the proximal third of the left scapula; and an osteolytic lesion in the distal aspect of the left femur. Metastatic pilomatricoma was confirmed histologically at all three sites.

PREVALENCE AND SIGNIFICANCE OF AN ULTRASONOGRAPHIC COLONIC MUSCULARIS HYPERECHOIC BAND PARALLELING THE SEROSAL LAYER IN DOGS.

The muscularis layer of the canine colon has been reported to appear homogeneously hypoechoic on ultrasonography. A hyperechoic band in the muscularis layer paralleling the serosal surface has been observed by authors in routine canine abdominal ultrasound examinations. The purpose of this prospective and retrospective cross-sectional study was to determine the prevalence of this lesion, characterize its ultrasonographic and postmortem histologic features, and correlate its presence with clinical signs of gastrointestinal disease. In the prospective study, all dogs that underwent routine abdominal ultrasonography by one of two observers during a 4-week period were included without any exclusion criteria. One observer reviewed ultrasound images and recorded the presence or absence of this lesion and its distribution, e.g. focal (< 2 cm long) or diffuse (> 2 cm long). In the retrospective study, all dogs that had both abdominal ultrasonography and necropsy from January 2011 to December 2013 were included without any exclusion criteria. Histologic examinations were performed by two observers and Masson's trichrome stain was used to identify fibrous collagen. Prevalence for the hyperechoic band was 32% in the prospective and 4.8% in the retrospective sample populations, respectively. The hyperechoic band appeared as diffuse, focal, or a combination of both. Histologic sections were available for six dogs. In a few cases, the lesion corresponded to the presence of fibrous tissue in the myenteric plexus or in the tunica muscularis. None of the dogs had a history of diarrhea. Findings supported the hypothesis that a colonic muscularis hyperechoic band paralleling the serosal layer in dogs could be a normal variant rather than a marker of disease.

Ultrasonographic features of uterus masculinus in six dogs.

Uterus masculinus (persistent Mullerian duct) is a vestigial embryological remnant of the paramesonephric duct system in males and has been associated with clinical signs such as dysuria, incontinence, tenesmus and urethral obstruction in dogs. The radiological appearance of cystic uterus masculinus in dogs has been described previously with the aid of retrograde positive or negative contrast cystography. The purpose of this retrospective study was to describe ultrasonographic features of confirmed or presumed uterus masculinus in a group of dogs with confirmed or presumed disease. Ultrasonographic findings were recorded based on a consensus opinion of two readers. A uterus masculinus was defined as cylindrical when no lumen was observed and tubular when it had lumen that was filled with anechoic fluid. Six dogs met the inclusion criterion with a mean age of 8 years and 9 months. Uterus masculinus appeared as single (four dogs) or two (two dogs) horn-like, tubular (four dogs) or cylindrical (two dogs) structures, originating from the craniodorsal aspect of the prostate gland and extending cranially. The walls of the uterus masculinus were isoechoic to the urinary bladder wall. The diameter of the observed uterus masculinus varied from 0.3 cm to 1 cm. The length of the uterus masculinus varied from 2 cm to 6.5 cm but the cranial terminal end was not identified in two dogs. Concomitant prostatomegaly was seen in five dogs (83.3%) and urinary tract infection was noted in three dogs (50%). Findings indicated that uterus masculinus should be included as a differential diagnosis for male dogs with these ultrasonographic characteristics.

Differentiation of Antemortem and Postmortem Appendicular Fractures Using Magnetic Resonance Imaging Signal Intensity Changes in Bone and Soft Tissues.

Intraosseous T1-weighted (T1W) and short-tau inversion recovery (STIR) magnetic resonance imaging (MRI) signal intensity changes-so-called bone marrow edema-may be able to differentiate antemortem and postmortem fractures in human forensic imaging. The primary objective of this study was to investigate this hypothesis using an animal model. Three juvenile Landrace pigs were anesthetized and underwent MRI of both tibiae and both radii using a 1.5 T magnet. T1W, T2-weighted (T2W), STIR, and T2* sequences were included. Antemortem fractures were induced in both tibiae and postmortem fractures in both radii, and MRI was repeated. Two board-certified radiologists blinded to fracture group jointly evaluated the images for intraosseous and soft tissue signal intensity changes. Sensitivity (Se) and specificity (Sp) in identifying antemortem fractures were calculated based on intraosseous, soft tissue, and combined intraosseous and soft tissue signal intensity changes. Intraosseous and soft tissue signal intensity changes, when present, were hyperintense in all sequences. Intraosseous hyperintensity in T1W and T2W sequences yielded Sp of 100% for antemortem fractures. Regardless of sequence, soft tissue hyperintensity was comparatively more sensitive than intraosseous hyperintensity. Sensitivity for each sequence could be maximized by assessment of soft tissue and intraosseous hyperintense signals together; for the T1W sequence, such assessment optimized diagnostic utility yielding a Se of 100% and Sp of 83%. In summary, MRI-particularly the T1W sequence-can differentiate antemortem and postmortem fractures and may be a useful adjunct to the forensic analyses of fractures.