Combined assessment by transcranial sonography and Sniffin' Sticks test has a similar diagnostic accuracy compared to brain SPECT for Parkinson's disease diagnosis

• Published in: Clinical neurology and neurosurgery Vol. 220; p. 107333
• Main Authors: Almeida, Kelson James, Bor-Seng-Shu, Edson, Pedroso, José Luiz, Felicio, Andre Carvalho, de-Lima-Oliveira, Marcelo, Barsottini, Orlando Graziani Povoas, de Carvalho Nogueira, Ricardo, Paschoal-Júnior, Fernando Mendes, Borges, Vanderci, Batista, Ilza Rosa, Teixeira, Manoel Jacobsen, Ferraz, Henrique Ballalai, Walter, Uwe
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Limited 01-09-2022
• Subjects: Accuracy; Age; Brain - diagnostic imaging; Cross-Sectional Studies; Diagnosis; Dopamine; Female; Humans; Male; Middle Aged; Movement disorders; Neostriatum; Neurodegenerative diseases; Neurology; Outpatient care facilities; Parkinson Disease - diagnostic imaging; Parkinson's disease; Patients; Single photon emission computed tomography; Statistical analysis; Substantia nigra; Tomography; Tomography, Emission-Computed, Single-Photon - methods; Ultrasonic imaging; Ultrasonography, Doppler, Transcranial - methods; Tomography; Substantia nigra; Parkinson; Ultrasonography; Smell
• ISSN: 0303-8467; 1872-6968
• DOI: 10.1016/j.clineuro.2022.107333

This study aimed to investigate the accuracy of TCS combined with the Sniffin' sticks olfactory test (SST-16) for differentiation between idiopathic PD patients and healthy controls compared to that of
Tc-TRODAT-1 SPECT (TRODAT).
A cross-sectional study included PD patients diagnosed in accordance with United Kingdom PD Society Brain Bank criteria and a control group of age and sex- matched healthy subjects. All patients were examined by a movement disorder specialist and underwent brain SPECT using TRODAT, TCS examination and SST-16 test. Receiver Operating Characteristic (ROC) curves were used to calculate cut-off points for TCS, striatal TRODAT binding potentials and SST-16. The area under the ROC curve determined the diagnostic accuracy of the method.
Twenty patients with PD (13 males and 7 females) and nine healthy subjects were included. Median age of PD onset was 56.5 years with median disease duration of 5 years. A larger substantia nigra (SN) echogenic area was observed in the PD group (p = 0.013). SN echogenic area cut-off point of 0.22 cm
was obtained from a ROC curve for PD diagnosis. Considering this cut-off point, TCS diagnostic accuracy was estimated at 79.2% for PD diagnosis. The cut-off value of 0.90 for striatal TRODAT binding was associated with 99% diagnostic accuracy for the diagnosis of PD. SST-16 values equal or less than 9 points showed an 85.8% diagnostic accuracy for PD diagnosis. Combination of both SST-16 and TCS improved the diagnostic accuracy to 95% for PD diagnosis.
Combined SST-16 and TCS assessment was indicated as accurate for distinguishing PD patients from healthy controls. The diagnostic accuracy of TCS combined with SST-16 for differentiation between idiopathic PD patients and healthy controls is similar to that of SPECT TRODAT.