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Updated: May 1, 2026
Controlling Parkinson's Disease With Adaptive Deep Brain Stimulation
Published on: July 16, 2014
Low-power inversion recovery MRI preserves brain tissue contrast for patients with Parkinson disease with deep brain
S N Sarkar1, E Papavassiliou2, R Rojas3
1From the Department of Radiology (S.N.S., R.R., D.L.T., D.B.H., R.A.B., J.S.) ssarkar@bidmc.harvard.edu.
Background And Purpose:
Fast spin-echo short τ inversion recovery sequences have been very useful for MR imaging-guided deep brain stimulation procedures in Parkinson disease. However, high-quality fast spin-echo imaging deposits significant heat, exceeding FDA-approved limits when patients already have undergone deep brain stimulation and need a second one or a routine brain MR imaging for neurologic indications. We have developed a STIR sequence with an ultra-low specific absorption rate that meets hardware limitations and produces adequate tissue contrast in cortical and subcortical brain tissues for deep brain stimulation recipients.
Materials And Methods:
Thirteen patients with medically refractory Parkinson disease who qualified for deep brain stimulation were imaged at 1.5T with a fast spin-echo short τ inversion recovery sequence modified to meet conditional MR imaging hardware and specific absorption rate restrictions. Tissue contrast-to-noise ratios and implant localization were objectively and subjectively compared by 2 neuroradiologists, and image quality for surgical planning was assessed by a neurosurgeon for high and low specific absorption rate images.
Results:
The mean contrast-to-noise ratio for cerebral tissues without including the contrast-to-noise ratio for ventricular fluid was 35 and 31 for high and low specific absorption rate images. Subjective ratings for low specific absorption rate tissue contrast in 77% of patients were identical to (and in a few cases higher than) those of high specific absorption rate contrast, while the neurosurgical coordinates for fusing the stereotactic atlas with low specific absorption rate MR imaging were equivalent to those of the high specific absorption rate for 69% of patients.
Conclusions:
Patients with Parkinson disease who have already had a deep brain stimulation face a risk of neural injury if routine, high specific absorption rate MR imaging is performed. Our modified fast spin-echo short τ inversion recovery sequence conforms to very conservative radiofrequency safety limits, while it maintains high tissue contrast for presurgical planning, postsurgical assessment, and radiologic evaluations with greater confidence for radiofrequency safety.
Insights
A new modified fast spin-echo short τ inversion recovery sequence offers safe MR imaging for Parkinson disease patients with deep brain stimulation. This ultra-low specific absorption rate sequence provides adequate tissue contrast, ensuring safety and effective presurgical planning.
Area of Science:
- Neurosurgery
- Radiology
- Medical Imaging
Background:
- Fast spin-echo short τ inversion recovery (STIR) sequences are crucial for MR imaging-guided deep brain stimulation (DBS) in Parkinson disease.
- High specific absorption rate (SAR) in conventional fast spin-echo imaging poses risks, exceeding FDA limits for patients needing repeat DBS or routine brain MR imaging.
Purpose of the Study:
- To develop and evaluate a modified STIR sequence with an ultra-low specific absorption rate (SAR) for safe MR imaging in DBS recipients.
- To ensure adequate tissue contrast for cortical and subcortical brain structures in Parkinson disease patients with DBS.
Main Methods:
- Thirteen Parkinson disease patients undergoing DBS were imaged at 1.5T using a modified fast spin-echo STIR sequence adhering to low SAR restrictions.
- Neuroradiologists assessed tissue contrast-to-noise ratios and implant localization objectively and subjectively.
- A neurosurgeon evaluated image quality for surgical planning, comparing high and low SAR images.
Main Results:
- The mean contrast-to-noise ratio for cerebral tissues was comparable between high (35) and low (31) SAR images.
- Subjective tissue contrast ratings for the low SAR sequence were identical or superior to high SAR in 77% of patients.
- Neurosurgical coordinates for stereotactic atlas fusion were equivalent between low and high SAR images in 69% of patients.
Conclusions:
- Modified low SAR fast spin-echo STIR MR imaging is safe for Parkinson disease patients with DBS, mitigating neural injury risks.
- The sequence meets conservative radiofrequency safety limits while maintaining high tissue contrast.
- This approach enhances confidence for presurgical planning, postsurgical assessment, and routine radiologic evaluations in DBS recipients.
