Human blood-derived topical treatments are increasinglybeing used in clinical practice for treating chronic severe ocular surfacedisease. Blood-derived products are advantageous in that they mimic certaincomponents of natural tears, providing a mixture of growth factors and cytokinesto the ocular surface. In addition, blood-derived therapies have also beenstudied for the treatment of pigment epithelial detachments, corneal ulcers,recurrent erosion syndrome, chemical injury, limbal stem cell deficiency andsuperior limbic keratoconjunctivitis.
There are various blood-derived preparations that can beused to treat ocular surface disease. Platelet preparations have also been usedto treat ocular surface disease, including platelet-rich plasma (PRP), plasmarich in growth factors (PRGF) and platelet lysate. The advantage of plateletpreparations is that they contain increased concentrations of growth factors,anti-inflammatory cytokines, and other platelet derivatives that have a role inwound healing and tissue regeneration. However, while they show promisingresults, blood-derived products can be costly and inconvenient for somepatients. In addition, there is a lack of consensus regarding the use of bloodproducts in the field of ophthalmology since many studies are based onheterogeneous blood products.
Platelet rich plasma is made by isolating and subsequentlyconcentrating platelets in plasma. PRP can be prepared using a single ortwo-step centrifugation process. Platelets store several biologically activeagents such as growth factors inside granules, including platelet-derivedgrowth factor (PDGF), epidermal growth factor (EGF), fibroblast growth factor(FGF), transforming growth factor (TGF), nerve growth factor (NGF) and insulin-likegrowth factor (IGF). PDGF, which is present in PRP, is thought to play a majorrole in wound healing, increasing the number of repaired cells, stimulatingangiogenesis and supporting the development of new blood vessels and activatedmacrophages.
The purpose of the study by Nadelmann et al was to determinewhether the addition of PRP eye drops for patients with severe ocular surfacedisease refractory to conservative measures provides subjective and objectiveclinical improvements.
A retrospective case series was conducted of patients whowere prescribed PRP eye drops. Subjects were excluded if they did not havefollow-up, underwent intraocular surgery prior to follow-up, received nervegrowth factor treatments, or did not have a baseline examination withphotography. Symptoms were assessed using the Ocular Surface Disease Index(OSDI). Patients also underwent a slit lamp exam, ocular surface staining withfluorescein and lissamine green, and Schirmer testing.
The charts of 47 patients treated with PRP drops for ocularsurface disease were reviewed. Sixty-four eyes of 32 patients were included inthe study who had photographs of lissamine green staining taken at baseline andat follow-up. Thirteen patients (28%) had ocular graft-versus-host disease, 16patients (34%) had Sjögren's syndrome, and 4 patients (8.5%) had rheumatoidarthritis. There was a statistically significant decrease in OSDI score frombaseline to follow-up (39.5 vs 30.8 points, p = 0.02). Among the 64 eyesincluded, 9 (14%) had an improvement in conjunctival lissamine green staining,while 6 (9%) had an increase in staining at follow-up. Among the 20 eyes withSchirmer testing, there was a borderline significant increase in score frombaseline to follow-up (5.9 vs 9.7, p = 0.06). Among the 44 eyes that hadcorneal fluorescein staining (CFS) reported, 8 (18.2%) had decreased stainingand 2 (4.5%) had increased staining at follow-up.
In this study, authors found that patients treated with PRPhad a statistically significant improvement in dry eye symptoms as measured bythe OSDI. The mean difference in the OSDI score was 8.6 points, which isclinically significant. In addition, most eyes that were treated had stable orimproved lissamine green conjunctival staining at follow-up. Among the 44 eyesthat had fluorescein staining reported at baseline and follow-up examinations,18.2% had decreased staining and 4.5% had increased staining on follow-up
Authors found that treatment with PRP drops was associatedwith a significant improvement in dry eye symptoms in patients with ocularsurface disease. The majority of eyes treated had stable or decreased ocularsurface staining at follow-up. Future larger prospective and comparativestudies are needed to further evaluate the efficacy of PRP drops for treatingocular surface disease.
Source: Nadelmann et al; Clinical Ophthalmology 2022:16
https://doi.org/10.2147/OPTH.S391536