Abstract: A cavity (3) such as the urethra of a patient is lined by providing a lining device that comprises an eversible chamber (12) and a liner (16) connected thereto. Fluid pressure is applied to the chamber (12) to cause the chamber (12) to evert and advance into the cavity (3) such that the chamber (12) carries the liner (16) into the cavity. A vacuum is then applied to the chamber (12) to cause it to deflate. A part, such as a catheter or cable, can then be inserted into the cavity through the liner (16). If the cavity is the urethra of a patient, the liner shields the catheter from the distal part (1) of the urethra which is colonised with bacteria, and therefore reduces the risk of a urinary tract infection.

Abstract: A body cavity lining means is disclosed having a fluid chamber (9) and at least one further means (23) for providing liner means rigidity, in use. Means (23) comprises a further fluid chamber. The provision of two fluid chambers provides much greater control over the insertion and removal of the lining means. The provision of two separate fluid chambers allows the rigidity of the chambers to be controlled independently of eversion. In one embodiment the lining means is used to assist in the insertion of an endoscope for performing a colonoscopy. In one embodiment the at least one further means for providing liner means rigidity comprises a resiliently deformable extendible elongate member. In another embodiment one of the two fluid chambers is formed partially by the endoscope or other semirigid member, and means is provided for advancing the endoscope within the colon.