Medical probes and methods of use

Abstract

A medical probe for guided insertion into soft tissue, such as the brain, is disclosed. The medical probe may include a flexible, elongated body having a proximal end portion and an opposed distal end portion. The elongated body has a length of at least 1 cm and an outer diameter of 80 μm or less. The distal end portion may comprise a beveled tip such that the distal end portion of the medical probe can be steered independently to a target site in the soft tissue.

We claim: 
     
         1 . A medical probe for insertion into soft tissue, the medical probe comprising:
 a flexible, elongated body having a proximal end portion and an opposed distal end portion,   wherein the elongated body has a length of at least 1 cm and an outer diameter of 80 μm or less, and   wherein the distal end portion comprises a beveled tip such that the distal end portion of the medical probe can be steered independently to a target site in the soft tissue.   
     
     
         2 . The medical probe of  claim 1 , wherein the elongated body is a microcapillary. 
     
     
         3 . The medical probe of  claim 1 , wherein the elongated body is formed of a biocompatible glass or biocompatible metal. 
     
     
         4 . The medical probe of  claim 1 , wherein the beveled tip has a bevel angle between about 15 degrees and 85 degrees. 
     
     
         5 . The medical probe of  claim 1 , wherein the outer diameter of the elongated body is between 10 μm and 80 μm. 
     
     
         6 . The medical probe of  claim 1 , wherein the outer diameter of the elongated body is from about 60 μm to about 80 μm. 
     
     
         7 . The medical probe of  claim 1 , wherein:
 the outer diameter of the elongated body is between 20 and 80 μm,   the beveled tip has a bevel angle between about 30 degrees and 80 degrees,   the elongated body has a length from 1 cm to 20 cm, and   the elongated body has a proximal end portion and a distal end portion which comprises the beveled tip.   
     
     
         8 . The medical probe of  claim 7 , wherein at least 1 cm of the distal end portion including the beveled tip is unsupported. 
     
     
         9 . The medical probe of  claim 8 , wherein the elongated body is a metal or glass microcapillary. 
     
     
         10 . A kit of parts, comprising:
 two or more medical probes of  claim 1 ,   wherein the angle of the bevel of the beveled tip of at least one of the medical probes is different from the angle of the bevel of the beveled tip of at least a second of the medical probes.   
     
     
         11 . A system for guided insertion of a medical probe into soft tissue, comprising:
 at least one medical probe of  claim 1 ; and   an insertion system which is operable to steer the distal end portion of the at least one medical probe a traverse distance of at least 1 cm into the soft tissue without the use of a guide tube or shuttle.   
     
     
         12 . The system of  claim 11 , wherein the insertion system includes a motor, actuator, and controller configured to linearly displace and axially rotate the at least one medical probe. 
     
     
         13 . A method of inserting a medical probe into soft tissue, the method comprising:
 identifying a target site in the soft tissue;   providing the medical probe of  claim 1 ; and   independently steering the distal end portion of the medical probe into the soft tissue a distance to insert the beveled tip to reach the target site.   
     
     
         14 . The method of  claim 13 , wherein the steering comprises rotating the beveled tip about the longitudinal axis of the elongated bodying during insertion into the soft tissue. 
     
     
         15 . The method of  claim 13 , wherein at least 1 cm of a distal end portion of the medical probe including the beveled tip is unsupported during the steering. 
     
     
         16 . The method of  claim 13 , wherein at least 2 cm of a distal end portion of the medical probe including the beveled tip is unsupported during the steering. 
     
     
         17 . The method of  claim 13 , wherein the step of providing the medical probe comprise selecting the medical probe which has a bevel angle of the beveled tip predetermined to produce a radius of curvature of insertion trajectory desired to reach the target site from an initial insertion point. 
     
     
         18 . The method of  claim 13 , wherein the soft tissue is the brain of a patient in need of treatment and/or diagnosis. 
     
     
         19 . A method of treatment of a specific site in soft tissue in a patient, comprising:
 identifying a target site in the soft tissue;   providing the medical probe of  claim 1 ;   independently steering the distal end portion of the medical probe into the soft tissue a distance to insert the beveled tip to reach the target site; and   delivering a treatment substance or energy through the elongated body of the medical probe and out of the distal end portion to the target site in the soft tissue.   
     
     
         20 . The method of  claim 19 , wherein the step of identifying a target site in the soft tissue comprises imaging the soft tissue and identifying an initial insertion point and an insertion trajectory desired to reach the target site from the initial insertion point. 
     
     
         21 . The method of  claim 19 , wherein the soft tissue is the brain of the patient. 
     
     
         22 . The method of  claim 19 , wherein the step of identifying a target site in the soft tissue comprises imaging the soft tissue and identifying an initial insertion point and an insertion trajectory desired to reach the target site from the initial insertion point. 
     
     
         23 . The method of  claim 19 , wherein the medical probe is a microcapillary, the soft tissue is the brain, and a pharmaceutically active agent is delivered through a lumen of the microcapillary to the target site. 
     
     
         24 . A method of inserting a medical probe into soft tissue, the method comprising:
 identifying a target site in the soft tissue;   providing an elongated medical probe having an outer diameter between 10 and 80 μm and comprising a distal end portion having a beveled tip; and   independently steering the distal end portion of the medical probe into the soft tissue a distance of at least 1 cm to reach the target site.   
     
     
         25 . The method of  claim 24 , wherein the soft tissue is the brain of a patient in need of treatment and/or diagnosis. 
     
     
         26 . The method of  claim 24 , wherein the steering comprises rotating the beveled tip about a longitudinal axis of the medical probe during insertion into the soft tissue. 
     
     
         27 . The method of  claim 24 , wherein the step of providing the medical probe comprise selecting the medical probe which has a bevel angle of the beveled tip predetermined to produce a radius of curvature of insertion trajectory desired to reach the target site from an initial insertion point. 
     
     
         28 . A method of treatment of a specific site in soft tissue in a patient, comprising:
 identifying a target site in the soft tissue;   providing a medical probe comprising a distal end portion having a beveled tip, wherein providing the medical probe comprises selecting the medical probe which has a bevel angle of the beveled tip predetermined to produce a radius of curvature of insertion trajectory desired to reach the target site from an initial insertion point;   independently steering the distal end portion of the medical probe into the soft tissue a distance of at least 1 cm to reach the target site; and   delivering a treatment substance or energy through the medical probe and out of the distal end portion to the target site in the soft tissue.   
     
     
         29 . The method of  claim 28 , wherein the soft tissue is the brain of the patient. 
     
     
         30 . The method of  claim 28 , wherein the step of identifying a target site in the soft tissue comprises imaging the soft tissue and identifying the initial insertion point and the insertion trajectory desired to reach the target site from the initial insertion point. 
     
     
         31 . The method of  claim 28 , wherein the medical probe is a microcapillary, the soft tissue is the brain, and a pharmaceutically active agent is delivered through a lumen of the microcapillary to the target site. 
     
     
         32 . A method of diagnosis of a patient, comprising:
 identifying a target site in a soft tissue in the patient;   providing a medical probe comprising a distal end portion having a beveled tip, wherein providing the medical probe comprises selecting the medical probe which has a bevel angle of the beveled tip predetermined to produce a radius of curvature of insertion trajectory desired to reach the target site from an initial insertion point;   independently steering the distal end portion of the medical probe into the soft tissue a distance of at least 1 cm to reach the target site; and   withdrawing a fluid sample from the target site through a lumen in the medical probe and then analyzing the fluid sample.