Atheromatous pseudo-occlusion of the internal carotid artery.

Abstract

Between 1978 and1988, the diagnosis of atheromatous pseudo-occlusion of the internal carotid artery was made in 34 patients by angiography. Results of noninvasive tests were abnormal in 33 of the 34 patients examined. Twenty-five patients had carotid endarterectomy, and the other nine were treated medically. Four of the 34 patients (12%) had significant complications, two related to angiography and two to surgery. Twenty-three of the 25 operated patients were seen in long-term follow-up; 19 (83%) were found to have a patent operated vessel by noninvasive testing. None of the 23 operated patients followed up suffered recurrent neurologic deficits following surgery; two had distant contralateral strokes. Three of the nine patients treated medically (33%) experienced delayed ipsilateral stroke. This study shows that the risks associated with angiography and surgery for atheromatous pseudo-occlusion are significant and are higher than previously reported. (Stroke 1989;20:1168-1173 H ighly stenotic but patent internal carotid arteries (ICAs) can easily be misdiagnosed as occluded by both noninvasive testing and by angiography. Blood flow distal to a site of extreme stenosis may be so minimal that it remains undetected. The term "atheromatous pseudo-occlusion" was first used by Lippman et al in 1970.] They described layering of contrast material along the dependent posterior wall of the ICA distal to a site of high-grade stenosis at the time of angiography. Other descriptive terms used to categorize the angiographic appearance of such extremely stenotic lesions are the poststenotic slim sign, the string sign, and the nearly occluded carotid artery.2 -8 Once identified, urgent carotid endarterectomy seems to be automatically accepted as appropriate for pseudo-occlusion. However, surgery for pseudo-occlusion should be attempted only if surgically treated patients are shown to have better prognoses than those treated medically and if longterm patency of the operated vessel is high. These issues have not been previously addressed.This report describes our experience with 34 patients with atheromatous pseudo-occlusion. All 34 underwent selective carotid angiography, and 25 subsequently had carotid endarterectomy. We report on the complications associated with both procedures. We also report the long-term clinical out-

Carotid Near-Occlusion: A Comprehensive Review, Part 1—Definition, Terminology, and Diagnosis

“…1,2,4,6,[9][10][11][12][13][14][15][16][17][18][19][20]28,31,45,[47][48][49][50][51]55,59,60,62,64,68,69,71,72 Pseudo-Occlusion. The term "pseudo-occlusion" was used for cases with raised intracranial pressure by Newton and Couch in 1960.…”

“…Images from Sekhar et al can be called "near-occlusion with full collapse." "Pseudo-occlusion" has been used for the appearance of a collapsed artery, [1][2][3][4][5][6][7][8][9]11,[13][14][15][16][17][18][19][20][45][46][47][48][56][57][58][59][60][61][62][65][66][67][68][69][70] but also quite literally when diagnosis changed from occlusion to patent after re-review (not necessarily with distal collapse. 10,12,55,63,64,81 String Sign.…”

“…1 Various terms have been used to describe near-occlusion, which can mislead students or those doing literature searches: near-occlusion (or "near total occlusion" [45][46][47][48][49][50][51] ), pseudo-occlusion, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]43,45,47,48,50-70 string sign, 1-5,7,9-13,16,18-20,22,24,26,30, 11,12,18,45 99% stenosis, 66 hairline residual lumen, 20,43 and incomplete occlusion. 1 Calculating percentage stenosis for carotid near-occlusion is fallacious, and near-occlusion assessment is advised before measuring for percentage stenosis.…”

Carotid Near-Occlusion: A Comprehensive Review, Part 2—Prognosis and Treatment, Pathophysiology, Confusions, and Areas for Improvement

“…In fact, no risk of recurrent stroke was reported. 6 In 1989, O'Leary et al 7 reported that of 9 patients with near-occlusion (most likely with full collapse) who did not undergo carotid endarterectomy, 2 had an angiographic stroke and 3 had a recurrent ipsilateral stroke within 1 year. Presumably, the angiographic strokes affected further management.…”

“…Indeed, because only approximately half (n Ϸ 8) of the near-occlusions with full collapse were observed without an operation in NASCET and ECST, and Ringelstein et al 6 did not report the risk of recurrent stroke, the risk of recurrent stroke without or before carotid endarterectomy has only been reported for approximately 27 patients. 1,3,7 Of these, 26% (7/27; 95% CI, 8%-44%) had a recurrent stroke within 1 year-ie, roughly equal to the 3-year risk of 70%-99% stenoses (but with a wide margin of error). If anything, 26% might be an underestimation because some were not followed for a full year and some were not followed from the presenting event.…”