Registration and Subtraction of Serial Magnetic Resonance Images of the Brain: Image Interpretation and Clinical Applications - Medical Image Registration - page 166

TABLE 7.1
Typical Appearances of Changes on Difference Images

Throughplane Border
Zone Shift

Inplane Border Zone
Shift Cause Pure Change in Signal Intensity Interplateau Shift

Overall appearance Nonspecific change in signal intensity Monophasic curvilinear

change

Multiphasic curvilinear
change

Interplateau change

Signal intensity Often monophasic (locally)

Variable

Monophasic (locally)
Less than full scale

Multiphasic (locally)
Less than full scale

Monophasic (locally)
Full scale

Site Anatomic

Physiologic
Pathologic
Distribution

Inplane plateau but
throughplane
border zone

Ventricular margin
Brainstem margin etc.

Cerebral cortex
Cerebellar hemisphere
etc.

Brain margins, i.e.,
around ventricles and
subarachnoid space
(for brain/CSF)

Shape Variable Curvilinear Curvilinear Follows brain margins

(for brain/CSF)

Size Variable Local size of border

zone

Local size of border
zone

Often extensive, but may
be local with or without
reversed phase

Segments Depends on anatomy,

physiology,
pathology

Mottled, patchy, or
circumscribed area

Narrower curvilinear
directional
dependence

Broader curvilinear
etched, bas relief,
directional shadowing

Uniform central region

Notes:
(i) Shifts are shown from smallest (pure change in signal intensity) to largest (interplateau).
(ii) The specificity of appearances also increases from left to right across the page.
(iii) Interplateau shifts may be throughplane and or inplane and are accompanied by smaller changes due to throughplane and inplane border zone shifts.

(iv) Throughplane border zone shifts produce a heterogeneous range of appearances, i.e., nonspecific change in signal intensity as well as monophasic
and multiphasic curvilinear changes.