@article{oai:dmu.repo.nii.ac.jp:00001501,
 author = {Suzuki, Ayano and Takekawa, Hidehiro and Suzuki, Keisuke and Hirata, Koichi},
 issue = {1},
 journal = {Dokkyo Journal of Medical Sciences},
 month = {Mar},
 note = {Purpose：The aim of this study was to assess the right-to-left shunts （RLs） associated with patent foramen ovale（PFO）, which is essential for diagnosing paradoxical cerebral embolisms. Transesophageal echocardiography （TEE） and transcranial Doppler （TCD） are used for the detection of RLs. However, in some patients with comorbid diseases, such as cervical spondylosis and esophageal varices, and in elderly women, TCD and TEE assessment are difficult. We compared the efficacy of carotid artery ultrasonography（C-US） and TEE in terms of the detection rate of PFO.

Methods：Fifty-eight successive patients with ischemic stroke （age：57.0±19.0 years, 38 men and 20women） were evaluated for PFO through TEE and C-US. In a TEE assessment, the diagnosis of PFO was made using the Valsalva maneuver with contrast agent injection. The internal carotid artery was evaluated with C-US. PFO was defined as the appearance of microembolic signals （MES） after release of Valsalva load with contrast agent injection.

Results：A PFO was detected in 30 patients. MES were observed in 25 patients using C-US. For the diagnosis of PFO, C-US had 83.3％ sensitivity, 100％ specificity, 100％ positive predictive value, and 93.8％ negative predictive value. In contrast, TEE had 53.3％ sensitivity, 100％ specificity, 100％ positive predictive value, and 66.7％ negative predictive value.

Conclusion：Our study suggests that C-US with Valsalva load release and contrast agent injection is beneficial for the diagnosis of PFO."},
 pages = {9--16},
 title = {Pulsed Doppler Ultrasound of the Internal Carotid Artery for the Diagnosis of Patent Foramen Ovale in Patients with Ischemic Stroke},
 volume = {45},
 year = {2018}
}