Menu

 

The NASA Task Book
Advanced Search     

Project Title:  A Non-intrusive Ocular Monitoring Framework to Model Ocular Structure and Functional Changes due to Long-term Spaceflight Reduce
Images: icon  Fiscal Year: FY 2021 
Division: Human Research 
Research Discipline/Element:
HRP HHC:Human Health Countermeasures
Start Date: 08/27/2020  
End Date: 08/26/2022  
Task Last Updated: 06/27/2021 
Download report in PDF pdf
Principal Investigator/Affiliation:   Tavakkoli, Alireza  Ph.D. / University of Nevada, Reno 
Address:  Department of Computer Science and Engineering 
1664 N Virginia St (MS0171) 
Reno , NV 89557-0001 
Email: tavakkol@unr.edu 
Phone: 775-682-8426  
Congressional District:
Web:  
Organization Type: UNIVERSITY 
Organization Name: University of Nevada, Reno 
Joint Agency:  
Comments:  
Co-Investigator(s)
Affiliation: 
Webster, Michael  Ph.D. University of Nevada, Reno 
Key Personnel Changes / Previous PI: N/A
Project Information: Grant/Contract No. 80NSSC20K1831 
Responsible Center: NASA JSC 
Grant Monitor: Stenger, Michael  
Center Contact: 281-483-1311 
michael.b.stenger@nasa.gov 
Solicitation / Funding Source: 2019 HERO 80JSC019N0001-FLAGSHIP & OMNIBUS: Human Research Program Crew Health. Appendix A&B 
Grant/Contract No.: 80NSSC20K1831 
Project Type: GROUND 
Flight Program:  
TechPort: Yes 
No. of Post Docs:
No. of PhD Candidates:
No. of Master's Candidates:
No. of Bachelor's Candidates:
No. of PhD Degrees:
No. of Master's Degrees:
No. of Bachelor's Degrees:
Human Research Program Elements: (1) HHC:Human Health Countermeasures
Human Research Program Risks: (1) SANS:Risk of Spaceflight Associated Neuro-ocular Syndrome (IRP Rev I)
Human Research Program Gaps: (1) SANS-202:Determine if genetic/metabolic/anatomic dispositions and biomarkers, and sex differences have a contributing role in the development of ocular manifestations (IRP Rev L)
(2) SANS-301:Laboratory development of mechanical countermeasures (IRP Rev L)
Flight Assignment/Project Notes: NOTE: End date changed to 08/26/2022 per NSSC information. (Ed. 10/26/21)

Task Description: Unique neuro-ocular structural and functional changes affect a subset of astronauts who have completed prolonged spaceflight missions and due to its unique pathology, a new case definition was proposed and the condition was renamed Spaceflight Associated Neuro-ocular Syndrome (SANS). In this project we investigate two interconnected computational frameworks to develop a diagnostic system as well as a mapping mechanism to assist NASA scientists and clinical experts to more comprehensively study the SANS phenomenon and predict the risk of its development in prolonged spaceflight. Therefore, the first aim (Aim 1) of this project is to develop novel computational tools to establish mappings between the observed ocular structure and visual function, pre-, in-, and post-flight, in order to provide NASA scientists and clinicians with better means to investigate SANS etiology and its progression. The second aim (Aim 2) of this project is to integrate Contrast Sensitivity (CS), Visual Fields (VF), and our novel distortion assessment mechanism into a validated and compact diagnostic tool to better measure ocular function (SANS 301 : Laboratory development of mechanical countermeasures).

We will focus our efforts in each aim on a sub-set of functionalities that allow for the establishment of the interconnected computational framework enabling the pursuit of long-term research to predict the risk of development of SANS and monitor its progression.

Omnibus Aim 1: Structure-Function Mapping

Research Task-1.1: Design a novel mapping between Optical Coherence Tomography (OCT), Magnetic Resonance Imaging (MRI), Contrast Sensitivity (CS), and Visual Fields (VF) perimetry.

Research Task-1.2: Conduct studies on retrospective data from NASA Lifetime Surveillance of Astronaut Health (LSAH) and Life Sciences Data Archive (LSDA) on the three populations (astronauts, head-down-tilt bed rest, and idiopathic intracranial hypertension (IIH)) patient.

These findings will be significant in two ways:

(1) They will allow us to predict measures within a smaller sample set, if a larger analog sample set has known structure-function maps.

(2) They will enable us to design predictive mechanisms to study disease progression both in astronauts and in terrestrial analogs terrestrial analogs.

Expected Outcomes: (1.i) understanding how OCT/MRI correlates with VF, (1.ii) translational parametrization of mappings across cohorts, and (1.iii) ability to predict the risk of development of SANS and monitor its progression by utilizing the proposed mappings.

Omnibus Aim 2: Address SANS 301 Knowledge Gap

Research Task-2.1: Integrate VF and CS assessments into a VR-mediated framework.

Research Task-2.2: Validate VR-based VF/CS on the terrestrial analog populations.

Expected Outcomes: (2.i) a novel Virtual Reality (VR)-based VF/CS assessment and (2.ii) a compact diagnostic tool.

Research Impact/Earth Benefits: During the previous year of the project, our team has made contributions on the two aims as follows:

Aim 1- The first aim (Aim 1) of this project is to develop novel computational tools to establish mappings between the observed ocular structure and visual function, pre-, in-, and post-flight, in order to provide NASA scientists and clinicians with better means to investigate SANS etiology and its progression (SANS 1).

Contributions: 1- Design a novel mapping between OCT, MRI, CS, and VF. 2- Conduct studies on retrospective data from NASA Lifetime Surveillance of Astronaut Health (LSAH) and Life Sciences Data Archive (LSDA) on the three populations.

Technical Details: In order to establish a comprehensive mapping between different ophthalmic domains we started by designing a conditional generative adversarial network (GAN) to map across the publicly available data we had at our disposal, i.e., fluorescein angiography (FA) and fundus photographs. The GAN comprises of two generator modules and four discriminator modules to take fundus photographs and produce anatomically accurate FA images inferred from the fundus images.

Impact: We have shown novel deep architectures in ophthalmic applications could improve diagnostic accuracy, that attention maps can improve transferability of learned models across datasets, and deep architectures could effectively extract shared feature representations across ophthalmic image modalities to translate from one domain to another. These discoveries have paved the way for our team to tackle the main problem of mapping between the domain of ocular structure to the visual function.

Significance: (1) Understanding how ocular structure correlates with visual function. (2) Parametrization of mappings. (3) Predict the risk of SANS.

Aim 2- The second aim (Aim 2) of this project is to integrate CS, VF, and our novel distortion assessment mechanism into a validated and compact diagnostic tool to better measure ocular function (SANS 3).

Contributions: 1- Integrate VF/CS assessments into a VR-mediated framework. 2- Validate VR-based VF/CS on the terrestrial analog populations.

Technical Details: We present a methodology that comprises a calibration step, four different visual function tests that measure different aspects of user perception, and then a composite pipeline that simulates the modeled deficits for validation. In order to properly utilize the virtual assessment, the environment would need to be calibrated at the beginning of each session. Simple calibrations such as adjusting lens distance, interpupillary distance, and headset adjustments are done at the start. After these adjustments, the fixation and tracking capabilities of the eyes are tested, first binocularly and then monocularly. These performance metrics are saved alongside the user demography information. After the calibration phase, the user's visual assessment can commence. Visual acuity (VA), contrast sensitivity (CS), and visual distortions are assessed through a variety of procedures. For VA, binocular distant VA as well as dynamic VA is measured under mesopic (natural light) conditions. Instead of using images of conventional charts, we render individual characters in front of the user at predetermined distances and scale it based on user response. The results are reported in logMAR scale among others. The contrast sensitivity is measured using gabor patches as stimuli. In this test, the user gaze follows a gabor patch that alters its contrast and spatial frequency based on user performance. At the end, the contrast sensitivity expressed in logCS among other contrast sensitivity units. The amsler grid test is adapted to VR to measure the perceptual distortions in age-related macular degeneration (AMD) patients. At the start of the exam, the amsler grid is displayed infront of both eyes. While looking at a fixation point in grid, if the straight grid lines appear to be distorted the user emulates the metamorphopsia of the deficient eye on the healthy eye. This grid manipulation is modeled as a gaussian mixture of different scotoma parameters. The results are reported as the image of the altered amsler grid.

Impact: In addition, we have developed a new approach mediated by advances in virtual reality (VR) for better assessment of metamorphopsia to enable remote monitoring of the progression of AMD \cite{zaman2020mixed}. These findings in conjunction with the findings of Aim 1 motivate and inform the objectives of this project, by allowing our team to maintain a correspondence between how the ocular structural changes could impact visual function assessments.

Significance: (1) A novel VR-based VF/CS assessment. (2) A compact diagnostic tool.

Task Progress & Bibliography Information FY2021 
Task Progress: We have initiated the data request form from NASA shortly after the award notification was announced on August 14, 2020. On the same day the study was submitted to NASA Institutional Review Board (IRB) under protocol STUDY00000269. On September 22nd the Principal Investigator (PI) presented the data request to the LHSA Advisory Board. October 28, 2020 the NASA IRB approved the study protocol. On December 18, 2020 the University of Nevada Reno (UNR) Research Integrity office approved the NASA Reliance Acknowledgement document and the full IRB approved the project on January 21, 2021. The final data request signature was delivered to NASA on June 6th to complete the data request action and download the provided data from NASA LSAH/LSDA repositories.

We have shown novel deep architectures in ophthalmic applications could improve diagnostic accuracy, that attention maps can improve transferability of learned models across datasets, and deep architectures could effectively extract shared feature representations across ophthalmic image modalities to translate from one domain to another. These discoveries have paved the way for our team to tackle the main problem of mapping between the domain of ocular structure to the visual function.

In addition, we have developed a new approach mediated by advances in virtual reality (VR) for better assessment of metamorphopsia to enable remote monitoring of the progression of age-related macular degeneration (AMD). These findings in conjunction with the findings of Aim 1 motivate and inform the objectives of this project, by allowing our team to maintain a correspondence between how the ocular structural changes could impact visual function assessments.

As of the writing of this report, the retrospective data has not been received. However, we have utilized publicly available data for some preliminary validation of the work done so far. In addition to this limitation, the CoVID-19 pandemic has prevented our team from collecting prospective data from patient analog and control subjects. The publicly available data we have used in this year only included multiple modalities of ocular physiology. Therefore, the current models are fully capable of mapping between various ocular structure modalities. Despite this limitation, the models are designed without any specific restrictions on the domain of data (i.e., structure or function). Therefore, we anticipate that with the availability of additional modalities during the second year more comprehensive models can be trained to map across visual function and ocular structure domains.

Bibliography Type: Description: (Last Updated: 06/24/2022) 

Show Cumulative Bibliography Listing
 
Dissertations and Theses Zaman N. (Nasif Zaman) "EyeSightVR: An Immersive and Automated Tool for Comprehensive Assessment of Visual Function." University of Nevada, Reno, May 2021. , May-2021
Papers from Meeting Proceedings Kamran SA, Hossain KF, Tavakkoli A, Zuckerbrod SL, Sander KM, Baker SA. "RV-GAN: Segmenting Retinal Vascular Structure in Fundus Photographs using a Novel Multi-scale Generative Adversarial Network." 24th International Conference on Medical Image Computing and Computer Assisted (MICCAI) Intervention, Virtual, September 27-October 1, 2021.

Proceedings of the 24th International Conference on Medical Image Computing and Computer Assisted (MICCAI) Intervention, Virtual, September 27-October 1, 2021. In press, as of July 2021. , Jul-2021

Project Title:  A Non-intrusive Ocular Monitoring Framework to Model Ocular Structure and Functional Changes due to Long-term Spaceflight Reduce
Images: icon  Fiscal Year: FY 2020 
Division: Human Research 
Research Discipline/Element:
HRP HHC:Human Health Countermeasures
Start Date: 08/27/2020  
End Date: 08/26/2021  
Task Last Updated: 10/18/2020 
Download report in PDF pdf
Principal Investigator/Affiliation:   Tavakkoli, Alireza  Ph.D. / University of Nevada, Reno 
Address:  Department of Computer Science and Engineering 
1664 N Virginia St (MS0171) 
Reno , NV 89557-0001 
Email: tavakkol@unr.edu 
Phone: 775-682-8426  
Congressional District:
Web:  
Organization Type: UNIVERSITY 
Organization Name: University of Nevada, Reno 
Joint Agency:  
Comments:  
Co-Investigator(s)
Affiliation: 
Webster, Michael  Ph.D. University of Nevada, Reno 
Project Information: Grant/Contract No. 80NSSC20K1831 
Responsible Center: NASA JSC 
Grant Monitor: Grant-Technical-Officer, JSC-SA  
Center Contact: 281.244.8942 
jsc-sa-grant-technical-officer@mail.nasa.gov 
Solicitation / Funding Source: 2019 HERO 80JSC019N0001-FLAGSHIP & OMNIBUS: Human Research Program Crew Health. Appendix A&B 
Grant/Contract No.: 80NSSC20K1831 
Project Type: GROUND 
Flight Program:  
TechPort: Yes 
No. of Post Docs:  
No. of PhD Candidates:  
No. of Master's Candidates:  
No. of Bachelor's Candidates:  
No. of PhD Degrees:  
No. of Master's Degrees:  
No. of Bachelor's Degrees:  
Human Research Program Elements: (1) HHC:Human Health Countermeasures
Human Research Program Risks: (1) SANS:Risk of Spaceflight Associated Neuro-ocular Syndrome (IRP Rev I)
Human Research Program Gaps: (1) SANS-202:Determine if genetic/metabolic/anatomic dispositions and biomarkers, and sex differences have a contributing role in the development of ocular manifestations (IRP Rev L)
(2) SANS-301:Laboratory development of mechanical countermeasures (IRP Rev L)
Task Description: Unique neuro-ocular structural and functional changes affect a subset of astronauts who have completed prolonged spaceflight missions and due to its unique pathology, a new case definition was proposed and the condition was renamed Spaceflight Associated Neuro-ocular Syndrome (SANS). In this project we investigate two interconnected computational frameworks to develop a diagnostic system as well as a mapping mechanism to assist NASA scientists and clinical experts to more comprehensively study the SANS phenomenon and predict the risk of its development in prolonged spaceflight. Therefore, the first aim (Aim 1) of this project is to develop novel computational tools to establish mappings between the observed ocular structure and visual function, pre-, in-, and post-flight, in order to provide NASA scientists and clinicians with better means to investigate SANS etiology and its progression. The second aim (Aim 2) of this project is to integrate Contrast Sensitivity (CS), Visual Fields (VF), and our novel distortion assessment mechanism into a validated and compact diagnostic tool to better measure ocular function (SANS 301 : Laboratory development of mechanical countermeasures).

We will focus our efforts in each aim on a sub-set of functionalities that allow for the establishment of the interconnected computational framework enabling the pursuit of long-term research to predict the risk of development of SANS and monitor its progression.

Omnibus Aim 1: Structure-Function Mapping

Research Task-1.1: Design a novel mapping between Optical Coherence Tomography (OCT), Magnetic Resonance Imaging (MRI), Contrast Sensitivity (CS), and Visual Fields (VF) perimetry.

Research Task-1.2: Conduct studies on retrospective data from NASA Lifetime Surveillance of Astronaut Health (LSAH) and Life Sciences Data Archive (LSDA) on the three populations (astronauts, head-down-tilt bed rest, and idiopathic intracranial hypertension (IIH)) patient.

These findings will be significant in two ways:

(1) They will allow us to predict measures within a smaller sample set, if a larger analog sample set has known structure-function maps.

(2) They will enable us to design predictive mechanisms to study disease progression both in astronauts and in terrestrial analogs terrestrial analogs.

Expected Outcomes: (1.i) understanding how OCT/MRI correlates with VF, (1.ii) translational parametrization of mappings across cohorts, and (1.iii) ability to predict the risk of development of SANS and monitor its progression by utilizing the proposed mappings.

Omnibus Aim 2: Address SANS 301 Knowledge Gap

Research Task-2.1: Integrate VF and CS assessments into a VR-mediated framework.

Research Task-2.2: Validate VR-based VF/CS on the terrestrial analog populations.

Expected Outcomes: (2.i) a novel Virtual Reality (VR)-based VF/CS assessment and (2.ii) a compact diagnostic tool.

Research Impact/Earth Benefits:

Task Progress & Bibliography Information FY2020 
Task Progress: New project for FY2020.

Bibliography Type: Description: (Last Updated: 06/24/2022) 

Show Cumulative Bibliography Listing
 
 None in FY 2020