Abstract: A method and apparatus for treating a body tissue in situ (e.g., an atrial tissue of a heart to treat) atrial fibrillation include a lesion formation tool is positioned against the heart surface. The lesion formation tool includes a guide member having a tissue-opposing surface for placement against a heart surface. An ablation member is coupled to the guide member to move in a longitudinal path relative to the guide member. The ablation member has an ablation element for directing ablation energy in an emitting direction away from the tissue-opposing surface. The guide member may be flexible to adjust a shape of the guide member for the longitudinal path to approximate the desired ablation path while maintaining the tissue-opposing surface against the heart surface. In one embodiment, the ablation member includes at least one radiation-emitting member disposed to travel in the longitudinal pathway. Transmurality can be assessed to approximate a location of non-transmurality in a formed lesion.

Abstract: A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface.

Abstract: A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface.

Abstract: A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface.

Abstract: A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface.

Abstract: A method and apparatus for treating in situ biologic tissue include identifying a patient with a condition susceptible to treatment by forming a lesion in the tissue and accessing a surface of the tissue. A lesion formation tool is positioned against the accessed surface. The tool includes an optical fiber for guiding a coherent waveform of a selected wavelength to a fiber tip for discharge of light energy from the fiber tip. The wavelength is selected for the light energy to penetrate a full thickness of the tissue to form a volume of necrosed tissue through the thickness of the tissue. The tool further includes a guide tip coupled to the fiber tip. The guide tip is adapted to have a discharge bore aligned with the fiber tip to define an unobstructed light pathway from the fiber tip to the tissue surface.