Neuroimaging in the diagnosis of ADHD: where we are and where we are going.

INTRODUCTION: Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent childhood psychiatric disorder. ADHD manifests with symptoms of inattention, hyperactivity and/or impulsivity that pervade in the familiar, academic and social spheres. There are serious concerns about the widespread misdiagnosis of ADHD that, together with the fast growing use of neuroimaging techniques in ADHD research, have prompted an inquiry into the feasibility of an imaging test for the diagnosis of ADHD that could aid in clinical practice.

AREAS COVERED: This article consists of a brief review of the main neuroimaging research findings in ADHD and its contributions to the current understanding of the ADHD neurobiology, highlighting aspects that could eventually be utilized as a basis for diagnostic tests. The paper then outlines and applies a multiphase approach for developing diagnostic imaging tests in psychiatry to evaluate their prospects for the diagnosis of ADHD as well as evaluating a recently proposed diagnostic imaging test.

EXPERT OPINION: It appears obvious that a diagnostic imaging test for ADHD should be based on the state-of-the-art neuroimaging techniques now available from ADHD neurobiology research. However, the deriviation of an imaging diagnostic tool from neuroimaging research is not as straightforward as it may seem, with several prerequisites that must be met in advance. The author suggests that a consistent decreased volume of right caudate nucleus in ADHD samples could provide a good basis for any future diagnostic imaging test.