RESUMEN
BACKGROUND AND PURPOSE: Fast spin-echo short τ inversion recovery sequences have been very useful for MR imaging-guided deep brain stimulation procedures in Parkinson disease. However, high-quality fast spin-echo imaging deposits significant heat, exceeding FDA-approved limits when patients already have undergone deep brain stimulation and need a second one or a routine brain MR imaging for neurologic indications. We have developed a STIR sequence with an ultra-low specific absorption rate that meets hardware limitations and produces adequate tissue contrast in cortical and subcortical brain tissues for deep brain stimulation recipients. MATERIALS AND METHODS: Thirteen patients with medically refractory Parkinson disease who qualified for deep brain stimulation were imaged at 1.5T with a fast spin-echo short τ inversion recovery sequence modified to meet conditional MR imaging hardware and specific absorption rate restrictions. Tissue contrast-to-noise ratios and implant localization were objectively and subjectively compared by 2 neuroradiologists, and image quality for surgical planning was assessed by a neurosurgeon for high and low specific absorption rate images. RESULTS: The mean contrast-to-noise ratio for cerebral tissues without including the contrast-to-noise ratio for ventricular fluid was 35 and 31 for high and low specific absorption rate images. Subjective ratings for low specific absorption rate tissue contrast in 77% of patients were identical to (and in a few cases higher than) those of high specific absorption rate contrast, while the neurosurgical coordinates for fusing the stereotactic atlas with low specific absorption rate MR imaging were equivalent to those of the high specific absorption rate for 69% of patients. CONCLUSIONS: Patients with Parkinson disease who have already had a deep brain stimulation face a risk of neural injury if routine, high specific absorption rate MR imaging is performed. Our modified fast spin-echo short τ inversion recovery sequence conforms to very conservative radiofrequency safety limits, while it maintains high tissue contrast for presurgical planning, postsurgical assessment, and radiologic evaluations with greater confidence for radiofrequency safety.
Asunto(s)
Lesiones Encefálicas/etiología , Estimulación Encefálica Profunda/efectos adversos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/efectos adversos , Enfermedad de Parkinson/patología , Traumatismos por Radiación/etiología , Protección Radiológica/métodos , Anciano , Lesiones Encefálicas/patología , Lesiones Encefálicas/prevención & control , Estimulación Encefálica Profunda/instrumentación , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/terapia , Dosis de Radiación , Traumatismos por Radiación/patología , Traumatismos por Radiación/prevención & control , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
The joint care of children with obstructive uropathy by perinatologists, pediatric intensivists, pediatric nephrologists and urologists can preserve as much renal function as possible. Complications such as urinary tract infections and problems with renal insufficiency can be prevented. Preterm delivery for early surgical decompression of the urinary tract postpartal should be performed only in exceptional cases. We want to underline that supporting and counselling parents in coping with severe findings and prognosis of the disease is among our main aims. We will present two selected cases to demonstrate the spectrum of methods for handling fetal obstructive uropathy.
Asunto(s)
Enfermedades Fetales/terapia , Hidronefrosis/congénito , Grupo de Atención al Paciente , Obstrucción Uretral/congénito , Femenino , Edad Gestacional , Humanos , Hidronefrosis/terapia , Recién Nacido , Fallo Renal Crónico/congénito , Fallo Renal Crónico/terapia , Pruebas de Función Renal , Masculino , Enfermedades Renales Poliquísticas/congénito , Enfermedades Renales Poliquísticas/terapia , Embarazo , Diagnóstico Prenatal , Obstrucción Uretral/terapiaRESUMEN
Previous fecal collection cups with tape fixation frequently led to serious necroses of the rat tail due to strangulations, and did not allow for growth of the tail. A recently developed new model gives space for rapidly growing tails and is securely fixed by a cannula perforating both fecal collection cup and tail. It is transparent, cheap to be made, and easy to empty and was tested in 118 animals for two and four weeks. In no case the cup did loosen or had to be removed due to infections, strangulations or any local problems.
Asunto(s)
Coprofagia/prevención & control , Heces , Manejo de Especímenes/veterinaria , Cola (estructura animal)/crecimiento & desarrollo , Animales , Masculino , Ratas , Ratas Endogámicas , Organismos Libres de Patógenos Específicos , Cola (estructura animal)/patologíaRESUMEN
36 rat esophagi were irradiated by argon laser via an applicator with circumferential light distribution. They were perfused with glutaraldehyde and studied by light and transmission electron microscopy immediately, 2 days and 14 days after irradiation. Immediately after irradiation the laser center showed destruction of the keratinized stratified squamous epithelium. The collagenous fibers of the connective tissue were altered; fibrocytes and fibroblasts were severely damaged, and the microvascular lumina were occluded. The smooth muscle tissue and skeletal muscle tissue showed myofilament defects and initial karyonecrosis. There was decreasing damage of both fiber types up to 4 mm from the laser center. After 2 days the morphology of the laser center was not different from that seen immediately after irradiation. At a distance of 2 mm a partly differentiated new epithelium emerged below the necrotic epithelium. An inflammatory reaction was found in the connective tissue. After 14 days the esophageal wall was replaced and the lumen was occluded by young granulation tissue in the former laser center. Peripherally the esophageal wall appeared almost normal. As the rat esophagus serves as a model for esophagotracheal fistulae in newborn children, our findings indicate that the argon laser should be capable of occluding these fistulae likewise.