With the increasing use of carotid artery stenting (CAS), carotid duplex ultrasound (CDU) is important for post-stented patients to check the patency of CAS. In our institute, stented patients were treated with dual antiplatelet therapy for 3 months after CAS. Follow-up on 3-dimensional computed tomography (3D-CT) angiography was performed around 2 years after CAS. Some patients were also followed up annually with CDU. Although the major complication of CAS is reportedly in-stent restenosis (ISR), definitions of ISR have not been standardized. From the perspective of long-term follow-up of stented vessels, we considered in-stent intimal hyperplasia (ISH) as more important for patients than ISR. We therefore studied the clinical features of ISH in comparison with normal stented vessels. CAS was performed for 158 vessels (117 patients) in our hospital from 2009 to 2013. Patients who underwent simple balloon angioplasty, experienced CAS failure or arterial dissection, or had no data available from CDU were excluded. We defined ISH from CDU as a maximum in-stent plaque thickness > 1.1 mm during follow-up. Subjects were divided into an ISH group (n=43) and normal stented group (n=79). The ISH group showed significantly lower age and higher concentration of LDL than the normal group. Next we studied changes over time for in-stent plaque thickness. ISH was uniformly < 2.0 mm during the first 2 years, but 3 cases showed increases to ≤ 3.0 mm by 4 years after CAS. In conclusion, attention must be paid to increments in ISH during long-term follow-up.
Purpose: Image evaluation of post-carotid artery stenting (CAS) using non-invasive carotid ultrasonography is widely performed. Three types of carotid artery stents are currently used in Japan: “Carotid WALLSTENT,” “PRECISE,” and “PROTEGE.” Shapes and materials differ for each stent. On post-CAS ultrasonography, findings differ by stent type. We compared ultrasonographic images for each type. Methods: We weighed B-mode and color Doppler images with each stent type. And, in patients with in-stent plaque, ultrasonographic images were compared with CT angiography. Moreover, a stent was fixed underwater, and long- and short-axis views from a 12-MHz linear probe were examined. Results: The Carotid WALLSTENT showed fewer artifacts and was best observed in B-mode. In some cases, observation of in-stent plaque was difficult without B-flow or color Doppler imaging. Near-wall artifacts were most frequently observed in PROTEGE. Furthermore, depiction of color flow within PRECISE or PROTEGE was poor, because these stents were curved in accordance with the vessel wall in the proximal portion of the internal carotid artery. Conclusions: Ultrasonographic images differ according to stent type. Ultrasonography must be performed with an understanding of the features and ultrasonic image characteristics of the stents involved.
Introduction: On August 25, 2011, Typhoon No.12 hit the village of Kitamata in Nosegawa, Nara Prefecture, Japan. Residents were forced to seek long-term shelter in evacuation facilities because of sediment runoff in the district. Authorities feared that these residents might have developed deep venous thrombosis (DVT). Thus, DVT screening was conducted among the residents in order to examine factors related to the occurrence of DVT among residents in landslide-affected areas. Methods: Among the residents, 33 were eligible for DVT screening. A portable ultrasonography equipment was used to explore for possible DVT in the soleal vein on both sides and measure its maximum diameter. Results: Of the 33 subjects, 3 (9.1%) had DVT, out of which 2 had fresh thrombi. On ultrasonography, all 3 patients (100%) had soleal vein extension of greater than 8mm and tested positive for DVT. However, no significant difference in soleal vein extension was found in comparison with the 11 patients (36.7%) who tested negative for DVT (p=0.0667). Conclusion: In the residents in this study who stayed in evacuation facilities over a long period after the landslide in their area, fresh DVT was confirmed. In addition, we identified soleal vein extension as a possible factor for the occurrence of DVT.
Introduction: The aim of this study is to clarify the important role of deep venous thrombosis (DVT) in disaster refugees. Methods: We visited the Minami-sanriku Tome shelter in Miyagi Prefecture, one of the areas affected by the Great East Japan Earthquake, to examine the incidence of DVT by using an ultrasound device from March 14 to May 4, 2011. One hundred eighty-seven people, who were aged over 60 years and had lower limb trauma, lower limb symptoms, a history of lengthy periods of resting inside a car, and/or a motionless lifestyle in the shelter, participated in the examination. The ultrasound examination was mainly intended to check for DVT findings below the knee. Results: The incidence of DVT in the participants was 5.3% (10/187). When comparing those with DVT with those without, age, percentage of women, and percentage with lower limb trauma were significantly higher in DVT patients than in non-DVT people. After logistic regression analysis, lower limb trauma was an independent strong risk factor for DVT (p < 0.0001, odds ratio=26.5). Conclusion: In conclusion, lower limb trauma is the most important cause of DVT formation in disaster refugees.
A 54-year-old man with untreated hypertension presented to our emergency room with dizziness and vomiting. Neurological findings were essentially normal, so the peripheral vertigo was treated with sodium bicarbonate. However, symptoms persisted 6 h later, so magnetic resonance imaging (MRI) was performed. Blood pressure was 149/90mmHg, electrocardiography showed sinus rhythm, and no specific changes in the blood were evident. Nystagmus was the only neurological sign, but MRI revealed acute ischemic lesions in the territory of the right posterior inferior cerebellar artery. Visualization of the right vertebral artery (VA) was poor on MR angiography. Carotid duplex ultrasonography showed to and fro movement of the right VA, and transcranial color flow imaging revealed reversed and flattened flow in the right intracranial VA. Three sequential ultrasonographic assessments showed gradual increases in intracranial reversed VA flow (RVAF), with concomitant decreases in extracranial VA flow. The angiographic findings of stenosis and dilation in the right-origin VA indicated a diagnosis of VA dissection. Intracranial RVAF is quite frequently associated with VA dissection. Ultrasonographic follow-up to detect changes in intracranial RVAF is useful for evaluating the hemodynamic status of patients with acute VA dissection.