Patient Comfort Using Green vs. Yellow Pan Retinal Photocoagulation

Proliferative Diabetic Retinopathy - High Risk Clinical Trial

Official title:

Patient Comfort Using Green (532 nm) Versus Yellow (577 nm) Laser Indirect Ophthalmoscopy Panretinal Photocoagulation for Proliferative Diabetic Retinopathy

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02995629
• Other study ID #: 16-560
• Status: Completed
• Phase: N/A
• First received: December 5, 2016
• Last updated: December 13, 2016
• Start date: March 2016
• Est. completion date: October 2016

Study information

• Verified date: December 2016
• Source: Wills Eye
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Food and Drug Administration
• Study type: Interventional

Clinical Trial Summary

Our aim is to compare patient comfort when using the 532 nanometer (green) wavelength laser to the 577 nanometer (yellow) wavelength laser during pan retinal photocoagulation to treat patients with diabetic retinopathy. Secondary outcome measures will be power (mW) required to achieve gray-white retinal burns and duration of treatment.

Description:

As demonstrated in the Diabetic Retinopathy Study (DRS), panretinal photocoagulation (PRP) reduces the risk of severe vision loss in patients with proliferative diabetic retinopathy. The DRS recommended that PRP treatment consist of 1,200 - 1,600 laser burns 500 µm in size, one half to one burn width apart, applied to the peripheral retina in a scatter fashion. Most patients who undergo PRP experience discomfort/pain during the procedure. Once present, pain can affect the number and quality of burns delivered and can indirectly increase the number of sessions required to complete the therapy.This may in turn adversely affect patient compliance. Although retrobulbar and peribulbar blocks can provide adequate anesthesia for PRP, these anesthetic methods carry rare but serious risks such as retrobulbar hemorrhage. Previous studies have explored other ways to reduce discomfort related to PRP, including optimization of laser settings, oral and topical analgesics, subconjunctival anesthesia, and even acupuncture.

Currently, green lasers (521 - 532 nm wavelength) are most commonly utilized for performing PRP in clinical practice. Yellow lasers (577 nm wavelength) have been of recent interest in treating diabetic macular edema with micropulse subthreshold grid photocoagulation, but have not been extensively studied in PRP for diabetic retinopathy. Compared to shorter wavelength laser, yellow laser comports high transmission through dense ocular media and less light scattering than shorter wavelengths which minimizes spot size and reduces thermal spread. The limited literature comparing green and yellow laser for PRP in diabetic retinopathy has shown that yellow laser requires less power to achieve a retinal burn. In theory this should translate into a reduction in perceived pain experienced during PRP, however a comparison of green and yellow lasers in this regard has not yet been directly examined and quantified.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 40
• Est. completion date: October 2016
• Est. primary completion date: October 2016
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• patient of Wills Eye Hospital Retina Service and/or Mid Atlantic Retina

• volunteer patients age 18 years and older.

• healthy enough to participate in the study.

• willing and able to consent to participation in the study.

• diagnosis of PDR with HRC based on clinical criteria outlined by the DRS.

Exclusion Criteria:

• patient less than 18 years of age

• institutionalized patient

• prisoner

• significant media opacity obscuring a view of the superior retina

• history of intra-ocular surgery except cataract surgery

• history of PRP laser within the last 30 days

Study Design

Allocation: Randomized, Intervention Model: Crossover Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Diabetic Retinopathy
• Proliferative Diabetic Retinopathy - High Risk
• Retinal Diseases

Intervention

Procedure:
• laser indirect ophthalmoscopy pan retinal photocoagulation
Prior to procedure, eligible patient is dilated and a topical anesthesia is administered 3 to 5 minutes prior to treatment initiation Treatment duration is fixed at 50 minutes and power is titrated until moderate gray-white burns are achieved, avoiding long ciliary nerves Target treatment of 250 spots Only one eye per eligible patient randomized with regard to whether green or yellow laser utilized first After treatment,pain assessment conducted:spot count, laser parameters and treatment duration recorded for each respective laser wavelength

Locations

Country	Name	City	State
United States	Mid Atlantic Retina- Wills Eye Institute	Philadelphia	Pennsylvania

Sponsors (2)

Lead Sponsor	Collaborator
Wills Eye	Mid Atlantic Retina

Country where clinical trial is conducted

United States, 

References & Publications (12)

Alvarez-Verduzco O, Garcia-Aguirre G, Lopez-Ramos Mde L, Vera-Rodriguez S, Guerrero-Naranjo JL, Morales-Canton V. Reduction of fluence to decrease pain during panretinal photocoagulation in diabetic patients. Ophthalmic Surg Lasers Imaging. 2010 Jul-Aug;41(4):432-6. doi: 10.3928/15428877-20100525-02. — View Citation

Chiu HH, Wu PC. Manual acupuncture for relieving pain associated with panretinal photocoagulation. J Altern Complement Med. 2011 Oct;17(10):915-21. doi: 10.1089/acm.2010.0082. — View Citation

Ko BW, Shim JH, Lee BR, Cho HY. Analgesic effects of tramadol during panretinal photocoagulation. Korean J Ophthalmol. 2009 Dec;23(4):273-6. doi: 10.3341/kjo.2009.23.4.273. — View Citation

Mainster MA. Wavelength selection in macular photocoagulation. Tissue optics, thermal effects, and laser systems. Ophthalmology. 1986 Jul;93(7):952-8. — View Citation

Mirshahi A, Lashay A, Roozbahani M, Fard MA, Molaie S, Mireshghi M, Zaferani MM. Pain score of patients undergoing single spot, short pulse laser versus conventional laser for diabetic retinopathy. Graefes Arch Clin Exp Ophthalmol. 2013 Apr;251(4):1103-7. doi: 10.1007/s00417-012-2167-5. — View Citation

Photocoagulation treatment of proliferative diabetic retinopathy. Clinical application of Diabetic Retinopathy Study (DRS) findings, DRS Report Number 8. The Diabetic Retinopathy Study Research Group. Ophthalmology. 1981 Jul;88(7):583-600. — View Citation

Richardson C, Waterman H. Pain relief during panretinal photocoagulation for diabetic retinopathy: a national survey. Eye (Lond). 2009 Dec;23(12):2233-7. doi: 10.1038/eye.2008.421. — View Citation

Tesha PE, Giavedoni LR, Berger AR, Altomare F, Chow DR, Navajas EV, Yoganathan P, Wong DT, Principe A. Subconjunctival lidocaine before laser treatment: a randomized trial. Ophthalmology. 2010 Sep;117(9):1810-4. doi: 10.1016/j.ophtha.2010.01.036. — View Citation

Vujosevic S, Martini F, Longhin E, Convento E, Cavarzeran F, Midena E. SUBTHRESHOLD MICROPULSE YELLOW LASER VERSUS SUBTHRESHOLD MICROPULSE INFRARED LASER IN CENTER-INVOLVING DIABETIC MACULAR EDEMA: Morphologic and Functional Safety. Retina. 2015 Aug;35(8):1594-603. doi: 10.1097/IAE.0000000000000521. — View Citation

Wu WC, Hsu KH, Chen TL, Hwang YS, Lin KK, Li LM, Shih CP, Lai CC. Interventions for relieving pain associated with panretinal photocoagulation: a prospective randomized trial. Eye (Lond). 2006 Jun;20(6):712-9. — View Citation

Yadav NK, Jayadev C, Mohan A, Vijayan P, Battu R, Dabir S, Shetty B, Shetty R; Medscape.. Subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy: safety profile and treatment outcome. Eye (Lond). 2015 Feb;29(2):258-64; quiz 265. doi: 10.1038/eye.2014.315. — View Citation

Zakrzewski PA, O'Donnell HL, Lam WC. Oral versus topical diclofenac for pain prevention during panretinal photocoagulation. Ophthalmology. 2009 Jun;116(6):1168-74. doi: 10.1016/j.ophtha.2009.01.022. — View Citation

* Note: There are 12 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Perceived patient pain assessment	Assessed using a standardized Wong-Baker faces pain scale	a single time point within 2 minutes of completing laser treatment	No
Secondary	Minimum power requirement to achieve moderate gray-white retinal burns		During treatment	No
Secondary	Time of treatment	Time required to treat with each laser	During treatment	No