Use of a smartphone camera to assess pupil response to light in neurocritical care – comparison with pen torch

ISRCTN	ISRCTN53630869
DOI	https://doi.org/10.1186/ISRCTN53630869
ClinicalTrials.gov (NCT)	Nil known
Clinical Trials Information System (CTIS)	Nil known
Integrated Research Application System (IRAS)	324539
Protocol serial number	IRAS 324539
Sponsor	Solvemed Inc.
Funder	Solvemed Inc.

Submission date: 23/02/2023
Registration date: 20/04/2023
Last edited: 20/04/2023

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Other

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Background and study aims
This study is designed to compare the accuracy of measuring eye pupil size. It will compare the current standard of care, which is a pentorch and subjective assessment by a bedside nurse, to a new smartphone application using the camera and light of the phone to measure pupil size and responsiveness.

Who can participate?
Patients admitted to a specialist neurocritical care unit

What does the study involve?
Participants will have their pupils assessed by both methods hourly (which is standard) for a maximum of 10 days, during the day only. Not measuring at night provides respite for the patient (they will still have pentorch assessments) and reduces research staffing resources.

What are the possible benefits and risks of participating?
The interventions are non-invasive and as such there are no risks to participants. The proposed benefit is earlier identification of changes in pupil response, both in terms of improvement and deterioration.

Where is the study run from?
John Radcliffe Hospital (UK)

When is the study starting and how long is it expected to run for?
October 2022 to April 2023

Who is funding the study?
Solvemed Inc. (UK)

Who is the main contact?
Dr Simon Raby, simon.raby@ouh.nhs.uk

Contact information

Dr Simon Raby
Principal investigator

Neurocritical Care
John Radcliffe Hospital
Headley Way
Headington
Oxford
OX3 9DU
United Kingdom

ORCID ID	0000-0003-4886-9795
Phone	+44 (0)1865741166
Email	simon.raby@ouh.nhs.uk

Study information

Primary study design	Interventional
Study design	Single-centre non-randomized trial
Secondary study design	Non randomised study
Study type	Participant information sheet
Scientific title	Smartphone Pupillometry in Neurocritical Care - Comparison against PenTorch: the SPIN_CAT trial
Study acronym	SPIN-CAT
Study objectives	Smartphone pupillometry is more accurate than pentorch assessment of pupil responsiveness in neurocritical care patients.
Ethics approval(s)	Approval pending, South Central - Oxford C REC
Health condition(s) or problem(s) studied	Critically ill patients admitted to neurocritical care
Intervention	Patients will have pupillary assessments made by pentorch and smartphone pupillometry. Pentorch is routine and the smartphone application is the additional intervention. Each intervention will be performed hourly during the day shift, for a maximum of 10 days per patient. Pupil traces will be processed by Solvemed to generate two indices per eye: baseline pupil diameter (millimetres), and pupil reactivity (binary – responsive or non-responsive). Measurement reliability for pentorch and Solvemed app (baseline diameter) will be computed independently, to give an r-squared statistic for each. The reliabilities will be compared using a Fisher-transformed Z-test. The validity of the app will be established by the correlation of the pentorch and app measures. The primary outcome is that the app offers improved reliability. To gauge efficiency, questionnaires to nursing staff will be analysed using qualitative nonparametric statistics.
Intervention type	Device
Phase	Phase III
Drug / device / biological / vaccine name(s)	Solvemed Neurapeek
Primary outcome measure(s)	Pupil diameter (millimetres) and pupil reactivity (binary – responsive or non-responsive) measured using the two modalities (pentorch and Solvemed smartphone application), performed hourly during the day shift, for a maximum of 10 days per patient
Key secondary outcome measure(s)	There are no secondary outcome measures
Completion date	01/04/2023

Eligibility

Participant type(s)	Patient
Age group	Adult
Sex	All
Target sample size at registration	20
Key inclusion criteria	Any patient admitted to neurocritical care
Key exclusion criteria	Pupillary assessment not possible due to ocular pathology
Date of first enrolment	01/04/2023
Date of final enrolment	01/04/2024

Locations

Countries of recruitment

United Kingdom
England

Study participating centre

Oxford Radcliffe Hospital NHS Trust

The John Radcliffe
Headley Way
Headington
Oxford
OX3 9DU
United Kingdom

Results and Publications

Individual participant data (IPD) Intention to share	Yes
IPD sharing plan summary	Stored in non-publicly available repository
IPD sharing plan	The datasets generated during and/or analysed during the current study will be stored in a non-publicly available repository: Following video capture, the video is uploaded onto the company-owned Amazon S3 server storage space (the cloud storage), where the captured videos and any associated data are stored in Amazon SQL databases. To ensure the stored data is secure, company applies an industry-standard Hypertext Transfer Protocol Secure (HTTPS) encryption protocol for all traffic between its smartphones and AWS servers. In addition, company applies suitable company-level policies regarding the access levels and procedures regarding every Amazon AWS component, using appropriate Amazon roles and Amazon policies.

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes
Protocol file	version 1.0	03/08/2022	07/03/2023	No	No

Additional files

43271_PROTOCOL_V1.0_03Aug22.pdf: Protocol file

Editorial Notes

20/04/2023: Trial's existence confirmed by Solvemed Inc.