Favorable vocal fold wound healing induced by platelet-rich plasma injection

The Effect of Using Perioperative Platelet-Rich Plasma on Wound Healing Rate and Prevention of Salivary Fistula Formation in Patients Undergoing Partial Parotidectomy

OBJECTIVES

This study aims to examine the effects of autologous platelet-rich plasma (PRP), which increases new connective tissue synthesis and revascularisation, on healing in parotid surgery wounds, prevention of salivary fistula formation, drain removal time and hospitalisation in the postoperative period.

MATERIALS AND METHODS

Fifty-four patients who had an operation on partial parotidectomy were randomised, and then two groups were created. PRP was obtained by centrifuging the blood taken from the patients in the study group at the end of the surgery. This obtained PRP was injected into the surgical site, and then the wound flap was closed by suturing. Patients were evaluated for parameters such as the development of salivary fistula, duration of drain removal, discharge time and all other complications during the postoperative 4 weeks.

RESULTS

Drain removal and discharge times of the PRP group cases were statistically shorter than those in the control group. The rate of development of a salivary fistula was remarkably high in the control group, but it was not statistically significant. A statistically significant correlation was found between the location of the compared tumour, the volume of material removed and the incidence of all complications.

CONCLUSIONS

PRP reduced the duration of drain removal and discharge times for those who had an operation on partial parotidectomy. Thus, the decreased discharge time provides both reduced health costs and reduced risk of developing nosocomial infections. Although it was not statistically significant, a significant difference was observed in the rates of salivary fistula development.

Platelet-rich plasma applications in the larynx: snake oil or stupendous?

PURPOSE OF REVIEW

To explore and summarize recent work examining the use of platelet-rich plasma (PRP) applications for vocal fold disorder.

RECENT FINDINGS

Intrachordal PRP injections have recently emerged as a treatment option for patients with damage to the lamina propria of the vocal fold (scar, atrophy, sulcus and inflammatory lesions). Studies support significant improvements in patient-reported and clinician-reported outcomes, and objective phonatory parameters. PRP demonstrates a good safety profile, absence of immune reactions, affordable cost model and improvement in mucosal wave features with resultant improved voice quality up to 12 months following treatment.

SUMMARY

PRP injection of the vocal folds is a novel repurposing of a previously validated technique, and emerging data shows consistent results across multiple centres, increasing confidence in use of this freely available material. Current published studies confirm improved voice outcomes compared with pretreatment measures and high patient satisfaction. Further research is required to properly assign the role of and ideal candidate for PRP applications, and to delineate durability of treatment.

Platelet Rich plasma injection of the vocal folds in benign vocal pathologies

PURPOSE

There are few options for treatment of dysphonia secondary to vocal pathology related to lamina propria scar, atrophy, sulcus, or inflammatory disorders. Platelet rich plasma (PRP) may provide anti-inflammatory and regenerative properties seen with other tissue engineering therapies without the risks associated with these treatments. We evaluated vocal fold (VF) injection of PRP for feasibility, phonatory effects, patient satisfaction and durability.

METHODS

Patients with dysphonia secondary to vocal fold scar, atrophy, sulcus and inflammatory lesions were included. PRP injections were administered in office, to bilateral vocal folds. Patients were followed up at 1 week, 1 month, 3 months and 6 months to assess outcomes (GRBAS scale, maximum phonation time, vocal fatigue index (VFI), voice handicap index (VHI-10) and stroboscopy).

RESULTS

75 intracordal PRP injections were administered to 48 patients. All injections were completed, and no adverse reactions were experienced. Improvements in VHI-10 scores at 1,3,6 months were seen (mean VHI 21.73 at baseline, 15.62 at six months, p < 0.001). 72.3% rated improvement at 7 or above on Likert scale. 95.7% of patients would consider a future PRP injection. Secondary outcomes VFI, MPT, and GRBAS also demonstrated significant improvements over time. Patients receiving a single PRP injection (n = 26) still demonstrated significant VHI-10 improvements at 1,3 and 6 months.

CONCLUSIONS

VF office PRP injections are feasible and safe and can provide phonatory benefit and reduce vocal effort in benign VF disorders. A single PRP injection is sufficient to provide sustained benefit in some cases.

LEVEL OF EVIDENCE

Level III: prospective cohort study.

Platelet Rich Plasma (PRP) Treatment in Recalcitrant, Bilateral Phono-traumatic Lesions

OBJECTIVE

Mature vocal fold nodules and fibrous phono-traumatic lesions that have failed standard voice therapy can be challenging. Autologous platelet-rich plasma (PRP) is rich in growth factors and easily obtained from a simple blood draw. Growth factor injection into the vocal folds may reverse the scar and inflammation in recalcitrant, bilateral phono-traumatic lesions such as mature vocal fold nodules. This study reports the short-term (3months) voice results after PRP injection in 11 subjects with recalcitrant, bilateral phono-traumatic lesions that have failed voice therapy.

MATERIALS AND METHODS

Serial autologous PRP injections were used to treat 11 patients with recalcitrant, bilateral phono-traumatic lesions in an office setting. All had prior conservative voice therapy or surgery and were deemed failures. Pre and post-treatment video stroboscopy, Voice Handicap Index (VHI-10), and Cepstral Spectral Index of Dysphonia (CSID) before and after treatment (3months) were tabulated and compared. An expert rater blinded to the treatment condition rated the stroboscopy and voice results.

RESULTS

At 3months postinjection, 9 of the 11 patients reported improved VHI-10 and noted sustained voice improvement after PRP injections. Median VHI-10 changed from 20 to 13 (P < 0.05 paired t test). The CSID scores changed from 17 to 5 (NS P > 0.05, paired t test). Nine of 11 patients reported improved vocal effort and stamina. Stroboscopy ratings were better after treatment than before treatment in 7 of the 11 subjects.

CONCLUSION

Short-term improvements in voice may occur in patients with recalcitrant, bilateral phono-traumatic lesions following PRP injection. PRP injections into the vocal folds may be a new treatment for nonsurgical intervention in patients with recalcitrant, bilateral phono-traumatic lesions.

LEVEL OF EVIDENCE

II.

Laryngeal Applications of Platelet Rich Plasma and Platelet Poor Plasma: A Systematic Review

BACKGROUND

Platelet rich plasma (PRP) and platelet poor plasma (PPP) are regenerative therapies that offer the potential for improving care for disorders of the larynx. The laryngeal applications of these substances have been examined in both animals and humans. The goal of this systematic review is to examine the various applications of PRP and PPP in laryngology, assess the protocols for preparation and application of these substances and evaluate the outcomes and complications in both humans and animals.

METHODS

A search of PUBMED was conducted in April 2021 using combinations of keywords of "platelet rich plasma" and "platelet poor plasma" with keywords such as "larynx," "vocal folds," "laryngology," and others. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRIMSA) guidelines were followed. Articles were reviewed by two independent coauthors and included based on selection criteria pertinent to the goals of this study. The risk of bias in the included studies was assessed by two independent co-authors using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Randomized Controlled Trials and JBI Critical Appraisal Checklist for Quasi-Experimental Studies. Data regarding the pathologies treated using PRP and PPP, PRP, and PPP preparation protocols, application protocols, human voice outcomes, histopathological animal outcomes, and complications were extracted from each of the studies and presented in tables.

RESULTS

Seven studies were included based on the selection criteria. PRP or PPP were used for vocal fold scar, sulcus, atrophy and palsy; acute vocal fold injury; glottic insufficiency, and graft healing. PRP or PPP were derived from autologous blood in a one- or two-step centrifugation process and administered via injection, soaking of cartilage grafts or topical application. Mean and median voice handicap index-10 (VHI-10) and voice handicap index (VHI) scores decreased following PRP or PPP injections in two human studies and one human study showed a similar VHI-10 score before and after PRP treatment. Videostroboscopy showed the absence of injection site reactions and at least temporary improvement in glottic gap or vibratory function following treatment in some patients. Other objective measures of voice outcomes in human studies showed improved phonatory function in the one-to-four-month period following PRP or PPP injections, with some patients experiencing a subjective decrease or return to baseline in phonatory function following the initial improvement period. Animal studies found elevated levels of growth factors, organized collagen deposition, decreased granulation tissue, increased vascularization, and increased cartilage proliferation in PRP treated laryngeal tissue.

DISCUSSION

PRP and PPP might have the potential to be safely used in the larynx and at least temporarily influence wound healing and vocal function. Further study using comparable outcome measurement tools is required to assess their role and efficacy in treating acute vocal fold injury, chronic vocal fold pathologies, graft healing, and other laryngeal applications.

Platelet-rich plasma in treatment of scar, atrophy, and sulcus: Short- and long-term results

Objective

Platelet-rich plasma (PRP) is rich in growth factors and is easily obtained from blood samples. Long-term data after PRP injection into the larynx should be improved. This study reports the short-term (3 months) and long-term (12 months) voice results after PRP injection.

Materials and Methods

Sixty-three patients with scars (n = 34), sulcus vocalis (n = 17), recalcitrant nodules (n = 5), atrophy (n = 4), or a combination of these (n = 3) were included (158 injections; median follow-up = 12.3 months). Stroboscopy, voice handicap index (VHI-10), and cepstral spectral index of dysphonia (CSID) before and after treatment (3 months) and at 12 months were tabulated.

Results

VHI-10 changed from 19.5 to 14 at 3 months and 21 to 15 in the long term. The CSID scores improved from 31 to 21 in the short term and 31 to 26 in the long term (p < 0.001, paired t-test). Patients reported improved vocal effort and stamina with slight VHI or CSID score changes. Stroboscopy revealed improved closure and mucosal waves. Patients with severe dysphonia were less likely to improve compared to those with mild to moderate dysphonia. Some patients showed short-term improvements and then deteriorated back to baseline CSID over time (p < .05, paired t-test).

Conclusion

Both short- and long-term improvements in voice following PRP injection have been reported. Patients with mild-to-moderate dysphonia had better outcomes. PRP injection is an alternative treatment for patients with mild-to-moderate dysphonia due to vocal fold scarring, sulcus, and atrophy.

Level of evidence

II Prospective case series treatment.

[The use of platelet-rich plasma in the treatment of cicatricial stenosis of the larynx and cervical trachea]

Despite the technical achievements of recent years in medicine, the problem of frequent recurrent stricture formation of the lumen of larynx and cervical trachea remains urgent. The etiology and pathogenesis of development of scar stenosis of the larynx and trachea were considered, and the analysis of the drugs' use for topical therapy in the comprehensive treatment of this pathology was conducted in the presented review. Special attention was paid to plasma enriched with platelets, its use in otorhinolaryngology, in particular in the treatment of laryngeal diseases. Positive and negative sides of the adjuvant therapy use have been identified. The search for means helping to prevent recurrent stricture formation of laryngeal lumen and cervical trachea determines the interest of the considered problem.

Tissue Engineering as a Promising Treatment for Glottic Insufficiency: A Review on Biomolecules and Cell-Laden Hydrogel

Glottic insufficiency is widespread in the elderly population and occurs as a result of secondary damage or systemic disease. Tissue engineering is a viable treatment for glottic insufficiency since it aims to restore damaged nerve tissue and revitalize aging muscle. After injection into the biological system, injectable biomaterial delivers cost- and time-effectiveness while acting as a protective shield for cells and biomolecules. This article focuses on injectable biomaterials that transport cells and biomolecules in regenerated tissue, particularly adipose, muscle, and nerve tissue. We propose Wharton's Jelly mesenchymal stem cells (WJMSCs), induced pluripotent stem cells (IP-SCs), basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), insulin growth factor-1 (IGF-1) and extracellular vesicle (EV) as potential cells and macromolecules to be included into biomaterials, with some particular testing to support them as a promising translational medicine for vocal fold regeneration.

The role of platelet-rich plasma in microlaryngeal surgery: a randomised, controlled trial

Objective

Platelet-rich plasma has gained interest over the two last decades, mainly because of its role in regenerative medicine. This work aimed to assess the role of intra-operative local application of platelet-rich plasma gel in the improvement of quality of voice after microlaryngeal surgery.

Method

This was a prospective comparative study that included 40 patients undergoing microlaryngeal surgery for benign vocal fold lesions. There were two groups divided equally into study group A and control group B. The assessment of voice was performed by videostroboscopy and acoustic analysis pre-operatively and at two weeks and one and three months post-operatively.

Results

The data demonstrated that all the stroboscopic and acoustic parameters showed significant improvement in both groups. Group A showed significant improvement regarding acoustic parameters at the third post-operative follow up when compared with group B.

Conclusion

Platelet-rich plasma has a beneficial effect on voice quality following microlaryngeal surgery based in particular on acoustic parameters.

The Effect of Platelet-Rich Plasma Injection on Short Term Vocal Outcomes Following Phonosurgery-A Pilot Study

Background and Objectives: The efficiency and optimal voice rest period following phonosurgery remains debatable. Platelet-rich plasma (PRP) is a safe and cheap alternative to many bioactive agents being studied on animal models, and is already in use in many medical areas. We investigate the short-term effects of PRP and voice rest on voice outcomes following phonosurgery as an alternative to voice rest alone. Materials and Methods: A prospective single-blinded pilot study was conducted. Sixteen patients with a diagnosis of vocal fold cyst and polyps were included, forming equal groups (PRP and voice rest vs. voice rest alone). Voice analysis was carried out on the preoperative day, day three, and week three following surgery. The measured parameters were fundamental frequency (F0), noise–signal ratio (NSR), harmonic poverty (HP), attack alteration (AL), pitch instability (PI), and amplitude instability (AI).VHI(Voice Handicap Index)-30 questionnaires were carried out before surgery and three weeks following surgery to assess the impact of subjective voice change on quality of life. PRP was obtained using commercial kits with separator gel. Results: An average 3.68-fold increase in platelets was obtained with PRP. No side effects were noted after injection. All voice parameters improved on day three and week three following surgery. Statistical significance was noted only in the fundamental frequency of male patients (p = 0.048) in favor of the PRP-voice rest group. In addition, the VHI- 30 questionnaire results between preoperative and postoperative assessments showed statistically significant differences in total VHI score (p = 0.02) as well as the physical (p = 0.05) and emotional (p = 0.02) scale in favor of the PRP-voice rest group. Conclusions: PRP presents short term safety in patients who undergo phonosurgery, although long-term outcomes are unknown. PRP and voice rest are superior to voice rest alone when considering subjective assessment of the voice. When analyzing acoustic parameters, PRP and voice rest are not superior to voice rest alone.

Use of platelet-rich plasma in irradiated patients to treat and prevent complications of head and neck surgery

Nowadays, many patients facing head and neck oncological surgery have a history of tissue irradiation. This represents an important risk factor for postsurgical complications, including dehiscences and fistulas. Platelet-rich plasma (PRP) obtained from the patient's blood represents an easy, fast and inexpensive method for the prevention and treatment of such complications. We present three cases of previously irradiated patients in which PRP was successfully used to prevent and treat postsurgical complications.

Comparison of the effects of platelet-rich plasma and dexamethasone ınjection on scar formation after vocal fold ınjury in rabbits

OBJECTIVES

In this study, a histopathological comparison was aimed between platelet-rich plasma (PRP) injection and dexamethasone injection in the prevention of scar formation after vocal fold injury.

MATERIALS AND METHODS

Electrocautery was applied to damage the right and left vocal folds of a total of 12 New Zealand rabbits. PRP obtained from the rabbit's own blood was injected into the right vocal fold, and dexamethasone was injected into the left vocal fold. After 8 weeks, the experimental animals were euthanized, and the levels of inflammatory cell infiltration, vascularization, collagen, elastin, and hyaluronic acid (HA) were compared in histopathological evaluation.

RESULTS

In statistical comparison of histopathological data obtained; in terms of plasma cell infiltration, vascularization, and edema parameters, statistically significant results were obtained in favor of the PRP group. Although the difference between collagen, elastin and HA, which are critical in vocal fold scar healing, was more positive in favor of PRP, no significant result was revealed in the statistical evaluation.

CONCLUSIONS

PRP injection in rabbits with vocal fold damage reveals similar characteristics with dexamethasone injection in preventing scar formation. PRP injection has favorable effects on vascularization, prevention of edema, and number of plasma cells.

Assessment of various intralesional injections in keloid: Comparative analysis

AIM

Intralesional triamcinolone is a gold standard in treating the keloids to comparation its effectiveness versus intralesional 5-fluorouracil intralesional verapamil and intralesional platelet-rich plasma.

PATIENTS AND METHODS

Several 160-cases were categorized into four groups of each Group-Containing 40 cases. Group-A (control) treated with intralesional triamcinolone and Group-B intralesional verapamil, Group-C intralesional 5-fluorouracil, and Group-D intralesional platelet-rich plasma. Patients were assessed for clinical response based on a decrease in the patient and observer scar assessment scale (POSAS) at baseline and the end of treatment.

RESULTS

The mean base-line POSAS score was 91 ± 10.98 SD check-in Group-A, 90 ± 10.85 in Group-B, 89 ± 10.06 in Group-C, and 92 ± 10.84 in Group-D.POSAS score after 24 weeks 36 ± 12.74 in Group-A, 29 ± 10.91 in Group-B, 39 ± 13.74 in Group-C, 36 ± 12.74 in Group-D. Statistically, a significant difference was observed between groups.

CONCLUSION

Intralesional verapamil reported to be the most effective therapy and platelet-rich plasma was effective as intralesional triamcinolone acetonide with no serious side effects and 5-fluorouracil was less effective in treating the keloids.

Short-Term Voice Improvement after Repeated Office-Based Platelet-Rich Plasma PRP Injection in Patients with Vocal Fold Scar, Sulcus, and Atrophy

INTRODUCTION

Improving the voice of patients with vocal atrophy, scar, and sulcus vocalis remains challenging. Platelet-rich plasma (PRP) is an autologous biological suitable for regenerative medicine. Office-based injections of PRP may serve as a source of improved wound healing.

MATERIALS AND METHODS

Thirty two office based injections of PRP were performed in 14 patients with scar, sulcus, and vocal atrophy (12 scars, 1 sulcus, and 1 atrophy). PRP was prepared using 20 cc blood draw and double centrifugation method. Injection laryngoplasty was performed using trans cervical or indirect trans oral technique (10 trans cervical, 22 trans-oral). Volume of PRP use was 0.5-0.7 cc per side. Injections varied from 1 to 3 injections at monthly intervals. Videostroboscopy, Voice Handicap Index (VHI-10), and an objective analysis of the voice using Cepstral Peak Prominence (Cepstral Spectral Index of Dysphonia) were recorded. An expert rater speech pathologist rated the audio and stroboscopy results.

RESULTS

Median follow-up was 15 months. No patients were made worse. The mean VHI-10 before the injection was 23. VHI-10 after the injection was 12.5 (P < 0.01). The mean Cepstral Spectral Index of Dysphonia score for CAPE-V sentence was 42.5 before the injection and 23.5 (P < 0.01) after the injection. The expert rater thought the post treatment was better (9/14 acoustic, 10/14 stroboscopy). Eleven of the 14 patients thought the intervention was worthwhile to repeat. The other 3 patients thought the improvement was transient.

CONCLUSION

Office PRP injection into the vocal fold of patients with scar, sulcus, and atrophy may result in short term voice improvements. It is a biological worth considering.

Botulinum toxin and platelet rich plasma as innovative therapeutic modalities for keloids

Keloids characterize a definitely challenging type of cutaneous scars for which a diversity of therapeutic modalities has been suggested. The aim of this work was to compare the therapeutic efficacy of intralesional injection of botulinum toxin type-A (BTX-A), platelet rich plasma (PRP), and triamcinolone acetonide (TAC) in keloids. A total of 60 keloids patients were enrolled and divided randomly into three equal groups. Group I treated by intralesional BTX-A injection, group II treated by intralesional PRP injection, and group III treated by intralesional TAC injection. Clinical assessment was done by Vancouver Scar Scale (VSS), Verbal Rating Scale (VRS), and dermoscopic examination. Additionally, histopathology and immunohistochemistry of connective tissue growth factor (CTGF) expression were evaluated. The results of this study revealed significant improvement of both VSS and VRS in response to all treatment modalities. There was significant improvement of VSS in BTX-A and PRP groups more than TAC group. However, no significant difference observed between BTX-A and PRP groups. Immunohistochemical examination showed significant decrease of CTGF expression after treatment in BTX-A and PRP groups more than TAC group. In conclusion, both BTX-A and PRP could yield a chance for cosmetically better outcomes in keloids treatment than conventional TAC injection.

Rheological Properties and Growth Factors Content of Platelet-Rich Plasma: Relevance in Veterinary Biomedical Treatments

Platelet-rich plasma (PRP) is a nontransfusional hemocomponent, considered as a powerful concentrate of growth factors (GFs) therapeutically used to stimulate tissue regeneration. The use of autologous PRP, as the patient’s own biological material, for therapeutic purposes represents a safe and effective alternative to conventional treatments in both human and veterinary medicine. The aim of this study was the characterization of canine PRP from rheological and biological points of view. Thus, a characterization of the viscoelastic properties of the PRP systems was performed in order to clarify the influence of different calcium concentrations, in the presence of autologous thrombin-rich solution, on the PRP gels’ mechanical properties, from which the applicability of these systems in biomedical treatments is strongly dependent. Then, an evaluation of the content of GFs in PRP, activated or not with thrombin, and stored at different temperatures (37 °C and −20 °C) was performed over time, outlining, for the first time, the importance of the effect of physiological temperature (37 °C) on the production of GFs. A clinical case study conducted in a dog with a complete rupture of the common calcaneal tendon (Achilles tendon) confirmed the relevance of this hemocomponent in the daily veterinary clinical activity and the potential translational value for human health.

Enhanced In Vivo Vascularization of 3D-Printed Cell Encapsulation Device Using Platelet-Rich Plasma and Mesenchymal Stem Cells

The current standard for cell encapsulation platforms is enveloping cells in semipermeable membranes that physically isolate transplanted cells from the host while allowing for oxygen and nutrient diffusion. However, long-term viability and function of encapsulated cells are compromised by insufficient oxygen and nutrient supply to the graft. To address this need, a strategy to achieve enhanced vascularization of a 3D-printed, polymeric cell encapsulation platform using platelet-rich plasma (PRP) and mesenchymal stem cells (MSCs) is investigated. The study is conducted in rats and, for clinical translation relevance, in nonhuman primates (NHP). Devices filled with PRP, MSCs, or vehicle hydrogel are subcutaneously implanted in rats and NHP and the amount and maturity of penetrating blood vessels assessed via histopathological analysis. In rats, MSCs drive the strongest angiogenic response at early time points, with the highest vessel density and endothelial nitric oxide synthase (eNOS) expression. In NHP, PRP and MSCs result in similar vessel densities but incorporation of PRP ensues higher levels of eNOS expression. Overall, enrichment with PRP and MSCs yields extensive, mature vascularization of subcutaneous cell encapsulation devices. It is postulated that the individual properties of PRP and MSCs can be leveraged in a synergistic approach for maximal vascularization of cell encapsulation platforms.

Combined intralesional triamcinolone acetonide and platelet rich plasma versus intralesional triamcinolone acetonide alone in treatment of keloids

Background: Keloids are benign fibro-proliferative growths occurring after skin injury or spontaneously. Intralesional triamcinolone acetonide (TA) is their first-line therapy, but commonly associated with side effects or recurrence. Platelet rich plasma (PRP) is an autologous blood-derived product with promising results in improving wound healing with lower keloid occurrence.Objective: To compare the efficacy of combined intralesional TA and PRP versus TA alone in keloids treatment.Methods: Forty patients with keloids were divided randomly into two equal groups (A and B). Both groups received intralesional TA (20 mg/ml) for four sessions, 3 weeks apart. Group A patients received additional intralesional PRP 1 week after TA injections. Evaluation was done after 3 months of follow up by Vancouver scar scale (VSS) and verbal rating scale (VRS) for pain and itching.Results: Both groups showed significant improvement in all parameters of VSS and VRS in comparison with baseline. Significantly better improvement in height, pigmentation, and pliability and overall VSS was detected in patients of group A. A significantly higher incidence of post-TA atrophy and hypopigmentation was observed in group B.Conclusion: Combining intralesional PRP with TA could yield cosmetically better outcomes in keloid treatment with lower incidence of TA-induced side effects especially atrophy and hypopigmentation.

Combined Use of Autologous Stromal Vascular Fraction Cells and Platelet-Rich Plasma for Chronic Ulceration of the Diabetic Lower Limb Improves Wound Healing

The discovery of stromal vascular fraction cells and platelet-rich plasma in promoting tissue regeneration has prompted a new idea for the treatment of chronic diabetic ulcer of the lower limb. The study aim was to evaluate the clinical efficacy of a new method that applied stromal vascular fraction cells and platelet-rich plasma together in the treatment of recalcitrant chronic diabetic ulcer. We conducted a single-center, prospective, open, noncontrolled study. Four patients (5 ulcers in total) who had received standard treatment for diabetic ulcer for at least 3 months that failed to heal was enrolled. All patients were treated with surgical debridement, cell suspension (stromal vascular fraction cells suspended by platelet-rich plasma) injection into the wound, and platelet-rich plasma gel coverage. Wounds were measured every week after treatment using a 2-dimensional digital camera and a 3-dimensional wound measurement device. All patients were followed-up for 4 months after the treatment. Four of the 5 ulcers healed completely within a mean of 71.75 ± 29.57 days. The average proportion of granulation tissue achieved 100% within 4 weeks for all cases. The wound size decreased to less than half of the original size for all cases 4 weeks after the treatment. Findings revealed that the new treatment is efficient to achieve wound healing in patients with recalcitrant chronic diabetic ulcer of lower limb.

Effects of phenytoin injection on vocal cord healing after mechanical trauma: An experimental study

Background/aim

Phenytoin is an anticonvulsant drug which causes fibroblast proliferation, collagen synthesis, and an increase in epidermal growth factor. Therefore, the aim of the present study is to evaluate the effect of phenytoin injection on the wound healing process in rats with vocal cord injury by histopathological methods.

Materials and methods

The vocal cords of 10 albino Wistar rats were damaged bilaterally; the left vocal cord was kept as the control group. Phenytoin was injected in the right vocal cord. Ten rats were sacrificed. The thickness of the lamina propria and density of the fibroblast and collagen were evaluated histopathologically.

Results

Thickness of the lamina propria was 18.0 ± 7.1 µm in the control group, 65.5 ± 10.7 µm in the phenytoin group. The density of fibroblast and collagen were statistically lower in the control group compared the phenytoin group (P < 0.05).

Conclusion

Phenytoin injection in rats after vocal cord injury significantly increased the thickness of the lamina propria and density of fibroblast and regular and mature collagen in the lamina propria. The findings in our study provide a feasible scientific view for adding phenytoin treatment to vocal cord surgeries in otolaryngology practice, but further studies are needed in order to evaluate the use of phenytoin in preventing the formation of scar tissue and possible effects on vocal cord vibration in humans after vocal cord injury.

Pathophysiology of Fibrosis in the Vocal Fold: Current Research, Future Treatment Strategies, and Obstacles to Restoring Vocal Fold Pliability

Communication by voice depends on symmetrical vibrations within the vocal folds (VFs) and is indispensable for various occupations. VF scarring is one of the main reasons for permanent dysphonia and results from injury to the unique layered structure of the VFs. The increased collagen and decreased hyaluronic acid within VF scars lead to a loss of pliability of the VFs and significantly decreases their capacity to vibrate. As there is currently no definitive treatment for VF scarring, regenerative medicine and tissue engineering have become increasingly important research areas within otolaryngology. Several recent reviews have described the problem of VF scarring and various possible solutions, including tissue engineered cells and tissues, biomaterial implants, stem cells, growth factors, anti-inflammatory cytokines antifibrotic agents. Despite considerable research progress, these technical advances have not been established as routine clinical procedures. This review focuses on emerging techniques for restoring VF pliability using various approaches. We discuss our studies on interactions among adipose-derived stem/stromal cells, antifibrotic agents, and VF fibroblasts using an in vitro model. We also identify some obstacles to advances in research.

Histopathologic Evaluation of Hyaluronic Acid and Plasma-Rich Platelet Injection into Rabbit Vocal Cords: An Experimental Study

Objective

Various materials are used by otolaryngologists for vocal cord injections in the management of vocal cord paralysis. An ideal injection material should be long-term effective, readily available, cheap, easy to prepare, have no donor morbidity, easy to use, biocompatible, resistant to resorption or migration, and easy to extract during revision. In this study, we aimed to see the histopathological effects of hyaluronic acid (HYA) and platelet-rich plasma (PRP) injections into the vocal cords of New Zealand rabbits.

Methods

PRP was injected into the right vocal cords of twelve rabbits, which was prepared from their serum (PRP group). HYA was injected into the left vocal cords of first six rabbits (numbered 1-6) (HYA group), and the left vocal cords of the other six rabbits (numbered 7-12) were followed with no intervention (control group). Two months later, histomorphological findings in the vocal cords were assessed by two experienced pathologists in seven parameters: chronic inflammation, mucosal atrophy, necrosis, neovascularization, fibrosis, foreign body reaction, and muscular atrophy. They were scored double-blinded as negative (0), mild (+1), moderate (+2), and severe (+3). Fisher's chi-square test was used to evaluate any statistical significance among the three groups.

Results

Chronic inflammation, mucosal atrophy, necrosis, foreign body reaction, and muscular atrophy parameters were scored as "0" for each preparate by both pathologists. For neovascularization and fibrosis, a stasistically significant difference was seen among the three groups (p<0.05). Neovascularization was increased in the PRP and HYA groups compared with the control group. No significant difference was observed in fibrosis when the groups were compared separately. After two months, two of the six vocal cords injected with HYA revealed HYA; however, none of the PRP-injected vocal cords showed PRP.

Conclusion

HYA and PRP can be safely injected into vocal cords. Our findings show that HYA is a biocompatible and safe injection material for clinical use. Only two of the six vocal cords showed HYA at the end of two months, suggesting that HYA is a short-term effective material. Similarly, PRP was also shown to be a short-term effective material and can be used in patients for testing purpose before using a long-term effective material. The advantages of PRP are that it is inexpensive, readily available, and completely inert as it is prepared from the subject itself.

Effects of Intracordal Estradiol and Dexamethasone Injection on Wound Healing in Vocal Fold Injuries

OBJECTIVE

The aim of this study was to investigate the effects of intracordal estradiol and dexamethasone injection on wound healing in vocal fold injuries.

STUDY DESIGN

A prospective controlled animal study was carried out.

SETTING

This study was conducted at a tertiary center.

SUBJECTS-METHODS

Ten rabbits were randomly divided into two groups. As surgical procedure, cordotomy technique was performed in the middle third of the vocal folds bilaterally. In the first group, 0.1 mL of dexamethasone was injected into the right side, and 0.1 mL of saline was injected into the left side. In the second group, 0.1 mL of estradiol was injected into the right side, and 0.1 mL of saline was injected into the left side. Animals were sacrificed after 1 month and laryngeal specimens were evaluated histopathologically.

RESULTS

No statistically significant difference was observed in terms of inflammatory response, epithelial thickness, type I and III collagen, and hyaluronic acid parameters in dexamethasone and estradiol injections compared to the saline injection. In terms of elastin level, estradiol injection demonstrated statistically higher values compared to the saline injection. Elastin level of dexamethasone injected vocal folds was not statistically different compared to the saline injection. No significant differences were observed in terms of inflammatory response, epithelial thickness, type I and III collagen, and hyaluronic acid parameters between the estradiol and dexamethasone injected vocal folds.

CONCLUSION

It is thought that the effects of estradiol or dexamethasone injections may have similar effects on wound healing in vocal fold injuries. Intracordal estradiol injection has positive effects on tissue elastin levels.

Keloid Management: A Retrospective Case Review on a New Approach Using Surgical Excision, Platelet-Rich Plasma, and In-office Superficial Photon X-ray Radiation Therapy

OBJECTIVE:

The objective of this retrospective study was to evaluate the efficacy of the authors’ combination therapy protocol for keloid treatment.

DESIGN:

Retrospective.

SETTING:

Plastic surgery office-based outpatient setting in New York City.

PATIENTS:

Forty patients with 44 keloid scars requiring surgical excision.

INTERVENTIONS:

Keloid scars were treated using surgical excision, platelet-rich plasma, and postoperative in-office superficial photon X-ray radiation therapy. Intralesional triamcinolone injections were administered once to 4 patients with poor results on scar scale assessment. Patient follow-up visits ranged from 3 to 11 months to assess for evidence of recurrence and adverse effects.

MAIN OUTCOME MEASURE(S):

For the purpose of this study, recurrence was defined as any sign of extraordinary erythema, induration, and hypertrophy beyond the site of excision.

MAIN RESULTS:

In the 16 keloids treated with 2 fractions, there was no evidence of recurrence. One of 25 keloids treated with 3 fractions demonstrated evidence of recurrence. One of 3 keloids treated with a single fraction displayed signs of recurrence. Postirradiation hyperpigmentation was noted in all patients.

CONCLUSIONS:

Surgical excision combined with platelet-rich plasma and postoperative in-office superficial radiation therapy achieved a 95.5% nonrecurrence rate at 1- to 3-month follow-up. This protocol appears to be a safe and viable option in the management of keloids and merits further randomized controlled study of its comparative efficacy.

Implications of anticoagulants and gender on cell counts and growth factor concentration in platelet-rich plasma and platelet-rich gel supernatants from rabbits

Objectives: Our objectives were as follows: 1) to validate a protocol for producing rabbit platelet-rich plasma (PRP); 2) to determine the influence of two anticoagulants, sodium citrate and acid-citrate-dextrose solution A, and gender on cell count in PRP and growth factor concentration in pure platelet-rich gel supernatants; 3) to correlate the variables evaluated.

Methods: Whole blood from 18 New Zealand rabbits (9 males and 9 females) was obtained with sodium citrate and acid- citrate-dextrose solution A for processing PRP fractions (A and B), which were evaluated for haematology. The PRP fractions were either activated with calcium gluconate or lysated with a detergent. The concentrations of transforming growth factor beta 1 and platelet-derived growth factor BB were assayed by ELISA.

Results: The sodium citrate PRP-B had significantly higher counts of platelets in comparison to PRP-A and whole blood obtained with the same anticoagulant and the homologous acid-citrate-dextrose solution A PRP fraction. The sodium citrate PRP-A had a significantly higher count of leukocytes compared to the homologous acid-citrate-dextrose solution A fraction. All the PRP fractions had a significant leuko-reduction when compared to whole blood. The sodium citrate PRP-A fraction from female rabbits had significantly lower platelet counts and significantly higher leukocyte counts than the same acid-citrate-dextrose solution A fraction. Growth factor concentration was not affected by the type of anticoagulant or gender.

Clinical significance: The type of anticoagulant and gender affected the cell counts in PRP, but they did not influence the growth factor concentration. More complete rabbit PRP studies should be performed before evaluating this type of substance in models of disease.

The effectiveness of platelet-rich plasma in an anosmia-induced mice model

OBJECTIVE

In this study, we aimed to functionally and morphologically demonstrate the effectiveness of platelet-rich plasma (PRP) on anosmia in a mouse model of anosmia.

STUDY DESIGN

Animal study.

METHODS

A total of 16 male mice were included. When selecting the mice, the food-finding test (FFT) was used to make sure that the animals could smell, and anosmia was induced by administration of intraperitoneal 3-methylindole. The mice were randomly divided into two groups of eight (groups A and B). After 1 week, topical PRP was administered to the mice in group A and topical saline was administered to the mice in group B. The FFT was again administered at 7, 14, and 21 days. The mice were sacrificed on day 21, the olfactory neuroepithelium was histopathologically examined, and the epithelial damage scores and epithelial thickness were measured.

RESULTS

After topical administration of PRP and saline, the difference in the average FFT values of the groups was statistically significant at 7, 14, and 21 days (P < 0,005). During the histopathological examination, the epithelial damage score was statistically significantly lower in the PRP group (P = 0.001) than in the saline group, and epithelial thickness was statistically significantly greater in the PRP group compared to the saline group (P = 0.003).

CONCLUSION

We showed that PRP administration has a curative effect on olfactory functions in an anosmia-induced mice model. However, there is a need for further research before PRP can be considered for use in patients with anosmia in clinical practice.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E157-E162, 2018.

Platelet-rich plasma in otolaryngology

Background:

Platelet-rich plasma is a novel material that is being used more frequently in many surgical specialties.

Methods:

A literature review on the current and potential uses of platelet-rich plasma in otolaryngology was performed.

Results:

There is limited evidence on the use of platelet-rich plasma in otolaryngology compared with other specialties: only 11 studies on various subspecialties (otology, rhinology and laryngology) were included in the final review.

Conclusion:

Based on the limited number of studies, we cannot draw safe conclusions about the value of platelet-rich plasma in otolaryngology. Nevertheless, the available literature suggests that platelet-rich plasma holds promise for future research and may have a number of clinical applications.

Effect of activated autologous platelet-rich plasma on proliferation and osteogenic differentiation of human adipose-derived stem cells in vitro

To investigate whether activated autologous platelet-rich plasma (PRP) can promote proliferation and osteogenic differentiation of human adipose-derived stem cells (hASCs) in vitro. hASCs were isolated from lipo-aspirates, and characterized by specific cell markers and multilineage differentiation capacity after culturing to the 3(rd) passage. PRP was collected and activated from human peripheral blood of the same patient. Cultured hASCs were treated with normal osteogenic inductive media alone (group A, control) or osteogenic inductive media plus 5%, 10%, 20%, 40%PRP (group B, C, D, E, respectively). Cell proliferation was assessed by CCK-8 assay. mRNA expression of osteogenic marker genes including alkaline phosphatase (ALP), osteopontin (OPN), osteocalcin (OCN) and core binding factor alpha 1 (Cbfa1) were determined by Real-Time Quantitative PCR Analysis (qPCR). Data revealed that different concentrations of activated autologous PRP significantly promoted hASCs growth in the proliferation phase compared to the without PRP group and resulted in a dose-response relationship. At 7-d and 14-d time point of the osteogenic induced stage, ALP activity in PRP groups gradually increased with the increasing of concentrations of PRP and showed that dose-response relationship. At 21-d time point of the osteogenic induced stage, PRP groups make much more mineralization and mRNA relative expression of ALP, OPN, OCN and Cbfa1 than that without PRP groups and show that dose-response relationship. This study indicated that different concentrations of activated autologous PRP can promote cell proliferation at earlier stage and promote osteogenic differentiation at later stage of hASCs in vitro. Moreover, it displayed a dose-dependent effect of activated autologous PRP on cell proliferation and osteogenic differentiation of hASCs in vitro.

Prevalence of laryngeal disease in South Korea: data from the Korea National Health and Nutrition Examination Survey from 2008 to 2011

PURPOSE

The aim of this study was to evaluate the prevalence of Benign Vocal Fold Lesion (polyp, cysts, nodules) and Leukoplakia in Korea.

MATERIALS AND METHODS

The data from the 2008 to 2011 Korea National Health and Nutrition Examination Surveys, which were cross-sectional survey of the civilian noninstitutionalized population of South Korea. A survey team that included an otolaryngology residents, nurses, and interviewers moved with a mobile examination unit and performed laryngologic interviews and examinations of vocal folds using rigid telescopic laryngoscopy on survey participants over 19 years old (n=19636).

RESULTS

Laryngoscopic examination revealed normal results in 19251 (98.04%) of those included in the survey. Abnormal laryngoscopic findings were observed in 1.96% of the population examined, and vocal cord nodules were the most common abnormal finding. The prevalence of vocal cord nodules was 0.99-1.72%, the prevalence of vocal cord polyps was 0.31-0.55%, the prevalence of vocal cysts was 0.04-0.17%, and the prevalence of vocal cord leukoplakia was 0.07-0.21%. There was no significant correlation of linear trend of prevalence by year, and there were no significant differences in prevalence between males and females.

CONCLUSION

This is the first nationwide epidemiologic study to assess the prevalence of Benign Vocal Fold Lesion (polyp, cysts, nodules) and Leukoplakia by both the Korean Otolaryngologic Society and the Ministry of Health and Welfare. The results of this large epidemiologic study provide valuable information regarding the prevalence of voice disorders and the management of laryngologic diseases.