This study tested whether substantia nigra hyperechogenicity measured by transcranial sonography can serve as a biomarker for disease progression in early onset Parkinson's disease patients. The study found that (1) substantia nigra hyperechogenicity increased progressively over time in both hemispheres of early onset Parkinson's patients initially presenting with signs in one hemisphere only, (2) this increase preceded the clinical detection of signs in the initially less affected hemisphere, and (3) transcranial sonography may be more sensitive than clinical exams alone in detecting progression from stage I to stage II of the disease.

1. EARLY ONSET PARKINSON’S DISEASE (EOPD) PROGRESSION AS MONITORED BY HYPERECHOGENICITY OF THE
SUBSTANTIA NIGRA (SN)
S. RAVI1, K. VENKITESWARAN1, V. SHIVKUMAR1, N. HARID1, T. GILMOUR1, C. LIEU1, R. SAADI1, D. DANG1, J.L. WANG2, Q. YANG2,
T. SUBRAMANIAN1
1Neurology and Neural and Behavioral Sciences, 2Radiology, Penn State Milton S. Hershey College of Medicine, Hershey, PA.
We test the hypothesis that SN hyperechogenicity can be used as a biomarker for
disease progression from stage I (unilateral parkinsonsim) to stage II (bilateral
parkinsonism) in EOPD patients.
Objective
Early Onset Parkinson’s Disease (EOPD) is characterized by disease onset at
ages >40 and <60 years. These patients have a high risk for treatment related
complications and need close monitoring for disease progression. Substantia
nigra (SN) hyperechogenicity measured by Transcranial Sonography (TCS) is an
established biomarker to differentiate PD from other forms of parkinsonism.
Many studies have shown that the SN hyperechogenicity remains greater >0.2
cm2 in area once this criteria is attained. However, the value of SN
hyperechogenicity as a disease progression marker in stage I disease EOPD
patients has not been thoroughly explored.
Methods
 A total of 27 EOPD patients who met UK Brain Bank criteria for PD, did not
have genetic forms of PD and were in stage I disease, as determined by MDS-
UPDRS and H&Y staging by an experienced movement disorder specialist
(TS), were offered this prospective single blind study. All consented patients
were examined in the “off” state. Most patients were not on any medications
(N=15), a few that were on meds (N=8) were evaluated after overnight
medication withdrawal of all anti-PD meds. Of the 27 patients who consented,
4 patients had poor acoustic window, 2 patients dropped out, and 21 patients
completed the study.
 TCS was performed and evaluated by a blinded rater using a Siemens Acuson
Sequoia Ultrasound system (2.5 MHz transducer). Planimetric measurements
of SN hyperechogenicity > 0.2 cm2 was classified as significant on each side.
Methods described by Dr. D. Berg, et. al., were utilized for the planimetric
measurements and to ensure quality several random deidentified image
captures were evaluated by Dr. Berg who provided training to KV. Planimetric
measurements were confirmed in these random checks to ensure reliability. A
full neurological exam which included MDS-UPDRS was performed at every
visit following the TCS.
 Patients were evaluated for the baseline measures at visit 1 (V1).
Subsequently, they were evaluated at visits 2 (V2), 3 (V3), and 4 (V4),
approximately 1, 1.5, and 2 years after V1,respectively. At each visit, the TCS
was performed by the blinded investigator without any knowledge of the
patient’s clinical condition and while they were optimally medicated several
hours after the “practically defined “off” evaluation was completed. To ensure
blinding, the subjects limbs were covered and conversations between the
sonographer and the subject was kept to a minimum. All data was collected
and stored without any personal identifiers. To date, we have completed 80%
of visits in all subjects. The clinical assessor (TS) was blinded to all TCS data
at every visit. Data for V1 and V2 is complete, with a few remaining V3 visits.
V4 visits have been completed only for a few subjects.
Background
Conclusions
 As noted earlier, the 2 assessments were done blinded such that the sonographer and the clinical assessor had
no knowledge of each others findings for each patient at any visits.
 In EOPD patients, who do not have any genetic forms of PD, we show that
SN hyperechogenicity is a progressive phenomenon that transitions from
<0.2cm2 value to >0.2cm2 value over variable lengths of time. This is the
first demonstration of SN hyperechogenicity serving as a disease
progression marker in any PD population.
 TCS is an inexpensive, easy to use, repeatable, and safe biomarker for
EOPD patients in stage I disease and could be a valuable tool to study
disease modifying agents for EOPD.
Representative TCS images obtained through the right (R) and left (L) temporal acoustic bone windows
showing large hyperechogenecity (encircled) on right side (contralateral) in an early onset PD patient with left
hemiparkinsonism at V1 visit. Note that the ipsilateral nigra has a much smaller hyperechogenicity that did not
meet the criteria of >0.2 cm2.
S. Ravi has nothing to disclose. Dr. Venkiteswaran has nothing to disclose. Dr. Shivkumar has nothing to disclose. Dr. Gilmour has nothing to disclose. Dr. Harid has nothing to disclose. Dr. Saadi has nothing to disclose. Dr. Subramanian has received personal compensation for activities with Teva Neuroscience, USMedWorld, and UCB Pharma as a speaker board member. Dr. Subramanian has received research support from Ipsen, and Allergan Inc. This research was supported in part by Charles Dana Foundation, Pennsylvania Tobacco Settlement Biomedical Research Fund, and the Penn State University Brain Research Funds. Authors acknowledge the generous
help od Dr. D. Berg from Tubingen
0.000
0.100
0.200
0.300
0.400
V1 V2 V3
SNechognicity
(cm2)
Visit
Average SN Hyperechogenicity
Contralateral
Avg.
Ipsilateral
Avg.
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
0.5
IpsilateralHyperechogenicity(cm^2)
Subjects
Progression of Hyperechogenicity in the Less Affected Hemisphere
Visit 1
Visit 2
Visit 3
0
5
10
15
20
1 2 3 4
UPDRSScore
Visit
Average Overall UPDRS Score for
Motor Examination
0
2
4
6
8
10
12
14
16
18
20
22
24
0 350-450 451-550 551-650 651-750
NumberofSubjectsStillinstageI
Days Since Visit 1
Progression of EOPD Patients from Stage I to Stage II PD
A Kaplan-Meier Curve
As Determined by
Ipsilateral TCS
As Determined by
Affected Side MDS-
UPDRS
 There is a clear mismatch between changes seen on TCS and the
clinician’s ability to detect parkinsonism in the less affected side during
clinical evaluation despite careful and detailed examination and rigorous
application of MDS-UPDRS and a multitude of bedside maneuvers
designed to unmask clinical parkinsonism. This may be related to
incomplete washout of anti-PD medications after overnight withdrawal or
could be plastic changes induced by anti-PD treatments as noted in other
studies (e.g., ELLDOPA study). Surprisingly, even in unmedicated patients,
clinical detection of bilateral parkinsonism was not as quick as the
development of SN hyperechogenicity.
 TCS may be of value in clinical decision making for EOPD patients who
seek early surgical intervention. Presence of bilateral SN
hyperechogenicity in a patient previously shown to have only unilateral
hyperechogenicity, may be a better candidate for such intervention.
 In all patients in clinical Stage I disease, hyperechogenicity that met > 0.2 cm2 area by
planimetry was only found on the contralateral SN (N=21). At V2(350-479 days post
enrollment), 14 of these patients (66.66%) went onto develop >0.2 cm2 area of
hyperechogenicity in the ipsilateral SN that previously did not meet this criteria. The
other 7 patients progressed to meet the 0.2cm2 V3 (177-280 days post V1). V4 data
collection is ongoing.
 Side specific UPDRS on the unaffected side (resting tremor, alternate supination, opening and closing fist, finger
taps, foot tapping and UE and LE rigidity) was zero in all enrolled subjects at V1. As expected, overall mUPDRS
scores for all 21 patients gradually increased over time. However, the transition of Stage I to Stage II disease as
predicted by SN hyperechogenicity did not match up with careful mUPDRS examinations at V2 or beyond in
most cases. At V2, 2 patients clinically progressed from stage I to stage II. By V3, an additional 2 patients
progressed to stage II.
Results