RESUMO
BACKGROUND: Hypoxia is a detrimental factor in solid tumors, leading to aggressiveness and therapy resistance. OMX, a tunable oxygen carrier from the heme nitric oxide/oxygen-binding (H-NOX) protein family, has the potential to reduce tumor hypoxia. [18F]Fluoromisonidazole ([18F]FMISO) positron emission tomography (PET) is the most widely used and investigated method for non-invasive imaging of tumor hypoxia. In this study, we used [18F]FMISO PET/CT (computed tomography) to assess the effect of OMX on tumor hypoxia in spontaneous canine tumors. RESULTS: Thirteen canine patients with various tumors (n = 14) were randomly divided into blocks of two, with the treatment groups alternating between receiving intratumoral (IT) OMX injection (OMX IT group) and intravenous (IV) OMX injection (OMX IV group). Tumors were regarded as hypoxic if maximum tumor-to-muscle ratio (TMRmax) was greater than 1.4. In addition, hypoxic volume (HV) was defined as the region with tumor-to-muscle ratio greater than 1.4 on [18F]FMISO PET images. Hypoxia was detected in 6/7 tumors in the OMX IT group and 5/7 tumors in the OMX IV injection group. Although there was no significant difference in baseline hypoxia between the OMX IT and IV groups, the two groups showed different responses to OMX. In the OMX IV group, hypoxic tumors (n = 5) exhibited significant reductions in tumor hypoxia, as indicated by decreased TMRmax and HV in [18F]FMISO PET imaging after treatment. In contrast, hypoxic tumors in the OMX IT group (n = 6) displayed a significant increase in [18F]FMISO uptake and variable changes in TMRmax and HV. CONCLUSIONS: [18F]FMISO PET/CT imaging presents a promising non-invasive procedure for monitoring tumor hypoxia and assessing the efficacy of hypoxia-modulating therapies in canine patients. OMX has shown promising outcomes in reducing tumor hypoxia, especially when administered intravenously, as evident from reductions in both TMRmax and HV in [18F]FMISO PET imaging.
Assuntos
Doenças do Cão , Misonidazol , Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Hipóxia Tumoral , Animais , Cães , Misonidazol/análogos & derivados , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/veterinária , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/tratamento farmacológico , Feminino , Hipóxia Tumoral/efeitos dos fármacos , Masculino , Neoplasias/veterinária , Neoplasias/tratamento farmacológico , Neoplasias/diagnóstico por imagem , Tiossemicarbazonas/uso terapêutico , Tiossemicarbazonas/farmacologia , Complexos de CoordenaçãoRESUMO
Determining the risk of pathologic fracture in dogs with a primary bone tumor would aid in case selection for in-situ treatment options. Prior research found strong relationships between in vitro strength of canine antebrachii with primary bone tumors and CT-derived metrics. This study assesses the prognosis for pathologic fracture in dogs with distal radial bone tumors using CT-derived structural analysis metrics. CT images of the antebrachium in dogs with aggressive osseous lesions of the radius were used to calculate structural rigidity and failure forces, including axial rigidity (AR), craniocaudal bending rigidity (BR), torsional rigidity (TR), and failure forces for a slightly-curved/asymmetric beam (Fs) or a curved beam (Fc). Metrics were compared with the clinical outcome of radial fracture. Eight of 19 dogs with CT-derived metrics developed a radial fracture. The prognostic potential of the metrics to discriminate fractured and nonfractured bones was analyzed using receiver operating characteristic curves (area under the curve), stepwise logistic regression, and classification regression (CART) analyses. Fc was the most sensitive and specific metric for prognosing fracture occurrence (AUC = 0.864). When dog body weight (BW) was included, all five metrics had AUC > 0.705. Fc was the best predictor of fracture using stepwise logistic regression and CART analysis, followed by BR. An indication of fracture probability can be determined by normalizing Fc or BR with dog BW or by using the logistic regression equation of either metric with dog BW. Results warrant further analysis of a larger cohort to evaluate fracture likelihood in dogs with antebrachial bone neoplasia.
RESUMO
Canine congenital extrahepatic portosystemic shunt (EHPSS) morphologies have not been fully elucidated. The goal of this retrospective, multi-institutional study was to use CT angiography to create an anatomical-based nomenclature system for canine congenital EHPSS. These shunt morphologies were then evaluated to identify any significant association with patient age, sex, breed, weight, or subjective portal perfusion score. Data collected respectively from the SVSTS and VIRIES list-serves included patient DOB, sex, breed, weight, CT date, and reported diagnosis. A single author (C.W.) viewed all CT scans and classified shunts based on the shunt portal vessel(s) of origin, the shunt systemic vessel(s) of insertion, and any substantial portal vessels contributing to the shunt. Additionally, hepatic portal perfusion was subjectively scored between one (poor/none) and five (good/normal) based on the caliber of the intrahepatic portal veins. A total of 1182 CT scans were submitted from 13 different institutions. Due to exclusion criteria, 100 (8.5%) were removed, leaving 1082 CT scans to be included. Forty-five different EHPSS anatomies were identified with five classifications accounting for 85% of all shunts (left gastric-phrenic [27%], left gastric-azygos [19%], left gastric-caval [15%], aberrant left gastric-caval with right gastric vein [12%], and aberrant left gastric-caval with right gastric vein and short gastric vein [11%]). Shunt origin involved the left gastric vein in 95% of the described classifications. Significant differences were identified among the five most common shunt types with respect to age at the time of the CT scan (P < .001), sex (P = .009), breed (P < .001), weight (P < .001), and subjective portal perfusion score (P < .001). An anatomical classification system for canine EHPSS may enable improved understanding, treatment comparisons, and outcome prediction for these patients.
RESUMO
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.
Assuntos
Doenças do Gato , Angiografia por Tomografia Computadorizada , Veia Porta , Animais , Gatos , Angiografia por Tomografia Computadorizada/veterinária , Feminino , Masculino , Veia Porta/anormalidades , Veia Porta/diagnóstico por imagem , Doenças do Gato/diagnóstico por imagem , Sistema Porta/anormalidades , Sistema Porta/diagnóstico por imagem , Malformações Vasculares/veterinária , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/classificaçãoRESUMO
Computed tomography angiography (CTA) is currently the gold standard imaging modality for anatomically characterizing canine hepatic vascular anomalies; with conventional, gadolinium-enhanced MR angiography being less frequently utilized. However, both imaging modalities are limited by a brief, first pass peak of contrast medium in the vasculature that necessitates precisely timed image acquisition. A long-acting purely intravascular magnetic resonance imaging (MRI) contrast agent, ferumoxytol, offers the potential to reduce complexity of magnetic resonance angiography (MRA) protocol planning by ensuring diagnostic contrast medium concentration in all the vessels that are targeted for imaging. Aims of this prospective, pilot, methods comparison study were to develop an optimized MRA protocol using ferumoxytol in dogs with hepatic vascular anomalies, perform a dose escalation trial to compare image quality with four-dose regimens of ferumoxytol, and compare accuracy of vascular anatomic depiction based on the gold standard of CTA. Six dogs (10.7-36.1 kg) with portosystemic shunts (four intrahepatic left divisional shunts and two intrahepatic right divisional shunts) were recruited for inclusion in the study. A dose-escalation trial was performed to compare image quality at four incremental dose levels of ferumoxytol (1, 2, 3, and 4 mg/kg) and to compare the accuracy of vascular anatomic detection to CTA. Ferumoxytol contrast-enhanced MRA (CE-MRA) at 4 mg/kg provided similar conspicuity of normal and abnormal vasculature compared to CTA with a minimal decrease in spatial resolution. Findings indicated that ferumoxytol holds promise for comprehensive, single breath hold CE-MRA of all abdominal vessels in dogs with portosystemic shunts. Background information provided in this study can be used to support development of other future applications such as intracranial and cardiac MRA, real-time imaging, flow quantification, and potentially sedated MRI imaging.
Assuntos
Vasos Sanguíneos/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/veterinária , Cães , Óxido Ferroso-Férrico , Angiografia por Ressonância Magnética/veterinária , Derivação Portossistêmica Transjugular Intra-Hepática/veterinária , Animais , Meios de Contraste , Humanos , Masculino , Estudos ProspectivosRESUMO
Magnetic resonance imaging is the primary method used to diagnose canine glial cell neoplasia and noninfectious inflammatory meningoencephalitis. Subjective differentiation of these diseases can be difficult due to overlapping imaging characteristics. This study utilizes texture analysis (TA) of intra-axial lesions both as a means to quantitatively differentiate these broad categories of disease and to help identify glial tumor grade/cell type and specific meningoencephalitis subtype in a group of 119 dogs with histologically confirmed diagnoses. Fifty-nine dogs with gliomas and 60 dogs with noninfectious inflammatory meningoencephalitis were retrospectively recruited and randomly split into training (n = 80) and test (n = 39) cohorts. Forty-five of 120 texture metrics differed significantly between cohorts after correcting for multiple testing (false discovery rate < 0.05). After training the random forest algorithm, the classification accuracy for the test set was 85% (sensitivity 89%, specificity 81%). TA was only partially able to differentiate the inflammatory subtypes (granulomatous meningoencephalitis [GME], necrotizing meningoencephalitis [NME], and necrotizing leukoencephalitis [NLE]) (out-of-bag error rate of 35.0%) and was unable to identify metrics that could correctly classify glioma grade or cell type (out-of-bag error rate of 59.6% and 47.5%, respectively). Multiple demographic differences, such as patient age, sex, weight, and breed were identified between disease cohorts and subtypes which may be useful in prioritizing differential diagnoses. TA of MR images with a random forest algorithm provided classification accuracy of inflammatory and neoplastic brain disease approaching the accuracy of previously reported subjective radiologist evaluation.
Assuntos
Neoplasias Encefálicas/veterinária , Doenças do Cão/diagnóstico por imagem , Imageamento por Ressonância Magnética/veterinária , Meningoencefalite/veterinária , Animais , Neoplasias Encefálicas/patologia , Doenças do Cão/patologia , Cães , Granuloma/complicações , Masculino , Meningoencefalite/complicações , Meningoencefalite/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Congenital intrahepatic portosystemic shunts (IHPSS) in dogs are traditionally classified as right, left, or central divisional. There are few descriptive studies regarding the variation of IHPSS within these categories. This multicenter, analytical, cross-sectional study aimed to describe a large series of dogs with CT angiography (CTA) of IHPSS, hypothesizing that there would be variation to the existing classification. Ninety CTA studies were assessed for IHPSS type, insertion, and the relationship of the insertion to the primary hepatic veins. Ninety-two percent of IHPSS inserted into a primary hepatic vein (HV) or phrenic vein, 8% inserted directly into the ventral aspect of the intrahepatic caudal vena cava. The most common IHPSS type was a single right divisional (44%), including those inserting via the right lateral HV or the caudate HV. Left divisional IHPSS (33%) inserted into the left HV or left phrenic vein. Central divisional IHPSS (13%) inserted into the quadrate HV, central HV, dorsal right medial HV, or directly into the ventral aspect of the intrahepatic caudal vena cava. Multiple sites of insertion were seen in 9% of dogs. Within left, central, and right divisional types, further subclassifications can therefore commonly be defined based on the hepatic veins with which the shunting vessel communicates. Relating IHPSS morphology to the receiving primary HV could make IHPSS categorization more consistent and may influence the type and method of IHPSS attenuation recommended.
Assuntos
Angiografia por Tomografia Computadorizada/veterinária , Cães/cirurgia , Veias Hepáticas/diagnóstico por imagem , Derivação Portossistêmica Transjugular Intra-Hepática/veterinária , Veia Cava Inferior/diagnóstico por imagem , Animais , Feminino , Veias Hepáticas/cirurgia , Masculino , Derivação Portossistêmica Transjugular Intra-Hepática/estatística & dados numéricos , Veia Cava Inferior/cirurgiaRESUMO
OBJECTIVE: To report the morbidity and mortality associated with adrenalectomy with cavotomy for resection of invasive adrenal neoplasms in dogs and evaluate risk factors for perioperative outcomes. STUDY DESIGN: Retrospective study. ANIMALS: Forty-five client-owned dogs. METHODS: Dogs that underwent open adrenalectomy with cavotomy for resection of adrenal masses with tumor thrombus extending into the vena cava were included. Clinicopathologic data were harvested from medical records. Selected clinical, imaging, and operative variables were statistically evaluated as risk factors for packed red blood cell transfusion, nephrectomy, perioperative death, and overall survival. RESULTS: Thirty-six of 45 masses were pheochromocytomas, 7 were adrenocortical carcinomas, and 2 were unknown type. Caval thrombus terminated prehepatically in 21 of 45 dogs and extended beyond the porta hepatis but terminated prediaphragmatically (intrahepatic prediaphragmatic location) in 15 dogs and thrombi extended postdiaphragmatically in 5 dogs. Thirty-four (76%) dogs were discharged from the hospital, and 11 (24%) dogs died or were euthanized prior to discharge. Median overall survival time for all 45 dogs was 547 days (95%CI 146-710). Bodyweight, tumor type, and size and extent of caval thrombus did not affect survival to discharge, but postdiaphragmatic (rather than prediaphragmatic) thrombus termination was associated with a greater risk of death. CONCLUSION: Long-term survival was common in dogs that survived the perioperative period. Postdiaphragmatic thrombus extension affected the prognosis for overall survival. CLINICAL SIGNIFICANCE: Findings of this study help to stratify operative risk in dogs with adrenal neoplasia and caval invasion.
Assuntos
Neoplasias das Glândulas Suprarrenais/veterinária , Adrenalectomia/veterinária , Carcinoma Adrenocortical/veterinária , Doenças do Cão/cirurgia , Feocromocitoma/veterinária , Neoplasias das Glândulas Suprarrenais/cirurgia , Carcinoma Adrenocortical/cirurgia , Animais , Cães , Feminino , Humanos , Neoplasias Renais/cirurgia , Neoplasias Renais/veterinária , Masculino , Nefrectomia/métodos , Nefrectomia/veterinária , Complicações Pós-Operatórias/veterinária , Prognóstico , Estudos Retrospectivos , Fatores de RiscoRESUMO
Thoracic CT may be used in the workup of patients with pleural effusion. In humans, certain pleural features on CT aid in diagnosing an underlying cause for pleural effusion, whereas this is not well studied in veterinary medicine. This retrospective cross-sectional analytical study assessed pleural and other intrathoracic abnormalities on CT in dogs and cats with pleural effusion and explored potential discriminatory features between effusion types. Eighty-nine dogs and 32 cats with pleural cytology and/or histopathology were categorized into malignant pleural disease (15 dogs and 11 cats), pyothorax (34 dogs and 7 cats), chylothorax (20 dogs and 11 cats), transudative (11 dogs and 2 cats), and hemorrhagic effusion (9 dogs and 1 cat). Multivariable logistic regression analysis comparing malignancy to other effusions found that older patient age (dogs: odds ratio 1.28, P = 0.015; cats: odds ratio 1.53, P = 0.005), nodular diaphragmatic pleural thickening (dogs: odds ratio 7.64, P = 0.021; cats: odds ratio 13.67, P = 0.031), costal pleural masses (dogs: odds ratio 21.50, P = 0.018; cats: odds ratio 32.74, P = 0.019), and pulmonary masses (dogs: odds ratio 44.67, P = 0.002; cats: odds ratio 18.26, P = 0.077) were associated with malignancy. In dogs, any costal pleural abnormality (odds ratio 47.55, P = 0.002) and pulmonary masses (odds ratio 10.05, P = 0.004) were associated with malignancy/pyothorax, whereas any costal pleural abnormality (odds ratio 0.14, P = 0.006) and sternal lymphadenopathy (odds ratio 0.22, P = 0.040) were inversely associated with transudates. There were, however, many overlapping abnormalities between effusion types, so further diagnostic testing remains important for diagnosis.
Assuntos
Doenças do Gato/diagnóstico por imagem , Doenças do Cão/diagnóstico por imagem , Derrame Pleural Maligno/veterinária , Tomografia Computadorizada por Raios X/veterinária , Animais , Doenças do Gato/classificação , Doenças do Gato/diagnóstico , Gatos , Estudos Transversais , Doenças do Cão/classificação , Doenças do Cão/diagnóstico , Cães , Feminino , Masculino , Derrame Pleural Maligno/classificação , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/diagnóstico por imagem , Estudos RetrospectivosRESUMO
Published studies on the use of stereotactic radiotherapy for dogs with pituitary tumors are limited. This retrospective observational study describes results of stereotactic radiotherapy for 45 dogs with imaging-diagnosed pituitary tumors. All dogs were treated at a single hospital during the period of December 2009-2015. The stereotactic radiotherapy was delivered in one 15 Gray (Gy) fraction or in three 8 Gy fractions. At the time of analysis, 41 dogs were deceased. Four were alive and censored from all survival analyses; one dog received 8 Gy every other day and was removed from protocol analyses. The median overall survival from first treatment was 311 days (95% confidence interval 226-410 days [range 1-2134 days]). Thirty-two dogs received 15 Gy (median overall survival 311 days; 95% confidence interval [range 221-427 days]), and 12 received 24 Gy on three consecutive days (median overall survival 245 days, 95% confidence interval [range 2-626 days]). Twenty-nine dogs had hyperadrenocorticism (median overall survival 245 days), while 16 had nonfunctional masses (median overall survival 626 days). Clinical improvement was reported in 37/45 cases. Presumptive signs of acute adverse effects within 4 months of stereotactic radiotherapy were noted in 10/45, and most had improvement spontaneously or with steroids. Late effects versus tumor progression were not discernable, but posttreatment blindness (2), hypernatremia (2), and progressive neurological signs (31) were reported. There was no statistical difference in median overall survival for different protocols. Patients with nonfunctional masses had longer median overall survival than those with hyperadrenocorticism (P = 0.0003). Survival outcomes with stereotactic radiotherapy were shorter than those previously reported with definitive radiation, especially for dogs with hyperadrenocorticism.
Assuntos
Hiperfunção Adrenocortical/veterinária , Doenças do Cão/radioterapia , Neoplasias Hipofisárias/veterinária , Radiocirurgia/veterinária , Hiperfunção Adrenocortical/radioterapia , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Feminino , Masculino , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/radioterapia , Doses de Radiação , Radiocirurgia/métodos , Estudos Retrospectivos , Análise de SobrevidaRESUMO
Complete assessment of vertebral trauma in dogs currently requires CT and MRI for evaluation of the osseous and soft tissue structures that contribute to vertebral stability. Some studies in people have suggested that MRI may be sensitive and specific at detecting vertebral fractures making this potentially a single modality that could be used in spinal trauma evaluation. This study aimed to assess the ability for observers to evaluate vertebral fractures using MRI when compared to CT, which was used as the reference standard. Twenty-nine dogs with previously diagnosed acute vertebral fractures and four dogs with no vertebral fracture that had undergone sequential CT and MRI were included into the study. One hundred twenty-eight vertebrae were evaluated for the presence of fractures. Imaging studies were read by two observers blinded to the history. While both observers had similarly high sensitivity and specificity for simple detection of any fractured vertebrae, interobserver agreement was only moderate (κ = 0.584). When evaluations were specifically limited to detection of structurally unstable fractured vertebrae both observers showed improved specificity and interobserver agreement became substantial (κ = 0.650). Complete agreement for exact fracture location between MRI and CT results was only achieved in 14.3-32.6% of fractured vertebra with up to 79% of fractures being missed in some vertebral structures. This suggests that although MRI may be able to detect the presence of fractured vertebrae, it is not able to replace CT for the complete evaluation of the traumatized spine and documentation of fracture morphology.
Assuntos
Doenças do Cão/diagnóstico , Imageamento por Ressonância Magnética/veterinária , Fraturas da Coluna Vertebral/veterinária , Tomografia Computadorizada por Raios X/veterinária , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Feminino , Imageamento por Ressonância Magnética/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fraturas da Coluna Vertebral/diagnóstico , Fraturas da Coluna Vertebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodosRESUMO
OBJECTIVE: To describe the ocular anatomy of the black pacu (Colossoma macropomum), a freshwater teleost fish of the Amazon River basin, including an unusual choroid laden with adipose tissue. PROCEDURES: Three adult black pacu were anesthetized and examined clinically and with ocular ultrasonography, then euthanized. Three fish were euthanized and their heads imaged immediately postmortem using computed tomography. One fish was euthanized and its exenterated eyes imaged by high-resolution magnetic resonance imaging. The exenterated eyes of all seven fish were fixed in formalin; eyes from three fish were examined grossly and histologically. Additionally, archived histologic sections from two smaller black pacu specimens were examined. RESULTS: Findings were consistent among the ocular imaging modalities used. Intrinsic to the sclera were circumferential ossicles and scleral cartilage. The lens was spherical and protruded through the ovoid pupil with an aphakic space inferiorly when the accommodative mechanism was relaxed under anesthesia. Both a small falciform process and epiretinal vasculature were present in the posterior segment. The retina was cone-rich, and processes of the retinal pigment epithelium enveloped the photoreceptor outer segments. Remarkably, the choroid occupied one-third of the anteroposterior length of the globe; histology confirmed that the bulk of the choroid was composed of adipose tissue. CONCLUSIONS: The eye of the pacu overall is typical of teleosts but has the notable and consistent finding of a substantive store of choroidal fat of unknown function.
Assuntos
Olho/anatomia & histologia , Peixes/anatomia & histologia , Animais , Olho/diagnóstico por imagem , Imageamento por Ressonância Magnética/veterinária , Tomografia Computadorizada por Raios X/veterináriaRESUMO
OBJECTIVE: To describe a technique for tumor thrombectomy by phrenicoabdominal venotomy in dogs with adrenal neoplasia and suspected caval invasion and to report complications and outcomes associated with the procedure. STUDY DESIGN: Retrospective case series. ANIMALS: Eight client-owned dogs with invasive adrenal tumors. METHODS: Medical records of dogs diagnosed with adrenal tumors with extension of thrombus into the phrenicoabdominal vein (PAV) and vena cava were reviewed. Cases where phrenicoabdominal venotomy without cavotomy for thrombus resection was performed were included. Data collected from the medical records included signalment, clinical signs, physical examination findings, diagnostic imaging results, preoperative laboratory testing, surgical technique, surgical and postoperative complications and outcome. RESULTS: Phrenicoabdominal venotomy was successful in removal of vena caval thrombosis in 7 of 8 dogs. In one case, an attempt was made to remove a large vena caval thrombus through a distended PAV resulting in fragmentation of the thrombus and the need to extend the incision into the vena cava. In all dogs, complete removal of tumor thrombus was achieved. Two dogs died in the perioperative period, one from cardiopulmonary arrest and a second from bronchopneumonia and pancreatitis. The remaining 6 dogs were discharged from the hospital. CONCLUSION: Thrombectomy through a phrenicoabdominal venotomy may obviate the need for a cavotomy in a subset of dogs with invasive adrenal neoplasia.
Assuntos
Neoplasias das Glândulas Suprarrenais/veterinária , Adrenalectomia/veterinária , Carcinoma Adrenocortical/veterinária , Doenças do Cão/cirurgia , Trombectomia/veterinária , Veia Cava Inferior/cirurgia , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/patologia , Neoplasias das Glândulas Suprarrenais/cirurgia , Adrenalectomia/métodos , Carcinoma Adrenocortical/diagnóstico por imagem , Carcinoma Adrenocortical/secundário , Carcinoma Adrenocortical/cirurgia , Animais , Cães , Feminino , Masculino , Metástase Neoplásica , Complicações Pós-Operatórias/veterinária , Estudos Retrospectivos , Trombectomia/métodos , Tomografia Computadorizada por Raios X/veterinária , Veia Cava Inferior/diagnóstico por imagem , Veia Cava Inferior/patologiaRESUMO
OBJECTIVE: To report outcome and complications after percutaneous transvenous coil embolization (PTCE) and evaluate the clinical, laboratory, and imaging changes in dogs with intrahepatic portosystemic shunts (IHPSS) pre-PTCE and post-PTCE. STUDY DESIGN: Prospective clinical trial. ANIMALS: Twenty-five dogs (15 dogs in imaging subgroup) with IHPSS. METHODS: Clinical signs, hematologic, and biochemical parameters were recorded before and 3 months after PTCE. All dogs received the same medical treatment and underwent PTCE. In the imaging subgroup, ultrasonography, hepatic portal scintigraphy, and computed tomography-angiography were performed pre-PTCE and post-PTCE. RESULTS: All evaluated bloodwork values improved by at least 50% of their initial value, by 3 months post-PTCE. Liver volume increased after PTCE (P = .001), but remained lower than normal in 11/15 dogs. Hepatic arterial fraction decreased after PTCE (P = .029), consistent with increased portal blood flow to the liver. Twenty-four of 25 dogs were available for reevaluation at 3 months, and all abnormal clinical signs had resolved in 22/24 dogs. CONCLUSION: PTCE appears promising as a treatment for IHPSS, as clinical signs resolved in most cases, bloodwork abnormalities often normalized, and the procedure was performed safely with minimal complications. PTCE increased hepatic portal perfusion and liver volume in most dogs. These promising results justify a future randomized clinical trial comparing PTCE, other attenuation options, and medical management alone.
Assuntos
Cateterismo Venoso Central/veterinária , Doenças do Cão/terapia , Embolização Terapêutica/veterinária , Veia Porta/anormalidades , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Feminino , Fígado/irrigação sanguínea , Fígado/diagnóstico por imagem , Masculino , Sistema Porta/cirurgia , Veia Porta/patologia , Veia Porta/cirurgia , Derivação Portossistêmica Cirúrgica , Estudos Prospectivos , Cintilografia , Stents , UltrassonografiaRESUMO
Exact target volume definition is an essential prerequisite for modern radiotherapy treatment planning. Contouring the gross tumor volume of brain tumors on computed tomography (CT) images coregistered with magnetic resonance images is standard practice in human medicine. In this retrospective study, including only cases with an imaging diagnosis of meningioma, we hypothesized that the gross tumor volume contoured from the contrast-enhanced magnetic resonance imaging (MRI) (gross tumor volume-MRI) is larger when compared to the gross tumor volume contoured using contrast-enhanced CT (gross tumor volume-CT). A total of 22 dogs were included in the study. Interestingly, there was a significant statistical difference between the gross tumor volume-CT and the gross tumor volume-MRI (P = 0.001). The gross tumor volume-MRI was larger than the gross tumor volume-CT in all, but two cases. The mean ratio between gross tumor volume-MRI and gross tumor volume-CT was 1.43 (range 0.84-4.00). The mean overlap between gross tumor volume-CT and gross tumor volume-MRI was 68% (range 22-86%), while a mean of 26% of the composite gross tumor volume was defined only by MRI (range 4-76%) and a mean of 6% only by CT (range 0-22%). These findings suggest that CT and MRI are complementary modalities in radiation planning of meningiomas and their composite volume should be used to avoid geographical miss of neoplastic tissue. When the MRI is not available for planning, a margin of 0.3 cm around the gross tumor volume-CT could reduce the probability of a geographical miss. However, such numerical correction cannot be applied to the clinical practice until it is validated in a properly designed treatment planning study.
Assuntos
Doenças do Cão/radioterapia , Neoplasias Meníngeas/veterinária , Meningioma/veterinária , Planejamento da Radioterapia Assistida por Computador/veterinária , Radioterapia Conformacional/veterinária , Animais , Cães , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/veterinária , Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/veterináriaRESUMO
BACKGROUND: Early signs of canine transitional cell carcinoma (TCC) are frequently assumed to be caused by other lower urinary tract diseases (LUTD) such as urinary tract infections, resulting in late diagnosis of TCC which could be fatal. The development of a non-invasive clinical test for TCC could dramatically reduce mortality. To determine whether microRNAs (miRNAs) can be used as non-invasive diagnostic biomarkers, we assessed miRNA expression in blood and/or urine from dogs with clinically normal bladders (n = 28), LUTD (n = 25), and TCC (n = 17). Expression levels of 5 miRNA associated with TCC pathophysiology (miR-34a, let-7c, miR-16, miR-103b, and miR-106b) were assessed by quantitative real-time PCR. RESULTS: Statistical analyses using ranked ANOVA identified significant differences in miR-103b and miR-16 levels between urine samples from LUTD and TCC patients (miR-103b, p = 0.002; and miR-16, p = 0.016). No statistically significant differences in miRNA levels were observed between blood samples from LUTD versus TCC patients. Expression levels of miR-34a trended with miR-16, let-7c, and miR-103b levels in individual normal urine samples, however, this coordination was completely lost in TCC urine samples. In contrast, co-ordination of miR-34a, miR-16, let-7c, and miR-103b expression levels was maintained in blood samples from TCC patients. CONCLUSIONS: Our combined data indicate a potential role for miR-103b and miR-16 as diagnostic urine biomarkers for TCC, and that further investigation of miR-103b and miR-16 in the dysregulation of coordinated miRNA expression in bladder carcinogenesis is warranted.
Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células de Transição/veterinária , Doenças do Cão/metabolismo , MicroRNAs/metabolismo , Neoplasias da Bexiga Urinária/veterinária , Animais , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Carcinoma de Células de Transição/metabolismo , Doenças do Cão/sangue , Doenças do Cão/urina , Cães , Estudos de Viabilidade , Feminino , Masculino , MicroRNAs/urina , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Neoplasias da Bexiga Urinária/metabolismoRESUMO
OBJECTIVE: To characterize grossly, histologically, and via computed tomography (CT) the appearance of intrascleral cartilage, bone, or both in domestic goats with otherwise normal eyes and to correlate this with age, sex, and breed. ANIMALS STUDIED: Sixty-eight domestic goats (89 eyes). PROCEDURES: Forty-nine formalin-fixed globes from 38 goats underwent high-resolution CT, and gross and light microscopic examination. An additional 40 eyes from 30 goats underwent light microscopy only. Age, breed, and sex of affected goats were retrieved from medical records. RESULTS: Considering all methods of evaluation collectively, cartilage was detected in 42% of eyes (44% of goats) and bone in 11% of eyes (12% of goats); bone was never seen without cartilage. Goats in which bone, cartilage, or both were detected ranged from 0.25 to 13 (median = 3.5) years of age, represented 11 of 12 breeds of the study population, and had a male:female ratio of 11:19. Bone was detected in the eyes of significantly more males (n = 8) than females (n = 2). No sex predilection was noted for cartilage alone. Histology revealed intrascleral chondrocyte-like cells, hyaline cartilage, and islands of lamellar bone. Some regions of bone had central, adipose-rich, marrow-like cavities. CT localized mineralized tissue as adjacent to or partially surrounding the optic nerve head. CONCLUSIONS: This is the first report of intrascleral bone or cartilage in a normal goat and of intrascleral bone in an otherwise normal mammal. The high prevalence of intrascleral cartilage and bone in this study suggests that this finding is normal and likely represents an adaptation in goats.
Assuntos
Osso e Ossos/anatomia & histologia , Cartilagem/anatomia & histologia , Cabras/anatomia & histologia , Esclera/anatomia & histologia , Fatores Etários , Animais , Feminino , Masculino , Microscopia/veterinária , Esclera/diagnóstico por imagem , Fatores Sexuais , Especificidade da Espécie , Tomografia Computadorizada por Raios X/veterináriaRESUMO
OBJECTIVE: To improve the prediction of fractures in dogs with bone tumors of the distal radius by identifying computed tomography (CT) indices that correlate with antebrachial bone strength and fracture location. STUDY DESIGN: Prospective experimental study. ANIMALS: Dogs with antebrachial osteosarcoma (n = 10), and normal cadaver bones (n=9). METHODS: Antebrachia were imaged with quantitative CT prior to biomechanical testing to failure. CT indices of structural properties were compared to yield force and maximum force using Pearson correlation tests. RESULTS: Straight beam failure (Fs), axial rigidity, curved beam failure (Fc), and craniocaudal bending moment of inertia (MOICrCd) CT indices most highly correlated (0.77 > R > 0.57) with yield and maximum forces when iOSA-affected and control bones were included in the analysis. Considering only OSA-affected bones, Fs, Fc, and axial rigidity correlated highly (0.85 > R > 0.80) with maximum force. In affected bones, the location of minimum axial rigidity and maximum MOICrCd correlated highly (R > 0.85) with the actual fracture location. CONCLUSIONS: CT-derived axial rigidity, Fs, and MOICrCd have strong linear relationships with yield and maximum force. These indices should be further evaluated prospectively in OSA-affected dogs that do, and do not, experience pathologic fracture.
Assuntos
Doenças do Cão/etiologia , Fraturas Ósseas/veterinária , Fraturas Espontâneas/veterinária , Osteossarcoma/veterinária , Tomografia Computadorizada por Raios X/veterinária , Animais , Fenômenos Biomecânicos , Cadáver , Doenças do Cão/patologia , Cães , Fraturas Ósseas/patologia , Humanos , Osteossarcoma/complicações , Osteossarcoma/patologia , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodosRESUMO
OBJECTIVE: To determine the influence of neoplasia on the biomechanical properties of canine antebrachia. STUDY DESIGN: Ex vivo biomechanical study. SAMPLE POPULATION: Osteosarcoma (OSA)-affected canine antebrachia (n = 12) and unaffected canine antebrachia (n = 9). METHODS: Antebrachia were compressed in axial loading until failure. A load-deformation curve was used to acquire the structural mechanical properties of neoplastic and unaffected specimens. Structural properties and properties normalized by body weight (BW) and radius length were compared using analysis of variance (ANOVA). Modes of failure were compared descriptively. RESULTS: Neoplastic antebrachia fractured at, or adjacent to, the OSA in the distal radial diaphysis. Unaffected antebrachia failed via mid-diaphyseal radial fractures with a transverse cranial component and an oblique caudal component. Structural mechanical properties were more variable in neoplastic antebrachia than unaffected antebrachia, which was partially attributable to differences in bone geometry related to dog size. When normalized by dog BW and radial length, strength, stiffness, and energy to yield and failure, were lower in neoplastic antebrachia than in unaffected antebrachia. CONCLUSIONS: OSA of the distal radial metaphysis in dogs presented for limb amputation markedly compromises the structural integrity of affected antebrachia. However, biomechanical properties of affected bones was sufficient for weight-bearing, as none of the neoplastic antebrachia fractured before amputation. The behavior of tumor invaded bone under cyclic loading warrants further investigations to evaluate the viability of in situ therapies for bone tumors in dogs.
Assuntos
Doenças do Cão/patologia , Membro Anterior/patologia , Osteossarcoma/veterinária , Animais , Fenômenos Biomecânicos , Cadáver , Cães , Osteossarcoma/patologia , Pressão , Suporte de CargaRESUMO
Companion rats are often presented to veterinarians for respiratory difficulties. Dyspnea in rats is most commonly due to infectious pneumonia, and thoracic neoplasia can go undiagnosed ante mortem due to a mistaken interpretation of pneumonia. In domestic carnivores, pulmonary nodular patterns have been shown to correlate with lung neoplastic diseases and infectious diseases. The main objective of this retrospective case series study was to determine whether certain radiographic criteria could be correlated with the presence of thoracic infectious disease and neoplastic disease in companion rats. A secondary objective was to determine whether the patient's sex and age were different between rats diagnosed with infectious versus neoplastic disease. Medical records and thoracic radiographs of dyspneic companion rats presented to the University of California at Davis, William R. Pritchard Veterinary Medical Teaching Hospital during the time period from January 2000 to December 2014 were reviewed. Rats with postmortem confirmation of thoracic lesions were included in the study. Thoracic radiographs were evaluated for positioning, lesion distribution, lung lobe involved, pulmonary pattern, mediastinal and pleural lesions by three observers blinded to diagnosis. Thirty rats were included in the study, including 23 rats with an infectious disease and seven with neoplasia. Mediastinal lesions were significantly more prevalent in the group diagnosed with thoracic neoplasia (P = 0.031), in particular cranially (P = 0.048). Although there was an overlap between the two groups, findings indicated that the presence of cranial mediastinal lesions may be helpful for differentiating neoplastic from infectious disease in rats.