Ultrasound-guided maxillary nerve block via the pterygopalatine fossa: anterior versus posterior infrazygomatic approach

Reply to Dr Alfaro-de la Torreet al

“…Alfaro-de la Torre et al demonstrated successful injection of dye into the PPF by using the posterior infrazygomatic approach 1. Such a finding was not replicated in our study, which we agree that it was possibly because we have adopted the technique previously described by Nader et al in which the LPP could not be completely visualized resulting in an inadequate spread of the injectate into the PPF 3 4.…”

“…We thank Dr Alfaro-de la Torre et al 1 for their interest and acknowledge their valuable contribution to our article 2. Certainly, in addition to the maxillary tuberosity (MT) and lateral pterygoid plate (LPP), the coronoid process is an interfering structure for ultrasound-guided maxillary nerve block using the LPP approach via the pterygopalatine fossa (PPF).…”

Ensuring the effectiveness and safety of peripheral blockades

“…Постановка ультразвукового датчика ниже скулового отростка височной кости непосредственно перед мыщелком нижней челюсти обычно позволяет идентифицировать лицевой нерв, поперечную лицевую артерию, верхнечелюстную артерию. Слабыми сторонами этого подхода считаются прохождение иглы в непосредственной близости с лицевым нервом, околоушной железой и необходимость открытия рта для уменьшения тени венечного отростка, что не всегда удобно при выполнении блокады интраоперационно во время наркоза и при ограничениях движения в височно-нижнечелюстном суставе [22,26].…”

Anatomical correctness

“…The greater wing of the sphenoid can easily be imaged with the transducer in the suprazygomatic area but not from the infrazygomatic area. When doing this, the lateral pterygoid plate of the sphenoid bone can be seen in the far field as a linear horizontal hyperechoic structure 4 with the infrazygomatic approach.…”