Willingness to accept and pay for implantable tinnitus treatments: a survey.

OBJECTIVES: At present, there is no cure for tinnitus. Neurostimulation techniques have shown great promise, but it is uncertain whether they will gain acceptance because of their invasive nature. We have previously demonstrated that pairing acoustic stimuli with vagus nerve stimulation (VNS) also has potential as a viable tinnitus treatment approach. METHODS: We conducted a survey on tinnitus sufferers that emphasized questions related to a willingness to pay for the treatment of tinnitus, including VNS. Four hundred thirty-nine individuals responded to an Internet survey modeled after a recent study by Tyler. RESULTS: The average age was about 47 years. Ninety-four percent reported that they had health insurance. Almost 40% had spent between $500 and $10,000 on tinnitus therapies. Almost three-fourths said that they would be willing to have a device implanted if it reduced tinnitus annoyance by half. About 70% of those with very loud tinnitus would be willing to have a temporary implant, and about 60% would be willing to have a permanent implant even if the device suppressed their tinnitus by only half of its annoyance. Only 10% of patients with SOFT tinnitus would be willing to have a permanent implant if the therapy suppressed their tinnitus by only half of its annoyance. CONCLUSIONS: We conclude that implanted devices, such as a VNS, will be an acceptable form of tinnitus treatment for many who suffer from tinnitus. The results of this survey indicate that VNS tone pairing would be an acceptable therapeutic solution for individuals with moderate to severe tinnitus and should be developed for the market.

Wireless peripheral nerve stimulation increases pain threshold in two neuropathic rat models.

Neurostimulation approaches including spinal cord and peripheral nerve stimulation are typically used to treat intractable chronic pain in individuals who are refractory to pain medications. Our earlier studies have shown that a voltage controlled capacitive discharge (VCCD) method of stimulation of nerve activation is able to selectively recruit activity in large myelinated nerve fibers. In this study, we were able to wirelessly activate the sciatic nerve using the VCCD waveform. The purpose of this study was to determine whether this waveform can effectively improve two of the most troublesome pain symptoms experienced by patients with chronic neuropathic pain mechanical and cold hyperalgesia. Neuropathic mechanical hyperalgesia was reproduced using the Spinal Nerve Ligation (SNL) rat model whereas cold allodynia was reproduced using the Chronic Constriction Injury (CCI) model in male rats. Von Frey and cold plate tests were used to evaluate paw withdrawal threshold and latency to withdrawal before and after stimulation in experimental and control rats. Paw withdrawal threshold increased significantly compared to post-lesion baseline after VCCD stimulation in SNL rats. We also observed a significant improvement in cold allodynia in the active implant CCI rats after stimulation. These results suggest that the VCCD stimulation using a wireless microstimulator may be effective in the treatment of neuropathic pain.

A voltage-controlled capacitive discharge method for electrical activation of peripheral nerves.

OBJECTIVES: A voltage-controlled capacitive discharge (VCCD) method was investigated as an alternative to rectangular stimulus pulses currently used in peripheral nerve stimulation therapies. METHODS AND MATERIALS: In two anesthetized Gottingen mini pigs, the threshold (total charge per phase) for evoking a compound nerve action potential (CNAP) was compared between constant current (CC) and VCCD methods. Electrical pulses were applied to the tibial and posterior cutaneous femoralis nerves using standard and modified versions of the Medtronic 3778 Octad. RESULTS: In contrast to CC stimulation, the combined application of VCCD pulses with a modified Octad resulted in a marked decrease (-73 ± 7.4%) in the stimulation threshold for evoking a CNAP. This was consistent for different myelinated fiber types and locations of stimulation. CONCLUSIONS: The VCCD method provides a highly charge-efficient means of activating myelinated fibers that could potentially be used within a wireless peripheral nerve stimulator system.