2.1. Study Design

The study was conducted in the ENT department of our institution from August 2019 to September 2020. It was designed as a retrospective study and included adult patients with chronic dry eardrum perforation who were candidates for various types of tympanoplasty (tympanoplasty type I-IV). The patients underwent either a cartilage graft or a cartilage graft combined with the PRF graft.

Inclusion criteria: adult patients diagnosed with chronic eardrum, which had been dry for at least 6 months, without any clinical and paraclinical signs of active infection, without history of otological surgery or history of radiation to the head and neck region were included in the study. Patients with diabetes or hypertension were included, provided that their conditions were well controlled with therapy.

Exclusion criteria: unwillingness to participate or refusal of the PRF grafting, presence of congenital malformations in the head area, presence of wet perforation or active infection, and comorbidities that contraindicate ear surgery. Additionally, patients on chronic antiplatelet or anticoagulant treatment, as well as those in whom the procedure for preparing PRF failed, were also excluded from the study.

All 20 patients who underwent cartilage graft with the addition of a PRF membrane were included in the study (PRF group). Additionally, there were 96 patients who underwent tympanoplasty with a cartilage graft. We used stratified randomization, considering the age of PRF group patients, and included 27 patients who underwent tympanoplasty with a cartilage graft in the control group. Each patient underwent anamnesis and comprehensive clinical examination, which included an assessment of the entire ENT region. Additionally, otological examination was performed. Otomicroscopy was utilized to evaluate the characteristics of the eardrum perforation, such as size, location, and the presence of otorrhea or cholesteatoma. Audiological assessment, specifically pure-tone audiometry, was conducted to measure the air-bone gap and hearing threshold. Otomicroscopy was employed to categorize the perforations based on their size, classifying them as small (less than 50% of the total surface area), medium (50–75% of the total surface area), or large (more than 75% of the total surface area).

Postoperative evaluation included otoendoscopy and otomicroscopy at 1, 3, 6, and 12 months after surgery. These examinations aimed to assess the healing process of the eardrum, verify the integrity of the graft, and identify any presence of discharge, residual perforation, granulation tissues, cholesteatoma recurrence, or residual. Additionally, pure-tone audiometry was conducted at the 12-month mark to quantify the postoperative air-bone gap and measure the gain in hearing threshold.

All the evaluations (otoendoscopy, otomicroscopy, hearing assessment) were performed by the same team, under the same conditions, using the same equipment on both ears. The hearing investigation was performed in soundproof rooms, using an Interacoustic Audiometer Affinity Suite. Tonal sounds were used with standard frequencies (0.125, 0.25, 0.5, 1, 2, 4, and 8 kHz for air conduction and 0.5, 1, 2, 3, and 4 kHz, for bone conduction), thus measuring the air-bone gap and audiometric hearing threshold (measured by averaging the hearing thresholds at 0.5, 1, 2, and 4 kHz).

During the tympanoplasty procedure, the surgeons utilized Schambaugh’s incision in the operated ear, creating a tympanomeatal flap. The flap was then elevated to gain access to the tympanic cavity. Following this, any inflamed tissue within the tympanic cavity was removed, and ossiculoplasty was performed if necessary, using either a PORP (Partial Ossicular Replacement Prosthesis) or TORP (Total Ossicular Replacement Prosthesis) prosthesis. The perforation was repaired using a thinned tragal cartilage graft in group 1, while in group 2, both thinned tragal cartilage and a PRF membrane were used. The PRF membrane was larger than the perforation and the cartilage graft, and it was placed using the onlay method, positioned over the sealed perforation and the tympanomeatal flap. The final steps of the surgery involved suturing the Schambaugh’s incision and packing the external ear canal with gauze containing antibiotic ointment. The gauze was kept in place locally for 7 days and then removed under microscopic examination (Figure 1).

Closure of the perforation with cartilage graft and PRF membrane after removal of the packing of the external ear (a) and 1 month postoperative (b).

Following the completion of the procedure, patients in both groups received broad-spectrum antibiotic treatment for one week. They were also advised to refrain from blowing their nose, getting the operated ear wet, and to attend regular postoperative follow-up appointments.

The preparation of autologous PRF was performed prior to initiating the ear surgery. The anaesthesia team collected a 10 mL sample of peripheral venous blood into special tubes without anticoagulant. The collected blood sample was immediately centrifuged for 12 min at 3000× g rpm using a Choukroun centrifuge. The centrifugation process resulted in the formation of three distinct layers: a bottom layer containing red blood cells, a middle layer consisting of the fibrin clot, and a top layer consisting of acellular plasma (Figure 2). The PRF clot was carefully extracted and then pressed for 8 min, transforming it into a thin membrane (Figure 3). This PRF membrane was subsequently placed as a plug over the sealed perforation during the surgical procedure.

PRF—(a) 3 layers of centrifugated peripherical venous blood without anticoagulant and (b) fibrin clot.

The PRF thin membrane ready to use for ear surgery.