Access needles and stylet assemblies

An access needle comprising:

• an elongate hollow cannula having a proximal end, a distal end, and a lumen extending therebetween;
• and
• a stylet removably disposed within the lumen of the cannula, the stylet comprising:
• a hollow piercing tip disposed at a distal end of the stylet;
• and
• a flexible body length comprising a plurality of wire strands, said wire strands contacting each other and being oriented both generally parallel with each other and with a central longitudinal axis of the stylet extending proximally from the piercing tip toward the proximal end, whereby an outer boundary of the flexible body of the stylet is sized to an inner diameter of the lumen of the cannula but the flexible body occupies less than an entire cross-sectional volume of the lumen and thereby provides a path of fluid communication through the entire lumen of the cannula such that a contrast fluid can effectively pass through the lumen of the cannula in contact with the cannula lumen, longitudinally between and around wire strands of the stylet, and through an inside of the hollow piercing tip while the stylet is disposed within the lumen of the cannula and contacts an inward-facing surface of the cannula that defines the lumen of the cannula between the proximal end and the distal end of the cannula.