PMC

Projectile delivery systems; a, compressed air gun with 6 mm barrel situated in front of a clamped specimen (arrow); b, 21.3 mm calibre gas gun chamber with high-speed camera located on a tripod at the viewing window; the 21.3 mm barrel enters the chamber at left (arrow); c, view inside the 21.3 mm gas gun chamber showing specimen clamped in front of the barrel (arrow); part of the viewing window is illuminated at left; inset shows a 6 mm projectile housed in a plastic sabot; d, image of Enfield number three proof housing with barrel located at left (arrow)

Helios gene gun. (a) The gene gun is loaded and ready for discharge. Here, it is displayed with the original accelerator chamber and associated spacer (inset). The spacer defines the minimum distance between the target and the accelerator channel cone. The cone is designed to spread the gold/DNA particles superficially over a wide area. (b) The gene gun with the modified chamber. The spacer has been eliminated, and the cone-shaped barrel is replaced with an external barrel with a reduced diameter (inset). This reduces the spread of microcarriers over the target site and allows the apparatus to be placed closer to tissue targets.

7 years old female with ectopic anus and barrel gun perineum. MRI of the pelvis, STIR sequence in axial plane showing three separate tracts: urinary (green outline), vaginal (yellow outline) and bowel (orange outline). No fistulous communication. (Protocol: 0.35T, TR 7330ms, TE 126ms, slice thickness 3mm, interslice gap 1.8mm)

7 years old female with ectopic anus and barrel gun perineum. MRI of the pelvis, STIR sequence in sagittal plane after instillation of 20cc of ultrasound gel shows gel to be located in the rectum (orange outline) and endometrial cavity(yellow outline). The fat plane between the uterus and rectum is well-maintained. There is no fistulous communication.(Barrel gun perineum). Urethra (green outline) and bladder (star) are normal. (Protocol: 0.35T, TR 7330ms, TE 126ms, slice thickness 3mm, interslice gap 1.8mm)