A brief description of different methods (in use or proposed) of radiological assessment of X-linked ALD. By Felice D'Arco Pediatric neuroradiology consultant Great Ormond Street Hospital London

1. Beyond Loes score
felice.d’arco@gosh.nhs.uk
http://www.slideshare.net/bluetango84

2. Summary
o What’s X-ALD
o MRI features of X-ADL
o Loes score: still the gold standard?
o Evidence of advanced MRI techniques
usefulness in X-ALD

3. What is X-ALD?
o ABCD 1 gene mutation (chromosome X)
o Peroxisomal membrane protein
VLC fatty acids
Peroxisome
Short fatty
acids
Proteins and lipids
ABCD1
Accumulation/toxicity

4. Toxicity in brain = demyelination
MRI surrogate of histological changes !
First central and posterior
involvement: Splenium,
Peritrigonal white matter and
Thalami
… then centrifugal extension

5. Toxicity in brain = demyelination
MRI surrogate of histological changes !
Zone A: Burned out zone of scarring, Hyper FLAIR/T2, increased MD, reduced FA,
no restriction
Zone B: active inflammation, enhancement and restriction
Zone C: ongoing demyelination but no inflammation (images similar to A)

6. Variability in MRI picture
Barkovich AJ, Raybaud C 2012

7.  No diffusion
 No advanced techniques
 T1, T2 and contrast changes
all the same “weight”
 Loes score < 7  BMT
 Loes score does not take in
account location
 Involvement of CST is
associated with poorer
prognosis (Kuhl et al.2017)

8. Multiparametric approach in evaluation of X-ALD
1) Contrast enhancement
More enhancement - more inflammation
Miller et al AJNR 2016
“In boys with higher-
risk cerebral disease
(Loes ≥ 10),
enhancement score
itself
predicts neurologic
outcome following
treatment.”

9. Multiparametric approach in evaluation of X-ALD
2) MRS
Metabolic profile predictor of severity of the disease

10. “changes in the markers enabled detection of early
neurochemical changes in lesion formation prior to
detection of abnormalities by conventional MRI.” Ox et al
2005

11. Multiparametric approach in evaluation of X-ALD
3) Diffusion Tensor Imaging
changes in diffusion tensor measurements might be useful to predict the disease
progression. (Ono et al. 2014)
Demyelination:
1) ↓FA
2) ↑MD
Possible early predictor
of disease.
Opposite changes in
inflammation edge ??
Importance of the ROI
analysis and placement
!!
You know the
pathophysiology, you
know how to interpret
imaging results

12. Multiparametric approach in evaluation of X-ALD
4) Perfusion Imaging
Hypoperfusion predicts lesion progression in X-ALD. (Musolino et al. 2012; McKiney
et al. 2016)
“Decreased brain
magnetic resonance
perfusion in cerebral
adrenoleukodystrophy
precedes lesion
progression”
No clinical data on ASL

13.  We should use our experience in multiparametric
imaging for brain tumors in radiological assessment
of X-ALD
Take Home messages
Contrast
enhancement
Loes Score
MRS
Diffusion Tensor Imaging
Perfusion Imaging
Comprehensi
ve
assessment
of patients
with X-ALD

14. Thank you