Fluoroscopy-Guided Blockade of the Greater Occipital Nerve in Cadavers: A Comparison of Spread and Nerve Involvement for Different Injectate Volumes

Figure 2

The images of the injectate distribution. (a) Test cadaver post left-sided injection with 2 ml of injectate. The dissection revealed coating of the second cervical nerve root. (b) Test cadaver post left-sided injection with 5 ml of injectate. Dissection revealed coating of the mastoid tip of sternocleidomastoid. (c) Test cadaver post left-sided injection with 2 ml of injectate. The dissection revealed coating of GON without coating of TON. (d) Test cadaver post right-sided injection with 3.5 ml of injectate. The dissection revealed coating of both GON and TON. (e) Test cadaver post right-sided injection with 5 ml of injectate. The dissection revealed coating of both GON and TON. GON: greater occipital nerve; TON: third occipital nerve; LON: lesser occipital nerve; GAN: great auricular nerve; OCI: obliquus capitis inferior; OCS: obliquus capitis superior; RCM: rectus capitis major; SSC: semispinalis capitis; SCM: sternocleidomastoid; SpCap: splenius capitis; Trap: trapezius; TP: transverse process; SP: spinous process.

(a)

(b)

(c)

(d)

(e)