Management of Deep Retinal Capillary Ischemia by Electromagnetic Stimulation and Platelet-Rich Plasma: Preliminary Clinical Results

The Effect of a Rotating Magnetic Field on the Regenerative Potential of Platelets

Platelets are actively involved in tissue injury site regeneration by producing a wide spectrum of platelet-derived growth factors such as PDGF (platelet-derived growth factor), IGF-1 (insulin-like growth factor), TGF-β1 (transforming growth factor β), FGF (fibroblast growth factor), etc. A rotating magnetic field (RMF) can regulate biological functions, including reduction or induction regarding inflammatory processes, cell differentiation, and gene expression, to determine the effect of an RMF on the regenerative potential of platelets. The study group consisted of 30 healthy female and male volunteers (n = 15), from which plasma was collected. A portion of the plasma was extracted and treated as an internal control group. Subsequent doses of plasma were exposed to RMF at different frequencies (25 and 50 Hz) for 1 and 3 h. Then, the concentrations of growth factors (IGF-1, PDGF-BB, TGF-β1, and FGF-1) were determined in the obtained material by the ELISA method. There were statistically significant differences in the PDGF-BB, TGF-β1, IGF-1, and FGF-1 concentrations between the analyzed groups. The highest concentration of PDGF-BB was observed in the samples placed in RMF for 1 h at 25 Hz. For TGF-β1, the highest concentrations were obtained in the samples exposed to RMF for 3 h at 25 Hz and 1 h at 50 Hz. The highest concentrations of IGF-1 and FGF-1 were shown in plasma placed in RMF for 3 h at 25 Hz. An RMF may increase the regenerative potential of platelets. It was noted that female platelets may respond more strongly to RMF than male platelets.

Management of toxic optic neuropathy via a combination of Wharton's jelly-derived mesenchymal stem cells with electromagnetic stimulation

PURPOSE

To investigate the effect of the combination of Wharton's jelly derived mesenchymal stem cells (WJ-MSC) and high frequency repetitive electromagnetic stimulation (rEMS) in the therapy of toxic optic neuropathies with severe symptoms after the available current therapy modalities which were unsucessful.

MATERIAL AND METHODS

This prospective, open-label clinical phase-3 study was conducted at Ankara University Faculty of Medicine, Department of Ophthalmology between April 2019 and April 2021. Thirty-six eyes of 18 patients with toxic optic neuropathy (TON) were included in the study. Within 1-3 months after the emergency interventions, patients with various degrees of sequela visual disturbances were studied in this clinical trial. The cases were divided into three groups according to similar demographic characteristics. Group 1: Consists of 12 eyes of 12 patients treated with the WJ-MSC and rEMS combination in one eye. Group 2: Consists of 12 eyes of 12 patients treated with only rEMS in one eye. Group 3: Consists of 12 eyes of six patients treated with only WJ-MSC in both eyes. The course was evaluated by comparing the quantitive functional and structural assessment parameters measured before and at the fourth month of applications in each group.

RESULTS

The mean best corrected visual acuity (BCVA) delta change percentages of the groups can be ranked as: Group 1 (47%) > Group 3 (32%) > Group 2 (21%). The mean fundus perimetry deviation index (FPDI) delta change percentages of the groups can be ranked as: Group 1 (95%) > Group 2 (33%) > Group 3 (27%). The mean ganglion cell complex (GCC) thickness delta change (decrease in thickness) percentages can be ranked as: Group 1 (- 21%) > Group 3 (- 15%) > Group 2 (- 13%). The visual evoked potential (VEP) P100 latency delta change percentages of the groups can be ranked as: Group 1 (- 18%) > Group 3 (- 10%) > Group 2 (- 8%). The P100 amplitude delta change percentages of the groups can be ranked as: Group 1 (105%) > Group 3 (83%) > Group 2 (24%).

CONCLUSION

Toxic optic neuropathies are emergent pathologies that can result in acute and permanent blindness. After poisoning with toxic substances, progressive apoptosis continues in optic nerve axons and ganglion cells. After the proper first systemic intervention in intensive care clinic, the WJ-MSC and rEMS combination seems very effective in the short-term period in cases with TON. To prevent permanent blindness, a combination of WJ-MSC and rEMS application as soon as possible may increase the chance of success in currently untreatable cases. Trial Registration ClinicalTrials.gov ID: NCT04877067.

Paracentral acute middle maculopathy: from diagnosis toward clinical perspectives

In this review of literature, we reviewed the current state of knowledge on paracentral acute middle maculopathy (PAMM). The diversity of clinical manifestations, a variety of related cardiovascular and ocular conditions, as well as reported idiopathic cases, allow considering PAMM as a distinct clinical phenomenon or a syndrome. Taking into account already described and potential associations with systemic and ocular morbidity, PAMM may apply for a place of an important clinical biomarker not only for ocular but for systemic disorders in a broad cohort of patients. However, the understanding of the pathophysiology of PAMM and of its actual clinical significance is far from complete, and further studies are warranted.

Treatment of resistant chronic central serous chorioretinopathy via platelet-rich plasma with electromagnetic stimulation

Background: To evaluate whether subtenon injection of platelet-rich plasma (PRP) with retinal electromagnetic stimulation (rEMS) is effective in therapy-resistant chronic central serous chorioretinopathy (CSCR). Design: Prospective, sequential. Materials & methods: The study included 22 eyes with resistant chronic CSCR. Cases receiving micropulse laser or additional photodynamic therapy, subtenon PRP, and subtenon PRP + rEMS were classified as times 1, 2 and 3, respectively. Results: At time 3, the mean best-corrected visual acuity was 85.7 and 97.0 letters before and after the procedures, respectively (p = 0.01). Submacular thickness improved by 17, 27 and 51% at times 1, 2 and 3 respectively. Conclusion: For treating resistant CSCR, subtenon PRP + rEMS should be considered as an effective and safe option. Trial Registration: ClinicalTrials.gov ID: NCT04224831.

Management of Retinitis Pigmentosa via Platelet-Rich Plasma or Combination with Electromagnetic Stimulation: Retrospective Analysis of 1-Year Results

PURPOSE

To investigate whether the natural progression rate of retinitis pigmentosa can be decreased by subtenon autologous platelet-rich plasma application alone or combination with retinal electromagnetic stimulation.

METHODS

The study includes retrospective analysis of 60 patients with retinitis pigmentosa. Patients constitute three groups with similar demographic characteristics: the combined management group (group 1) consists of 20 patients with retinitis pigmentosa (40 eyes) who received combined retinal electromagnetic stimulation and subtenon platelet-rich plasma; the subtenon platelet-rich plasma-only group (group 2) consisted of 20 patients with retinitis pigmentosa (40 eyes); the natural course (control) group (group 3) consists of 20 patients with retinitis pigmentosa (40 eyes) who did not receive any treatment. Horizontal and vertical ellipsoid zone width, fundus perimetry deviation index, and best corrected visual acuity changes were compared within and between groups after a 1-year follow-up period.

RESULTS

Detected horizontal ellipsoid zone percentage changes were + 1% in group 1, - 2.85% in group 2, and - 9.36% in group 3 (Δp 1 > 2 > 3). Detected vertical ellipsoid zone percentage changes were + 0.34% in group 1, - 3.05% in group 2, and - 9.09% in group 3 (Δp 1 > 2 > 3). Detected fundus perimetry deviation index percentage changes were + 0.05% in group 1, - 2.68% in group 2, and - 8.78% in group 3 (Δp 1 > 2 > 3).

CONCLUSION

Platelet-rich plasma is a good source of growth factors, but its half-life is 4-6 months. Subtenon autologous platelet-rich plasma might more effectively slow down photoreceptor loss when repeated as booster injections and combined with retinal electromagnetic stimulation.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT04252534.

Management of retinitis pigmentosa by Wharton's jelly derived mesenchymal stem cells: preliminary clinical results

PURPOSE

The aim of this study is to determine if umbilical cord Wharton's jelly derived mesenchymal stem cells implanted in sub-tenon space have beneficial effects on visual functions in retinitis pigmentosa patients by reactivating the degenerated photoreceptors in dormant phase.

MATERIAL AND METHODS

This prospective, open-label, phase-3 clinical trial was conducted between April of 2019 and October of 2019 at Ankara University Faculty of Medicine, Department of Ophthalmology. 32 RP patients (34 eyes) were included in the study. The patients were followed for 6 months after the Wharton's jelly derived mesenchymal stem cell administration, and evaluated with consecutive examinations. All patients underwent a complete routine ophthalmic examination, and best corrected visual acuity, optical coherens tomography angiography, visual field, multifocal and full-field electroretinography were performed. The quantitative results were obtained from a comparison of the pre-injection and final examination (6th month) values.

RESULTS

The mean best corrected visual acuity was 70.5 letters prior to Wharton's jelly derived mesenchymal stem cell application and 80.6 letters at the 6th month (p = 0.01). The mean visual field median deviation value was 27.3 dB before the treatment and 24.7 dB at the 6th month (p = 0.01). The mean outer retinal thickness was 100.3 μm before the treatment and 119.1 μm at 6th month (p = 0.01). In the multifocal electroretinography results, P1 amplitudes improved in ring1 from 24.8 to 39.8 nv/deg2 (p = 0.01), in ring2 from 6.8 to 13.6 nv/deg2 (p = 0.01), and in ring3 from 3.1 to 5.7 nv/deg2 (p = 0.02). P1 implicit times improved in ring1 from 44.2 to 32.4 ms (p = 0.01), in ring2 from 45.2 to 33.2 ms (p = 0.02), and in ring3 from 41.9 to 32.4 ms (p = 0.01). The mean amplitude improved in 16 Tds from 2.4 to 5.0 nv/deg2 (p = 0.01) and in 32 Tds from 2.4 to 4.8 nv/deg2 (p = 0.01) in the full-field flicker electroretinography results. Full field flicker electroretinography mean implicit time also improved in 16 Tds from 43.3 to 37.9 ms (p = 0.01). No ocular or systemic adverse events related to the two types of surgical methods and/or Wharton's jelly derived mesenchymal stem cells itself were observed during the follow-up period.

CONCLUSION

RP is a genetic disorder that can result in blindness with outer retinal degeneration. Regardless of the type of genetic mutation, sub-tenon Wharton's jelly derived mesenchymal stem cell administration appears to be an effective and safe option. There are no serious adverse events or ophthalmic / systemic side effects for 6 months follow-up. Although the long-term adverse effects are still unknown, as an extraocular approach, subtenon implantation of the stem cells seems to be a reasonable way to avoid the devastating side effects of intravitreal/submacular injection. Further studies that include long-term follow-up are needed to determine the duration of efficacy and the frequency of application.

TRIAL REGISTRATION

SHGM56733164. Redistered 28 January 2019 https://shgm.saglik.gov.tr/organ-ve-doku-nakli-koordinatorlugu/56733164/203 E.507.