Asunto(s)
Enfermedades de los Perros/diagnóstico , Tumores Venéreos Veterinarios/diagnóstico , Animales , Enfermedades de los Perros/diagnóstico por imagen , Enfermedades de los Perros/patología , Perros , Femenino , Radiografía , Tumores Venéreos Veterinarios/diagnóstico por imagen , Tumores Venéreos Veterinarios/patologíaRESUMEN
Conflicting information has been published regarding the cause of a valentine-shaped cardiac silhouette in dorsoventral or ventrodorsal thoracic radiographs in cats. The purpose of this retrospective, cross-sectional study was to test the hypothesis that the valentine shape is primarily due to left atrial enlargement. Images for cats with a radiographic valentine-shaped cardiac silhouette and full echocardiography examination were retrieved and independently reviewed. A subjective scoring system was used to record severity of radiographic valentine shape. Subjective radiographic evidence of left atrial enlargement in a radiographic lateral projection and a final diagnosis based on medical records were also recorded. A total of 81 cats met inclusion criteria. There was a strong positive correlation (P < 0.001) between echocardiographic left atrial size and severity of radiographic valentine shape. There was no effect of echocardiographic right atrial size on the severity of valentine shape, except when concurrent with severe left atrial enlargement. In this situation, right atrial enlargement increased the likelihood of observing a severe valentine shape. There was no effect of right atrial enlargement on the shape of the cardiac silhouette when left atrial enlargement was absent or only mild to moderate. There was no correlation between the category of final diagnosis of cardiac disease and the severity of valentine shape. Findings from this study supported the hypothesis that a valentine-shaped cardiac silhouette in radiographs is due primarily to left atrial enlargement in cats, with right atrial enlargement only impacting the shape if concurrent with severe left atrial enlargement.
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Cardiomegalia/veterinaria , Enfermedades de los Gatos/diagnóstico por imagen , Atrios Cardíacos/diagnóstico por imagen , Animales , Cardiomegalia/diagnóstico por imagen , Cardiomegalia/etiología , Enfermedades de los Gatos/etiología , Gatos , Estudios Transversales , Ecocardiografía/veterinaria , Femenino , Masculino , North Carolina , Radiografía , Estudios RetrospectivosRESUMEN
The purpose of this retrospective study was to describe pre- and postcontrast computed tomographic (CT) characteristics of confirmed nonparenchymal hemangiosarcoma in a group of dogs. Medical records were searched during the period of July 2003 and October 2011 and dogs with histologically confirmed nonparenchymal hemangiosarcoma and pre- and postcontrast CT images were recruited. Two observers recorded a consensus opinion for the following CT characteristics for each dog: largest transverse tumor diameter, number of masses, general tumor shape, character of the tumor margin, precontrast appearance, presence of dystrophic calcification, presence of postcontrast enhancement, pattern of postcontrast enhancement, presence of regional lymphadenopathy, and presence of associated cavitary fluid. A total of 17 dogs met inclusion criteria. Tumors were located in the nasal cavity, muscle, mandible, mesentery, subcutaneous tissue, and retroperitoneal space. Computed tomographic features of nonparenchymal hemangiosarcoma were similar to those of other soft tissue sarcomas, with most tumors being heterogeneous in precontrast images, invasive into adjacent tissue, and heterogeneously contrast enhancing. One unexpected finding was the presence of intense foci of contrast enhancement in 13 of the 17 tumors (76%). This appearance, which is not typical of other soft tissue sarcomas, was consistent with contrast medium residing in vascular channels. Findings indicated that there were no unique distinguishing CT characteristics for nonparenchymal hemangiosarcoma in dogs; however, the presence of highly attenuating foci of contrast enhancement may warrant further investigation in prospective diagnostic sensitivity and treatment outcome studies.
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Enfermedades de los Perros/diagnóstico por imagen , Hemangiosarcoma/veterinaria , Tomografía Computarizada por Rayos X/veterinaria , Animales , Medios de Contraste , Enfermedades de los Perros/etiología , Enfermedades de los Perros/patología , Perros , Femenino , Hemangiosarcoma/diagnóstico por imagen , Hemangiosarcoma/etiología , Hemangiosarcoma/patología , Masculino , Estudios RetrospectivosRESUMEN
Understanding radiographic anatomy and the effects of varying patient and radiographic tube positioning on image quality can be a challenge for students. The purposes of this study were to develop and validate a novel technique for creating simulated radiographs using computed tomography (CT) datasets. A DICOM viewer (ORS Visual) plug-in was developed with the ability to move and deform cuboidal volumetric CT datasets, and to produce images simulating the effects of tube-patient-detector distance and angulation. Computed tomographic datasets were acquired from two dogs, one cat, and one horse. Simulated radiographs of different body parts (n = 9) were produced using different angles to mimic conventional projections, before actual digital radiographs were obtained using the same projections. These studies (n = 18) were then submitted to 10 board-certified radiologists who were asked to score visualization of anatomical landmarks, depiction of patient positioning, realism of distortion/magnification, and image quality. No significant differences between simulated and actual radiographs were found for anatomic structure visualization and patient positioning in the majority of body parts. For the assessment of radiographic realism, no significant differences were found between simulated and digital radiographs for canine pelvis, equine tarsus, and feline abdomen body parts. Overall, image quality and contrast resolution of simulated radiographs were considered satisfactory. Findings from the current study indicated that radiographs simulated using this new technique are comparable to actual digital radiographs. Further studies are needed to apply this technique in developing interactive tools for teaching radiographic anatomy and the effects of varying patient and tube positioning.
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Gatos/anatomía & histología , Perros/anatomía & histología , Caballos/anatomía & histología , Tomografía Computarizada por Rayos X/veterinaria , Animales , Simulación por Computador , Femenino , Masculino , Valores de ReferenciaRESUMEN
Discrete discoid or linear areas of increased soft opacity have been observed within the pulmonary parenchyma in thoracic radiographs of dogs and cats. Similar radiographic findings have been described in humans and termed plate-like atelectasis. The purpose of this retrospective study was to describe locations and characteristics of presumed plate-like atelectasis, presence of concurrent thoracic disease(s), and presence of persistent pulmonary changes on recheck thoracic radiographic studies in a cohort of dogs and cats. Hospital records between 2004 and 2011 were searched and a total of 90 cases were included (75 dogs and 15 cats, 2-17 years of age). Plate-like atelectasis was most commonly found in left lateral radiographs. Plate-like atelectasis was observed in the cranial thorax and was oriented in a dorsocranial to ventrocaudal direction in 68 (75%) patients. Plate-like atelectasis averaged 29.6 ± 14.4 mm in length and 2.6 ± 1.3 mm in width. In 57 of the 90 patients (63%), plate-like atelectasis was the only abnormality found. Plate-like atelectasis was present in 7 of 22 cases where follow-up radiographs were available. Findings from the current study indicated that, while the etiology of plate-like atelectasis remains unknown, anatomic variations in sublobar pulmonary anatomy might account for pleural areas of atelectasis. The authors propose that the presence of plate-like atelectasis may represent areas of atelectasis that track along sublobar lung lobe separations, an area of hypoventilation or decreased collateral ventilation, and/or area of decreased localized surfactant deficiency.
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Enfermedades de los Gatos/diagnóstico por imagen , Enfermedades de los Perros/diagnóstico por imagen , Pulmón/patología , Atelectasia Pulmonar/veterinaria , Animales , Enfermedades de los Gatos/patología , Gatos , Enfermedades de los Perros/patología , Perros , Femenino , Pulmón/diagnóstico por imagen , Masculino , Atelectasia Pulmonar/diagnóstico por imagen , Atelectasia Pulmonar/patología , Radiografía Torácica/veterinaria , Estudios RetrospectivosRESUMEN
It is important to optimize digital radiographic technique settings for small animal imaging in order to maximize image quality while minimizing radiation exposure to personnel. The purpose of this study was to evaluate two objective methods for determining optimal kVp values for an indirect flat panel digital detector. One method considered both image quality and personnel exposure as endpoints and one considered only image quality. Phantoms simulated veterinary patients of varying thicknesses with lesions of varying sizes. Phantoms were exposed to a range of kVp values (60, 81, 100, and 121), using different mAs settings for each phantom. Additionally, all phantoms were exposed to a standard test exposure of 100 kVp/2.5 mAs. Scattered radiation was recorded and used as a measure of personnel exposure. When personnel exposure was considered, a figure of merit was calculated as an endpoint of optimization. The optimal kVp value for each phantom was determined based on the highest signal difference-to-noise ratio with or without inclusion of the figure of merit. When personnel exposure was not considered, increasing kVp resulted in higher signal difference-to-noise ratios and personnel exposure increased when both patient thickness and kVp increased. Findings indicated that a single standard technique of 100 kVp/2.5 mAs was only optimal for most medium-sized patients. Images of thinner patients should be made with a lower kVp. Very large patients require a higher kVp than 100 regardless of the optimization method used. Personnel exposure from optimized techniques was low and not expected to exceed annual occupational dose limits.
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Técnicos de Animales , Exposición Profesional/prevención & control , Fantasmas de Imagen/normas , Monitoreo de Radiación/instrumentación , Intensificación de Imagen Radiográfica/métodos , Animales , Humanos , Fantasmas de Imagen/veterinaria , Control de Calidad , Dosis de Radiación , Monitoreo de Radiación/métodos , Intensificación de Imagen Radiográfica/instrumentación , Valores de Referencia , Relación Señal-RuidoRESUMEN
PURPOSE: It is unknown whether a thermal dose should be administered using a few large fractions with higher temperatures or a larger number of fractions with lower temperatures. To evaluate this we assessed the effect of administering the same total thermal dose, approximately 30 CEM43T(90), in one versus three to four fractions per week, over 5 weeks. MATERIALS AND METHODS: Canine sarcomas were randomised to receive one of the hyperthermia fractionation schemes along with fractionated radiotherapy. Tumour response was based on changes in tumour volume, oxygenation, water diffusion quantified using MRI, and a panel of histological and immunohistochemical end points. RESULTS: There was a greater reduction in tumour volume and water diffusion at the end of therapy in tumours receiving one hyperthermia fraction per week. There was a weak but significant association between improved tumour oxygenation 24 h after the first hyperthermia treatment and extent of volume reduction at the end of therapy. Finally, the direction of change of HIF-1α and CA-IX immunoreactivity after the first hyperthermia fraction was similar and there was an inverse relationship between temperature and the direction of change of CA-IX. There were no significant changes in interstitial fluid pressure, VEGF, vWF, apoptosis or necrosis as a function of treatment group or temperature. CONCLUSIONS: We did not identify an advantage to a three to four per week hyperthermia prescription, and response data pointed to a one per week prescription being superior.
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Hipertermia Inducida , Sarcoma/terapia , Neoplasias de los Tejidos Blandos/terapia , Animales , Antígenos de Neoplasias/metabolismo , Anhidrasas Carbónicas/metabolismo , Caspasa 3/metabolismo , Perros , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Sarcoma/metabolismo , Sarcoma/patología , Neoplasias de los Tejidos Blandos/metabolismo , Neoplasias de los Tejidos Blandos/patología , Carga Tumoral , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Single-shot turbo spin-echo sequences are heavily T2-weighted sequences that are exceptionally well suited to evaluate the subarachnoid space. In the T2-weighted fast spin-echo sequences that are used routinely in spinal magnetic resonance (MR) imaging, the subarachnoid space is not well differentiated from the surrounding epidural fat, which could lead to decreased detection of lesions of the subarachnoid space such as arachnoid diverticula. Our purpose was to determine the added value of a single-shot turbo spin-echo sequence in identifying cystic lesions of the subarachnoid space in dogs. MR images of six dogs with a confirmed arachnoid diverticulum and 24 dogs with other spinal disease were included. Six observers were asked to interpret only T2-weighted images initially, and in a second session, T2-weighted and half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences. The MR images were anonymized, and no signalment, history, or clinical information was provided. Without the HASTE sequences, 25% of arachnoid diverticula were identified. Adding the HASTE sequence increased the diagnosis of arachnoid diverticulum to 52.8%. The resulting difference, after adding the HASTE sequence, of 27.8% was statistically significant (P = 0.002). No false-positive diagnoses of arachnoid diverticulum were made with either sequence. Although sensitivity in this study was likely artificially low, the significantly increased detection rate of arachnoid diverticula when using HASTE imaging indicates that this sequence is a valuable addition to MR imaging protocols for the canine spine.
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Quistes Aracnoideos/veterinaria , Enfermedades de los Perros/diagnóstico , Imagen por Resonancia Magnética/veterinaria , Animales , Quistes Aracnoideos/diagnóstico , Perros , Imagen por Resonancia Magnética/métodosRESUMEN
Advances in magnetic resonance (MR) imaging and three-dimensional (3D) modeling software provide the tools necessary to create sophisticated, interactive anatomic resources that can assist in the interpretation of MR images of extremities, and learning the structure and function of limb musculature. Modeling provides advantages over dissection or consultation of print atlases because of the associated speed, flexibility, 3D nature, and elimination of superimposed arrows and labels. Our goals were to create a diagnostic atlas of pelvic limb muscles that will facilitate interpretation of MR images of patients with muscle injury and to create a 3D model of the canine pelvic limb musculature to facilitate anatomic learning. To create these resources, we used structural segmentation of MR images, a process that groups image pixels into anatomically meaningful regions. The Diagnostic Atlas is an interactive, multiplanar, web-based MR atlas of the canine pelvic limb musculature that was created by manually segmenting clinically analogous MR sequences. Higher resolution volumetric MR and computed tomography (CT) data were segmented into separately labeled volumes of data and then transformed into a multilayered 3D computer model. The 3D Model serves as a resource for students of gross anatomy, encouraging integrative learning with its highly interactive and selective display capabilities. For clinicians, the 3D Model also serves to bridge the gap between topographic and tomographic anatomy, displaying both formats alongside, or even superimposed over each other. Both projects are hosted on an open-access website, http://3dvetanatomy.ncsu.edu/
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Simulación por Computador , Perros/anatomía & histología , Imagen por Resonancia Magnética/veterinaria , Músculo Esquelético/anatomía & histología , Pelvis , Tomografía Computarizada por Rayos X/veterinaria , Animales , Músculo Esquelético/diagnóstico por imagenRESUMEN
Pulsatile venous flow in the internal vertebral venous plexus of the cervical spine can lead to vertical, linear T2-hyperintensities in the spinal cord at the cranial aspect of C3 and C4 in transverse T2-weighted images in large breed dogs that are not accompanied by ghosting. The artifact is more conspicuous in pre- and postcontrast transverse T1-weighted images and is accompanied by ghosting in that sequence, typical of a pulsatility artifact. A flow-related artifact was confirmed as the cause for this appearance by noting its absence after either exchange of phase and frequency encoding direction or by flow compensation. Care should be exercised to avoid misdiagnosing this pulsatility artifact seen in transverse T2-weighted images of the midcervical spine in large dogs as an intramedullary lesion when T1-images or phase-swap images are not available to confirm its artifactual origin.
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Artefactos , Vértebras Cervicales , Enfermedades de los Perros/diagnóstico , Imagen por Resonancia Magnética/veterinaria , Enfermedades de la Médula Espinal/veterinaria , Médula Espinal/irrigación sanguínea , Animales , Perros , Flujo Pulsátil , Médula Espinal/patología , Enfermedades de la Médula Espinal/diagnósticoRESUMEN
Myelography, computed tomography (CT), and magnetic resonance (MR) imaging are the diagnostic modalities currently used in the evaluation of dogs with suspected disc herniation. Where high-field MR imaging is available, it is considered the optimal modality for any myelopathy in dogs, including those with disc disease. CT myelography may be the next best option, particularly in nonchondrodystrophoid dogs. In chondrodystrophoid dogs, in which extrusion of mineralized disc material is common, plain CT will enable diagnosis in most cases. Myelography is still considered adequate for diagnosis of disc herniation when MR and CT are unavailable.
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Enfermedades de los Perros/diagnóstico , Desplazamiento del Disco Intervertebral/veterinaria , Imagen por Resonancia Magnética/veterinaria , Mielografía/veterinaria , Tomografía Computarizada por Rayos X/veterinaria , Animales , Perros , Desplazamiento del Disco Intervertebral/diagnóstico , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodosRESUMEN
PURPOSE: While hyperthermia is an effective adjuvant treatment to radiotherapy, we do not completely understand the nature of the response heterogeneity. EXPERIMENTAL DESIGN: We performed gene expression analysis of 22 spontaneous canine sarcomas before and after the first hyperthermia treatment administered as an adjuvant to radiotherapy. In parallel, diffusion-weighted MRI (DWI) was done prior to the treatment course and at the end of therapy. RESULTS: From the integrative analysis of gene expression and DWI, we identified significant correlation between tumor responses with genes involved in VEGF signaling, telomerase, DNA repair, and inflammation. The treatment-induced changes in gene expression identified 2 distinct tumor subtypes with significant differences in their gene expression and treatment response, as defined by changes in DWI. The 2 tumor subtypes could also be readily identified by pretreatment gene expression. The tumor subtypes, with stronger expression response and DWI increase, had higher levels of HSP70, POT1, and centrosomal proteins, and lower levels of CD31, vWF, and transferrin. Such differential gene expression between the 2 subtypes was used to interrogate connectivity map and identify linkages to an HSP90 inhibitor, geldanamycin. We further validated the ability of geldanamycin to enhance cell killing of human tumor cells with hyperthermia and radiotherapy in clonogenic assays. CONCLUSIONS: To our knowledge, this is one of the first successful attempts to link changes in gene expression and functional imaging to understand the response heterogeneity and identify compounds enhancing thermoradiotherapy. This study also demonstrates the value of canine tumors to provide information generalizable to human tumors.
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Genómica/métodos , Imagen por Resonancia Magnética/métodos , Sarcoma/genética , Sarcoma/terapia , Animales , Análisis por Conglomerados , Terapia Combinada , Perros , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Hipertermia Inducida , Análisis de Secuencia por Matrices de Oligonucleótidos , Radioterapia/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
Combination chemotherapy is standard care for feline lymphoma, although clinically relevant improvements in remission duration are unlikely to result from manipulations of chemotherapy agents alone. Lymphopoietic tissues generally are sensitive to radiation, and support for chemoradiotherapy as a treatment for lymphoma is found in both humans and dogs. The goal of this prospective pilot study was to determine the normal tissue tolerance to 15 Gy total abdomen fractionated radiation therapy following induction chemotherapy in cats with lymphoblastic lymphoma. Eight cats with lymphoblastic gastrointestinal or multicentric lymphoma confined to the abdominal cavity were treated with a 6-week combination chemotherapy protocol followed 2 weeks later by whole-abdomen radiation therapy consisting of 10 daily fractions of 1.5 Gy. Treatment was well tolerated; renal insufficiency documented in one cat at the start of radiation therapy progressed to stable chronic renal failure. One cat not in complete remission at the time of radiation therapy relapsed 2 weeks later, one cat with multicentric lymphoma relapsed with hepatic large granular lymphoma, and one cat was euthanatized 3 weeks following completion of radiation therapy for other reasons; no evidence of lymphoma or radiation toxicoses was identified on post mortem evaluation. The remaining five cats remain in remission at least 266 days after starting therapy; median remission duration has not been reached (range, > 266 to > 1332 days). Results of this study suggest that 15 Gy total abdomen fractionated radiation therapy after induction chemotherapy is tolerated satisfactorily. This protocol is suitable for further testing to quantify efficacy.
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Neoplasias Abdominales/veterinaria , Enfermedades de los Gatos/radioterapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/veterinaria , Neoplasias Abdominales/sangre , Neoplasias Abdominales/tratamiento farmacológico , Neoplasias Abdominales/radioterapia , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedades de los Gatos/sangre , Enfermedades de los Gatos/tratamiento farmacológico , Gatos , Terapia Combinada/veterinaria , Proyectos Piloto , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Dosificación Radioterapéutica , Inducción de Remisión/métodos , Resultado del TratamientoRESUMEN
Lameness originating from the metacarpo(tarso)phalangeal (MP) joint has a significant effect on the use and athletic competitiveness of a horse. The identification of the cause of lameness originating from the MP joint can be challenging, given the limitations of radiography, ultrasonography, and nuclear scintigraphy. Our purpose was to describe the injury types and incidence in magnetic resonance imaging (MRI) studies from 40 horses with lameness attributable to the MP joint region where it was not possible to reach a clinically plausible diagnosis using other imaging modalities. Horses were examined in a 1.5 T magnet (Siemens Medical Solutions) under general anesthesia. The frequency of occurrence of MR lesions was subchondral bone injury (19), straight or oblique distal sesamoidean desmitis (13), articular cartilage injury and osteoarthritis (eight), suspensory branch desmitis (seven), osteochondral fragmentation (seven), proximal sesamoid bone injury (seven), inter-sesamoidean desmitis (four), deep digital flexor tendonitis (four), collateral desmitis (three), superficial digital flexor tendonitis (two), enostosis-like lesions of the proximal phalanx or MCIII (two), desmitis of the palmar annular ligament (one), desmitis of the proximal digital annular ligament (one), and dystrophic calcification of the lateral digital extensor tendon (one). Twenty-five horses had multiple MR abnormalities. MRI provided information that was complementary to radiography, ultrasonography, and nuclear scintigraphy and that allowed for a comprehensive evaluation of all structures in the MP joint region and a diagnosis in all 40 horses.
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Enfermedades de los Caballos/patología , Cojera Animal/patología , Imagen por Resonancia Magnética/veterinaria , Articulación Metacarpofalángica/patología , Tejido Adiposo/patología , Animales , Enfermedades Óseas/patología , Enfermedades Óseas/veterinaria , Calcinosis/patología , Calcinosis/veterinaria , Caballos , Imagen por Resonancia Magnética/métodos , Osteoartritis/patología , Osteoartritis/veterinaria , Huesos Sesamoideos/patologíaRESUMEN
The poor overall survival for patients with locally advanced breast cancers has led over the past decade to the introduction of numerous neoadjuvant combined therapy regimens to down-stage the disease before surgery. At the same time, more evidence suggests the need for treatment individualisation with a wide variety of new targets for cancer therapeutics and also multi modality therapies. In this context, early determination of whether the patient will fail to respond can enable the use of alternative therapies that can be more beneficial. The purpose of this review is to examine the potential role of magnetic resonance imaging (MRI) in early prediction of treatment response and prognosis of overall survival in locally advanced breast cancer patients enrolled on multi modality therapy trials that include hyperthermia. The material is organised with a review of dynamic contrast (DCE)-MRI and diffusion weighted (DW)-MRI for characterisation of phenomenological parameters of tumour physiology and their potential role in estimating therapy response. Most of the work published in this field has focused on responses to neoadjuvant chemotherapy regimens alone, so the emphasis will be there, however the available data that involves the addition of hyperthermia to the regimen will be discussed The review will also include future directions that include the potential use of MRI imaging techniques in establishing the role of hyperthermia alone in modifying breast tumour microenvironment, together with specific challenges related to performing such studies.
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Neoplasias de la Mama/terapia , Hipertermia Inducida , Imagen por Resonancia Magnética/métodos , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Terapia Combinada , Femenino , HumanosRESUMEN
Sonography is commonly used for diagnosis of desmopathy of the proximal part of the suspensory ligament in horses. However, magnetic resonance (MR) imaging has been stated to be superior for detecting disease and localizing lesions. In this retrospective study of 39 horses or 46 hind limbs with lameness due to proximal plantar metatarsal pain, the clinical and diagnostic findings are discussed and sonography and MR imaging compared for examination of the proximal part of the suspensory ligament. With MR imaging interpreted as the clinical gold standard, desmopathy of the proximal part of the suspensory ligament was diagnosed in 21 hind limbs, proximal plantar metatarsal pain of unknown cause in 12, an osseous injury at the origin of the suspensory ligament in four and a condition unrelated to the suspensory ligament in nine. Based on these findings, sonography had a sensitivity of 0.77 and 0.66 and specificity of 0.33 and 0.31 for diagnosing proximal suspensory desmopathy and for accurately localizing lesions, respectively. MR imaging changes consistent with proximal suspensory desmopathy were signal hyperintensities and an increase in cross-sectional area compared with the contralateral limb. Anesthesia of the deep branch of the lateral plantar nerve is not specific neither for proximal suspensory desmopathy, as conditions unrelated to the suspensory ligament were diagnosed, nor for diagnosis of proximal plantar metatarsal pain, as conditions outside the proximal plantar metatarsal region were also diagnosed.
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Enfermedades de los Caballos/diagnóstico , Cojera Animal/diagnóstico , Imagen por Resonancia Magnética/veterinaria , Huesos Metatarsianos/diagnóstico por imagen , Dolor/veterinaria , Análisis de Varianza , Animales , Femenino , Enfermedades de los Caballos/diagnóstico por imagen , Caballos , Cojera Animal/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/normas , Masculino , Dolor/diagnóstico , Dolor/diagnóstico por imagen , Radiografía , Estudios Retrospectivos , Sensibilidad y Especificidad , UltrasonografíaRESUMEN
An aged pony with extensive paranasal sinus and nasal passage B-cell lymphoma was treated with palliative radiation therapy. Sixteen gray were administered in two fractions, 7 days apart. A lateral field was used for the first fraction and a dorsal field for the second. Because of tumor being present in the left frontal sinus, gross tumor was knowingly excluded from the treated volume in the lateral field. The tumor regressed within 2 months and the pony remained free of clinical disease for 2.5 years. Acute, temporary blindness developed shortly after the second radiation fraction, but a direct causal relationship with the radiation therapy was not confirmed. The only radiation side effect was leukotrichia. Palliative treatment was successful in improving and prolonging the quality of life. These results suggest that localized equine B-cell lymphoma is radiosensitive, and that palliative radiation therapy is a reasonable consideration for large tumors, even when tumor volume prevents all gross tumor from being irradiated.
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Enfermedades de los Caballos/radioterapia , Linfoma de Células B/veterinaria , Neoplasias de los Senos Paranasales/veterinaria , Animales , Eutanasia Animal , Enfermedades de los Caballos/patología , Caballos , Linfoma de Células B/patología , Linfoma de Células B/radioterapia , Masculino , Cuidados Paliativos/métodos , Neoplasias de los Senos Paranasales/radioterapia , Dosis de Radiación , Resultado del TratamientoRESUMEN
The purpose of this review is to examine the roles that functional imaging may play in prediction of treatment response and determination of overall prognosis in patients who are enrolled in thermotherapy trials, either in combination with radiotherapy, chemotherapy or both. Most of the historical work that has been done in this field has focused on magnetic resonance imaging/magnetic resonance spectroscopy (MRI/MRS) methods, so the emphasis will be there, although some discussion of the role that positron emission tomography (PET) might play will also be examined. New optical technologies also hold promise for obtaining low cost, yet valuable physiological data from optically accessible sites. The review is organised by traditional outcome parameters: local response, local control and progression-free or overall survival. Included in the review is a discussion of future directions for this type of translational work.
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Hipertermia Inducida , Microcirculación , Neoplasias/terapia , Termografía/métodos , Terapia Combinada , Supervivencia sin Enfermedad , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Neoplasias/irrigación sanguínea , Neoplasias/tratamiento farmacológico , Tomografía de Emisión de Positrones , Valor Predictivo de las Pruebas , Curva ROCRESUMEN
Despite the availability of commercial tissue equivalent bolus material, wet gauze has an application in radiation therapy to provide superior conformance to irregular contours. Wet gauze bolus has the potential to reduce air gaps between the bolus and surface, which could decrease surface dose if sufficiently large to disrupt electronic equilibrium. Wet gauze bolus is often fabricated and wetness judged qualitatively. We assessed the effect of specific gauze wetness levels, quantified in terms of physical density, at various field sizes with respect to their effectiveness as bolus material compared with Superflab. For large fields, > 7 x 7 cm2 in this study, wet gauze sponges with a physical density of 1.02 g/cm3 performed essentially identical to Superflab; at a smaller field size the wet gauze was slightly less effective, likely due to the heterogeneity of the gauze-water matrix. Gauze that was wetter, with a physical density of 1.2 g/cm3, or less wet, with a physical density of 0.75 g/cm3 was not as effective either due to enhanced photon absorption in the wetter sponges, or less effective establishment of electronic equilibrium in the less wet sponges. The presence of an air gap under Superflab led to reduced surface dose, especially for small fields and large air gaps. Thus, if Superflab use leads to poor contact with the skin, wet gauze having a physical density of 1.02 g/cm3 can be used as a substitute. Judging the water content of wet gauze subjectively is not acceptable as over- or under wetness can lead to decreased effectiveness of the bolus material.
Asunto(s)
Dosis de Radiación , Radioterapia de Alta Energía/veterinaria , Piel/efectos de la radiación , Tapones Quirúrgicos de Gaza , Animales , AguaRESUMEN
PURPOSE: This study tests whether dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters obtained from canine patients with soft tissue sarcomas, treated with hyperthermia and radiotherapy, are predictive of therapeutic outcome. EXPERIMENTAL DESIGN: Thirty-seven dogs with soft tissue sarcomas had DCE-MRI done before and following the first hyperthermia. Signal enhancement for tumor and reference muscle were fitted empirically, yielding a washin/washout rate for the contrast agent and tumor area under the signal enhancement curve (AUC) calculated from 0 to 60 seconds, 90 seconds, and the time of maximal enhancement in the reference muscle. These parameters were then compared with local tumor control, metastasis-free survival, and overall survival. RESULTS: Pretherapy rate of contrast agent washout was positively predictive of improved overall and metastasis-free survival with hazard ratio of 0.67 (P = 0.015) and 0.68 (P = 0.012), respectively. After the first hyperthermia washin rate, AUC60, AUC90, and AUCt-max were predictive of improved overall and metastasis-free survival with hazard ratio ranging from 0.46 to 0.53 (P < 0.002) and 0.44 to 0.55 (P < 0.004), respectively. DCE-MRI parameters were compared with extracellular pH and (31)P MR spectroscopy results (previously published) in the same patients showing a correlation. This suggested that an increase in perfusion after therapy was effective in eliminating excess acid from the tumor. CONCLUSIONS: This study shows that DCE-MRI has utility predicting overall and metastasis-free survival in canine patients with soft tissue sarcomas. To our knowledge, this is the first time that DCE-MRI parameters are predictive of clinical outcome for soft tissue sarcomas.