Piezosurgery in otologic surgery: Four years of experience

Use of piezoelectric instrumentation in craniofacial surgery

PURPOSE OF REVIEW

The use of piezoelectric instrumentation is increasingly recognized as an alternative to traditional bone-cutting techniques across a wide array of surgeries. Here, we provide an overview of the technique, including device principles, benefits, and drawbacks. We also review its use in craniofacial surgery.

RECENT FINDINGS

Piezoelectric surgery is a minimally invasive bone-cutting system with lower risk of damage to surrounding soft tissue structures. Indications for its use are rapidly expanding across multiple fields, including craniofacial surgery. To date, piezosurgical techniques have been most widely adopted and studied in the contexts of rhinoplasty, orthognathic surgery, and cranioplasty in craniosynostosis. Piezosurgery can facilitate more precise and consistent osteotomies while decreasing morbidities associated with traditional osteotomy techniques. Primary limitations include cost and concerns regarding increased operative times secondary to operator learning curves and decreased cutting efficiency.

SUMMARY

Piezoelectric surgery represents an alternative to traditional bone-cutting modalities to improve precision, consistency, and safety of osteotomies. Further research is needed to better understand the efficacy of the technique as well as potential for additional applications.

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.

Piezosurgery versus Conventional Cutting Techniques in Craniofacial Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Despite its increasing use in craniofacial surgery, the evidence for piezosurgery over conventional bone-cutting techniques has not been critically appraised. The purpose of this systematic review and meta-analysis was to identify and assess the evidence that exists for the use of piezosurgery in craniofacial surgery.

METHODS

A systematic review was undertaken using a computerized search. Publication descriptors, methodologic details, and outcomes were extracted. Articles were assessed using the methodologic index for nonrandomized studies and Cochrane instruments. Random effects meta-analysis was completed.

RESULTS

Thirty-nine studies were included. Most studies were published within the past 5 years (51.3 percent) and were randomized controlled trials (56.4 percent). The mean age of patients was 27 years (range, 0.2 to 57 years), and the mean sample size was 44 (range, 12 to 180). Meta-analysis revealed that compared to conventional instruments, piezosurgery had a lower postoperative incidence of sensory disturbance, principally in mandibular procedures (OR, 0.29; 95 percent CI, 0.11 to 0.77; p = 0.01) and pain at postoperative day 3 (mean difference, -0.86; 95 percent CI, -1.20 to -0.53; p < 0.01). There was no statistically significant difference in operating room time (mean difference, 8.60; 95 percent CI, -1.27 to 18.47; p = 0.80) or osteotomy time (mean difference, 0.35; 95 percent CI, -2.99 to 3.68; p = 0.84). Most studies were clinically homogenous (92 percent) and of high quality based on the methodologic index for nonrandomized studies instrument (84 percent). Few studies had domains at high risk of bias based on the Cochrane instrument (28.6 percent).

CONCLUSIONS

Piezosurgery has considerable benefits when compared to conventional instruments. Future studies should investigate its cost-effectiveness and benefits in terms of blood loss, edema/ecchymosis, and patient satisfaction.

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.

Decompression of the geniculate ganglion and labyrinthine segments of the facial nerve through a middle cranial fossa approach using an ultrasonic surgical system: an anatomic study

PURPOSE

The aim of this study is to evaluate the feasibility and the safety of a novel, alternative method for bone tissue management in facial nerve decompression by a middle cranial fossa approach. Several applications of Piezosurgery technology have been described, and the technique has recently been extended to otologic surgery. The piezoelectric device is a bone dissector which, using micro-vibration, preserves the anatomic integrity of soft tissue thanks to a selective action on mineralized tissue.

METHODS

An anatomic dissection study was conducted on fresh-frozen adult cadaveric heads. Facial nerve decompression was performed by a middle cranial fossa approach in all specimens using the piezoelectric device under a surgical 3D exoscope visualization. After the procedures, the temporal bones were examined for evidence of any injury to the facial nerve or the cochleovestibular organs.

RESULTS

In all cases, it was possible to perform a safe dissection of the greater petrosal superficial nerve, the geniculate ganglion, and the labyrinthine tract of the facial nerve. No cases of semicircular canal, cochlea, or nerve damage were observed. All of the dissections were carried out with the ultrasonic device without the necessity to replace it with an otological drill.

CONCLUSION

From this preliminary study, surgical decompression of the facial nerve via the middle cranial fossa approach using Piezosurgery seems to be a safe and feasible procedure. Further cadaveric training is recommended before intraoperative use, and a wider case series is required to make a comparison with conventional devices.

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.

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.

Ultrasonic vs Drill Implant Site Preparation: Post-Operative Pain Measurement Through VAS, Swelling and Crestal Bone Remodeling: A Randomized Clinical Study

Background: Piezosurgery is a surgical procedure that is able to perform osteotomies by a micrometric and selective cut of the bone tissue. The objective of this investigation was to evaluate two different techniques; an ultrasonic device, and a drill approach for implant site preparation. Methods: A total of fifty patients were recruited for the randomized clinical trial to receive dental implants for fixed prosthetic restoration in the posterior mandible and were allotted to two groups. In Group A the implant site was prepared following a drilling technique, while in Group B the implant site was prepared using an ultrasonic device; moreover, the operative duration was recorded. Postoperative pain and swelling were evaluated at 1, 2, 4, and 6 days. The crestal bone resorption was measured at 3 months from implant placement by a three-dimensional tomography evaluation. Results: The findings suggest that osteotomies performed by an ultrasonic device cause less pain and swelling. On the other hand, the piezoelectric preparation was characterized by a significative increase in the operative time. No statistical differences in crestal bone resorption were evident in the two different approaches. Conclusions: According to the outcome of the study, ultrasonic implant bed preparation can be used with success in implantology and could be considered a suitable alternative to traditional drilling techniques for dental fixture placement.

Removal of external ear canal exostoses by piezo surgery: a novel technique

Background

External auditory canal exostoses are known to occur in patients who engage in cold-water sports. Although the majority of patients with exostosis remain asymptomatic, larger lesions can cause wax impaction, conductive hearing loss and predispose to recurrent otitis externa.

Objective

A novel technique is described of using a piezo saw to excise exostoses that are symptomatic. The piezo saw is used to perform various procedures, but its use in removing exostoses has not been described in the literature.

Conclusion

Excision of exostoses of the ear canal using a piezo saw is a safe technique and patients have a speedy recovery. This paper describes a new technique for removing exostoses.

Review on Otological Robotic Systems: Toward Microrobot-Assisted Cholesteatoma Surgery

Otologic surgical procedures over time have become minimally invasive due to the development of medicine, microtechniques, and robotics. This trend then provides an expected reduction in the patient's recovery time and improvement in the accuracy of diagnosis and treatment. One of the most challenging difficulties that such techniques face are precise control of the instrument and supply of an ergonomic system to the surgeon. The objective of this literature review is to present requirements and guidelines for a surgical robotic system dedicated to middle ear surgery. This review is particularly focused on cholesteatoma surgery (diagnosis and surgical tools), which is one of the most frequent pathologies that urge for an enhanced treatment. This review also presents the current robotic systems that are implemented for otologic applications.

Piezoelectric technology in otolaryngology, and head and neck surgery: a review

BACKGROUND

Piezoelectric technology has existed for many years as a surgical tool for precise removal of soft tissue and bone. The existing literature regarding its use specifically for otolaryngology, and head and neck surgery was reviewed.

METHODS

The databases Medline, the Cochrane Central Register of Controlled Trials, PubMed, Embase and Cambridge Scientific Abstracts were searched. Studies were selected and reviewed based on relevance.

RESULTS

Sixty studies were identified and examined for evidence of benefits and disadvantages of piezoelectric surgery and its application in otolaryngology. The technique was compared with traditional surgical methods, in terms of intra-operative bleeding, histology, learning curve, operative time and post-operative pain.

CONCLUSION

Piezoelectric technology has been successfully employed, particularly in otology and skull base surgery, where its specific advantages versus traditional drills include a lack of 'blunting' and tissue selectivity. Technical advantages include ease of use, a short learning curve and improved visibility. Its higher cost warrants consideration given that clinically significant improvements in operative time and morbidity have not yet been proven. Further studies may define the evolving role of piezoelectric surgery in otolaryngology, and head and neck surgery.

The Role of Piezoelectric Instrumentation in Rhinoplasty Surgery

BACKGROUND

In rhinoplasty surgery, management of the bony vault and lateral walls is most often performed with mechanical instruments: saws, chisels, osteotomes, and rasps. Over the years, these instruments have been refined to minimize damage to the surrounding soft tissues and to maximize precision.

OBJECTIVES

This article will present the evolution of the authors' current operative technique based on 185 clinical cases performed over an 19-month period using piezoelectric instrumentation (PEI).

METHODS

A two-part study of cadaver dissections and clinical cases was performed using PEI. Evolution of the authors' clinical technique and the operative sequence were recorded.

RESULTS

Thirty cadaver dissections and 185 clinical cases were performed using PEI, including 82 primary and 103 secondary cases. An extended subperiosteal dissection was developed to visualize all aspects of the open rhinoplasty including the osteotomies. Ultrasonic rhinosculpture (URS) was utilized in 95 patients to shape the bony vault without osteotomies. To date, 11 revisions (6%) have been performed. There were no cases of bone asymmetry, irregularity, or excessive narrowing requiring a revision.

CONCLUSIONS

Based on the authors' experience, adoption of PEI is justified and offers more precise analysis and surgical execution with superior results in altering the osseocartilaginous vault. With extensive exposure, surgeons can make an accurate diagnosis of bony deformity and safely contour the bones to achieve narrowing and symmetry of the bony dorsum. Stable osteotomies can be performed under direct vision with precise mobilization and control. As a result of PEI, the upper third of the rhinoplasty operation is no longer shrouded in mystery. LEVEL OF EVIDENCE 4: Therapeutic.

Piezosurgery in implant dentistry

Piezosurgery, or the use of piezoelectric devices, is being applied increasingly in oral and maxillofacial surgery. The main advantages of this technique are precise and selective cuttings, the avoidance of thermal damage, and the preservation of soft-tissue structures. Through the application of piezoelectric surgery, implant-site preparation, bone grafting, sinus-floor elevation, edentulous ridge splitting or the lateralization of the inferior alveolar nerve are very technically feasible. This clinical overview gives a short summary of the current literature and outlines the advantages and disadvantages of piezoelectric bone surgery in implant dentistry. Overall, piezoelectric surgery is superior to other methods that utilize mechanical instruments. Handling of delicate or compromised hard- and soft-tissue conditions can be performed with less risk for the patient. With respect to current and future innovative surgical concepts, piezoelectric surgery offers a wide range of new possibilities to perform customized and minimally invasive osteotomies.

The Reliability of the Ultrasonic Bone Scalpel in Cervical Spondylotic Myelopathy: A Comparative Study of 46 Patients

BACKGROUND

In patients with cervical spondylotic myelopathy (CSM), laminectomy is usually performed with a Kerrison rongeur or a high speed drill (HSD).The HSD, which is most often selected for laminectomy, may cause complications such as duratomy, thermal and mechanical neural injuries. With an ultrasonic bone scalpel (UBS), a less traumatic laminectomy can be performed in a shorter time. The aim of this study was to compare the results of laminectomies using HSD and UBS.

METHODS

Evaluation was made in 46 patients who were operated on for CSM. Cervical laminectomy was performed on 23 patients using the UBS (group I) and to 23 using the HSD (group II). A comparison was made of the 2 groups in respect of demographic characteristics, laminectomy levels, mean laminectomy duration, bleeding rates, and surgical complications.

RESULTS

In group I, the mean laminectomy time was 2.2 ± 0.4 min/level, mean blood loss was 180 mL, hospitalization was 3.0 ± 0.0 days, and C5 radiculopathy was seen in 1 patient. In group II, the mean laminectomy time was 7.4 ± 2.6 min/level, mean blood loss was 380 mL, hospitalization was 3.7 ± 1.3 days, C5 radiculopathy was seen in 1 patient and dura injuries in 3 patients. The recovery rate was determined as 47.6% in group I and 48.8% in group II.

CONCLUSIONS

For patients with CSM, laminectomy using the UBS provides a safe, rapid, and effective decompression with a lesser blood loss. The low rate of complications lessens the postoperative morbidity rates and shortens hospital stay.

Potential nerve damage following contact with a piezoelectric device

OBJECTIVES

The aim of the study was to assess the extent of the potential nerve damage following prolonged contact with a piezoelectric device.

METHODS

The study was conducted with 30 patients; all of the patients had cervical metastatic lymph nodes at levels II, III, and IV (N2b) and a negative evaluation for metastatic disease (MO). The patients underwent radical neck dissection. After its skeletonization, the spinal nerve was exposed directly to ultrasonic activation with a piezoelectric device for various times (5, 10, and 20 seconds) and with different inserts (OP3 insert and OT7 insert). The axonal damage was graded from 0 to 3 as follows: 0, no damage; 1, minor axonal damage; 2, severe axonal damage but not covering the entirety of the nerve fascicles; 3, severe axonal damage covering the entirety of the nerve fascicles.

RESULTS

Histologic examination showed no evidence of damage to the perineurium and axons after 5 and 10 seconds of exposure to ultrasonic activation with each insert.

CONCLUSIONS

Our histologic data highlight the selective action of the piezoelectric device, which reduces the risk of accidental nerve damage in otolaryngological bone surgery.

Hearing results after hypotympanotomy for glomus tympanicum tumors

OBJECTIVE

We postulate, that glomus tympanicum tumors (GTTs) may be safely removed without interference with the ossicular chain via a hypotympanotomy approach.

STUDY DESIGN

Prospective, nonrandomized anatomic and clinical study.

SETTING

Tertiary referral center.

PATIENTS

All 17 patients between 1989 and 2009 with GTTs without involvement of the lumen of the jugular bulb.

INTERVENTIONS

We used a modified hypotympanotomy approach. Our technique is a modification of the one first published by Shambaugh (1955). Pure-tone audiograms were performed in all patients. Preoperative and postoperative audiograms were modeled in a linear mixed model evaluating hearing threshold for air and bone conduction and air-bone gap at 500, 1,000, 2,000, and 3,000 Hz. In an effort to preserve the normal sound conducting apparatus and hearing, we used a retroauricular approach, exposing widely the jugular bulb, the carotid artery, the protympanum, and even the bony part of the Eustachian tube via a hypotympanotomy. Three formalin-fixed and one macerated temporal bones were dissected step by step under the operating microscope to demonstrate the approach in cadaver dissections.

MAIN OUTCOME MEASURE

To evaluate if GTTs can be completely resected without interference with the ossicular chain to improve conductive hearing loss.

RESULTS

We found a substantial improvement of hearing threshold after surgery at all frequencies in air conduction. For bone conduction, there was only a slight gain within random variation. The air-bone gap decreased significantly after surgery.

CONCLUSION

Our approach demonstrated a safe avenue for complete tumor removal without interference with the continuity of the ossicular chain.

Comparison of postoperative pain: piezoelectric device versus microdrill

Piezosurgery® is a recently developed system for cutting bone with microvibrations. The objective of this study was to compare the severity of pain over the first 10 postoperative days in a group of 70 patients who underwent intact canal wall mastoidectomy, with the piezoelectric device, and to compare the results with traditional method by means of microdrill (70 patients). The subjective perception of pain was evaluated on a scale from 0 to 10, such that 0 represented no pain and 10 represented maximum pain; the severity was recorded as null when the score was 0; slight, when it was 1-4; moderate, when it was 5-7; or severe, when it was 8-10. Compared with microdrill, the patients that underwent surgery with the piezoelectric device showed a significant (P < 0.05) lower postoperative pain on day 1 (52 vs. 26 patients presented a slight pain, 12 vs. 37 presented a moderate pain, and 6 vs. 7 presented a severe pain) and day 3 (68 vs. 44 patients presented a slight pain, 2 vs. 23 presented a moderate pain, and 0 vs. 3 presented a severe pain). These results highlight as the piezoelectric device is a safe and minimally invasive tool.

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.

Piezosurgery in oral and maxillofacial surgery

This review summarizes current knowledge and experience with piezosurgery, a promising, meticulous and soft tissue-sparing system for bone cutting, based on ultrasonic microvibrations. The main advantages of piezosurgery include soft tissue protection, optimal visibility in the surgical field, decreased blood loss, less vibration and noise, increased comfort for the patient and protection of tooth structure. To date it has been indicationed for use in oral and maxillofacial surgery, otorhinolaryngology, neurosurgery, ophthalmology, traumatology and orthopaedics. The main indications in oral surgery are sinus lift, bone graft harvesting, osteogenic distraction, ridge expansion, endodontic surgery, periodontal surgery, inferior alveolar nerve decompression, cyst removal, dental extraction and impacted tooth removal. In conclusion, piezosurgery is a promising technical modality for different aspects of bone surgery with a rapidly increasing number of indications throughout the whole field of surgery.

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.