A medical lumen-expansion balloon may include a generally cylindrical central body between first and second body end portions, a low-profile unexpanded first state and a radially-expanded second state, wherein the first body end portion is constrained by fiber material such that it will not expand longitudinally and circumferentially beyond a predetermined size, and the central body is constrained by fiber material so as to be circumferentially substantially noncompliant, but is longitudinally compliant, such that it will elongate with increased volume but will not substantially radially expand.