Collapsed Jugular Vein and abnormal cerebral blood flow changes in patients of Panic Disorder Yu-Chien Tsao a, b, c, 1 , Chih-Ping Chung b, c, *, 1 , Hung-Yi Hsu d, e , Chun-Yu Cheng c, f , A-Ching Chao g , Wen-Yung Sheng b , Han-Hwa Hu b, c , Chen-Jee Hong c, h , Jaw-Ching Wu c, i a Department of Internal Medicine, Yonghe Cardinal Tien Hospital, Taipei 234, Taiwan b Department of Neurology, Neurological Institute, Taipei Veterans General Hospital, Taipei 11217, Taiwan c School of Medicine, National Yang-Ming University, Taipei 11217, Taiwan d Department of Neurology, Tungs' Taichung Metro Harbor Hospital, Taichung 435, Taiwan e School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan f Internal Medicine Department, Cheng Hsin General Hospital, Taipei 112, Taiwan g Department of Neurology, Kaohsiung Medical University Chung-Ho Memorial Hospital, Kaohsiung 807, Taiwan h Department of Psychiatry, Taipei Veterans General Hospital, Taipei 11217, Taiwan i Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 11217, Taiwan article info Article history: Received 14 May 2014 Received in revised form 22 July 2014 Accepted 30 July 2014 Keywords: Jugular vein Panic disorder Cerebral blood flow abstract Objective: Panic disorder (PD) is characterized by panic attacks accompanied with respiratory symptoms. Internal jugular vein (IJV) alters its hemodynamics in response to respiration and which might cause cerebral blood flow (CBF) changes. In the present study, we compared (1) respiratory-related IJV he- modynamics and (2) CBF changes during Valsalva maneuver (VM) between PD and normal subjects. Methods: 42 PD patients and age/gender-matched controls (14 men; 52.3 ± 11.4 years) were recruited. Duplex ultrasonography measured time-averaged mean velocity (TAMV) and lumen in IJV at baseline and deep inspiration. Lumen area <0.10 cm 2 at deep inspiration was defined as IJV collapse. CBF changes during VM were recorded by transcranial Doppler (TCD). Results: Compared with normal group, PD patients had significantly higher frequency of IJV collapse at deep inspiration (Left: 40.0% vs. 7.0%, p ¼ 0.0003, Right: 17.0% vs. 0%, p ¼ 0.0119). IJV collapse was associated with symptoms of respiratory subtype in our PD patients. PD group also had smaller lumen (Left: 0.53 ± 0.29 vs. 0.55 ± 0.26 cm 2 , p ¼ 0.8296, Right: 0.63 ± 0.36 vs. 0.93 ± 0.45 cm 2 , p ¼ 0.0014) and slower TAMV of IJV at baseline (Left: 11.8 ± 8.43 vs. 20.6 ± 16.5 cm/s, p ¼ 0.0003, Right: 15.9 ± 9.19 vs. 24.1 ± 15.7 cm/s, p ¼ 0.0062). PD patients with inspiration-induced IJV collapse had more decreased CBF during VM compared with the other PD patients and normal individuals respectively. Interpretation: We are the first to show that PD have less IJV flow at baseline and more frequent collapse at deep inspiration. Inspiration-induced IJV collapsed was associated with CBF decrement during VM in PD patients. These results suggest that venous drainage impairment might play a role in the patho- physiology of PD by influencing CBF. © 2014 Elsevier Ltd. All rights reserved. 1. Introduction Panic disorder (PD) is characterized by recurring panic attacks accompanied with several autonomic and cardio-respiratory symptoms. (American Psychiatric Association, 2000) Dyspnea with following dizziness/fainting is a core feature of panic attacks and a common chief complaint of PD patients encountered in clinics. (Ley, 1985) The pathophysiology of PD is yet not understood though extensive observations and researches. Several abnormal respiratory-related physiologies have been found involved in the pathophysiology of PD, which include hyperventilation with hypocapnic alkalosis, underlying pulmonary diseases (e.g. COPD), increased central CO2 sensitivity, exaggerated cerebrovascular re- sponses to hypocapnia, changes of the central rhythm generator, and dysfunctional opioid system sensitivity. Many of these * Corresponding author. Department of Neurology, Taipei Veterans General Hospital, No. 201, Sec. 2, Shih-Pai Road, Taipei 112, Taiwan. Tel.: þ886 2 2875 7583; fax: þ886 2 2873 9241. E-mail addresses: cpchung@vghtpe.gov.tw, pin324pin324@gmail.com (C.-P. Chung). 1 These authors have same contributions. Contents lists available at ScienceDirect Journal of Psychiatric Research journal homepage: www.elsevier.com/locate/psychires http://dx.doi.org/10.1016/j.jpsychires.2014.07.026 0022-3956/© 2014 Elsevier Ltd. All rights reserved. Journal of Psychiatric Research 58 (2014) 155e160