{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T22:28:12Z","timestamp":1778797692258,"version":"3.51.4"},"reference-count":63,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,11]],"date-time":"2021-06-11T00:00:00Z","timestamp":1623369600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Non-motor symptoms (NMS) in Parkinson\u2019s disease (PD), including neuropsychiatric or dysautonomic complaints, fatigue, or pain, are frequent and have a high impact on the patient\u2019s quality of life. They are often poorly recognized and inadequately treated. In the recent years, the growing awareness of NMS has favored the development of techniques that complement the clinician\u2019s diagnosis. This review provides an overview of the most important ultrasonographic findings related to the presence of various NMS. Literature research was conducted in PubMed, Scopus, and Web of Science from inception until January 2021, retrieving 23 prospective observational studies evaluating transcranial and cervical ultrasound in depression, dementia, dysautonomic symptoms, psychosis, and restless leg syndrome. Overall, the eligible articles showed good or fair quality according to the QUADAS-2 assessment. Brainstem raphe hypoechogenicity was related to the presence of depression in PD and also in depressed patients without PD, as well as to overactive bladder. Substantia nigra hyperechogenicity was frequent in patients with visual hallucinations, and larger intracranial ventricles correlated with dementia. Evaluation of the vagus nerve showed contradictory findings. The results of this systematic review demonstrated that transcranial ultrasound can be a useful complementary tool in the evaluation of NMS in PD.<\/jats:p>","DOI":"10.3390\/brainsci11060776","type":"journal-article","created":{"date-parts":[[2021,6,11]],"date-time":"2021-06-11T12:44:37Z","timestamp":1623415477000},"page":"776","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Neurosonological Findings Related to Non-Motor Features of Parkinson\u2019s Disease: A Systematic Review"],"prefix":"10.3390","volume":"11","author":[{"given":"Cristina","family":"del Toro P\u00e9rez","sequence":"first","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Laura","family":"Amaya Pascasio","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Arjona Padillo","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jes\u00fas","family":"Olivares Romero","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda","family":"Mej\u00edas Olmedo","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Javier","family":"Fern\u00e1ndez P\u00e9rez","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Manuel","family":"Pay\u00e1n Ortiz","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Patricia","family":"Mart\u00ednez-S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Neurosonology Laboratory, Department of Neurology, Torrec\u00e1rdenas University Hospital, 04009 Almer\u00eda, Spain"},{"name":"Faculty of Health Sciences, CEINSA (Center of Health Research), University of Almer\u00eda, La Ca\u00f1ada, 04120 Almer\u00eda, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S119","DOI":"10.1016\/j.parkreldis.2015.09.004","article-title":"Non-motor symptoms in Parkinson\u2019s disease","volume":"22","author":"Pfeiffer","year":"2016","journal-title":"Park. 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