In vitro 1H-magnetic resonance spectroscopy of Barrett's esophageal mucosa using magic angle spinning techniques.
OBJECTIVE
In vitro proton magnetic resonance spectroscopy (MRS) allows changes in cell membrane lipid structure associated with dysplasia and malignant transformation to be investigated. Magic angle spinning (MAS) MRS allows small esophageal tissue specimens to be studied directly without the need to extract the tissue, but it is not known how intact the tissue architecture remains after MAS. We report the first prospective MAS MRS study of Barrett's esophagus using endoscopic biopsies with direct histological correlation.


METHODS
Biopsies were obtained during surveillance esophagoscopy from Barrett's epithelium and adjacent normal squamous epithelium in 16 patients (34 samples). High-resolution MAS MRS was performed at 500 MHz. Following MRS, the histology was evaluated. A further, separate group of 14 biopsies were examined histologically to assess architectural damage caused by tissue preservation alone.


RESULTS
For squamous and Barrett's epithelium, respectively, metabolite ratios of choline-containing compounds to creatine plus phosphocreatine (Cho/Cr) were 1.99 and 5.65 (P < 10) and methyl lipid to creatine plus phosphocreatine ratios (lipid-CH3/Cr) were 4.07 and 7.4 (P < 10). There was no significant difference in histological preservation between the squamous and Barrett's mucosa without MRS (z = 0.67, P = 0.61), but significant differences were found post-MAS MRS (z = 4.06, P < 0.0001).


CONCLUSIONS
Squamous and Barrett's epithelium can be distinguished metabolically, based on Cho/Cr and lipid-CH3/Cr ratios. Although MAS does affect the histological architecture in Barrett's epithelium, compared with squamous epithelium, direct histological assessment was possible in the majority of samples.
Division of Medicine A, Faculty of Medicine, Imperial College London, Hammersmith Hospital Campus, London, UK.
Umakant
U
Dave
Simon D
SD
Taylor-Robinson
Marjorie M
MM
Walker
Marrita
M
Mahon
Basant K
BK
Puri
Mark R
MR
Thursz
Nandita M
NM
DeSouza
I Jane
IJ
Cox
D000328:Adult; D000368:Aged; D001471:Barrett Esophagus / Q000473:pathology*; D001706:Biopsy / Q000379:methods; D002794:Choline / Q000032:analysis; D003401:Creatine / Q000032:analysis; D004848:Epithelium / Q000737:chemistry / Q000473:pathology; D004945:Esophagoscopy / Q000379:methods; D004947:Esophagus / Q000737:chemistry / Q000473:pathology; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010725:Phosphocreatine / Q000032:analysis; D011446:Prospective Studies; D014280:Triglycerides / Q000032:analysis
D014280:Triglycerides; D010725:Phosphocreatine; D003401:Creatine; D002794:Choline