Vestibular schwannoma: Optimizing tumor growth monitoring by volume measurements

Vestibular schwannomas are diagnosed more frequently nowadays, merely due to the increased practice of magnetic resonance imaging (MRI). A conservative “wait and scan policy” is more often proposed, in which symptoms are monitored and growth is followed with successive MRI. The rationale of this treatment is that symptoms may be minimal and growth is usually indolent. Intervention may therefore be avoided. Reliable judgements according to possible growth on these scan policies are essential because invasive treatment decisions are based on these observations. Currently, two dimensional measurements are used in clinical practice, which are less reliable compared to volume measurements. Therefore, volume measurements should be used in the follow up of vestibular schwannomas. Software costs and the time factor to calculate the VS volume limits the usage of volume measurements nowadays, although developments and software improvements will ease a widespread utilisation in the near future.