Table 14: Anatomical and functional imaging categories and examples of major disease entities associated with frontal network syndromes [3134].

(A) MRI multimodality
 MRI (routine series)
  T1/T2, FLAIR, GRE, and MRA to detect degree of concomitant vascular disease, atrophy pattern, and other secondary pathologies
 MRI—DTI
  Fiber tract pathology especially in traumatic brain injury, multiple sclerosis
 MRI quantitative atrophy estimation
  Different patterns of the major dementia syndromes (Seeley et al. [20])
 MRI—perfusion
  Perfusion as a reflection of hypometabolism, similar to SPECT (perfusion) and PET (metabolism) patterns of abnormality
 MR spectroscopy
  Biochemical analysis of NAA, choline, lactate particularly useful in brain tumor diagnosis
(B) SPECT
 Hypoperfusion (in vascular or hypometabolism)
 Hyperperfusion for example with ictal foci.
(C) PET brain
 Hypometabolic patterns in different dementias
(D) Intrinsic state connectivity maps
 Default mode
 Salience network
 Attentional network
 Visual network
 Auditory network
(E) Quantitative EEG and MEG
 AD reduced connectivity of alpha and beta in frontoparietal and frontotemporal regions
 Parkinson’s increased connectivity of alpha and beta locally and globally
 DLBD reduced connectivity alpha range locally and globally.

Adapted and modified from [31, 32].