Otopathologic evaluation of temporalis fascia grafts following successful tympanoplasty in humans

Graft Healing Process Following Cartilage Myringoplasty Without Trimming of the Perforation Margin

Objective: The objective of this study was to endoscopically evaluate the graft healing process and graft success rate following cartilage myringoplasty, without trimming of the perforation margin or external ear canal (EAC) packing. Material and Methods: Patients with chronic tympanic membrane (TM) perforation underwent endoscope cartilage underlay myringoplasty, without trimming perforation margin or EAC packing. The healing process of the cartilage graft and the graft success rate were evaluated at 6 months postoperatively. Results: Fifty-eight ears were included in this study. At 1 week postoperatively, clinical inosculation and neovascularization of the graft were observed in small- and medium-sized perforations, but not in large or subtotal perforations. At 2 weeks postoperatively, graft clinical inosculation and neovascularization were completed in the small- and medium-sized perforations; however, neovascularization of the graft had only just begun in the large perforations. At 3 weeks postoperatively, completion of the graft clinical inosculation was achieved in 57 of the 58 ears. At 4 weeks postoperatively, complete neovascularization was achieved in all perforations. Of the 58 ears, postoperative infection resulted in residual perforation in 1 ear, and an insufficient graft resulted in residual perforation in a large perforation without infection. Overall, the graft success rate was 96.6% (56/58). There was no correlation between the graft success rate and graft neovascularization score. Conclusions: The graft healing process experienced the dilation of the blood vessels of the remnant TM, graft clinical inosculation, and neovascularization following cartilage myringoplasty without trimming of the perforation margin and EAC packing; however, the graft success rate was not related to the endoscopic graft neovascularization scores.

Outcomes of regenerative treatment for over 200 patients with tympanic membrane perforation

OBJECTIVE

To evaluate outcomes of a regenerative treatment (RT) for over 200 patients with tympanic membrane perforation (TMP). The RT-TMP method involves a gelatin sponge, basic fibroblast growth factor (bFGF) and fibrin glue.

METHODS

The study population included 216 patients and 234 ears (male: female =100:116; age 1-93 years). All enrolled patients were treated with RT-TMP in which TMP edges were disrupted mechanically and a gelatin sponge immersed in bFGF was inserted into the perforation. Fibrin glue was then dripped over the sponge. Patient outcomes including TMP closure rates, change in hearing level, and complications were obtained from retrospective medical chart reviews. The TMP was examined three or more weeks after surgery. The treatment was repeated up to 4 times until complete TMP closure was achieved.

RESULTS

After mechanical disruption, the perforation size was Grade I, ≤1/3 of entire TM area in 22 ears (9.4 %), Grade II, 1/3-2/3 of entire TM in 77 ears (32.9 %) and Grade III, ≥2/3 of entire TM area in 135 ears (57.7 %). The overall TMP closure rates were 97.0 % (227/234). Complete TMP closure was achieved in 68.8 % (161/234), 22.6 % (53/234), 4.7 % (11/234) and 0.9 % (2/234) of ears after 1, 2, 3 and 4 treatments, respectively. In 7 of 234 ears (3.0 %), the TMPs were not closed completely after 4 treatments. There was no correlation between TMP size after mechanical disruption and number of treatments required to achieve complete closure (Fisher's exact test p = 0.70). The mean air-conduction hearing threshold at low frequency improved from 57.3 ± 16.7 dB before treatment to 37.3 ± 16.0 dB (p < 0.0001) after closure of TMPs. For middle and high frequencies, the improvement was 49.0 ± 19.3 dB to 36.9 ± 17.9 dB (p < 0.0001) and 57.7 ± 22.9 dB to 49.2 ± 23.3 dB (p < 0.0001), respectively. The mean air-bone gaps also improved significantly, and were within 10 dB at 250 Hz, 500 Hz and 1 kHz, and 11 dB at 2 kHz. One or more complications occurred in 32 patients (32/216; 14.8 %). The most common complication was formation of an epithelial pearl (16 ears; 6.8 %), followed by severe TM retraction (9 ears; 3.8 %) and otitis media with effusion (6 ears; 2.6 %). There were no serious complications that caused deterioration of the patient's general condition.

CONCLUSION

Our results showed that RT-TMP had high success rates for TMP closure and good hearing improvement and produced no severe complications that could affect general health status. This novel therapy is simple, safe and minimally invasive, and could help improve the quality of life in patients with TMP.

Design of medical tympanostomy conduits with selective fluid transport properties

Implantable tubes, shunts, and other medical conduits are crucial for treating a wide range of conditions from ears and eyes to brain and liver but often impose serious risks of device infection, obstruction, migration, unreliable function, and tissue damage. Efforts to alleviate these complications remain at an impasse because of fundamentally conflicting design requirements: Millimeter-scale size is required to minimize invasiveness but exacerbates occlusion and malfunction. Here, we present a rational design strategy that reconciles these trade-offs in an implantable tube that is even smaller than the current standard of care. Using tympanostomy tubes (ear tubes) as an exemplary case, we developed an iterative screening algorithm and show how unique curved lumen geometries of the liquid-infused conduit can be designed to co-optimize drug delivery, effusion drainage, water resistance, and biocontamination/ingrowth prevention in a single subcapillary-length-scale device. Through extensive in vitro studies, we demonstrate that the engineered tubes enabled selective uni- and bidirectional fluid transport; nearly eliminated adhesion and growth of common pathogenic bacteria, blood, and cells; and prevented tissue ingrowth. The engineered tubes also enabled complete eardrum healing and hearing preservation and exhibited more efficient and rapid antibiotic delivery to the middle ear in healthy chinchillas compared with current tympanostomy tubes, without resulting in ototoxicity at up to 24 weeks. The design principle and optimization algorithm presented here may enable tubes to be customized for a wide range of patient needs.

Trilayer temporalis fascia interposition graft: A reliable technique for nasal septal perforation repair

PURPOSE

Nasal septal perforation (NSP) repair is a complex procedure with variable techniques and success rates. In this study we describe NSP repair using a trilayer interposition graft of temporalis fascia and thin polydioxanone (PDS) plate without intranasal flaps and report outcomes in our patient population.

MATERIALS AND METHODS

IRB-approved retrospective review of 20 consecutive patients presenting to a tertiary medical center with NSP from September 2018 to December 2020 and who underwent NSP repair via our trilayer temporalis fascia interposition graft. De-identified patient data was obtained from the medical record and stored on an encrypted secure server. Descriptive statistics were examined for each variable.

RESULTS

All 20 NSP repairs demonstrated durable repair with complete mucosal coverage at last follow-up (average 7 months). Complete resolution of preoperative symptoms was achieved in 85 % of patients, with partial resolution in the remaining 15 %. Of the 20 perforations 25 % were small (<1 cm), 50 % medium (1-2 cm), and 25 % large (>2 cm). The only surgical complication was a single intranasal synechiae. No graft harvest site complications were noted.

CONCLUSION

The application of a trilayer temporalis fascia - PDS plate interposition graft without intranasal flaps is highly effective for repair of NSP.

Endoscopic transcanal transtympanic myringoplasty vs. endoscopic transcanal tympanoplasty: 1-year follow-up study

BACKGROUND

Endoscopic transcanal transtympanic myringoplasty (ETTM) is a relatively easier technique than endoscopic transcanal tympanoplasty (ETT) for repairing tympanic membrane perforations. No studies have compared the outcomes of these two procedures with tragal perichondrium after 1-year. Furthermore, there is no evidence-based stratification according to variations in perforation size in endoscopic ear surgery. Therefore, we compared the 1-year outcomes of ETTM and ETT stratified according to perforation size.

METHODS

Patients who underwent ETT and ETTM to repair eardrum perforations with a tragal perichondrium graft were identified. Pure-tone audiometric tests and otoscopic examination were performed to assess hearing outcomes and perforation sizes both preoperatively and at least 1 year postoperatively.

RESULTS

In total, 158 patients (159 ears) were included. ETT was performed on 83 ears, and ETTM was performed on 76 ears. The ETTM procedure time was 10-minutes shorter than that for ETT ( p < 0.001). Perforation size was significantly correlated with graft take-rate. For large perforations, the ETT success rate was significantly higher than that of ETTM (91.7% vs. 78.9%). Success rates for small-medium perforations were comparable for both methods ( p > 0.05). However, for medium perforations, the graft take-rate of ETT reached a plateau after 6 months, while that of ETTM gradually declined during the 12-month follow-up. Both groups had a comparable mean postoperative air-bone gap gain ( p = 0.666).

CONCLUSION

ETTM is suitable for repairing small perforations, whereas ETT is preferred for large perforations. Both methods, and particularly ETTM, should be employed cautiously for medium perforations.

Drug Delivery across Barriers to the Middle and Inner Ear

The prevalence of ear disorders has spurred efforts to develop drug delivery systems to treat these conditions. Here, recent advances in drug delivery systems that access the ear through the tympanic membrane (TM) are reviewed. Such methods are either non-invasive (placed on the surface of the TM), or invasive (placed in the middle ear, ideally on the round window [RW]). The major hurdles to otic drug delivery are identified and highlighted the representative examples of drug delivery systems used for drug delivery across the TM to the middle and (crossing the RW also) inner ear.

Mechanics of Total Drum Replacement Tympanoplasty Studied With Wideband Acoustic Immittance

OBJECTIVE

Poor hearing outcomes often persist following total drum replacement tympanoplasty. To understand the mechanics of the reconstructed eardrum, we measured wideband acoustic immittance and compared the mechanical characteristics of fascia-grafted ears with the normal tympanic membrane.

STUDY DESIGN

Prospective comparison study.

SETTING

Tertiary care center.

METHODS

Patients who underwent uncomplicated total drum replacement with temporalis fascia grafts were identified. Ears with healed grafts, an aerated middle ear, and no other conductive abnormalities were included. All patients underwent pre- and postoperative audiometry. Wideband acoustic immittance was measured with absorbance and impedance computed. Fascia-grafted ears were compared with normal unoperated ears.

RESULTS

Eleven fascia-grafted ears without complications were included. Postoperatively, the median air-bone gap was 15 dB (250-4000 Hz), with variation across frequency and between ears. Fifty-six control ears were included. Absorbance of fascia-grafted ears was significantly lower than that of normal ears at 1 to 4 kHz (P < .05) but similar below 1 kHz. Impedance magnitude demonstrated deeper and sharper resonant notches in fascia-grafted ears than normal ears (P < .05), suggesting lower mechanical resistance of the fascia graft.

CONCLUSION

The mechanics of fascia-grafted ears differ from the normal tympanic membrane by having lower absorbance at mid- to high frequencies and thus poor sound transmission. The lower resistance in fascia-grafted ears may be due to poor coupling of the graft to the malleus. To improve sound transmission, grafts for tympanic membrane reconstructions would benefit from refined mechanical properties.

The Pretragal Superficial Musculoaponeurotic System Fascia: A New Graft Material for Transcanal Tympanoplasty

OBJECTIVE

To compare outcomes of transcanal endoscopic tympanoplasty reconstructed using pretragal superficial musculoaponeurotic system (SMAS) fascia versus temporalis fascia.

STUDY DESIGN

Retrospective patient review and posttreatment questionnaire survey.

SETTING

Tertiary referral center.

PATIENTS

Sixty adult patients with chronic dry tympanic membrane perforation.

INTERVENTIONS

Patients underwent transcanal endoscopic type I tympanoplasty reconstructed using the SMAS fascia between September 2017 and May 2018; outcomes were compared with a matched cohort of patients where the temporalis fascia was used.

MAIN OUTCOME MEASURES

Tympanic membrane closure rate, audiogram threshold, duration of procedure, and donor site scar satisfaction survey.

RESULTS

Sixty patients were included in this study and were evenly divided into the SMAS and temporalis fascia groups. These cohorts were matched for age, sex, side of lesion, perforation size, and preoperative hearing level. The closure rate was 96.7% (29/30) and 93.3% (28/30) (p = 1.0), mean hearing gain was 8.3 ± 6.4 dB versus 8.2 ± 7.1 dB for air-conduction (p = 0.970) and 7.6 ± 5.1 dB versus 8.2 ± 6.8 dB for air-bone gap (p = 0.716), and mean surgical duration was 137.3 ± 23.0 versus 132.2 ± 27.3 minutes (p = 0.432) for the SMAS and temporalis fascia groups, respectively; there were no statistically significant differences for all the parameters listed. The posttreatment questionnaire survey revealed significantly higher acceptance of the SMAS fascia method.

CONCLUSION

This preliminary outcome report of SMAS fascia grafting in transcanal endoscopic type I tympanoplasty showed equivalent surgical outcomes and better cosmetic satisfaction compared with the temporalis fascia. The SMAS fascia is a reasonable alternative to conventional techniques for transcanal tympanoplasty.

Forward and Reverse Middle Ear Transmission in Gerbil with a Normal or Spontaneously Healed Tympanic Membrane

Tympanic membranes (TM) that have healed spontaneously after perforation present abnormalities in their structural and mechanical properties; i.e., they are thickened and abnormally dense. These changes result in a deterioration of middle ear (ME) sound transmission, which is clinically presented as a conductive hearing loss (CHL). To fully understand the ME sound transmission under TM pathological conditions, we created a gerbil model with a controlled 50% pars tensa perforation, which was left to heal spontaneously for up to 4 weeks (TM perforations had fully sealed after 2 weeks). After the recovery period, the ME sound transmission, both in the forward and reverse directions, was directly measured with two-tone stimulation. Measurements were performed at the input, the ossicular chain, and output of the ME system, i.e., at the TM, umbo, and scala vestibuli (SV) next to the stapes. We found that variations in ME transmission in forward and reverse directions were not symmetric. In the forward direction, the ME pressure gain decreased in a frequency-dependent manner, with smaller loss (within 10 dB) at low frequencies and more dramatic loss at high frequency regions. The loss pattern was mainly from the less efficient acoustical to mechanical coupling between the TM and umbo, with little changes along the ossicular chain. In the reverse direction, the variations in these ears are relatively smaller. Our results provide detailed functional observations that explain CHL seen in clinical patients with abnormal TM, e.g., caused by otitis media, that have healed spontaneously after perforation or post-tympanoplasty, especially at high frequencies. In addition, our data demonstrate that changes in distortion product otoacoustic emissions (DPOAEs) result from altered ME transmission in both the forward and reverse direction by a reduction of the effective stimulus levels and less efficient transfer of DPs from the ME into the ear canal. This confirms that DPOAEs can be used to assess both the health of the cochlea and the middle ear.

Developing a novel meatal areolar tissue autograft for minimally invasive tympanoplasty

BACKGROUND

We developed an easy and minimally invasive method of transmeatal tympanoplasty using meatal areolar tissue (MAT) grafts to achieve less postoperative morbidity or surgical scarring. We compared the functional and anatomical results of the developed method with conventional endaural tympanoplasty with a temporalis fascia (TF) graft.

METHODS

In this retrospective cohort study, 58 patients (59 ears) with simple chronic otitis media who underwent type I tympanoplasty between January 2016 and August 2018 were included. All surgeries were performed in a tertiary referral hospital and by the same senior surgeon. The tympanic membrane (TM) was repaired with either a TF or an MAT graft.

RESULTS

Healing of the perforated TM and improvement in a hearing test by air-bone gap (ABG) closure were identified. Postoperative wound conditions were also evaluated. Twenty-eight ears were grafted with MAT, and 31 ears were grafted with TF. Graft success was observed in 26 patients (92.9%) in the MAT group and 28 patients (90.3%) in the TF group. Both groups showed functional improvement compared with the preoperative measurements. The postoperative pure tone audiogram (p = 0.737), ABG closure (p = 0.547), and graft success rate (p = 0.726) were not significantly different between the two groups. Neither wound dehiscence nor keloid formation was observed in our patients.

CONCLUSION

Both MAT and TF grafts revealed satisfactory surgical and functional results. Compared with the conventional endaural approach with TF grafts, the new transmeatal approach method with an MAT graft causes relatively minimal trauma and results in better wound cosmetics. This method represents an easy, minimally invasive surgery and shows comparatively good results.

High-Frequency Conductive Hearing following Total Drum Replacement Tympanoplasty

OBJECTIVES

Conventional reporting of posttympanoplasty hearing outcomes use a pure-tone averaged air-bone gap (ABG) largely representing a low-frequency sound conduction. Few studies report high-frequency conductive hearing outcomes. Herein, we evaluate high-frequency ABG in patients following temporalis fascia total drum replacement.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary care center.

SUBJECTS AND METHODS

All patients who underwent type 1 tympanoplasty using a lateral graft total drum replacement technique between August 2016 and February 2019 were identified. Patients with pre- and postoperative audiograms were included. Low-frequency ABG was calculated as the mean ABG at 250, 500, and 1000 Hz. High-frequency ABG was calculated at 4 KHz. Pre- and postoperative ABGs were compared.

RESULTS

Twenty-three patients were included, and the mean age at surgery was 44 years (range, 9-68 years). Perforation etiology was from trauma (n = 14) or chronic otitis media (n = 9). Preoperative mean low-frequency ABG was 27.8 ± 12.6 dB and mean high-frequency ABG was 21.5 ± 15.1 dB (P = .044). Postoperatively, the mean low-frequency ABG was significantly reduced by 15.5 ± 13.3 dB (P < .001) while the mean high-frequency ABG insignificantly changed (reduced by 2.6 ± 16.2 dB, P = .450).

CONCLUSION

In a series of patients undergoing temporalis fascia total drum replacement, low-frequency ABG improved; however, high-frequency conductive hearing loss persists. Conventional methods of reporting ABG may not identify persistent high-frequency ABG. These results merit further study across a range of tympanoplasty graft materials and surgical techniques.

Recovery from tympanic membrane perforation: Effects on membrane thickness, auditory thresholds, and middle ear transmission

Sounds delivered to the ear move the tympanic membrane (TM), which drives the middle-ear (ME) ossicles and transfers the acoustic energy to the cochlea. Perforations of the TM result in hearing loss because of less efficient sound conduction through the ME. The patterns of TM motions, and thus ME sound transmission, vary with frequency and depend on many factors, including the TM thickness. In this study, we measured TM thickness, auditory brainstem responses (ABR), and ME transmission immediately following a controlled pars tensa perforation and after 4 weeks of spontaneous recovery in a gerbil model. It is found that after recovery, the hearing thresholds showed a sloping pattern across frequencies: almost back to normal levels at frequencies between 2 and 8 kHz, sloping loss in the low (<2 kHz) and mid-frequency (8-30 kHz) range, and little restoration at frequencies above 30 kHz. This pattern was confirmed by the measured ME pressure gains. The thickness of the healed TM did not return to normal but was 2-3 times thicker over a significant portion of the membrane. The increased thickness was not limited to the perforated area but expanded into intact regions adjacent to the perforation, which led to an increased thickness in general. Combined, these results suggest that TM thickness is an important factor in determining its vibration patterns and efficiency to transfer sounds to the ossicles and thus influencing ME sound transmission, especially for high-frequency sounds. The results provided both structural and functional observations to explain the conductive hearing loss seen in patients with abnormal TMs, e.g., caused by otitis media, spontaneously healed post-perforation, or repaired via tympanoplasty in the clinic.