Sphenopalatine Block Versus Greater Occipital Nerve Block in PDPH

Management of postdural puncture headache (PDPH) has always been challenging for anesthesiologists. PDPH not only increases the misery of the patient, but the length of stay and overall cost of treatment in the hospital also increases. Although the epidural blood patch ( EBP ) is an effective way of treating the problem, the procedure itself could cause another inadvertent dural puncture (DP). Moreover, sometimes patients need to have a second EBP, if the first one is not completely effective. This can be difficult to explain to the patient who has already suffered a lot. Peripheral nerve blocks are well tolerated and effective as adjunctive therapy for many disabling headache disorder. Sphenopalatine ganglion is a parasympathetic ganglion, located in the pterygopalatine fossa. Transnasal sphenopalatine ganglion block ( SPGB ) has been successfully used to treat chronic conditions such as migraine, cluster headache, and trigeminal neuralgia, and may be a safer alternative to treat PDPH: It is minimally invasive and carried out at the bedside without using imaging. Besides that, it has apparently a faster start than EBP, with better safety profile. Another minimally invasive peripheral nerve block which has been used quite successful is greater occipital nerve block (GONB). The GONB has been in use for more than a decade to treat complex headache syndromes of varying etiologies like migraine , cluster headache and chronic daily headache with encouraging results. Greater Occipital Nerve (GON) arises from C2-3 segments, its most proximal part lies between obliqua capitis inferior and semispinalis, near the spinous process. Then, GON enters into semispinalis passing through it and after its exit; it enters into trapezius muscle. In distal region of trapezius fascia, it is crossed by the occipital artery and finally the nerve exits the trapezius fascia insertion into the nuchal line about 5-cm lateral to midline. Functionally, GON supplies major rectus capitis posterior muscle, and the skin, muscles, and vessels of the scalp, but is the main sensory supply of occipital region. Many providers believe that the local anesthetic produces the rapid onset of headache relief, like an abortive agent, and that the locally acting steroid produces the preventive like action of up to 6 weeks as dexamethasone possess potent anti inflammatory and immunosuppressive actions by inhibiting cytokine-mediated pathways .