Transcranial MR-Guided Focused Ultrasound and Hyperostosis Calvariae Diffusa: Case Report and Systematic Review of the Literature

Stereotact Funct Neurosurg. 2022;100(5-6):331-339. doi: 10.1159/000527232. Epub 2022 Dec 15.


We describe a 74-year-old male with intractable essential tremor (ET) and hyperostosis calvariae diffusa who was unsuccessfully treated with magnetic resonance-guided focused ultrasound (MRgFUS). A computed tomography performed prior to the procedure demonstrated a skull density ratio (SDR) of 0.37 and tricortical hyperostosis calvariae diffusa. No lesion was evident on post-MRgFUS MRI, and no improvement in the patient's hand tremor was noted clinically. We systematically reviewed the literature to understand outcomes for those patients with hyperostosis who have undergone MRgFUS. A comprehensive literature search using the PubMed, Cochrane, and Google Scholar databases identified 3 ET patients with hyperostosis who failed treatment with MRgFUS. Clinical findings, skull characteristics, treatment parameters, and outcomes were summarized, demonstrating different patterns/degrees of bicortical hyperostosis and variable SDRs (i.e., from 0.38 to ≥0.45). Although we have successfully treated patients with bicortical hyperostosis frontalis interna (n = 50), tricortical hyperostosis calvariae diffusa appears to be a contraindication for MRgFUS despite acceptable SDRs.

Keywords: Essential tremor; Hyperostosis calvariae diffusa; MR-guided focused ultrasound; Skull density ratio; Skull volume.

Publication types

  • Systematic Review
  • Case Reports

MeSH terms

  • Aged
  • Essential Tremor* / surgery
  • Humans
  • Hyperostosis* / diagnostic imaging
  • Magnetic Resonance Imaging / methods
  • Male
  • Neurosurgical Procedures / methods
  • Skull / diagnostic imaging