Optimal surgical timing for ear reconstruction with autologous cartilage: Analysis of the computed tomography scan characteristics of the ribs.

BACKGROUND: The approach to constructing the cartilage framework for ear reconstruction is sufficiently established. However, there is still no consensus about the age of initiation of surgical treatment. This study aims to assess the development and growth of the costal cartilage to determine the best age to perform ear reconstruction surgery. METHODS: Out of 107 patients, we used presurgical treatment data for 40 patients and medical records for 67 patients aged 5-40. Computed tomography (CT) scans were performed, and average parameters were calculated (length, width, thickness, cartilage density, and standard deviation in Hounsfield units) of the cartilaginous part of the 6th, 7th, 8th, and 9th ribs. RESULTS: The required values were reached at 9-10 years old. CONCLUSION: The criteria for starting surgical treatment in the Russian population was determined by the width of the 6th-7th ribs synchondrosis, which must be equal to the width of a healthy auricle, and the length of the 8th rib should be longer than 9 cm. Therefore, the optimal age for ear reconstruction with autologous costal cartilage is 10 years and older. However, reconstruction can be made earlier in specific cases, according to height and weight and the preoperative CT scan.

Ultrasonography of auricular cartilage is a potential tool for diagnosing relapsing polychondritis and monitoring disease activity.

AIM: To assess the clinical utility of ultrasonography in the diagnosis and monitoring of disease activity in relapsing polychondritis (RP). METHODS: Auricular and nasal chondritis of 6 patients with RP were assessed by ultrasonography before treatment initiation. Changes in the ultrasonographic and clinical findings and serum inflammatory markers were longitudinally assessed. Ultrasonography was also performed in 6 patients with repeat ear trauma, 6 patients with auricular cellulitis and 6 healthy controls for comparison among groups. RESULTS: In all cases of RP, ultrasonographic findings before treatment revealed low-echoic swollen auricular and nasal cartilage and perichondral soft-tissue with increased power Doppler signals (PDS) corresponding to biopsy findings. After 2-month treatment with prednisolone (PSL) combined with methotrexate, clinical and serum inflammatory markers were completely resolved. Although swollen perichondral soft-tissue, cartilage and PDS on auricular ultrasonography were also significantly improved, PDS remained in 2 of 6 cases, which showed flare early after tapering PSL. Finally, ultrasonographic findings of RP were substantially differentiated between patients with repeat trauma and cellulitis and healthy controls based on the thickness of soft tissue around the cartilage, PDS and subperichondral serous effusion. CONCLUSION: Assessment of RP lesions by ultrasonography is useful for the evaluation of cartilaginous lesions and monitoring of disease activity, especially when considering the treatment response and the timing of drug tapering.

Robot-Automated Cartilage Contouring for Complex Ear Reconstruction: A Cadaveric Study.

OBJECTIVES/HYPOTHESIS: Auricular reconstruction requiring manual contouring of costal cartilage is complex and time consuming, which could be facilitated by a robot in a fast and precise manner. This feasibility study evaluates the accuracy and speed of robotic contouring of cadaver costal cartilage. METHODS: An augmented robot with a spherical burr was used on cadaveric rib cartilage. Using a laser scanner, each rib section was converted to a three-dimensional model for preoperative planning. A model ear was also scanned to define a carving path for each piece of cartilage. After being contoured, each specimen was compared against the preoperative plan utilizing deviation maps to analyze topographic accuracy. Contouring times of the robot were compared with 13 retrospectively reviewed cases (2006-2017) by an experienced surgeon. RESULTS: Scanning the cartilage sections took 24.8 ± 6.8 seconds. Preoperative processing took an additional 29.9 ± 8.9 seconds for the preparation of the contouring path. Once the path was prepared, the robot contoured the specimens with a root mean square error of 0.54 mm and a mean absolute deviation of 0.40 mm. The average time to contour the specimens with the robot was 13 ± 2 minutes compared to 71 ± 6 minutes for the manual contouring in the reviewed cases. CONCLUSIONS: The accuracy of the robotic system was high, with submillimeter deviations from the preoperative plan. The robot required <20% of the contouring time compared to the experienced surgeon. This represents a fast and accurate alternative to hand-contouring costal cartilage grafts for auricular reconstruction. Laryngoscope, 131:1002-1007, 2021.

Hybrid Three-Dimensional-Printed Ear Tissue Scaffold With Autologous Cartilage Mitigates Soft Tissue Complications.

OBJECTIVES/HYPOTHESIS: To analyze the use of highly translatable three-dimensional (3D)-printed auricular scaffolds with and without novel cartilage tissue inserts in a rodent model. STUDY DESIGN: Preclinical rodent animal model. METHODS: This prospective study assessed a single-stage 3D-printed auricular bioscaffold with or without porcine cartilage tissue inserts in an athymic rodent model. Digital Imaging and Communications in Medicine computed tomography images of a human auricle were segmented to create an external anatomic envelope filled with orthogonally interconnected spherical pores. Scaffolds with and without tissue inset sites were 3D printed by laser sintering bioresorbable polycaprolactone, then implanted subcutaneously in five rats for each group. RESULTS: Ten athymic rats were studied to a goal of 24 weeks postoperatively. Precise anatomic similarity and scaffold integrity were maintained in both scaffold conditions throughout experimentation with grossly visible tissue ingrowth and angiogenesis upon explantation. Cartilage-seeded scaffolds had relatively lower rates of nonsurgical site complications compared to unseeded scaffolds with relatively increased surgical site ulceration, though neither met statistical significance. Histology revealed robust soft tissue infiltration and vascularization in both seeded and unseeded scaffolds, and demonstrated impressive maintenance of viable cartilage in cartilage-seeded scaffolds. Radiology confirmed soft tissue infiltration in all scaffolds, and biomechanical modeling suggested amelioration of stress in scaffolds implanted with cartilage. CONCLUSIONS: A hybrid approach incorporating cartilage insets into 3D-printed bioscaffolds suggests enhanced clinical and histological outcomes. These data demonstrate the potential to integrate point-of-care tissue engineering techniques into 3D printing to generate alternatives to current reconstructive surgery techniques and avoid the demands of traditional tissue engineering. LEVEL OF EVIDENCE: NA Laryngoscope, 131:1008-1015, 2021.

3D hybrid printing platform for auricular cartilage reconstruction.

As scaffolds approach dimensions that are of clinical relevance, mechanical integrity and distribution becomes an important factor to the overall success of the implant. Hydrogels often lack the structural integrity and mechanical properties for use in vivo or handling. The inclusion of a structural support during the printing process, referred to as hybrid printing, allows the implant to retain structure and protect cells during maturation without needing to compromise its biological performance. In this study, scaffolds for the purpose of auricular cartilage reconstruction were evaluated via a hybrid printing approach using methacrylated Gelatin (GelMA) and Hyaluronic acid (HAMA) as the cell-laden hydrogel, Polycaprolactone (PCL) as structural support and Lutrol F-127 as sacrificial material. Furthermore, printing parameters such as nozzle diameter, strand spacing and filament orientation scaffolds were investigated. Compression and bending tests showed that increasing nozzle sizes decrease the compressive modulus of printed scaffolds, with up to 82% decrease in modulus when comparing between a 400 µm and 200 µm sized nozzle tip at the same strand spacing. On the contrary, strand spacing and orientation influences mainly the bending modulus due to the greater porosity and changes in pore size area. Using a 400 µm sized nozzle, scaffolds fabricated have a measured compression and bending modulus in the range similar to the native cartilage. The viability and proliferation of human mesenchymal stem cells delivered within the bioink was not affected by the printing process. Using results obtained from mechanical testing, a scaffold with matching mechanical properties across six distinct regions mimicking the human auricular cartilage can be completed in one single print process. The use of PCL and GelMA-HAMA as structural support and cell-laden hydrogel respectively are an excellent combination to provide tailored mechanical integrity, while maintaining porosity and protection to cells during differentiation.

Relapsing polychondritis associated with psoriasis vulgaris successfully treated with adalimumab: A case report with published work review.

Relapsing polychondritis (RP) is a rare autoimmune-mediated disease characterized by inflammation involving cartilaginous tissues. We report here a case of RP in a 38-year-old Japanese man with 13-year duration of psoriasis vulgaris treated with topical steroids and vitamin D3 . The patient presented with tender swelling and erythema of both auricles, and the antibody to type II collagen was detected. The biopsy specimen revealed a dense mixed cell infiltration over the auricular cartilage. We reviewed eight cases with the association of RP and psoriasis, and in all cases the clinical course of psoriasis did not correlate with that of RP. The severity of RP was mild in the majority of cases, and our case was unique in that the patient had no joint symptoms. Adalimumab treatment was effective for both RP and psoriasis. Fat-suppressed contrast-enhanced magnetic resonance imaging was beneficial, not only to demonstrate subclinical inflammation in the nasal septum, but also to subjectively assess the improvement of RP.

Prevalence of the petrified ear: a computed tomographic study.

The petrified ear is characterized by calcifications or ossifications of the cartilaginous parts of the outer ear. It is described as a rare finding, but the prevalence of this finding is unclear. In a retrospective analysis of 200 computed tomographic scans of the head, 39 patients showed ossifications/calcifications of the cartilaginous parts of the outer ear (19.5%). These affected the cartilage of the auricle in 13 patients (6.5%), the cartilaginous parts of the external auditory channel in 25 (12.5%) and in one patient both (0.5%). All ossifications/calcifications were incidental findings in our series. Contrary to most authors, auricular ossifications/calcifications per se seem to be a common finding, but symptoms due to a petrified ear seem to be rare. To establish proper differential diagnosis, radiologists and otorhinolaryngologists should be aware of these findings.

The effect of "minimally invasive transfer of angiosomes" on vascularization of prefabricated/prelaminated tissues.

Prefabrication and prelamination are experimental and clinical applications of reconstructive surgery and inspired the vascularization challenge of engineered tissues. The purpose of this study is to test the efficiency of "minimally invasive transfer of angiosomes" to enhance the vascularization of the final construct during prefabrication and prelamination. Fifteen rabbits were used for this study. Three of the animals were used in a pilot study to develop the protocol. During the study, thoracodorsal and lateral thoracic vascular pedicles on each side constituted 4 study groups. The pedicles were prepared to simulate prelamination with and without transfer of angiosomes, and prefabrication with and without transfer of angiosomes. In all of the groups, a 10 x 15 mm auricular cartilage graft was used as the construct to be vascularized. After 2 weeks, vascularization of the grafts was evaluated by means of microangiography and histology. Results indicate that both prelamination and prefabrication with transfer of angiosomes displayed better vascularization, both qualitatively and quantitatively. However, prelamination with transfer of angiosomes group displayed distinct statistical superiority. The results suggest that minimally invasive transfer of angiosomes coupled with the procedure significantly increases the induction of angiogenesis during prelamination and prefabrication.

Sonography of the ear pinna.

OBJECTIVE: This study was undertaken to assess the scope of sonography for the diagnosis of diseases of the external ear. METHODS: We developed a description of the sonographic anatomy of the normal ear pinna, including the thickness of the normal cartilage and lobule, through systematic scanning of the external ears of 11 healthy volunteers (2 male and 9 female), and reviewed clinical cases with pathologic entities. RESULTS: Reproducible and recognizable images were collected from normal as well as pathologic cases of the external ear. Images are presented for reference. CONCLUSIONS: Sonography permits good visualization of the internal structure, including the cartilage, and it is possible to use sonography as a method of study to differentiate between inflammation, vascular lesions, and tumors.

Correlation between projection of the ear, the inferior crus, and the antihelical body: analysis based on computed tomography.

We investigated the correlation between projection of the ear and the antihelical folding angle to clarify which portion of the antihelix should be corrected in reconstruction of prominent ears using computed tomograms of 15 ears in 11 patients with fractures of the facial bones. The angle of the scaphotriangular fossa indicating the superior crus, cymba conchae-triangular fossa angle indicating the inferior crus, and the scaphoconchal angle indicating the antihelical body were measured. There was no relation between the cranioauricular angle and the angle of the scaphotriangular fossa. However, there were significant relations between the cranioauricular angle and the cymba conchae-triangular fossa angle, and the cranioauricular and scaphoconchal angles, which suggests that emphasis should be placed on reconstruction of the inferior crus and antihelical body when prominent ears are being corrected.