Introduction: The success of deep brain stimulation (DBS) surgery greatly depends on the accuracy of intracranial targeting. Nonetheless, the DBS hardware longevity and patient satisfaction in large part rely on the technical details of the extracranial parts of the DBS surgery. One of the cosmetic and comfort issues relates to “bowstringing” or “wire tethering” - unsightly long tense subcutaneous cord where DBS extension leads course through the neck subcutaneous tissue. In our experience, it usually becomes apparent at around 4-6 weeks postoperatively and gradually worsens with the maturation of the scar tissue with reported incidences of up to 6.7%. In some extreme cases, scar revision surgery is needed. The immediate postoperative neck range of motion exercises seem to lessen the development of this complication, nonetheless, the “bowstringing” remains a risk where two DBS extension leads travel side-by-side in a single cervical tunnel. This problem led us to a modification of the technique so that each DBS extension has its own tunnel.

Methods: During the second stage of DBS surgery, the DBS extension leads are tunneled subcutaneously from the scalp incision towards the subclavicular incision for the DBS generator. We intentionally make one interim skin incision at the mastoid process level. From there the two DBS extension leads take a divergent course and then converge back at the generator site.

Results: Since the introduction of divergent DBS extension lead tunneling in April 2016, with 26 patients who underwent double DBS lead implantations, we have seen significantly improved cosmetic effects in the neck.

Conclusions: The simple adjustment of the DBS extension lead tunneling technique augments patient satisfaction. We postulate that such path separation for the distal halves of DBS extension leads redistributes tension forces in somewhat opposing directions, thus, preventing the unidirectional scar tissue contraction and tethering to the leads.

Patient Care: Improved cosmesis and patient comfort after DBS surgery

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the techniques for DBS extensions lead tunneling; 2) Discuss, in small groups, complications of DBS extensions lead tunneling; 3) Identify the strengths and drawbacks of different DBS extensions lead tunneling techniques

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