Greater and Lesser Occipital Nerve Blocks
The greater and lesser occipital nerves branch off the spinal cord from between the first and second cervical vertebrae. They supply sensation to the skin along the back of the scalp to the top of the head. They do not cross the midline.
When the occipital nerve becomes inflamed and/or irritated, the pain can be referred to the top of the head and even into the eye of the same side as the irritated nerve. This is known as occipital neuralgia. The pain from these nerves does not cross the midline to the other side of the head. These nerves may also contribute to migraine, tension-type, and cluster headaches. If palpation of these nerves replicates the pain in the back of the head and/or into the eye, occipital nerve blocks using local anesthesia can be used to try to reduce and/or eliminate the pain.
Pain relief from occipital nerve blocks may last a few days, a few weeks, or, hopefully, a few months. Both greater and lesser occipital nerve blocks are given if the pain is on one side. If the pain is on both sides, then all four blocks are given. This procedure can be repeated if the pain returns.
Greater Occipital Nerve Block
The target for the injection of a greater occipital nerve block is one-third off the midline on the line between the occipital protuberance and the mastoid process. The The red area is the region the is usually numbed with a greater occipital nerve block.
Lesser Occipital Nerve Block
The target for the injection of a lesser occipital nerve block is two-thirds off the midline on the line between the occipital protuberance and the mastoid process. The red area is the region the is usually numbed with a lesser occipital nerve block.
Greater and Lesser Occipital Nerve Block
When both the greater and lesser occipital nerve blocks are given, the whole back side of the head usually feels numb. The occipital nerve blocks can also decrease and/or eliminate eye pain on the same side that the blocks were given.