ArticleAnnals of Indian Academy of Neurology2026
Interpeduncular Angle: A Possible Marker to Differentiate Atypical Parkinsonism from Idiopathic Parkinson's Disease.
Article in Annals of Indian Academy of Neurology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
0 citing papers in PubMed.
No citing paper in PubMed yet.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
10 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Atypical parkinsonian disorders (APD), such as progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal syndrome (CBS), and Lewy body dementia (LBD) are frequently misdiagnosed, commonly as Parkinson's disease (PD). The study aims to assess the utility of the interpeduncular angle (IPA) in distinguishing APD from PD across age ranges. This retrospective study was conducted with 225 patients (75 with APD, 75 with PD, and 75 healthy controls). Patients were categorized into three age groups: (51-60, 61-70, and 71-80 years). Two independent raters measured the IPA from T1-weighted axial brain magnetic resonance images (MRIs) at a level below the mammillary bodies using standardized measurement techniques. The APD group included 51 (68%) with PSP, 16 (21.33%) with MSA, 5 (6.67%) with LBD, and 3 (4%) with CBS. Bland-Altman analysis for angle measurement suggested good to excellent agreement between raters ( P < 0.001). IPA measurements among the different diagnostic groups showed that PSP was higher than controls ( P < 0.001) and PD ( P < 0.001), and MSA was higher than controls ( P < 0.001) and PD ( P = 0.003). There was no significant association between IPA and age in the APD phenotypes. With increasing age, the significance between APD and IPD groups decreased ( P < 0.001 in 51-60 years to P = 0.686 in 71-80 years). Receiver Operating Characteristic (ROC) analysis revealed increasing IPA thresholds for PSP versus PD (67.66° in 51-60 years to 75.71° in 71-80 years). IPA is not reliable in differentiating APD, particularly PSP and MSA, from PD and controls.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.