Phosphorus-31 MR Spectroscopy in the Preoperative Evaluation of Symptomatic Unilateral Carotid Artery Stenosis

Abstract

Purpose:

The purpose of this study was to examine the potential of ³¹P-MRS (MR spectroscopy) in the pre- and postoperative evaluation of patients referred for endarterectomy.

Material and Methods:

Nine patients with unilateral, hemodynamically significant stenosis in the region of the common carotid bifurcation were examined pre- and postoperatively with CT, SPECT (regional cerebral blood flow), transcranial Doppler, and duplex sonography, and they also underwent neuropsychologic investigation. Phosphorus-31 MRS of each hemisphere was performed before and 27–148 days after surgery. The relative concentrations of phosphomono- and -diesters, inorganic phosphate, phosphocreatine, and ATP were estimated.

Results:

No definite changes in concentrations could be detected for any of the metabolites.

Conclusion:

The lack of changes was probably due to well-functioning collaterals and to the partial volume effect, whereby changes in a focal region are hidden when larger volumes are studied.

Keywords

Carotid artery,stenosis MR spectroscopy,phosphorus-31 endarterectomy

Get full access to this article

View all access options for this article.

References

Aaslid

: Transcranial Doppler sonography. Springer-Verlag, Vienna 1986.

Bottomley

P. A.

Drayer

B. P.

Smith

L. S.

: Chronic adult cerebral infarction studied by phosphorus NMR spectroscopy. Radiology 160 (1986), 763.

Cikrit

D. F.

Burt

R. W.

Dalsing

M. C.

: Acetazolamide enhanced single photon emission computed tomography (SPECT) evaluation of cerebral perfusion before and after carotid endarterectomy. J. Vasc. Surg. 15 (1992), 747.

European Carotid Surgery Trialist's Collaborative Group: MRC European carotid surgery trial. Interim results for symptomatic patients with severe (70–99%) or with mild (0–29%) carotid stenosis. Lancet 337 (1991), 1235.

Hemmingsen

Mejsholm

Vorstrup

Lester

Engell

H. C.

Boysen

: Carotid surgery, cognitive function, and cerebral blood flow in patients with transient ischemic attacks. Ann. Neurol. 20 (1986), 13.

Henriksen

: MR spectroscopy in clinical research. Acta Radiol. 35 (1994), 96.

Hugg

J. W.

Duijn

J. H.

Matson

G. B.

: Elevated lactate and alkalosis in chronic human brain infarction observed by ¹H and ³¹P MR spectroscopic imaging. J. Cereb. Blood Flow Metab. 12 (1992), 734.

Levine

S. R.

Helpern

J. A.

Welch

K. M. A.

: Human focal cerebral ischemia. Evaluation of brain pH and energy metabolism with P-31 spectroscopy. Radiology 185 (1992), 537.

Levine

R. L.

Rozental

J. M.

Nickles

R. J.

: Blood flow asymmetry in carotid occlusive disease. Angiology 43 (Feb. 1992), 100.

10.

Mononen

Lepojärvi

Kallanranta

: Early neuropsychological outcome after carotid endarterectomy. Eur. Neurol. 30 (1990), 328.

11.

Nighoghossian

Trouillas

Philippon

Itti

Adeleine

: Cerebral blood flow reserve assessment in symptomatic versus asymptomatic high-grade internal carotid artery stenosis. Stroke 25 (1994), 1010.

12.

North American Symptomatic Carotid Endarterectomy Trial Collaborators: Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade stenosis. N. Engl. J. Med. 325 (1991), 445.

13.

Ordidge

R. J.

Connelly

Lohman

J. A. B.

: Image-selected in vivo spectroscopy. J. Magn. Reson. 66 (1986), 283.

14.

Petroff

O. A. C.

Prichard

J. W.

Behar

K. L.

Alger

J. R.

den Hollander

J. A.

Shulman

R. G.

: Cerebral intracellular pH by ³¹P nuclear magnetic resonance spectroscopy. Neurology 35 (1985), 781.