Lesion diameter measurement catheter and method

• US 6,010,511 A
• Filed: 02/18/1999
• Issued: 01/04/2000
• Est. Priority Date: 05/04/1995
• Status: Expired due to Fees

• Current Assignee: Richard T. Murphy
• Original Assignee: Richard T. Murphy
• Inventors: Murphy, Richard
• Primary Examiner(s): Buiz, Michael
• Assistant Examiner(s): Shai, Daphna
• Application Number:
  US09/252,164
• Time in Patent Office: 320 Days
• Field of Search: 606/191, 606/192, 606/102, 128/779, 128/798, 128/780, 128/673
• US Class Current: 606/108
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence
• CPC Class Codes: A61M 2025/1072 having balloons with two or more compartments
• CPC Class Codes: A61M 2025/1079 having radio-opaque markers in the region of the balloon
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00

Abstract

The invention provides methods and apparatus for determining cross-sectional dimensions of body lumens, such as the diameter of a blood vessel. According to one exemplary method, the diameter of a blood vessel is measured by first inflating a balloon catheter within the lumen until the balloon diameter matches the lumen diameter. Inflation may be at a very low pressure and be constrained by the lumen, or may alternatively be controlled by monitoring the flow within the lumen. The balloon includes at least one measurement element which indicates the expanded balloon cross-sectional area, circumference, or diameter. Optionally, the measurement element provides a fluoroscopic, radiographic, or ultrasound indication of the cross-sectional dimension. In alternative embodiments, such dimensions may be transmitted to the distal end of the catheter, or determined after deflation and removal of the catheter.

Claims

1. A method for measuring a cross-sectional dimension of a target location of a body lumen, the method comprising:

inserting a catheter into the body lumen, wherein the catheter includes a balloon;

aligning the balloon with the target location within the body lumen;

inflating the balloon within the body lumen so that a cross-section of the balloon substantially matches the cross-section of the body lumen; and

measuring a cross-sectional dimension of the balloon, wherein the cross-sectional dimension of the balloon corresponds to a cross-sectional dimension of the target location of the body lumen.

2. A method as claimed in claim 1, wherein the measuring step comprises removing the balloon and determining irreversible changes in the balloon, wherein the changes correspond to a maximum inflated cross-sectional dimension.

3. A method for measuring a cross-sectional dimension of a target location of a body lumen, the method comprising:

inserting a catheter into the body lumen, wherein the catheter includes a balloon having, when fully expanded, a smaller portion which is smaller than the body lumen and a larger portion which is larger than the body lumen;

aligning the balloon with the target location within the body lumen;

inflating the balloon at low pressure until the smaller portion is fully expanded and the larger portion is restrained by the body lumen; and

measuring a largest fully expanded diameter of the balloon.

4. A method as claimed in claim 3, wherein the balloon includes a plurality of elements having distinct images when a corresponding cross-section dimension of the balloon is fully expanded, and wherein the measuring step comprises fluoroscopically or ultrasonically imaging the inflated balloon within the lumen and determining which of the elements have distinct images.

5. A method for measuring a cross-sectional dimension of a target location of a body lumen, the method comprising:

inserting a catheter into the body lumen, wherein the catheter includes a balloon;

aligning the balloon with the target location within the body lumen;

inflating the balloon within the body lumen so that a cross-section of the balloon substantially matches the cross-section of the body lumen;

measuring a cross-sectional dimension of the balloon while the balloon remains within the body lumen, wherein the cross-sectional dimension of the balloon corresponds to a cross-sectional dimension of the target location of the body lumen.