Piezosurgery prevents brain tissue damage: an experimental study on a new rat model

Minimizing Invasiveness in Neurosurgical Osteotomies: A Comparative Histomorphometric Study of Piezoelectric Craniotomy versus High-Speed Drill

BACKGROUND

Piezoelectric bone cutting has gained popularity in neurosurgical osteotomies due to perceived lower trauma compared to rotary instruments. However, histological confirmation of its decreased aggressiveness is lacking, hindering conclusive proof. This study compares the bony and neuro-meningeal invasiveness of piezoelectric craniotomy with high-speed drill techniques.

METHODS

Histological data from 21 sheep undergoing piezoelectric craniotomy and 19 sheep subjected to high-speed electric drill craniotomy were compared. Piezoelectric craniotomy utilized a 0.35 mm micro saw titanium nitride coated. Outcome parameters included the detection of the "smear layer," average osteoblast count per high-power field, and residual bone matrix for bony invasiveness assessment. Parameters for meningeal and brain parenchymal invasiveness included pachymeningeal and leptomeningeal injury, gliosis, and histiocytic infiltration. Statistical significance was determined at P < 0.05.

RESULTS

Results showed the Piezo group had fewer frequent smear layers (P <0.001), higher residual bone matrix (P < 0.05), and greater osteoblast counts per high-power field (P < 0.05). Additionally, the Piezo group exhibited lower rates of leptomeningeal injury, cerebral gliosis, and histiocytic infiltration (P < 0.05).

CONCLUSIONS

Piezoelectric craniotomy preserves residual osteoblast viability and leptomeningeal integrity while demonstrating lower rates of thermally induced gliosis and histiocytic infiltration compared to high-speed drills. This suggests the piezoelectric osteotome's minimal invasiveness in bone, meningeal, and brain tissue.

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.

Minimal Invasive Piezoelectric Osteotomy in Neurosurgery: Technic, Applications, and Clinical Outcomes of a Retrospective Case Series

Objective: To report the physical and technical principles, clinical applications, and outcomes of the minimal invasive piezoelectric osteotomy in a consecutive veterinary neurosurgical series.

METHODS

A series of 292 dogs and 32 cats underwent an osteotomy because a neurosurgical pathology performed with a Mectron Piezosurgery^® bone scalpel (Mectron Medical Technology, Genoa, Italy) was retrospectively reviewed. Efficacy, precision, safety, and blood loss were evaluated intraoperatively by two different surgeons, on a case-by-case basis. Postoperative Rx and CT scans were used to assess the selectivity and precision of the osteotomy. A histological study on bony specimens at the osteotomized surface was carried out to evaluate the effects of piezoelectric cutting on the osteocytes and osteoblasts. All the patients underwent a six-months follow-up. A series of illustrative cases was reported.

RESULTS

All the osteotomies were clear-cut and precise. A complete sparing of soft and nervous tissues and vasculature was observed. The operative field was blood- and heat-free in all cases. A range of inserts, largely different in shape and length, were allowed to treat deep and difficult-to-reach sites. Two mechanical complications occurred. Average blood loss in dogs' group was 52, 47, and 56 mL for traumatic, degenerative, and neoplastic lesions, respectively, whereas it was 25 mL for traumatized cats. A fast recovery of functions was observed in most of the treated cases, early on, at the first sixth-month evaluation. Histology on bone flaps showed the presence of live osteocytes and osteoblasts at the osteotomized surface in 92% of cases.

CONCLUSIONS

Piezosurgery is based on the physical principle of the indirect piezo effect. Piezoelectric osteotomy is selective, effective, and safe in bone cutting during neurosurgical veterinary procedures. It can be considered a minimal invasive technique, as it is able to spare the neighboring soft tissues and neurovascular structures.

Observational Study on the Preparation of the Implant Site with Piezosurgery vs. Drill: Comparison between the Two Methods in terms of Postoperative Pain, Surgical Times, and Operational Advantages

Purpose

Recent advances show that ultrasonic implant site osteotomy is related to a decreased trauma and a better postoperative healing of the surgical site when compared to traditional drilling techniques. The micrometric bone cutting control and the operative advantages related to the piezoelectric approach are also characterized by a learning curve for the clinician in surgical practice and an increased operative duration of the procedure. The aim of this investigation is to compare the operative time, the postoperative pain, and the amount of painkillers taken by the patient during the healing period.

Methods

A total of 65 patients were treated at the Unit of Oral Surgery (Department of Medical Sciences, Surgery and Health, University of Trieste, Italy) using a split mouth model: 75 drill-inserted implants (G1) and 75 piezoelectric device-inserted implants (G2) were placed. The Visual Analogue Scale (VAS) was performed to evaluate the postoperative pain at 15 days from surgery. The operative time and frequency of intake of painkillers were measured.

Results

The G1 and G2 groups showed a significant difference with a higher use of painkillers observed for G1. The G2 patients showed a lower level of pain (VAS) at all experimental times between 8 hours to 7 days (p < 0.01) postsurgery. At 15 days, the pain levels were similar for both groups. No differences were found in site preparation duration between the study groups.

Conclusions

The evidence supports the application of the piezoelectric approach compared to the drill's osteotomy as a useful technique for implant site preparation. This trial is registered with NCT03978923.

[Comparison of piezoelectric and conventional osteotomy in rhinoplasty : A systematic review]

BACKGROUND

Postoperative periorbital edema and ecchymosis after rhinoplasty are mainly caused by the osteotomy with hammer and chisel. The introduction of piezoelectric surgery could lead to a better early postoperative outcome due to improved preservation of soft tissues. The aim of this systematic review was to evaluate the methods and results of studies comparing conventional osteotomy to piezoelectric osteotomy.

METHODS

A systematic literature search was conducted in the PubMed/MEDLINE and Google Scholar databases. In the primary selection, all studies on the comparison of conventional and piezoelectric osteotomies with regard to postoperative periorbital edema and/or ecchymosis were identified. Secondary selection included only study designs with a control group.

RESULTS

Primary selection resulted in 15 thematically relevant publications with a notable increase in annual publications between 2007 and 2017. Six studies with control groups were selected secondarily. Qualitatively and methodologically, the studies were very heterogeneous. The results of five of the six studies indicated a significant advantage of piezo technology compared to conventional osteotomy. Only in one study was no significant difference found in the investigated postoperative outcome.

CONCLUSION

Piezoelectric osteotomy resulted in a reduced propensity for postoperative edema and ecchymosis compared to the conventional osteotomy technique with a chisel. At this time, the results should be regarded as a trend. A definite recommendation favoring piezoelectric osteotomy cannot be made until more studies with higher patient numbers become available.

Piezo High Accuracy Surgical Osteal Removal (PHASOR): A Technique for Improved Cranial Window Surgery in Mice

Multiphoton microscopy has been widely adapted for imaging neurons in vivo. Repeated imaging requires implantation of a cranial window or repeated thinning of the skull. Cranial window surgery is typically performed with a high speed rotary drill, and many investigators find it challenging to prevent the drill from damaging the delicate dura and blood vessels. Extensive training and practice is required to remove the bone without damage to underlying tissue and thus cranial window surgery can be difficult, time consuming, and produce tissue damage. Piezoelectric surgery, which is extensively used for maxillofacial and dental surgery, utilizes ultrasonic vibrations to remove bone without damaging soft tissues. We have developed a method applying piezoelectric surgery to improve cranial window surgery in mice in preparation for multiphoton imaging. Comparisons within our lab find that the method requires less surgery time and has a lower average rate of complications due to dural bleeding than cranial window surgery with a rotary drill.

Morphological characteristics of osteotomies using different piezosurgical devices. A scanning electron microscopic evaluation

PURPOSE

The objective of this study was to compare morphological characteristics of osteotomies performed by 6 Piezosurgical devices.

MATERIALS AND METHODS

The 6 Piezosurgical units were: (a) Piezotom, (b) SurgySonic, (c) Piezon Master Surgery, (d) VarioSurg, (e) Surgybone, and (f) Piezosurgery 3. Osteotomies on 9 freshly slaughtered cattle ribs (2 cuts by each unit, per rib) from the cortical (first cut at 5 mm) to the cancellous (second cut at 3 mm) bone layer were performed. The osteotomy margins were compared using scanning electron microscopy analysis. The cutting areas, osteotomy bottoms, and osteotomy margins were analyzed morphologically. Statistical evaluation of the 2 cuts regarding the design of the tips (a-d: tapered tool shanks, f: parallel tool shank) was performed by an unpaired t test.

RESULTS

Morphological characteristics were different for each Piezosurgical unit and each examined area. A significant difference (P = 0.0209) of the upper width of the first cut between tapered and parallel tips was shown.

CONCLUSIONS

The morphological characteristics of the produced Piezosurgical osteotomies vary and depend on the Piezosurgical unit and tip.

Ultrasonic aesthetic cranioplasty

The management of frontal bone injury is an important issue, and inappropriate management of such injuries may give rise to serious complications. Piezosurgery is a technique used to perform safe and effective osteotomies using piezoelectric ultrasonic vibrations. This instrument allows a safe method for osteotomy of the cranial vault in close proximity to extremely injury-sensitive tissue such as the brain. After a wide review of the literature, the authors present this technical report, introduce the use of piezosurgery to perform a safe "slim-osteotomies" for treatment of posttraumatic frontal bone deformities, and suggest the use of this instrument for aesthetic recontouring of the craniofacial skeleton.

Piezoelectric surgery -a novel technique for laminectomy

OBJECTIVE

Piezoelectric surgery is a novel technology that allows for the osteotomy of mineralized tissue with less risk of damaging underlying soft tissue structures. This selective cutting increases the safety of osteotomies performed in close vicinity to delicate structures such as dura mater, blood vessels, and neural tissue. This study aimed to develop and describe the technique of piezoelectric surgery for dorsal laminectomy and to assess its clinical safety in normal sheep.

METHODS

A piezoelectric, dorsal laminectomy technique was developed using ovine cadavers. Following technique development, six live sheep underwent a piezoelectric (n = 6) two-level dorsal laminectomy at L2-L3 and L4-L5 (PiezoL2-3,4-5), and another 30 live sheep underwent a three-level laminectomy at L1, L3, and L5 (PiezoL1,3,5) for a total of 102 laminectomy sites. Surgery time and postoperative complications were recorded.

RESULTS

Dorsal laminectomy was safely and accurately performed in 35/36 study sheep using a Piezoelectric surgical instrument. No dural tears were noted in any animal. Non-ambulatory paraparesis in one study sheep (PiezoL1,3,5) led to euthanasia at 48 hr and only mild epidural hematoma was noted on necropsy. No other major postoperative complications were observed in any of the animals. Subjectively, PiezoL was easy to perform and with a rapid learning curve. Mean surgery time was 105 min (range: 75-165 min; median: 97.5) for PiezoL2-3,4-5 and 93 minutes (range 55-100 min; median: 67.5) for PiezoL1,3,5.

CONCLUSIONS

Based on our study, PiezoL is considered a safe and viable technique for performing ovine dorsal laminectomy in the preclinical research setting.

Use of an ex vivo canine ventral slot model to test the efficacy of a piezoelectric cutting tool for decompressive spinal surgery

OBJECTIVE

To test the efficacy of a piezoelectric instrument (PI) for bone removal during ventral slot surgery.

STUDY DESIGN

Ex vivo feasibility study.

SAMPLE POPULATION

Cadaveric canine cervical spinal specimens (n = 3; C1-7; C1-T1; C2-T1).

METHODS

The spinal cord of each explanted spinal unit was replaced with a saline-filled latex condom. In 8 disc spaces, ventral slot surgery was performed using a previously reported technique. Bone removal was achieved using a motorized burr (MB). In 8 disc spaces, bone was removed via en bloc ostectomy with a PI that selectively cuts mineralized tissue. Surgical duration and operating field visibility were recorded. Rupture of the fluid filled condom was used as a measure of iatrogenic collateral trauma. Computed tomography was used to measure ventral slot morphometry.

RESULTS

Mean surgical duration for PI (23.4 minutes) was significantly shorter than for MB (34.1 minutes; P = .049). Using a 4 point Likert scale (4 = excellent, 3 = good, 2 = fair, 1 = poor), median visibility score was significantly higher for PI (2) than for MB (1; P = .03). The condom burst twice (1MB, 1PI) during elevation of the dorsal longitudinal ligament; there was no significant difference between techniques for incidence of collateral trauma (P = .99). Regardless of surgical technique, there was a bias in slot deviation towards the right (i.e., the surgeon's left; P = .021).

CONCLUSIONS

The PI allowed completion of ventral slots in a significantly shorter time, without an increased incidence of iatrogenic trauma. The right-handed surgeon showed a left-sided aiming bias, regardless of surgical technique.

Latest trends in craniomaxillofacial surgical instrumentation

PURPOSE OF REVIEW

To review the past year's literature regarding recent innovations in surgical instrumentation for craniomaxillofacial surgery.

RECENT FINDINGS

Current advances in surgical instrumentation have led to many improvements in the field, allowing greater visualization and precision both before and during procedures. One of the common goals is to achieve excellent outcomes with minimal complications, while at the same time minimizing invasiveness of surgery. Highlighted innovations include greater capacities for acquisition of data, leading to improved imaging modalities and expansion of computer-assisted surgical techniques; continued developments in biomaterials used in various reconstructions; and novel uses of bone cutting and bone fixation instrumentation.

SUMMARY

Technology in the field of craniomaxillofacial surgery is developing rapidly, leading to novel instrumentation being utilized across a broad spectrum of areas. Published data have been encouraging to date, indicating an ever increasing adaptation of these innovations in clinical practice. Future efforts need to focus on cost-benefit analysis and constructing larger-scale studies to better understand effectiveness and patient outcomes.

Ultrasonic orthognathic surgery: enhancements to established osteotomies

The use of a novel ultrasonic osteotome enabled the authors to modify well-established orthognathic osteotomies to more favourably address the anatomy. For this purpose, they utilized a powerful ultrasonic device with tissue-selective cutting characteristics that was originally developed for spinal osteotomies and nerve decompression (BoneScalpel™ by Misonix Inc., Farmingdale, NY, USA). Its straight ultrasonic blade was adapted for dual action, and a soft protective element was added. The product modifications and the related changes regarding maxillary and mandibular osteotomies are explained in detail. A series of 83 patients underwent orthognathic surgery with the BoneScalpel ultrasonic osteotome. All osteotomies within this study group were performed purely ultrasonically and without the auxiliary use of reciprocating saws or rotary burrs. The complications, alveolar nerve impairment and bad splits were assessed. To assess the quality of the lingual osteotomies and pterygomaxillary separation, three-dimensional scanning was performed on 30 patients. In conclusion, the BoneScalpel™ ultrasonic osteotome enabled improved control over orthognathic osteotomies and resulted in significant reductions in the occurrence of nerve impairment and bad splits.

Piezosurgery for osteotomies in orbital surgery: Our experience and review of the literature

INTRODUCTION

Piezoelectric bone surgery, simply known as Piezosurgery(®), is a new promising technique for bone cutting based on ultrasonic microvibrations that allows to perform precise and thin osteotomies with soft tissue sparing.

PRESENTATION OF CASE

A 45-years-old woman presenting with progressive left ocular pain, diplopia on the lateral left gaze, and visible exophthalmos was admitted to our department. CT scan and MRI images documented a left supero-lateral orbital lesion. A left lateral orbitotomy using the piezoelectric scalpel was performed. The tumour (lacrimal gland lymphoma) was completely removed with no injuries to the orbital structures and with a perfect realignment of the bone stumps.

DISCUSSION

High powered pneumatic osteotome are commonly used to perform craniotomies. Large bone cutting groove and high temperatures developing at the contact site could produce an uneasy bone healing. The use of a piezoelectric scalpel allows to realize precise and thin osteotomies, facilitating craniotomy's borders ossification and avoiding injuries to non-osseous structures.

CONCLUSION

Widely used in Oral and Maxillofacial Surgery, Piezosurgery(®) can also be useful in neurosurgical approaches in order to obtain a faster bone flap re-ossification, a better aesthetic result, and a lower risks of dural layer and soft tissue damage.