A device for providing access to a surgical location within a patient is
provided. The device includes an elongate body and a sleeve. The elongate
body has an outer surface, an inner surface, and a distal portion. The
inner surface defines a passage that extends through the elongate body
along a longitudinal axis through which surgical instruments can be
inserted to the surgical location. The distal portion is capable of
having an expanded configuration when inserted within the patient. In the
expanded configuration, the cross-sectional area of the passage at a
first location is greater than the cross-sectional area of the passage at
a second location, wherein the first location is distal to the second
location. The sleeve is configured to be moved relative to the elongate
body along the longitudinal axis to increase or to decrease the length of
the passage along the longitudinal axis.