Ultrasound imaging and occipital nerve stimulation
Abstract
Objectives:
Occipital nerve stimulation (ONS) is a peripheral nerve stimulation (PNS) technique that has been used with success in the management of intractable chronic daily headaches (CDHs) and occipital neuralgia (ON). The technique involves the placement of a stimulating surgical or percutaneous electrode over the occipital nerves within the subcutaneous tissues at the skull base. Until recently, procedures involving the occipital nerves were based on identifying bony or arterial landmarks with direct palpation or fluoroscopy. Although universally accepted as an imaging technique, fluoroscopy does not provide real-time imaging of the occipital nerves or vessels. Furthermore, therapeutic efficacy of ONS is directly related to the ability of the stimulating electrode to produce peripheral nerve dermatomal paresthesia, emphasizing the need for precision placement.
Materials and methods:
A total of six patients, diagnosed with refractory CDH and ON, after failing extensive medical management, were diagnosed as potential candidates for ONS. Subsequently, all underwent successful percutaneous trials of bilateral octopolar (Advanced Neuromodulation Systems, Plano, TX, USA) ONS under ultrasound guidance, followed by permanent surgical implantation.
Results:
In this case series, ultrasound provided accurate, real-time placement of introducer needles and stimulating electrodes by allowing visualization of tissue planes (epidermis, dermis, subcutaneous fat, and trapezious muscle), as well as vessels and nervous structures.