the present disclosure will now describe in detail embodiments of a surgical access port with reference to the drawings in which like reference numerals designate identical or substantially similar parts in each view . throughout the description , the term “ proximal ” will refer to the portion of the assembly closest to the operator , whereas the term “ distal ” will refer to the portion of the assembly farthest from the operator . although discussed in terms of an incision for a minimally invasive procedure , the presently disclosed surgical access port may be used in any naturally occurring orifice ( e . g . mouth , anus , or vagina ). referring initially to fig1 , a surgical access port 100 is shown . the surgical access port 100 includes a cylindrical member 110 having a generally hourglass shape , a proximal end 140 a and a distal end 140 b , and defining a longitudinal axis a 1 . the proximal end 140 a and the distal end 140 b are substantially perpendicular to the longitudinal axis a 1 and are each surrounded by an outer rim 150 a and 150 b , respectively . extending through the cylindrical member 110 along the longitudinal axis a 1 is at least one lumen 120 , and in embodiments , a plurality of lumens 120 . an example of an access port is disclosed in u . s . patent application publication no . 2010 / 0240960 a1 , the entire disclosure of which is incorporated by reference herein . also within the cylindrical member 110 , separate from the lumens 120 , is an internal inflation cavity 130 . the internal inflation cavity 130 may be symmetrical and centrally disposed as shown here , but in embodiments , may be of shape , plurality , and placement so as to maximize its effect on the surrounding lumens 120 . in embodiments , internal inflation cavity 130 may be of a generally “ x ” shape , with rounded edges . the internal inflation cavity 130 extends from some distance along the longitudinal axis a 1 from the proximal end 140 a of the cylindrical member 110 , and terminates at some distance along the longitudinal axis a 1 before the distal end 140 b of the cylindrical member 110 . coupled to the internal inflation cavity 130 is an inflation coupling 160 , which may be in the form of a tube or a port configured to be attached to the source of inflation fluid 170 . the inflation coupling 160 is coupled on its distal end to the internal inflation cavity 130 , and on its proximal end to a source of inflation fluid 170 . the internal inflation cavity 130 will be capable of retaining the inflation fluid . to this end , the internal inflation cavity 130 or the inflation coupling 160 may incorporate a structure to control the flow of inflation fluid to the internal inflation cavity . this structure may be a ball valve or other suitable flow control . additionally , the inflation coupling 160 may contain a structure to contribute to maintaining a substantially fluid - tight seal with the surgical access port 100 . such structure may be a press - fit member , bayonet - type , or threaded configuration . the source of inflation fluid 170 may be any source capable of supplying the inflation fluid to the internal inflation cavity 160 . such a capable source may be a syringe , pump , or reservoir . the source of inflation fluid 170 will supply inflation fluid that is biocompatible and suitable for surgical procedures , such as co 2 , air , or saline . in embodiments , a surgical access port 100 may also include a port for the communication of insufflation fluid to an internal body cavity 220 ( see fig4 ). alternatively , one of the lumens 120 may communicate the insufflation fluid to the internal body cavity 220 . turning to fig2 , the surgical access port 100 is shown in cross section along section line 2 - 2 . in this view , each of the lumens 120 can be seen disposed radially about the internal inflation cavity 130 . the lumens 120 are placed such that an expansion of the inflation cavity 130 will cause a shifting in the relative placement of the lumens 120 . such a shifting may allow greater dexterity and range in performing a surgical procedure with instruments 210 ( see fig3 ) disposed within the lumens 120 . when the inflation cavity 130 is not inflated , as shown here , a first state is defined . in a first state , the inflation cavity 130 has an internal pressure that is essentially equalized with that of the surrounding environment . a first state diameter d 1 is associated with the first state , measured transverse to the longitudinal axis a 1 . referring to fig3 , the surgical access port 100 is shown in top perspective view inserted into tissue 180 through an incision site 190 . the proximal end 140 a of the cylindrical member 110 can be seen extending through the surface of the tissue 180 . in this arrangement , surgical instruments 210 can be inserted into lumens 120 , and can be seen extending therethrough as shown in phantom view . also shown in phantom view is the internal inflation cavity 130 . extending through the top of the proximal end 140 a of cylindrical member 110 is inflation coupling 160 . thus , the surgical access port 100 in fig3 is shown in a first , unexpanded , state . turning to fig4 , a side view of the surgical access port of 100 is shown . in this view , the surgical instruments 210 can be seen extending completely through the lumens 120 ( shown in phantom view ). also shown is a relative spacing measurement x 1 , measured transverse to the longitudinal axis a 1 between the centers of lumens 120 , while the surgical access port 100 is in a first , unexpanded , state . in use , the operator of the surgical access port 100 will first place the surgical access port 100 in an incision site 190 such that the surgical access port is disposed within a layer of tissue 180 , as shown in fig3 . the operator of the surgical access port 100 will then couple the inflation coupling 160 to the source of inflation fluid 170 , allowing the internal inflation cavity 130 to expand when fluid is introduced to the internal inflation cavity 130 . the source of inflation fluid 170 supplies pressurized fluid to expand the internal inflation cavity 130 . this may be accomplished by pumps or reservoirs , or any other suitable pressure - generating apparatus . the operator of the surgical access port 100 will allow the internal inflation cavity 130 to expand such that the walls of the cylindrical member 110 expand to fill the space between the cylindrical member 110 and the walls of the incision site 190 , until a substantially fluid - tight seal is formed between the walls of the cylindrical member 110 and the walls of the incision site 190 . the surgical access port 100 is then ready for surgical instruments and tools 210 to be inserted therethrough for use in minimally invasive surgical procedures . referring now to fig5 , a cross - sectional view along the line 2 - 2 as shown in fig2 is shown , now with the surgical access port 100 in an expanded , second state . here , the second state diameter d 2 is shown , clearly different than first state diameter d 1 . it is also shown that internal inflation cavity 130 has expanded and cylindrical member 110 has expanded in response . turning to fig6 , the surgical access port 100 is in an expanded second state . the relative spacing measurement x 2 , measured transverse to the longitudinal axis between the centers of lumens 120 ( shown in phantom view ) is clearly different than the relative spacing measurement of the first state , x 1 . as a result , the lumens 120 enjoy greater relative spacing and greater freedom of movement . this greater spacing may also provide access to point in an internal body cavity 220 that may have been accessible by the surgical instruments 210 while the surgical access port 100 was in the first state . additionally , the forces exerted by the expanded surgical access port 100 may also serve to retract tissue outward from an incision site 190 . further , the compressible nature of the cylindrical member 110 may cause the lumens 120 to form a tighter seal about surgical instruments 210 disposed therethrough in the second state . in order to remove the device , the operator of the surgical access port 100 will uncouple the source of inflation fluid 170 from the inflation coupling 160 . surgical instruments and tools 210 will then be removed from the lumens 120 , and inflation fluid will be released from the internal inflation cavity 130 . this latter step may include opening a plug , seal , or other port in order to release pressurized inflation fluid . the surgical access port 100 will then transition from a second state to a first state , with a corresponding decrease in diameter , measured transverse to the longitudinal axis a 1 . the surgical access port can then be easily removed from an incision site 180 . referring to fig7 , a surgical access port 200 is shown in a first state , with four lumens 120 spaced evenly about the longitudinal axis a 1 , as well as four separate inflation cavities 230 , shown here evenly spaced about the longitudinal axis a 1 . separate internal inflation cavities 230 may function to maximize spacing between lumens 120 upon transition of the surgical access port 200 from a first state to a second state . it is additionally contemplated that the surgical access port may be coated with any number of medicating substances or materials to facilitate healing , or to make the use of the surgical access port during surgery more effective . it will be understood that various modifications may be made to the embodiments disclosed herein . therefore , the above description should not be construed as limiting , but merely as exemplifications of embodiments . those skilled in the art will envision other modifications within the scope and spirit of the present disclosure . what d
a surgical access port that includes a cylindrical member having a proximal end and a distal end and defining a longitudinal axis ; at least two lumen extending through the cylindrical member along the longitudinal axis ; at least one cavity defined in the cylindrical member and positioned radially within the at least two lumen ; and a source of inflation fluid coupled to the at least one cavity , the source of inflation configured to permit selectable inflation of the at least one cavity , whereby inflation of the at least one cavity increases the radial distance between the at least two lumen .