The current invention presents an extensible and guidable apparatus and methods to evaluate tubular or cavitary structure. The apparatus has a power, control and display unit and a flexible tubular device having a proximal end and a distal end. A stretchable conduit and a plurality of extensible channels run longitudinally inside the flexible tubular device. The flexible tubular device comprises a non-extensible tubular shaft and a reversibly extensible tubular shaft, connected longitudinally in tandem. The reversibly extensible tubular shaft comprises a plurality of reversible extension segments and is controllably longitudinally extensible and bendable by changes in pressure and volume of a medium in said reversible extension segments. Said tubular device is directionally bendable at the distal end by selective negative changes in pressure in said distal end. Said tubular device obtains visual information of target area and material samples, and is capable of manipulation of the target area.
