Why carry out this study?

GLOA (ganglionic local opioid analgesia) at the SCG (superior cervical ganglion) is performed for pain control and is known to be a safe and effective procedure with low complication rates

This procedure has, however, very variable effects on post-interventional pain scores, possibly due to different patterns of fluid spread in anatomic regions leading to these inconsistent post-interventional pain outcomes

The primary objective of the present study was to evaluate the spread of the injected substance in the area of the SCG immediately after GLOA

We also expected a correlation between the area and volume of the injectate spread and documented post-procedural pain scores and other clinical outcome measures

What was learned from the study?

To the best of our knowledge, this is the first published magnetic resonance imaging analysis focused on fluid spread in the area of the SCG immediately after GLOA

Clinicians should be aware of a laterodorsal needle direction to prevent possible block failures

A total volume of 2 ml injected into the parapharyngeal space and its “medial compartment” is recommended to reach the SCG. Higher volumes may lead to uncontrolled distribution patterns. especially when the stylopharyngeal fascia is absent