Supraorbital & Trochlear Nerve Blocks
Clinical uses: surgery on the forehead; supplement to superior aspect of the nose
Technique: Just as when doing the infraorbital block, it is prudent to always use the non-dominant hand to palpate the orbital rim to ensure that the needle tip is exterior to the bony orbital margin.
Supraorbital nerve:
The supraorbital nerve is the 1st division of CN V as it exits the supraorbital foramen. It supplies the forehead and area anterior to the coronal suture. This supraorbital notch is readily palpable in most patients.
After sterile preparation, a 25g needle is advanced subcutaneously in the midpupillary line in the eyebrow. Advance the needle tip until touching bone, then withdraw the needle a tiny amount. After (-) aspiration, inject 0.5- 1mL of LA.
Trochlear nerve:
The trochlear nerve divides into supratrochlear and infratrocheal branches supplying the forehead and nose, respectively. As an adjunct for scalp blocks or nasal surgery, this block is easily performed. After sterile preparation, a 25g needle is advanced subcutaneously at the medial border of the eyebrow. After (-) aspiration, inject 0.5-1mL of LA.
Uejima, T. and Suresh, S., 2008. Ommaya and McComb reservoir placement in infants: can this be done with regional anesthesia?. Pediatric Anesthesia, 18(9), pp.909-911.