摘要:
A microwave surgical ablation probe having an arrangement of coolant channels in fluid communication with a cooling chamber disposed within the distal end of the probe is disclosed. A hypotube having one or more longitudinal ribs extending radially inward from an inner surface thereof is coaxially disposed around a coaxial feedline. The longitudinal ribs of the hypotube engage an outer sheath of the feedline to define a fluid inflow channel to deliver coolant to the cooling chamber, and a fluid outflow channel to receive fluid from the cooling chamber. The cooling chamber may be formed from porous ceramic or porous metallic material that provides structural support to the probe while permitting coolant to circulate therethrough. The probe includes dielectric and choke members that are adapted to control the microwave radiation pattern (e.g., ablation shape), and which may provide improved coupling of the probe to tissue.
摘要:
An optical mode noise averaging device including a multimode optical fiber and means for averaging a modal noise induced signal level variation of light propagating within the multimode optical fiber. The device may average modal noise induced signal level variations by cyclically varying an index of refraction of the multimode optical fiber over a select period of time, scrambling a light distribution within the multimode optical fiber, or both. The index of refraction of the multimode optical fiber may be cyclically varied by cyclically varying the temperature of the multimode optical fiber. Alternatively, the index for refraction may be varied or the light distribution within the multimode optical fiber may be scrambled by cyclically manipulating the multimode optical fiber.
摘要:
A photoconductive composition comprises a photoconductor and a sensitizer. The sensitizer has the formula ##STR1## wherein R represents alkyl; R1 represents H, alkyl or aryl; R2 represents the atoms required to complete a hetero or carboxyclic ring; A.sup.- represents an anion; and n represents the valency of the anion. The composition is sensitive to both laser light sources and tungsten light sources and is useful in electrophotographic reproduction.
摘要:
A method of performing an ablation procedure includes the initial step of supplying a fluid to a cooling chamber defined within an antenna assembly. The method also includes the steps of decreasing the temperature of the fluid to form a solid material and inserting the antenna assembly into tissue. The method also includes the step of supplying energy to the antenna assembly to treat tissue. Residual heat from the antenna assembly transitions the solid material back to the fluid. The method also includes the step of circulating the fluid within the antenna assembly to dissipate heat emanating from the antenna assembly.
摘要:
A microwave surgical ablation probe having an arrangement of coolant channels in fluid communication with a cooling chamber disposed within the distal end of the probe is disclosed. A hypotube having one or more longitudinal ribs extending radially inward from an inner surface thereof is coaxially disposed around a coaxial feedline. The longitudinal ribs of the hypotube engage an outer sheath of the feedline to define a fluid inflow channel to deliver coolant to the cooling chamber, and a fluid outflow channel to receive fluid from the cooling chamber. The cooling chamber may be formed from porous ceramic or porous metallic material that provides structural support to the probe while permitting coolant to circulate therethrough. The probe includes dielectric and choke members that are adapted to control the microwave radiation pattern (e.g., ablation shape), and which may provide improved coupling of the probe to tissue.
摘要:
A method of performing an ablation procedure includes the initial step of supplying a fluid to a cooling chamber defined within an antenna assembly. The method also includes the steps of decreasing the temperature of the fluid to form a solid material and inserting the antenna assembly into tissue. The method also includes the step of supplying energy to the antenna assembly to treat tissue. Residual heat from the antenna assembly transitions the solid material back to the fluid. The method also includes the step of circulating the fluid within the antenna assembly to dissipate heat emanating from the antenna assembly.