Figure 1. (A) Ultrasound depiction during internal jugular vein puncture, illustrating the observation encountered during guide wire insertion. The longitudinal ultrasound image reveals that after the guide wire penetrated the outer membrane of the internal jugular vein, a section of the wire wrapped around the blood vessel wall. The long white arrow denotes the central venous puncture guide wire. S – superior; I – inferior. (B) Representation of ultrasound conducted when insertion after guide wire removal proved challenging. The image displays a “pseudolumen” (indicated by the white dashed line) situated between the outer and inner-middle membrane of the internal jugular vein, with discernible fluid-filled dark areas within. IJV – internal jugular vein; SCM – sternocleidomastoid muscle. White dashed line represents the “pseudolumen” formed in the blood vessel wall after removing the guide wire. S – superior; I – inferior. (C) Ultrasound-guided intraplane jugular venocentesis catheter placement. IJV – internal jugular vein; SCM – sternocleidomastoid muscle. White arrowheads indicate vascular intimal calcification; the long white arrow represents the central vein puncture needle.