Abstract
The recent advancement of ultrasonographic imaging equipment has provided accurate visualization and characterization of the intimal plaques of the cervical carotid arteries. Because the soft plaques may easily cause embolic occlusion of the distal cerebral arteries during manipulation of the stenotic carotid arteries, it is important to predict the character of the carotid plaques for the safe PTA/STENT procedures. In this study, we examined patients who underwent carotid endarterectomy (CEA) with ultrasonographic imagings preoperatively. The macroscopic findings of the obtained carotid artery plaques and the preoperative ultrasonographic findings were compared to elucidate the diagnostic ability and clinical usefulness of the ultrasonography in this disorder.
Twelve patients with 14 lesions who underwent CEA were examined preoperatively by ultrasonography (TOSHIBA SSA370A, linear probe of 7.5 MHz). There were 10 men and 2 women, aged from 64 to 73 years. Ultrasonographic findings of the plaques could be classified as “hyper,” “iso,,” “low,” or “mixed,” intensity by the character, and as “smooth,” or “irregular,” plaques by the configuration. The perioperative macroscopic findings of the plaques were characterized as “fragile,” or “tough.,” The ultrasonography showed 3 lesions with low intensity and 4 lesions with mixed intensity, including low intensity. These 7 lesions were fragile in the macroscopic findings. Five lesions showing iso intensity by the ultrasonography did not include fatty degeneration or internal bleeding of the plaques and were judged as tough plaques. The ultrasonography was able to detect an ulcer of plaque.
Micro embolisms such as the fat in plaque or the thrombus can occur in the operation, and it is said that the complications of the cerebral embolisms caused by them are a serious problem of PTA. The exclusion of the high-risk group by ultrasonography examination is the most important factor in doing PTA/STENT safely. From the findings by ultrasonography and the perioperative macroscopy, we can classify “safety,” or “danger,” in each plaque to perform PTA/STENT.
We judged the fragile plaques too dangerous for PTA/STENT. We can fully satisfy the character diagnosis of the carotid plaques by ultrasonography in estimating the safeness for the intravascular operation. The probability that complications by micro embolisms occur will be high when performing PTA/STENT in low-intensity plaques. We should exclude such cases from indication of PTA/STENT in future.
