The evolution of clinical functional imaging during the past 2 decades and its current impact on neurosurgical planning

Abstract

BOLD fMRI has, during the past decade, made a major transition from a purely research imaging technique to a viable clinical technique used primarily for presurgical planning in patients with brain tumors and other resectable brain lesions. This review article briefly examines the history and evolution of clinical functional imaging, with particular emphasis on how the use of BOLD fMRI for neurosurgical planning has changed during the past 2 decades. Even more important, this article describes the many published studies during that same period that have examined the overall clinical impact that BOLD and DTI have made on surgical planning.

Fig 1.

Multiplanar views of language BOLD activation overlaid on FA-weighted color directional diffusion maps superimposed on postgadolinium 3D magnetization-prepared rapid acquisition of gradient echo high-resolution anatomic images in a patient with a left trigonal intraventricular mass. The BOLD paradigm used is a silent word-generation task. Red-green-blue coding convention is used for DTI display, in which red refers to mediolateral; blue, to superoinferior; and green, to anteroposterior preferential diffusion. Note the activation of both Broca and Wernicke areas in the left hemisphere in this left-language-dominant patient.

Fig 2.

BOLD activation maps imported into a neuronavigation system. A, Hand motor activation from an alternating finger-tapping paradigm, with the 3D cursor placed on activation seen anterior to a left parietal lobe tumor. B, Language activation (combination of silent word-generation and rhyming tasks), with the 3D cursor on temporal lobe receptive cortical activation, in close proximity to the classic Wernicke area.