Effects of Piezosurgery on the cochlear outer hair cells

The Impact of Piezoelectric Device in Cholesteatoma Endoscopic Surgery: Retrospective Evaluation of Safety and Functional Results

OBJECTIVE

Atticotomy represents an essential surgical step within the management of attical cholesteatoma during endoscopic ear surgery. The aim of the present study was to evaluate the safety and functional results of an endoscopic atticotomy performed with piezosurgery, in terms of audiological outcomes and tissue's healing.

METHODS

This is an observational retrospective study on patients with attical cholesteatoma who underwent endoscopic ear surgery with piezoelectric atticotomy and subsequent scutum reconstruction either with tragal cartilage or temporalis muscle fascia. Scutumplasty's status was evaluated via scheduled outpatient controls through an endoscopic check and classified as stable or unstable at least 10 months after surgery. A pre- and postoperative audiometric examination was performed in each patient.

RESULTS

Eighty-four patients were enrolled. In 50 out of 84 patients (59.52%), an exclusive endoscopic procedure was performed, whereas in 34 patients (40.48%) a combined microscopic/endoscopicapproach was adopted. In 72 cases (85.71%), scutum's reconstruction appeared to be normally positioned, whereas 12 patients developed a retraction pocket, which was self-cleaning in 8 of them and non-self-cleaning in the remaining 4. In 17 patients, a slight sensorineural hearing loss (between 5 and 15 dBHL) was observed, and in 2 patients, the loss was greater than 15 dBHL. Overall, no significative differences between pre- and postoperative pure-tone average bone thresholds resulted (p = 0.4983), though a mild significant hearing deterioration was detected by the specific analysis at 4000 Hz (p = 0.0291).

CONCLUSION

Piezosurgery represents an extremely useful tool in performing atticotomy during endoscopic tympanoplasties. Our data seem to support the safety of its usage in this specific step, as it did not lead to any significant sensorineural damage on overall pure-tone average. Moreover, satisfactory tissue healing in regard to scutum reconstruction was observed.

Endoscopic atticotomy for attic cholesteatomas using piezosurgery

BACKGROUND

Attic cholesteatomas can be exenterated by transcanal endoscopic ear surgery (TEES). In the limited operative field of exclusive transcanal endoscopic atticotomy, surgeons use either a piezosurgery scalpel or a drilling system to remove the posterior lateral bony wall of the epitympanum. We aimed to investigate the feasibility of using piezosurgery or microdrill for endoscopic atticotomy during exenteration of attic cholesteatomas.

METHODS

This study is a retrospective chart review of patients diagnosed with attic cholesteatoma, who were treated by exclusive TEES. The superior and posterior external auditory canal bones were excised using a piezosurgery scalpel or microdrill. Preoperative and postoperative hearing thresholds were measured by pure-tone audiometry.

RESULTS

The postoperative follow-up duration varied from 6 to 37 months. There were no significant differences in age, sex, laterality of the affected ear, and preoperative bone conduction thresholds between the piezosurgery scalpel and microdrill groups. The operative duration was longer in the piezosurgery group than in the microdrill group (135.6 ± 19.5 minutes vs 117.3 ± 29.1 minutes, p = 0.042). Seven of 30 (23.3%) patients in the microdrill group, but none in the piezosurgery group, had a friction injury from the drilling. Postoperative testing at higher frequencies of 2000, 3000, and 4000 Hz showed no deterioration in the bone conduction threshold in the piezosurgery group.

CONCLUSION

Endoscopic atticotomy performed using a piezosurgery scalpel is potentially safer but slower than using a microdrill for exenteration of attic cholesteatomas.

Piezoelectric ear surgery: a systematic review

BACKGROUND

The piezoelectric instrument (PEI) offers a novel technique for bone removal in ear surgery with a combination of micro-oscillation and cavitation. The aim of this review is to explore the advantages, disadvantages, and limitations of this instrument in comparison to the drill.

MATERIALS AND METHODS

We conducted a search of PubMed/MEDLINE and Google Scholar in accordance with the PRISMA recommendations. The primary selection included all studies reporting on the use of PEI in ear surgery or its effect on the inner ear. Only studies with a control group were included in the secondary selection.

RESULTS

The first search identified 49 studies between 2003 and 2022. These reported on a total of 1162 ear operations, during which PEI was used for various indications. Most data were based on uncontrolled retrospective studies or case reports (76%). Only one of the five controlled clinical studies was prospective and randomized. The advantages of PEI weighed against its limitations and disadvantages were critically analyzed in comparison to the drill.

CONCLUSION

Piezoelectric surgery is an innovative and promising surgical technique in the temporal bone. PEI appears to enable safer and more precise bone removal in close proximity to soft tissue when compared to the drill. The slower bone removal and cost factors represent current limitations to its wider use in ear surgery.

[Piezoelectric ear surgery: a systematic review. German version]

BACKGROUND

The piezoelectric instrument (PEI) offers a novel technique for bone removal in ear surgery with a combination of micro-oscillation and cavitation. The aim of this review is to explore the advantages, disadvantages, and limitations of this instrument in comparison to the drill.

MATERIALS AND METHODS

We conducted a search of PubMed/MEDLINE and Google Scholar in accordance with the PRISMA recommendations. The primary selection included all studies reporting on the use of PEI in ear surgery or its effect on the inner ear. Only studies with a control group were included in the secondary selection.

RESULTS

The first search identified 49 studies between 2003 and 2022. These reported on a total of 1162 ear operations, during which PEI was used for various indications. Most data were based on uncontrolled retrospective studies or case reports (76%). Only one of the five controlled clinical studies was prospective and randomized. The advantages of PEI weighed against its limitations and disadvantages were critically analyzed in comparison to the drill.

CONCLUSION

Piezoelectric surgery is an innovative and promising surgical technique in the temporal bone. PEI appears to enable safer and more precise bone removal in close proximity to soft tissue when compared to the drill. The slower bone removal and cost factors represent current limitations to its wider use in ear surgery.

Piezoelectric canalplasty for exostoses and osteoma

OBJECTIVE

To evaluate the safety profile and surgical technique for removal of symptomatic exostoses and osteoma of the external auditory canal with a micro-oscillating piezoelectric device.

METHOD

A chart review was conducted on patients undergoing piezoelectric canalplasty between 2019 and 2021 at tertiary referral hospital. Surgery was performed by two surgeons with varying experience. Bone removal was achieved using both osteotomy and osteoplasty. Postoperative complications, operative time and hearing outcome were evaluated.

RESULTS

The study comprised 16 patients (16 ears). No major complications occurred. The skin of the auditory canal was completely preserved in all patients without injury to the tympanic membrane. Except for one patient with known noise-induced hearing loss, there was no postoperative deterioration of the bone-conduction threshold more than 10 dB HL at any frequency. The difference of the bone-conduction threshold in pure-tone audiometry (average for 0.5, 1, 2 and 4 kHz) three weeks postoperatively had a median of 0.6 dB ± 5.7. One patient complained of temporary new tinnitus. One patient had prolonged wound healing. Mean operative time was comparable with literature data.

CONCLUSION

The atraumatic characteristics of the piezoelectric instrument enable low-risk removal of external auditory canal exostoses and osteoma. Through the combination of precise osteotomy and osteoplasty, this novel instrument has the potential to become established in routine canalplasty.

Ultrasonic bone removal from the ossicular chain affects cochlear structure and function

INTRODUCTION

Ultrasonic bone removal devices (UBD) are capable of cutting through bony tissue without injury to adjacent soft tissue. The feasibility and safety of using this technology for removal of bone from an intact ossicular chain (as might be required for otosclerosis or congenital fixation) was investigated in an animal model.

METHODS

This was a prospective animal study conducted on seven anesthetised adult chinchillas. An UBD was used to remove bone from the malleus head in situ. Pre and post-operative distortion product otoacoustic emission (DPOAE) levels and auditory brainstem response (ABR) thresholds were recorded. Scanning electron microscopy (SEM) was used to assess cochlear haircell integrity.

RESULTS

Precise removal of a small quantity of bone from the malleus head was achieved by a 30s application of UBD without disruption of the ossicular chain or tympanic membrane. DPOAEs became undetectable after the intervention with signal-to-noise ratios (SNR) < 5 dB SPL in all ears. Furthermore, ABR thresholds were elevated > 85 dB SPL in 13 ears. SEM showed significant disruption of structural integrity of the organ of Corti, specifically loss and damage of outer haircells.

CONCLUSIONS

Although UBD can be used to reshape an ossicle without middle ear injury, prolonged contact with the ossicular chain can cause structural and functional injury to the cochlea. Extensive cochlea pathology was found, but we did not investigate for recovery from any temporary threshold shift. In the authors' opinion, further study should be undertaken before consideration is given to use of the device for release of ossicular fixation.

Ultrasonic Wave Bone Cutting Technique (Piezotome) in Cochlear Implant Surgery by Veria Technique

To study use of ultrasonic wave bone cutting technique (piezotome) in cochlear implant surgery by veria technique. The Piezoelectric device is a bone cutting tool that transmits ultrasonic high frequency vibrations through a metallic tip to selectively cut bone while sparing the surrounding soft tissues. We have used the piezo tools instead of the perforator in over 50 cases of Cochlear Implant by the non mastoidectomy Veria technique [which uses a specially designed hand piece perforator with a guide (Kiratzidisa et al. in ORL J Otorhinolaryngol Relat Spec 64:413-416, 2002)]. These tools are helpful in: straightening the posterior bony canal wall, making the well for Implant bed, making space for excess electrodes and removing bone tissue close to dura without risk of injury to dura. Though use of Piezo tools in various otologic surgeries has been described but we feel the piezo tools will be an important tool in a CI surgeon's armament.

Occupational Noise Exposure and Risk for Noise-Induced Hearing Loss Due to Temporal Bone Drilling

BACKGROUND

Noise-induced hearing loss is one of the most common occupational hazards in the United States. Several studies have described noise-induced hearing loss in patients following mastoidectomy. Although otolaryngologists care for patients with noise-induced hearing loss, few studies in the English literature have examined surgeons' occupational risk.

METHODS

Noise dosimeters and sound level meters with octave band analyzers were used to assess noise exposure during drilling of temporal bones intraoperatively and in a lab setting. Frequency specific sound intensities were recorded. Sound produced using burrs of varying size and type were compared. Differences while drilling varying anatomic structures were assessed using drills from two manufacturers. Pure tone audiometry was performed on 7 to 10 otolaryngology residents before and after a temporal bone practicum to assess for threshold shifts.

RESULTS

Noise exposure during otologic drilling can exceed over 100 dB for short periods of time, and is especially loud using large diameter burrs > 4 mm, with cutting as compared with diamond burrs, and while drilling denser bone such as the cortex. Intensity peaks were found at 2.5, 5, and 6.3 kHz. Drilling on the tegmen and sigmoid sinus revealed peaks at 10 and 12.5 kHz. No temporary threshold shifts were found at 3 to 6 kHz, but were found at 8 to 16 kHz, though this did not reach statistical significance.

CONCLUSION

This article examines noise exposure and threshold shifts during temporal bone drilling. We were unable to find previous descriptions in the literature of measurements done while multiple people drilling simultaneously, during tranlabyrinthine surgery and a specific frequency characterization of the change in peach that appears while drilling on the tegmen. Hearing protection should be considered, which would still allow the surgeon to appreciate pitch changes associated with drilling on sensitive structures and communication with surgical team members. As professionals who specialize in promoting the restoration and preservation of hearing for others, otologic surgeons should not neglect hearing protection for themselves.

Effect of Piezoelectric Technique on Auditory Function on Postoperative Day One in Septorhinoplasty Surgery

AIM

To examine the effect of the piezoelectric application used increasingly for osteotomy and correction of nasal dorsum in septorhinoplasty surgeries on early auditory functions.

METHODS

Our study was conducted after the decision of 10840098-604.01.01-E.9057 taken from Istanbul Medipol University Clinical Research Local Ethics Committee. This study was designed to be prospective, randomized and controlled. Twenty patients between 18 and 50 years of age that piezoelectric technique was used in the study group and 10 patients in the same age range who underwent nasal surgery (endoscopic sinus surgery, septoplasty, lower concha radiofrequency and nasal valve surgery) for any reason in the control group were included in the study. Audiologic functions of the patients in both the groups were assessed by pure audio audiometry, tympanometry and distortion product otoacoustic emission test before the surgery and 24 hours after the surgery. The data obtained were statistically compared using the SPSS 22.0 program and P < 0.05 was considered significant.

RESULTS

Twenty patients (5 males, 15 females) that piezoelectric (ultrasonics) technique was used during septorhinoplasty in the study group and 10 patients (5 males, 5 females) in the control group were included in the study. In the study and the control groups, preoperative and postoperative air/bone path thresholds at the right and left ears did not differ significantly (P > 0.05) at 250, 500, 1000, 2000, 4000, 6000, and 8000 Hz. The results of distortion product otoacoustic emission results (signal/noise ratio) obtained postoperatively were not statistically significant (P > 0.05) with the results obtained preoperatively.

CONCLUSION

The results of the study show that the piezoelectric technique used in septorhinoplasty does not cause a negative effect on auditory functions. This study is the first comparative study to investigate the effect of piezoelectric technique used in septorhinoplasty surgery on auditory functions. After further clinical studies performed with well-selected and large patient population, the piezoelectric techniques can be a preferred technique during septorhinoplasty operations.

Reduction of Bone Dust with Ultrasonic Bone Aspiration

Objective

Postoperative headache is not uncommon after retrosigmoid vestibular schwannoma removal. Bone dust dispersed into the subarachnoid space during drilling may be responsible. If dispersion could be reduced, headache incidence might be decreased. An ultrasonic bone aspirator (UBA) containing an integrated suction at the tip may more effectively suction bone dust created during bone removal. The objective is to determine whether a UBA results in less bone dust dispersion than a standard otologic drill.

Study Design

Cadaveric temporal bone quantitative model.

Setting

Laboratory.

Subjects and Methods

Temporal bone blocks were placed in a watertight enclosure. Under irrigation, bone was removed by use of either a drill or a UBA. The settings of the UBA were varied. The irrigant containing bone dust was microfiltered, and bone dust was weighed. Differences were compared across groups (n = 2-9 per group). Ablation times were also recorded (n = 3 per group).

Results

Only 3% (SD = 1.6%, n = 7) of the drilled bone mass was re-collected as bone dust with the UBA under optimized settings (power = 15%, suction = 100%, irrigation = 15 mL/min) compared with 81% (SD = 10%, n = 4) with the drill and external suction ( P < .001). Increasing UBA power and reducing suction led to significantly more bone dust dispersal than with optimized settings. Varying irrigation did not have a significant effect. Bone ablation time was 1.4 times longer with the UBA at 50% power compared with the drill at maximum power.

Conclusions

The UBA resulted in approximately 25 times less bone dust dispersion than the otologic drill at optimized settings.

Effects of cochlear drilling with Piezosurgery Medical device in rats

OBJECTIVES/HYPOTHESIS

Drilling on the otic capsule for cochleostomy should be less traumatic to the cochlea with the Piezosurgery Medical device (PZ) than with a standard diamond drill (DD). "Soft" cochleostomy is used for preservation of residual hearing in cochlear implant patients. PZ drilling can be used for accurate cochleostomy placement with minimal soft-tissue damage and may be superior for atraumatic drilling on the cochlea, as compared with a DD. This study compared inner ear effects after drilling the rat otic capsule with the PZ versus the DD.

STUDY DESIGN

Prospective animal study using rats.

METHODS

Otic capsule drilling was performed on the left ear with the DD (n = 5) or the PZ (n = 5), while otic capsule temperature was monitored. Contralateral ears served as controls. The animals were sacrificed after 1 week. Organ of Corti damage was morphologically evaluated and compared between groups.

RESULTS

Basal turn hair cell loss was observed in all ears in the PZ group, regardless of drilling depth. However, no cochlear damage was found in any ears in the DD group.

CONCLUSIONS

Otic capsule drilling with the PZ results in greater trauma to the rat inner ear than drilling using conventional methods.

Piezoelectric stapedotomy: the importance of a micropulse program

CONCLUSIONS

We can consider the micropulse program as the best level of safety that should be used in all cases of piezoelectric stapedotomy.

OBJECTIVES

The aim of this study was to describe the importance of a micropulse program in determining the success of piezoelectric stapedotomy.

METHODS

A total of 112 patients (group A) affected by primary otosclerosis underwent piezoelectric stapedotomy for otosclerotic stapes fixation. A specific operative program was created to perforate the stapes footplate: this program makes it possible to perforate the footplate of the stapes with a predetermined and non-modifiable temporization. Before and 1 year after surgery, all the patients underwent the following instrumental examinations: pure-tone audiometry, tympanometry, transient-evoked otoacoustic emissions, distortion product otoacoustic emissions, and auditory brainstem response. Results were compared with those obtained from 30 patients who underwent piezoelectric stapedotomy without the specific operative program (group B).

RESULTS

At 1 year after surgery, with regard to the pure-tone audiometry test, all patients had an air-bone gap (ABG) reduction: no worsening of the bone conduction and no postoperative sensorineural hearing loss were found. In group A, there was a closure of the ABG within 10 dB in all patients.

Results of revision mastoidectomy with Piezosurgery(®)

CONCLUSION

For otologic revision surgery, the advantage of the piezoelectric device appears real because it is possible to perform a 'blind' cutting of bone with fewer precautions necessary for soft tissues such as the facial nerve, lateral sinus, and dura mater.

OBJECTIVES

The aim of this study was to determine the efficiency of the piezoelectric device in revision surgery for chronic otitis media.

METHODS

A total of 30 patients had revision mastoidectomy with previous canal wall up mastoidectomy. The piezoelectric device was used in all intraoperative steps. Before surgery and 1 month and 1 year after surgery, all the patients underwent the following instrumental examinations: pure-tone audiometry, tympanometry, transient-evoked otoacoustic emissions, distortion product otoacoustic emissions, auditory brainstem response, and electronystamographic recording.

RESULTS

The piezoelectric device provided effective cutting, with excellent control and without side effects on the adjacent structures of the middle and inner ear (lateral sinus, facial nerve, and/or dura mater). Postoperatively, all patients had an uneventful recovery with no evidence of audiovestibular deficit or side effects. Among 30 cases followed for 1 year, 29 (97%) maintained a dry and safe ear. Intermittent otorrhea with perforation of the tympanic membrane occurred in one patient (3%).

Piezosurgery versus microdrill in intact canal wall mastoidectomy

Piezosurgery is a recently developed system for cutting bone with microvibrations. The objectives of the present study were to report our experience with the piezoelectric device in the intact canal mastoidectomy, and to compare the results with traditional method by means of microdrill. A non-randomized controlled trial was undertaken on 60 intact canal wall mastoidectomy performed using the piezoelectric device (30 patients) or the microdrill (30 patients). Before 1 month and 1 year after surgery, all the patients underwent the following instrumental examinations: otomicroscopic evaluation of the tympanic membrane and external auditory duct, bone conduction threshold audiometry, tympanometry, transient-evoked otoacoustic emissions with linear click emission, distortion product otoacoustic emissions, auditory brainstem response (ABR) by MK 12-ABR screener with natus-ALGO2e (Amplifon, Milan, Italy), and electronystamographic recording. The piezoelectric device is proved to be effective in sclerotic and pneumatic mastoid, with an excellent control and without side effects on the adjacent structures of the middle and inner ear (lateral sinus, facial nerve, and/or dura mater). The operation time has been the same as compared with microdrill, and the average hospital stay was significantly (p < 0.05) shorter. Postoperatively, all patients had uneventful recovery with no evidence of audiovestibular deficit or side effects. Our experience highlights the safety of the piezoelectric device on the anatomic structures of the middle and inner ear, and demonstrates its efficiency in terms of cutting precision and healing process.

Piezosurgery for removal of symptomatic ear osteoma

Piezosurgery is an ultrasound instrument (24.7-29.5 kHz) that is able to cut the bone without necrosis and nonmineralized tissue damage. The aim of this work has been to determine the applicability and efficiency of the piezoelectric device in the excision of symptomatic ear osteomas. 10 patients affected by osteoma of the external auditory canal (EAC) (6 right, 4 left) were enrolled. Patients underwent excision of the EAC osteoma through a transcanal approach, with the piezoelectric device. Before and 6 months after surgery, all the patients underwent pure-tone audiometry, tympanometry, transient-evoked otoacoustic emissions, distortion product otoacoustic emissions, auditory brainstem response, and electronystamographic recording. The piezoelectric device provided excellent control without side effects on the adjacent structures of the external, middle and inner ear. The piezoelectric device is a new bony scalpel using the microvibrations at ultrasonic frequency so that soft tissue (nerve, vessel, dura mater, skin, etc.) will not be damaged even on accidental contact with the cutting tip. A feature of the piezoelectric device is its good manageability, which makes it easy for a well-trained otologic surgeon to create a straight osteotomy line: this renders the piezoelectric device suitable for bone surgery and for removal osteomas of the EAC.

Learning Curve for Piezosurgery in Well-Trained Otological Surgeons

OBJECTIVE: Piezosurgery is an ultrasound instrument (24.7–29.5 kHz) capable of cutting bone without necrosis and nonmineralized tissue damage. The aim of this work has been to determine the time required for a well-trained surgeon to perform otological surgery with the piezoelectric device.

STUDY DESIGN: Case series with planned data collection. Sixty-three patients affected by otosclerosis and 63 by chronic otitis media were enrolled. For each disease, patients were divided into three numerically equal groups, with each group assigned to a well-trained otological surgeon. Patients underwent stapedotomy (n = 63) and intact canal wall tympanoplasty (n = 63) with the piezoelectric device.

SETTING: ENT Department, University of Genoa (Italy).

SUBJECTS AND METHODS: We recorded “skin-to-skin” operation time, surgical success, surgical complication, and hospital stay duration. Before and one year after surgery, all patients underwent pure-tone audiometry, tympanometry, recording of transient-evoked otoacoustic emission, recording of distortion product otoacoustic emission, auditory brainstem response, and electronystamographic recording.

RESULTS: In each surgical technique, the piezoelectric device provided excellent control without side effects on the adjacent structures of the middle and inner ear.

CONCLUSION: The piezoelectric device is a new bony scalpel that uses microvibrations at ultrasonic frequency so that soft tissue (nerve, vessel, dura mater, etc) will not be damaged even on accidental contact with the cutting tip. A feature of the piezoelectric device is its good manageability, which makes it easy for a well-trained otological surgeon to create a straight osteotomy line without any learning period: this renders the piezoelectric device suitable for bone surgery.