Laser-assisted Cartilage Reshaping Research Articles

Current progress of laser-assisted cartilage reshaping for prominent ear

To summarize the current progress of laser-assisted cartilage reshaping (LACR) for prominent ear. The domestic and abroad article concerning the LACR in treatment of prominent ear was reviewed and analyzed. As a new technique, there were three types of LACR therapies that been used for prominent ear. LACR with the 1 064 nm Nd/YAG laser is painful and the penetration depth of the 1 064 nm Nd/YAG laser is greater than that of the 1540 nm Er/Glass laser which is caused more tissue injury. LACR with the 1 540 nm Er/Glass laser has high absorption by the ear cartilage and produce less injury to the surrounding tissue. Use of the CO 2 laser permitted cartilage reshaping combined with both vaporization and incisions, which complicates the technique, although, with low recurrence rate and definite effect. Insisting on wearing ear mold is the key to get satisfactory effectiveness for postoperative patients. The complications of LACR for prominent ear, such as the dermatitis, perforation of the skin, hematoma, or infection, should be noticed. Application of LACR for prominent ear just has a short period of time, limited number of cases, and few relevant literature reports. Its effectiveness needs to be further studied and clarified.

1064-nm Nd: YAG laser-assisted cartilage reshaping for treating ear protrusions.

Correction of prominent ears is a common plastic surgical procedure. The laser-assisted cartilage reshaping (LACR) technique for protruding ears was developed at the French National Institute of Health and Medical Research in Lille, France, using both the 1064- and 1540-nm wavelengths, with a view to simplifying the surgical procedure. Herein we report our results with the 1064-nm wavelength. Between 2008 and 2010, twenty-six 1064-nm LACR procedures in 14 patients were performed. Twelve patients received treatment to both ears, and 2 patients received treatment to one ear. Each procedure consisted of a single treatment session. The treatment consisted of laser irradiation of both sides of the helix with single pulses of 70 J/cm2. The beam diameter was 6 mm. Early and late complications were defined and reviewed for all patients. Satisfaction was assessed by patients using a visual analogue scale from 0 (unsatisfied) to 20 (highly satisfied). The superior and middle cephaloauricular distances were prospectively evaluated at 6 months after treatment. Complications included eight cases of localized skin burns and one case of dermatitis. The mean right/left superior and middle cephaloauricular distances were 10.5±1.5 mm/10.7±1.0 mm and 16.3±2.2 mm/16.3±2.8 mm, respectively, as compared to 17.5±2.9 mm/18.6±2.5 mm (P<0.01) and 24.5±2.6 mm/24.7±1.7 mm (P<0.01) before the operation. Mean patient satisfaction was 16.8/20±3.3. Despite promising results for cartilage reshaping, the 1064-nm LACR procedure often leads to skin burns and inflammatory tissue reaction after treatment. Moreover, LACR with the 1064-nm wavelength is painful and necessitates local anaesthesia. 4.

Laser-assisted cartilage reshaping for protruding ears: A review of the clinical applications.

In 2006, our institute reported the first clinical use of laser-assisted cartilage reshaping (LACR) for protruding ears. Since then, the technique has been developed and refined. This article reviews the literature on the clinical application of LACR. Literature review. A MEDLINE literature search was performed on LACR combined with cross-referencing. The period of search was 1993 to 2014. Search terms used were: laser, cartilage reshaping, protruding ears, LACR. Only seven clinical studies using three different wavelengths were found in the literature: 1,064 nm (Nd:YAG), 10,600 nm (CO2), and 1540 nm (Er:Glass). Clinical outcomes, laser wavelength and parameters, and patient satisfaction are discussed in each case. The success rate for ear reshaping achieved with LACR appears promising. The use of this noninvasive technique will increase in the near future.

Cartilage reshaping for protruding ears: A prospective long term follow‐up of 32 procedures

Correction of prominent ears is a common plastic surgical procedure. We introduced a new non-invasive laser-assisted cartilage reshaping (LACR) technique as an alternative to invasive surgical otoplasty. Since our first report in 2006, 32 LACR procedures in 17 patients have been performed at the Antoni De Gimbernat Foundation in collaboration with the French National Institute of Health and Medical Research (INSERM) U703. For 15 patients, the procedure was bilateral, for the remaining 2 patients LACR was performed only on one side. The treatment consisted of seven stacked pulses (3 ms, 2 Hz, 84 J/cm(2) cumulative fluence) applied using a 4-mm spot hand piece. Early and late complications were defined and reviewed for the whole series. Satisfaction was assessed by the patients using a visual analogue scale from 0 (unsatisfied) to 10 (highly satisfied). The superior and middle cephaloauricular distances were prospectively evaluated. Except for two cases of dermatitis, there were no early complications and no late complications (like keloids) in the series. The mean superior and middle cephaloauricular distances were, respectively, 12.3 ± 1.9 and 13.7 ± 1.6 mm compared to 17.8 ± 3.1 mm (p < 0.01) and 23.9 ± 1.9 mm (p < 0.01) before operation. Mean patient satisfaction was 8.6/10 with all patients reporting that they would be willing to undergo the procedure again, if required. LACR appears to be a safe and reproducible method for the treatment of protruding ears. Other applications of this technique, like laser assisted septal cartilage reshaping (LASCR) for septum deviation, have been recently described.

Laser assisted septal cartilage reshaping (LASCR): A prospective study in 12 patients

Occurring in one-third of the population, nasal obstruction is the most common complaint in an average rhinologic practice. The etiology is usually a deviation of the nasal septum, although other conditions, such as turbinate hypertrophy, can also cause nasal obstruction. Our team has already demonstrated that laser assisted cartilage reshaping can be used effectively for the correction of ear protrusion. This study aims to evaluate laser assisted septal cartilage reshaping (LASCR) to treat septal deviation. Between March 2009 and September 2009, 12 patients (8 males, 4 females-mean age: 23 years) underwent LASCR for treatment of septal deviation. The mean NOSE score was 11.6. Preoperative examination included rhinomanometry and nasal endoscopy to exclude inferior turbinate or adenoid hypertrophy. Both sides of the septum were irradiated using a 1,540 nm laser connected to a 4 mm spot handpiece with integrated cooling (fluence: 50 J/cm(2)). Contact cooling made the treatment tolerable, but topical anesthesia was still required. Immediately after the procedure, an internal splint was inserted into the nostril and kept for 7 days. The NOSE score was calculated at 1 week, 1 month, and 3 months post-procedure and a rhinomanometry was carried out at 3 months. The entire procedure took an average of 20 minutes. For all procedures, there were no lesions of the septal mucosa. Three months post-op, mean NOSE score improved from 11.6 to 5.3. Rhinomanometry assesses an increase in airflow (+19%) and improvement to air inflow resistance (-16%), confirming a subjective improvement. In seven adults, the expected septal reshaping was achieved. In five adults, incomplete septum reshaping was observed. In three patients it was correlated to anatomical variations: a thick septum in two cases and a long septum in one case. In the remaining two patients, it was due to insufficient fluence. In these cases, insufficient local anesthesia did not allow us to finish the procedure and the patients received a fluence of 30 J/cm(2) only. Those patients were re-treated at 3 months at 50 J/cm(2) fluence and all achieved suitable reshaping. LASCR is a safe and less morbid approach to surgical septoplasty. Since significant variability in the cartilaginous elements of the nose is the rule rather than the exception, some improvements in the technique are still required.

Carbon dioxide laser-assisted cartilage reshaping otoplasty: A new technique for prominent ears

Most otoplasty techniques are variations of suturing and sculpting concepts. Thick cartilage and its tricky everlasting reshaping is a difficult task in suture techniques. It is more difficult to predict and control the final result in cartilage sculpting techniques. Animal studies demonstrated temperature-dependent cartilage stress relaxation during laser application resulting in stable shape changes. The aim of this study was to describe a novel surgical technique of carbon dioxide laser-assisted cartilage reshaping (CO(2) LACR) otoplasty and to show its outcome. Prospective case series study. Sixteen patients with 32 prominent ears were involved prospectively. Carbon dioxide laser evaporation of the perichondrium and partial thickness of the medial surface of auricular cartilage and a pair of parallel laser incisions on scaphal and conchal lines were performed. The cartilage was fixed with absorbable Vicryl mattress sutures. Demographics, early and late postoperative outcomes, patients/parents and doctors satisfaction in the follow-up were studied. A total of 32 ears underwent repair. Patients ages ranged from 4 to 7 years (mean, 5.5 years). Average follow-up was 2.4 years. No cases required revision surgery. In late assessment 14 patients were pleased, two were satisfied, and no patients were unsatisfied. All patients had four to six of the six criteria for surgical success as defined by the study without complications. The present technique of CO(2) LACR otoplasty resulted in endurance of auricular appearance and symmetry, with good to satisfactory outcome to patient/parent.

Laser-Assisted Cartilage Reshaping (LACR) for Treating Ear Protrusions: A Clinical Study in 24 Patients

Protruding ears are the most common congenital ear deformity, with a frequency of 13.5%. Since 1845 and the first works of Dieffenbach, over 170 classical surgical methods have been proposed to correct it. We introduced laser-assisted cartilage reshaping (LACR) in 2004 as an alternative to invasive surgical otoplasty. Between January 2008 and June 2008, 24 patients underwent LACR for treatment of bilateral ear protrusion. Fourteen adults and ten children were treated (mean age = 16.0 years, range = 6-45 years). No anesthesia was used. Both sides of the entire helix and the concha were irradiated using a 1540-nm laser connected to a 4-mm spot handpiece with integrated cooling. Fluences varying from 70 up to 84 J/cm(2) were applied. Immediately after the irradiation, silicone elastomer was inserted inside the helix to give it the desired shape. After 3 minutes a solid mold was obtained. Patients were asked to keep this mold in place at all times with a bandage wrapped around the head for the first 3 weeks and then for an additional 3 weeks only during the night. A non-steroidal anti-inflammatory drug (NSAID) was prescribed to the patients for 3 days. At 1, 30, 60, and 90 days after the procedure, ears were checked and photographs were taken. Clinical follow-up at 1 year was obtained via direct patient contact or over the telephone. The treatment was well tolerated. No hematomas or skin necrosis occurred. Contact dermatitis was observed in four children and two adults as a result of inappropriate mold design. These patients stopped wearing the mold and the shape of their ear did not improve. For the remaining 18 patients (6 children and 9 adults), the expected ear reshaping was obtained (fluence was 84 J/cm(2)). For three other adults, incomplete reshaping of the ears was observed and can be correlated to a lower fluence (70 J/cm(2)). LACR, performed without any anesthesia, is a safe and less morbid approach to surgical otoplasty.

Correction of ear malformations by laser‐assisted cartilage reshaping (LACR)

Correction of ear malformations by laser‐assisted cartilage reshaping (LACR)

Correction of ear malformations by laser‐assisted cartilage reshaping (LACR)

Correction of ear malformations by laser‐assisted cartilage reshaping (LACR)

Raman microspectrometry of laser-reshaped rabbit auricular cartilage: preliminary study on laser-induced cartilage mineralization

Laser-assisted cartilage reshaping (LACR) is a relatively novel technique designed to noninvasively and permanently restructure cartilaginous tissue. It is believed that heat-induced stress relaxation, in which a temperature-mediated disruption of H2O binding is associated with conformational alterations in the proteoglycan and collagen-rich matrix, constitutes the underlying mechanism of LACR. Several reports have suggested that laser-mediated cartilage mineralization may contribute to the permanent shape change of laser-reshaped cartilage. In an effort to validate these results in the context of Er:glass LACR, we performed a preliminary Raman microspectrometric study to characterize the crystal deposits in laser-irradiated chondrocytes and extracellular matrix. For the first time, we identified intracellular calcium sulfate deposits and extracellular calcium phosphate (apatite) crystals in laser-reshaped rabbit auricular cartilage. Calcium carbonate deposits are localized in both irradiated and nonirradiated samples, suggesting that this mineral plays no role in conformational retention. In our discussion, we elaborate on the possible molecular and cellular mechanisms responsible for intra- and extracellular crystallization, and propose a novel hypothesis on the formation of apatite, inasmuch as the biological function of this mineral (providing structure and rigidity in bones and dental enamel) may be extrapolated to the permanent shape change of laser-irradiated cartilage.

Depth-resolved phase retardation measurements for laser-assisted non-ablative cartilage reshaping

Since polarization-sensitive optical coherence tomography (PS-OCT) is emerging as a new technique for determining phase retardation in biological materials, we measured phase retardation changes in cartilage during local laser heating for application to laser-assisted cartilage reshaping. Thermally-induced changes in phase retardation of nasal septal cartilage following Nd:YAG laser irradiation were investigated using a PS-OCT system. A PS-OCT system and infrared imaging radiometer were used to record, respectively, depth-resolved images of the Stokes parameters of light backscattered from ex vivo porcine nasal septal cartilage and radiometric temperature changes following laser irradiation. PS-OCT images of cartilage were recorded before (control), during and after laser irradiation. From the measured Stokes parameters (I, Q, U and V), an estimate of the relative phase retardation between two orthogonal polarizations was computed to determine birefringence in cartilage. Phase retardation images of light backscattered from cartilage show significant changes in retardation following laser irradiation. To investigate the origin of retardation changes in response to local heat generation, we differentiated two possible mechanisms: dehydration and thermal denaturation. PS-OCT images of cartilage were recorded after dehydration in glycerol and thermal denaturation in heated physiological saline. In our experiments, observed retardation changes in cartilage are primarily due to dehydration. Since dehydration is a principal source for retardation changes in cartilage over the range of heating profiles investigated, our studies suggest that the use of PS-OCT as a feedback control methodology for non-ablative cartilage reshaping requires further investigation.

Stress Relaxation of Porcine Septal Cartilage During Nd:YAG (λ=1.32 μm) Laser Irradiation: Mechanical, Optical, and Thermal Responses

Laser-assisted cartilage reshaping is mediated by thermally induced stress relaxation, and may be used to alter cartilage morphology for reconstructive surgical procedures in the upper airway and face without carving, morselizing, or suturing. Internal stress σ(t), integrated backscattered light intensity I(t) from a He-Ne probe laser (λ=632.8 nm), and radiometric surface temperature Sc(t) were measured during the reshaping of porcine nasal septal cartilage using a pulsed Nd:YAG laser (λ=1.32 μm). Internal stress and integrated backscattered light intensity were observed to increase, plateau, and then decrease in similar ways during laser irradiation. The plateau region occurred when the cartilage front surface temperature approached 65 °C. I(t) was utilized in a feedback control procedure to reshape cartilage specimens from a flat to a curved geometry. Immediately following laser irradiation, the tissues were rehydrated in normal saline for 15 min while wrapped around a small dowel. A stable shape change was retained for 21 days while the specimens were stored in normal saline at 5 °C. The backscattered light intensity signal mirrors underlying changes in internal stress, and further rate of change or slope of I(t) is nearly zero when the surface temperature reaches about 65 °C. Measurements of I(t) (or, equivalently, the fractional change in integrated backscattered light intensity ΔI(t)/I0) may be used to control the process of laser-assisted cartilage reshaping and minimize nonspecific thermal injury due to uncontrolled heating. © 1998 Society of Photo-Optical Instrumentation Engineers.

Measurement of radiometric surface temperature and integrated backscattered light intensity during feedback-controlled laser-assisted cartilage reshaping

Cartilage undergoes characteristic mechanical stress relaxation following laser irradiation below the ablation threshold. Porcine auricular cartilage (1–2 mm thickness) was irradiated with a Nd:YAG laser (λ=1.32 μm) at two power levels (W/cm2). Surface temperature (S c (t) (°C)) (monitored using a single element HgCdTe infrared detector, 10-14 μm spectral range), and integrated back scattered light intensityI(t) were measured during laser irradiation. A HeNe laser beam (λ=632.8 nm) was incident on the back surface of the cartilage specimen and fractional integrated backscattered light intensity was measured using an integrating sphere anda silicon photodiode. Laser irradiation (5.83 W/cm2, 50 Hz pulse repetition rate (PRR)) continued until surface temperature reached approximately 70°C, during which cartilage mechanical stress relaxation was observed. Integrated back scattered light intensity reached a plateau at about 70°C). At higher laser power (39.45 W/cm2, 50 Hz PRR), a feedback-controlled cryogen spray was used to maintain surface temperature below 50°C. A similar plateau response was noted in integrated backscattered light intensity. This signal may be used to optimise the process of stress relaxation in laser cartilage reshaping. Several clinical applications involving reconstructive surgery are proposed.