Dry EyeNCT04648085
Effect of Trigeminal Nerve Stimulation on Corneal Nerves and Chronic Ocular Pain
A study testing Trigeminal Nerve Stimulation in people with Dry Eye and Neuropathic Pain, run by Instituto de Oftalmología Fundación Conde de Valenciana at 1 site in Mexico.
Trial summary
Individuals with dry eye tend to present with ocular pain which persists despite the use of topical treatment. This could be secondary to somatosensory impairment attributable to neuropathic pain. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Dry Eye, Neuropathic Pain, Eye Pain
- What is being tested?
- Trigeminal Nerve Stimulation
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 7 participants
- Where
- 1 siteMexico
- Study dates
- 3 Feb 2021to 10 Dec 2021
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Individuals with dry eye, Ocular pain for more than 3 months, Contact lens users, Individuals using topical treatment and/or systemic medication for dry eye syndrome, Individuals with history of photo-ablative ocular surgery (Laser-assisted in situ keratomileusis (LASIK) , Photorefractive keratectomy (PRK), Small incision lenticule extraction(SMILE), Individuals with history of autoimmune disease (Lupus, Rheumatoid Arthritis, Sjögrens),
Who cannot join
- Individuals with pacemakers or implantable defibrillators, Individuals with diagnosis of epilepsy, History of facial trauma one month prior to recruitment, Acute facial pain with unknown etiology, History of ocular surgery one month prior to recruitment, Trigeminal neuralgia, Active Herpes Zoster Ophthalmicus,
Trial locations and contacts
1 site in 1 country.
Mexico1 site
Instituto de Oftalmología Conde de Valenciana
Mexico City, Mexico City, 06800
About this study
Official title: Effect of Trigeminal Nerve Stimulation on Subbasal Corneal Nerve Plexus Density and Chronic Ocular Pain in Patients With Dry Eye
Individuals with dry eye tend to present with ocular pain which persists despite the use of topical treatment. This could be secondary to somatosensory impairment attributable to neuropathic pain. The purpose of this study is to evaluate the effect of trigeminal nerve stimulation (TNS) on corneal nerves and chronic ocular pain in patients with dry eye.
Read the detailed description
Dry eye is a multifactorial disease that produces a variety of clinical manifestations including, dryness, pain, blurred vision, and sensitivity to light or wind. Differences have been noted between the symptoms reported and the signs presented on physical examination, which suggests the involvement of somatosensory impairment. Ocular neuropathic pain is characterized by burning pain, hyperalgesia, photophobia, and sensitivity to wind. There are common physiopathological pathways, suggesting that corneal nerve sensitization contributes to the development of dry eye symptoms. Furthermore, in vivo confocal microscopy has reported a decrease in the density of the subbasal plexus in patients with a neuropathic component and dry eye, suggesting that they are not mutually exclusive conditions. Various topical treatments, as well as systemic medications are known to manage eye pain and dry eye. However, in some cases, individuals have been refractory to them, enhancing the importance of research in adjuvant therapies such as TNS.
This research protocol evaluates the effect of transcutaneous stimulation on corneal subbasal plexus density and chronic eye pain in patients with dry eye. A complete dry eye examination will be performed, including completion of Ocular Surface Disease Index (OSDI) and Dry Eye Questionnaire-5 (DEQ-5). Subbasal nerves density will be measured by confocal microscopy before and after receiving treatment with TNS. In addition, monthly monitoring of the intensity of ocular pain (with a numerical scale of 0-10) will be maintained. The intensity and severity of the clinical variables will be compared before and after receiving the treatment with a paired t-test considering a value of p<0.05 as statistically significant.
- Conditions
- Dry Eye, Neuropathic Pain, Eye Pain
- Being tested
- Trigeminal Nerve Stimulation
- Keywords
- Transcutaneous Electric Stimulation, In vivo Confocal Microscopy, Subbasal Corneal Nerve Plexus, Dry Eye, Neuropathic Pain
- Medical subject headings
- Dry Eye Syndromes, Neuralgia, Eye Pain
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Trigeminal Nerve StimulationDevice
Applied to to the forehead using a self-adhesive electrode positioned bilaterally over the upper branches of the trigeminal nerve.The device generates electrical impulses allowing to stimulate the trigeminal nerve.
| Study group | Role | What they receive |
|---|---|---|
| Pre and Post Treatment with Trigeminal Nerve Stimulation (TNS) | Experimental | Individuals will receive treatment with trigeminal nerve stimulation for 20 minutes at a frequency of 100 Hertz (Hz). Ocular pain intensity will be recorded prior and after the use of therapy. Receives: Device: Trigeminal Nerve Stimulation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Identify the effect of trigeminal nerve stimulation on chronic eye pain in patients with dry eye.
Eye pain will be evaluated prior to the use of trigeminal nerve stimulation using a numeric pain scale ranging from 0-10, "0" indicating no pain and "10" indicating the most severe pain imaginable.
Pain will be evaluated posterior to therapy with trigeminal nerve stimulation with the same scale during monthly follow up.
Measured: From three-six months
Identify the effect of trigeminal nerve stimulation on subbasal corneal nerve plexus density in patients with dry eye.
Initial subbasal corneal nerve plexus density will be measured prior to therapy with with in vivo confocal microscopy.
Density measurements will be repeated every two months with in vivo confocal microscopy posterior to trigeminal nerve stimulation use.
Measured: 2 months- 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Dec 2020
- Study start3 Feb 2021
- Primary completion10 Dec 2021
- Study completion10 Dec 2021
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (22)Papers the sponsor has linked to this study.
- Other trials for Dry EyeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Prospective, open, single-arm pilot study without randomization.
- Masking
- None (open label)
- Enrolment
- 7 participants (actual)
Sponsor and investigators
- Lead sponsor
- Instituto de Oftalmología Fundación Conde de Valenciana
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Simran Mangwani Mordani, MD, Principal investigator, Instituto de Oftalmología Conde de Valenciana
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04648085
- Sponsor's protocol ID
- CI-006-2020
- Status last verified
- Jan 2022
- First submitted
- 21 Nov 2020
- Last updated
- 18 Jan 2022
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- Yes
- Individual data sharing
- Undecided
Publications
Galor A, Moein HR, Lee C, Rodriguez A, Felix ER, Sarantopoulos KD, Levitt RC. Neuropathic pain and dry eye. Ocul Surf. 2018 Jan;16(1):31-44. doi: 10.1016/j.jtos.2017.10.001. Epub 2017 Oct 12.
PubMed 29031645Craig JP, Nelson JD, Azar DT, Belmonte C, Bron AJ, Chauhan SK, de Paiva CS, Gomes JAP, Hammitt KM, Jones L, Nichols JJ, Nichols KK, Novack GD, Stapleton FJ, Willcox MDP, Wolffsohn JS, Sullivan DA. TFOS DEWS II Report Executive Summary. Ocul Surf. 2017 Oct;15(4):802-812. doi: 10.1016/j.jtos.2017.08.003. Epub 2017 Aug 8.
PubMed 28797892De Paiva CS, Corrales RM, Villarreal AL, Farley WJ, Li DQ, Stern ME, Pflugfelder SC. Corticosteroid and doxycycline suppress MMP-9 and inflammatory cytokine expression, MAPK activation in the corneal epithelium in experimental dry eye. Exp Eye Res. 2006 Sep;83(3):526-35. doi: 10.1016/j.exer.2006.02.004. Epub 2006 Apr 27.
PubMed 16643899Karson CN, Burns RS, LeWitt PA, Foster NL, Newman RP. Blink rates and disorders of movement. Neurology. 1984 May;34(5):677-8. doi: 10.1212/wnl.34.5.677.
PubMed 6231489Dworkin RH, O'Connor AB, Kent J, Mackey SC, Raja SN, Stacey BR, Levy RM, Backonja M, Baron R, Harke H, Loeser JD, Treede RD, Turk DC, Wells CD. Interventional management of neuropathic pain: NeuPSIG recommendations. Pain. 2013 Nov;154(11):2249-2261. doi: 10.1016/j.pain.2013.06.004. Epub 2013 Jun 6.
PubMed 23748119Kalangara JP, Galor A, Levitt RC, Covington DB, McManus KT, Sarantopoulos CD, Felix ER. Characteristics of Ocular Pain Complaints in Patients With Idiopathic Dry Eye Symptoms. Eye Contact Lens. 2017 May;43(3):192-198. doi: 10.1097/ICL.0000000000000249.
PubMed 26925537Farhangi M, Feuer W, Galor A, Bouhassira D, Levitt RC, Sarantopoulos CD, Felix ER. Modification of the Neuropathic Pain Symptom Inventory for use in eye pain (NPSI-Eye). Pain. 2019 Jul;160(7):1541-1550. doi: 10.1097/j.pain.0000000000001552.
PubMed 30883524Woolf CJ, Salter MW. Neuronal plasticity: increasing the gain in pain. Science. 2000 Jun 9;288(5472):1765-9. doi: 10.1126/science.288.5472.1765.
PubMed 10846153Crane AM, Feuer W, Felix ER, Levitt RC, McClellan AL, Sarantopoulos KD, Galor A. Evidence of central sensitisation in those with dry eye symptoms and neuropathic-like ocular pain complaints: incomplete response to topical anaesthesia and generalised heightened sensitivity to evoked pain. Br J Ophthalmol. 2017 Sep;101(9):1238-1243. doi: 10.1136/bjophthalmol-2016-309658. Epub 2017 Jan 18.
PubMed 28100479Matsumoto Y, Ibrahim OMA. Application of In Vivo Confocal Microscopy in Dry Eye Disease. Invest Ophthalmol Vis Sci. 2018 Nov 1;59(14):DES41-DES47. doi: 10.1167/iovs.17-23602.
PubMed 30481805Tavakoli M, Hossain P, Malik RA. Clinical applications of corneal confocal microscopy. Clin Ophthalmol. 2008 Jun;2(2):435-45. doi: 10.2147/opth.s1490.
PubMed 19668734Zhang M, Chen J, Luo L, Xiao Q, Sun M, Liu Z. Altered corneal nerves in aqueous tear deficiency viewed by in vivo confocal microscopy. Cornea. 2005 Oct;24(7):818-24. doi: 10.1097/01.ico.0000154402.01710.95.
PubMed 16160498Alhatem A, Cavalcanti B, Hamrah P. In vivo confocal microscopy in dry eye disease and related conditions. Semin Ophthalmol. 2012 Sep-Nov;27(5-6):138-48. doi: 10.3109/08820538.2012.711416.
PubMed 23163268Kinard KI, Smith AG, Singleton JR, Lessard MK, Katz BJ, Warner JE, Crum AV, Mifflin MD, Brennan KC, Digre KB. Chronic migraine is associated with reduced corneal nerve fiber density and symptoms of dry eye. Headache. 2015 Apr;55(4):543-9. doi: 10.1111/head.12547. Epub 2015 Mar 31.
PubMed 25828778Aggarwal S, Kheirkhah A, Cavalcanti BM, Cruzat A, Colon C, Brown E, Borsook D, Pruss H, Hamrah P. Autologous Serum Tears for Treatment of Photoallodynia in Patients with Corneal Neuropathy: Efficacy and Evaluation with In Vivo Confocal Microscopy. Ocul Surf. 2015 Jul;13(3):250-62. doi: 10.1016/j.jtos.2015.01.005. Epub 2015 Feb 20.
PubMed 26045233
Study at a glance
From the registry record, last updated by the sponsor on 18 Jan 2022. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Trigeminal Nerve Stimulation on Subbasal Corneal Nerve Plexus Density and Chronic Ocular Pain in Patients With Dry Eye
- ClinicalTrials.gov ID
- NCT04648085
- Acronym / sponsor ID
- CI-006-2020
- Conditions
- Dry Eye, Neuropathic Pain, Eye Pain
- Keywords
- Transcutaneous Electric Stimulation, In vivo Confocal Microscopy, Subbasal Corneal Nerve Plexus, Dry Eye, Neuropathic Pain
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 7 participants (actual)
- Lead sponsor
- Instituto de Oftalmología Fundación Conde de ValencianaUniversity, hospital or other
- Study start
- 3 Feb 2021 (actual)
- Primary completion
- 10 Dec 2021 (actual)
- Study completion
- 10 Dec 2021 (actual)
- First posted
- 1 Dec 2020 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Individuals with dry eye tend to present with ocular pain which persists despite the use of topical treatment. This could be secondary to somatosensory impairment attributable to neuropathic pain. The purpose of this study is to evaluate the effect of trigeminal nerve stimulation (TNS) on corneal nerves and chronic ocular pain in patients with dry eye.
Detailed description
Dry eye is a multifactorial disease that produces a variety of clinical manifestations including, dryness, pain, blurred vision, and sensitivity to light or wind. Differences have been noted between the symptoms reported and the signs presented on physical examination, which suggests the involvement of somatosensory impairment. Ocular neuropathic pain is characterized by burning pain, hyperalgesia, photophobia, and sensitivity to wind. There are common physiopathological pathways, suggesting that corneal nerve sensitization contributes to the development of dry eye symptoms. Furthermore, in vivo confocal microscopy has reported a decrease in the density of the subbasal plexus in patients with a neuropathic component and dry eye, suggesting that they are not mutually exclusive conditions. Various topical treatments, as well as systemic medications are known to manage eye pain and dry eye. However, in some cases, individuals have been refractory to them, enhancing the importance of research in adjuvant therapies such as TNS.
This research protocol evaluates the effect of transcutaneous stimulation on corneal subbasal plexus density and chronic eye pain in patients with dry eye. A complete dry eye examination will be performed, including completion of Ocular Surface Disease Index (OSDI) and Dry Eye Questionnaire-5 (DEQ-5). Subbasal nerves density will be measured by confocal microscopy before and after receiving treatment with TNS. In addition, monthly monitoring of the intensity of ocular pain (with a numerical scale of 0-10) will be maintained. The intensity and severity of the clinical variables will be compared before and after receiving the treatment with a paired t-test considering a value of p<0.05 as statistically significant.
Study design
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Prospective, open, single-arm pilot study without randomization.
| Arm | Type | Receives |
|---|---|---|
| Pre and Post Treatment with Trigeminal Nerve Stimulation (TNS) | Experimental | Device: Trigeminal Nerve StimulationIndividuals will receive treatment with trigeminal nerve stimulation for 20 minutes at a frequency of 100 Hertz (Hz). Ocular pain intensity will be recorded prior and after the use of therapy. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- Individuals with dry eye, Ocular pain for more than 3 months, Contact lens users, Individuals using topical treatment and/or systemic medication for dry eye syndrome, Individuals with history of photo-ablative ocular surgery (Laser-assisted in situ keratomileusis (LASIK) , Photorefractive keratectomy (PRK), Small incision lenticule extraction(SMILE), Individuals with history of autoimmune disease (Lupus, Rheumatoid Arthritis, Sjögrens),
Key exclusion criteria (1 listed)
- Individuals with pacemakers or implantable defibrillators, Individuals with diagnosis of epilepsy, History of facial trauma one month prior to recruitment, Acute facial pain with unknown etiology, History of ocular surgery one month prior to recruitment, Trigeminal neuralgia, Active Herpes Zoster Ophthalmicus,
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Trigeminal Nerve StimulationApplied to to the forehead using a self-adhesive electrode positioned bilaterally over the upper branches of the trigeminal nerve.The device generates electrical impulses allowing to stimulate the trigeminal nerve. | Device | Pre and Post Treatment with Trigeminal Nerve Stimulation (TNS) |
Primary outcome
Identify the effect of trigeminal nerve stimulation on chronic eye pain in patients with dry eye.
Time frame: From three-six months
Eye pain will be evaluated prior to the use of trigeminal nerve stimulation using a numeric pain scale ranging from 0-10, "0" indicating no pain and "10" indicating the most severe pain imaginable. Pain will be evaluated posterior to therapy with trigeminal nerve stimulation with the same scale during monthly follow up.
Identify the effect of trigeminal nerve stimulation on subbasal corneal nerve plexus density in patients with dry eye.
Time frame: 2 months- 6 months
Initial subbasal corneal nerve plexus density will be measured prior to therapy with with in vivo confocal microscopy. Density measurements will be repeated every two months with in vivo confocal microscopy posterior to trigeminal nerve stimulation use.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 18 Jan 2022.
- Background: PubMed 29031645Galor A, Moein HR, Lee C, Rodriguez A, Felix ER, Sarantopoulos KD, Levitt RC. Neuropathic pain and dry eye. Ocul Surf. 2018 Jan;16(1):31-44. doi: 10.1016/j.jtos.2017.10.001. Epub 2017 Oct 12.
- Background: PubMed 28797892Craig JP, Nelson JD, Azar DT, Belmonte C, Bron AJ, Chauhan SK, de Paiva CS, Gomes JAP, Hammitt KM, Jones L, Nichols JJ, Nichols KK, Novack GD, Stapleton FJ, Willcox MDP, Wolffsohn JS, Sullivan DA. TFOS DEWS II Report Executive Summary. Ocul Surf. 2017 Oct;15(4):802-812. doi: 10.1016/j.jtos.2017.08.003. Epub 2017 Aug 8.
- Background: PubMed 16643899De Paiva CS, Corrales RM, Villarreal AL, Farley WJ, Li DQ, Stern ME, Pflugfelder SC. Corticosteroid and doxycycline suppress MMP-9 and inflammatory cytokine expression, MAPK activation in the corneal epithelium in experimental dry eye. Exp Eye Res. 2006 Sep;83(3):526-35. doi: 10.1016/j.exer.2006.02.004. Epub 2006 Apr 27.
- Background: PubMed 6231489Karson CN, Burns RS, LeWitt PA, Foster NL, Newman RP. Blink rates and disorders of movement. Neurology. 1984 May;34(5):677-8. doi: 10.1212/wnl.34.5.677.
- Background: PubMed 23748119Dworkin RH, O'Connor AB, Kent J, Mackey SC, Raja SN, Stacey BR, Levy RM, Backonja M, Baron R, Harke H, Loeser JD, Treede RD, Turk DC, Wells CD. Interventional management of neuropathic pain: NeuPSIG recommendations. Pain. 2013 Nov;154(11):2249-2261. doi: 10.1016/j.pain.2013.06.004. Epub 2013 Jun 6.
- Background: PubMed 26925537Kalangara JP, Galor A, Levitt RC, Covington DB, McManus KT, Sarantopoulos CD, Felix ER. Characteristics of Ocular Pain Complaints in Patients With Idiopathic Dry Eye Symptoms. Eye Contact Lens. 2017 May;43(3):192-198. doi: 10.1097/ICL.0000000000000249.
- Background: PubMed 30883524Farhangi M, Feuer W, Galor A, Bouhassira D, Levitt RC, Sarantopoulos CD, Felix ER. Modification of the Neuropathic Pain Symptom Inventory for use in eye pain (NPSI-Eye). Pain. 2019 Jul;160(7):1541-1550. doi: 10.1097/j.pain.0000000000001552.
- Background: PubMed 10846153Woolf CJ, Salter MW. Neuronal plasticity: increasing the gain in pain. Science. 2000 Jun 9;288(5472):1765-9. doi: 10.1126/science.288.5472.1765.
- Background: PubMed 28100479Crane AM, Feuer W, Felix ER, Levitt RC, McClellan AL, Sarantopoulos KD, Galor A. Evidence of central sensitisation in those with dry eye symptoms and neuropathic-like ocular pain complaints: incomplete response to topical anaesthesia and generalised heightened sensitivity to evoked pain. Br J Ophthalmol. 2017 Sep;101(9):1238-1243. doi: 10.1136/bjophthalmol-2016-309658. Epub 2017 Jan 18.
- Background: PubMed 30481805Matsumoto Y, Ibrahim OMA. Application of In Vivo Confocal Microscopy in Dry Eye Disease. Invest Ophthalmol Vis Sci. 2018 Nov 1;59(14):DES41-DES47. doi: 10.1167/iovs.17-23602.
- Background: PubMed 19668734Tavakoli M, Hossain P, Malik RA. Clinical applications of corneal confocal microscopy. Clin Ophthalmol. 2008 Jun;2(2):435-45. doi: 10.2147/opth.s1490.
- Background: PubMed 16160498Zhang M, Chen J, Luo L, Xiao Q, Sun M, Liu Z. Altered corneal nerves in aqueous tear deficiency viewed by in vivo confocal microscopy. Cornea. 2005 Oct;24(7):818-24. doi: 10.1097/01.ico.0000154402.01710.95.
- Individual participant dataSharing planned: Undecided
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Simran Mangwani Mordani, MD principal investigator
Instituto de Oftalmología Conde de Valenciana
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Trigeminal Nerve Stimulation in people with Dry Eye and Neuropathic Pain, run by Instituto de Oftalmología Fundación Conde de Valenciana at 1 site in Mexico.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 18 Jan 2022. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Mexico. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Identify the effect of trigeminal nerve stimulation on chronic eye pain in patients with dry eye. (time frame: From three-six months). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT04648085, which also lists 22 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Jan 2022.