Effective time window in reducing pituitary adenoma size by gamma knife radiosurgery

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

17 Scopus Citations
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Author(s)

  • Henry Ka-Fung Mak
  • Shui-Wun Lai
  • Wenshu Qian
  • Stanley Xu
  • Elizabeth Tong
  • May Lee Vance
  • Edward Oldfield
  • John Jane
  • Jason Sheehan
  • Max Wintermark

Related Research Unit(s)

Detail(s)

Original languageEnglish
Pages (from-to)509-517
Journal / PublicationPituitary
Volume18
Issue number4
Online published27 Sep 2014
Publication statusPublished - Aug 2015

Abstract

Objectives: Although the effectiveness of gamma knife radiosurgery (GKRS) in controlling the size of pituitary adenomas has been well demonstrated in many studies, the time period in which significant changes in tumor size occurs has been investigated in a limited fashion. It is important to determine the therapeutic window of GKRS in treating pituitary adenomas, i.e., the effective timeframe during which significant size reduction of these tumors occurs, so that alternative treatments such as further GKRS or microsurgery might be prescribed in a timely manner if clinically indicated. Methods: This was a nested sample of an ongoing local cohort study on GKRS for pituitary adenomas at the University of Virginia. Magnetic resonance imaging (MRI) using dedicated sequences was employed. Only patients with a baseline MRI (TP0) and at least 1 follow-up study performed in the University Hospital after GKRS were included. The follow-up scans were performed at five time-points (TP1–TP5) which were 6, 12, 24, 36 and 48 months after GKRS. The dimensional indices of the tumors were measured in three orthogonal planes, i.e., transverse (TR), antero-posterior (AP) and cranio-caudal (CC). The volumes of the tumors were estimated by using the following formula: $${\text{V}} = \pi\,({\text{TR}} \times {\text{AP}} \times {\text{CC}})/6$$V=π(TR×AP×CC)/6. Tumor volume decrease by more than 25 % from baseline was considered as ‘shrinkage’,

Research Area(s)

  • Gamma knife radiosurgery, Magnetic resonance imaging, Pituitary adenoma, Therapeutic time window, Tumor control

Citation Format(s)

Effective time window in reducing pituitary adenoma size by gamma knife radiosurgery. / Mak, Henry Ka-Fung; Lai, Shui-Wun; Qian, Wenshu; Xu, Stanley; Tong, Elizabeth; Vance, May Lee; Oldfield, Edward; Jane, John; Sheehan, Jason; Yau, Kelvin K. W.; Wintermark, Max.

In: Pituitary, Vol. 18, No. 4, 08.2015, p. 509-517.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review