BACKGROUND AND OBJECTIVES

Mouth retractors are essential in ensuring efficient yet safe exposure of the oral cavity and oropharynx. However, when applied improperly or haphazardly, retractors can cause tissue injuries and compromise patient safety. In addition, there are gaps in the usability of existing designs. This study aimed to identify the issues encountered by otorhinolaryngology surgeons in the use of commercially available mouth retractors, design and fabricate an improved retractor, and explore the use of additive manufacturing (popularly known as 3D printing) for retractor prototyping.

The study used the United States Food and Drug Administration (US FDA) Design Control as its framework. End-user requirements from otorhinolaryngologists were collected through key informant interviews. Results were organized into a Design Input template which was used to guide the design and development process. Prototype designs were iteratively created using computer-aided design software and 3D printing. Once design specifications were satisfied, a beta prototype was fabricated and given to another cohort of otorhinolaryngologists. The participants assessed the usability of the beta prototype. System Usability Scale (SUS) was used to quantify participant's feedback.

Five designs were created in the course of the study. The final prototype was fabricated using a Stereolithography (SLA) 3D printer. Several features were developed to address user requirements. The primary modification was to make the retractor modular to facilitate easier and shorter mounting and assembly. Gingival injury was addressed with the replacement of the maxillary alveolus hook with support bars. Five participants evaluated the beta prototype which received a mean SUS score of 75, well above the 50th percentile threshold.

This study demonstrates the applicability of the US FDA Design Control Process in the local setting to improve the mouth retractor design. Clinical and ergonomic issues were identified and design solutions were proposed and some have been implemented in a low-fidelity prototype. Results of the small-scale usability test suggest that the present form factor can be the basis for further iterations. Future studies can implement the proposed features to address other clinical and ergonomic needs.

Adenoid cystic carcinoma is a malignant tumor of the head and neck, this article reports a case of a large adenoid cystic carcinoma of the skull base, with the lesion involving the sphenoid sinus, sphenoid bone wings, pterygopalatine fossa, nfratemporal fossa, hard palate, and other structures. The treatment plan consisted of surgical excision, primary reconstrction of the surgical defect,and postoperative radiotherapy, resulting in a favorable prognosis for the patient.
Humans ; Carcinoma, Adenoid Cystic/surgery* ; Maxillary Sinus/surgery* ; Maxillary Sinus Neoplasms/surgery* ; Palate, Hard/surgery* ; Skull Base Neoplasms/surgery* ; Surgical Flaps

Objective:To analyze the application efficacy of employing high-density porous polyethylene （Su-por） in combination with temporoparietal fascial flaps via a minimally invasive scalp incision in auricular reconstruction. Methods:This study carried out a retrospective analysis of 50 patients （50 ears in total） who underwentprimary auricular reconstruction with a Su-por scaffold in our hospital from June 2022 to January 2024. All patients underwent primary auricular reconstruction using a minimally invasive scalp incision with high-density porous polyethylene （Su-por） and temporoparietal fascial flaps. The postoperative treatment effects and complications were statistically analyzed. Results:The reconstructed ears of all patients survived. After 6 months of follow-up, the scar hyperplasia of the scalp minimally invasive incision was not obvious in any patient, and no significant hair loss was observed. The reconstructed auricle of 48 patients had a realistic shape and strong three-dimensional sense. With the extension of follow-up time, the three-dimensional structure of the auricle became clearer, and patient satisfaction increased. Among the remaining two patients, one case of flap necrosis survived after skin grafting and dressing changes. One patient had scar hyperplasia at the incision of the reconstructed ear due to a scar-prone constitution, and the shape of the auricle was not ideal, but the scar hyperplasia at the scalp incision was not obvious. Conclusion:One-stage ear reconstruction with high-density porous polyethylene （Su-por） combined with superficial temporal fascia flap through a minimally invasive scalp incision can better show the fine structure of the reconstructed ear. The minimally invasive scalp incision can effectively reduce the occurrence of scar hyperplasia and postoperative alopecia at the scalp incision.
Humans ; Plastic Surgery Procedures/methods* ; Retrospective Studies ; Surgical Flaps ; Tissue Scaffolds ; Polyethylene ; Ear Auricle/surgery* ; Male ; Scalp/surgery* ; Female ; Skin Transplantation ; Fascia/transplantation* ; Porosity ; Adult ; Middle Aged

Objective:To investigate the application value of nasolabial flaps in addressing tissue defects after resection of benign and malignant nasal vestibular lesions. Methods:The clinical data of patients with benign and malignant nasal vestibular lesions were analyzed retrospectively. There were 4 cases of squamous cell carcinoma, 2 cases of black hairy nevus and 1 case of chronic proliferative inflammatory lesions, all of which were repaired by adjacent nasolabial flap. Results:After 6 months of follow-up, none of the patients developed nasal vestibular contracture or nostril stenosis, and postoperative nasal ventilation function was good. Conclusion:The preoperative design of individual nasolabial flaps is very important for maintaining maxillofacial aesthetics, protectingthe nasolabial framework, and preserving postoperative nasal ventilation function.
Humans ; Retrospective Studies ; Middle Aged ; Nose Neoplasms/surgery* ; Surgical Flaps ; Male ; Female ; Adult ; Nose/surgery* ; Plastic Surgery Procedures/methods* ; Carcinoma, Squamous Cell/surgery* ; Aged ; Skin Transplantation

Objective:This study aims to explore the clinical effectiveness of a novel treatment method for refractory laryngeal contact granuloma, involving CO2 laser excision with local pedicled mucosal flap transfer combined with type A botulinum toxin injection. Methods:A retrospective analysis was conducted on 18 patients with refractory laryngeal contact granuloma who visited Department of Otolaryngology Head and Neck Surgery, Nanjing Tongren Hospital, School of Medicine, Southeast University from January 2021 to June 2023. These patients underwent CO2 laser excision of the granuloma with local pedicled mucosal flap transfer combined with type A botulinum toxin injection. During follow-up, electronic laryngoscopy were performed at 1, 3, 6, and 12 months postoperatively, and local laryngeal mucosa, voice quality, and pharyngeal discomfort symptoms were evaluated. Results:Postoperative electronic laryngoscopy revealed the disappearance of granulomas in all 18 patients. Symptoms such as hoarseness, foreign body sensation in the throat, and cough were significantly improved. No complications were observed systemically or locally. No recurrence was observed during one-year follow-up. Conclusion:CO2 laser excision of granuloma with local pedicled mucosal flap transfer combined with type A botulinum toxin injection could eliminate the lesion, restore the integrity of the vocal fold lining, preserve the perichondrium, and provide a time window for mucosal flap recovery. This approach adheres to the principle of preserving normal mucosa, achieves a high cure rate, and is therefore worthy of widespread promotion and application in clinical practice.
Humans ; Retrospective Studies ; Surgical Flaps ; Botulinum Toxins, Type A/administration & dosage* ; Male ; Female ; Granuloma/therapy* ; Adult ; Middle Aged ; Granuloma, Laryngeal/therapy* ; Laryngeal Diseases/therapy* ; Lasers, Gas/therapeutic use* ; Laryngoscopy ; Laser Therapy ; Treatment Outcome

Objective:To compare the clinical outcomes of reconstruction of oral and maxillofacial soft tissue defects using superficial circumflex iliac artery perforator flap （SCIA PF） and radial forearm free flap （RFF）. Methods:A retrospective analysis was conducted on 90 patients with head, neck, and maxillofacial tumors who were treated in our department from June 2019 to January 2024. Patients were divided into two groups based on the surgical method used: the SCIA group（n=45）, who underwent reconstruction with SCIA PF, and the RFF group（n=45）, who received RFF reconstruction. Six months postoperatively, clinical efficacy was evaluated by comparing flap swelling, flap survival rate, and patient satisfaction. Oral function was assessed using standardized scoring systems before surgery, at 1 week, 3 months, and 6 months post-surgery. Hemorheological parameters, including high-shear viscosity（shear rate 200/s）, low-shear viscosity（shear rate 30/s）, plasma viscosity, erythrocyte aggregation index, and erythrocyte sedimentation rate（ESR）, were also measured at each time point. Results:Compared with the RFF group, the SCIA group showed significantly larger flap size, longer flap harvesting and reconstruction times, earlier nasogastric tube removal and oral intake initiation, higher scores in all aspects of oral function, reduced flap edema and faster resolution, higher flap survival rates, and greater overall satisfaction （all P<0.05）. During the follow-up period （preoperative, 1 week, 3 months, and 6 months post-surgery）, hemorheological indices including high-and low-shear viscosity, plasma viscosity, erythrocyte aggregation index, and ESR progressively decreased in the SCIA group （P<0.05）. In the RFF group, these parameters improved significantly by 6 months postoperatively compared with preoperatively and 1-week postoperatively, with a notable decrease in erythrocyte aggregation index at 6 months （P<0.05）. Conclusion:Compared with RFF, SCIA PF provides larger flaps, better functional recovery, higher patient satisfaction, improved flap survival, fewer complications, and more favorable hemorheological profiles following reconstructive surgery for oral and maxillofacial defects.
Humans ; Perforator Flap/blood supply* ; Plastic Surgery Procedures/methods* ; Retrospective Studies ; Free Tissue Flaps ; Iliac Artery/transplantation* ; Forearm/surgery* ; Male ; Female ; Soft Tissue Injuries/surgery* ; Head and Neck Neoplasms/surgery* ; Middle Aged ; Treatment Outcome ; Adult

Objective:To assess the efficacy of "three-step" strategy for preparing autologous pedicled nasal mucosal flaps in repairing cerebrospinal fluid（CSF） leaks following transsphenoidal pituitary adenoma surgery. Methods:A retrospective study was conducted on the clinical data of 25 patients who developed CSF leaks after transsphenoidal pituitary adenoma surgery at the First Affiliated Hospital of Kunming Medical University between July 2012 and June 2022. Surgical repair was selected step by step using nasal septal mucosal flap with either the posterior septal artery or septal branch of the sphenopalatine artery as the pedicle, or a pedicled middle turbinate mucosal flap. All patients underwent ≥2-year endoscopic follow-up to assess flap viability and CSF leak recurrence. Results:The median postoperative hospital stay was 4 days. Five patients developed intracranial infections postoperatively. The follow-up period ranged from 2 to 12 years. Nasal endoscopic examinations showed good mucosal flap growth, with no recurrence of CSF leakage in any of the patients. Conclusion:High-flow cerebrospinal fluid（CSF） leaks following pituitary tumor surgery pose significant challenges for clinical repair. Based on intraoperative nasal septal mucosal preservation and the condition of sellar base CSF leakage, the "three-step" strategy for preparing autologous pedicled nasal mucosal flaps-utilizing posterior septal artery, ethmoidal artery-based, or pedicled middle turbinate mucosal flaps sequentially-is a safe and effective repair method.
Humans ; Retrospective Studies ; Pituitary Neoplasms/surgery* ; Surgical Flaps ; Nasal Mucosa/surgery* ; Cerebrospinal Fluid Leak/surgery* ; Adenoma/surgery* ; Postoperative Complications/surgery* ; Male ; Female ; Middle Aged ; Adult ; Aged

Objective:To observe the effects of different repair methods in the defects after Mohs surgical excision of malignant nasal tumors. Methods:Twenty-two cases of external nasal malignant tumor surgery from January 2021 to May 2024 were selected as the research. The tumors were resected using Mohs surgical technique, and the defects were repaired using forehead axial flap, bipedicle flap, nasolabial flap, free full-thickness skin graft from the groin, forehead axial flap, facial kite flap, and composite flap of earlobe cartilage and perichond. The postoperative flap survival, external nasal morphology, and tumor recurrence were observed. Results:Among the 22 cases, there were 1 case of Kaposis sarcoma（KS）, 2 cases of squ cell carcinoma, and 19 cases of basal cell carcinoma. Tumors were located at the nasal root in 3 cases, the nasal dorsum in5 cases, the nasal tip in 2 cases, the ala in 8 cases, both the ala and the nasal dorsum in 2 cases, nasal columella, the nasal tip, and the ala in 1 case, the nasal tip, the nasal dorsum, the ala, and paranasal area in 1 case. The size of the defects ranged from 1.2 cm×1.4 cm to 3.7 cm×4.8 cm. Three cases were repaired with forehead axial flaps, four cases with bilobed flaps, thirteen cases with nasolabial groove flaps, one case with free full-thickness skin grafts from the inguinal region, and one case with a combination of forehead axial flaps and facial kite flaps plus a composite of earlobe cartilage and perichondrium. All flaps survived well after surgery. Patients were followed up for 6 months to 3 years after surgery, during which no tumor recurrence was observed, and most patients were satisfied with appearance of their nose. Conclusion:Mohs surgery is used to excise the malignant tumor of the external nose, and satisfactory surgical results can be obtained by using different repair methods based the location and size of the postoperative defect.
Humans ; Mohs Surgery/methods* ; Nose Neoplasms/surgery* ; Surgical Flaps ; Skin Transplantation ; Male ; Carcinoma, Basal Cell/surgery* ; Skin Neoplasms/surgery* ; Female ; Middle Aged ; Plastic Surgery Procedures/methods* ; Nose/surgery* ; Aged ; Adult ; Carcinoma, Squamous Cell/surgery*

BACKGROUND AND OBJECTIVES

Mouth retractors are essential in ensuring efficient yet safe exposure of the oral cavity and oropharynx. However, when applied improperly or haphazardly, retractors can cause tissue injuries and compromise patient safety. In addition, there are gaps in the usability of existing designs. This study aimed to identify the issues encountered by otorhinolaryngology surgeons in the use of commercially available mouth retractors, design and fabricate an improved retractor, and explore the use of additive manufacturing (popularly known as 3D printing) for retractor prototyping.

The study used the United States Food and Drug Administration (US FDA) Design Control as its framework. End-user requirements from otorhinolaryngologists were collected through key informant interviews. Results were organized into a Design Input template which was used to guide the design and development process. Prototype designs were iteratively created using computer-aided design software and 3D printing. Once design specifications were satisfied, a beta prototype was fabricated and given to another cohort of otorhinolaryngologists. The participants assessed the usability of the beta prototype. System Usability Scale (SUS) was used to quantify participant's feedback.

Five designs were created in the course of the study. The final prototype was fabricated using a Stereolithography (SLA) 3D printer. Several features were developed to address user requirements. The primary modification was to make the retractor modular to facilitate easier and shorter mounting and assembly. Gingival injury was addressed with the replacement of the maxillary alveolus hook with support bars. Five participants evaluated the beta prototype which received a mean SUS score of 75, well above the 50th percentile threshold.

This study demonstrates the applicability of the US FDA Design Control Process in the local setting to improve the mouth retractor design. Clinical and ergonomic issues were identified and design solutions were proposed and some have been implemented in a low-fidelity prototype. Results of the small-scale usability test suggest that the present form factor can be the basis for further iterations. Future studies can implement the proposed features to address other clinical and ergonomic needs.

Prosthesis loosening is the leading cause of postoperative revision in unicompartmental knee arthroplasty (UKA). The deviation of medial and lateral translational installation of the prosthesis during surgery is a common clinical phenomenon and an important factor in increasing the risk of prosthesis loosening. This study established a UKA finite element model and a bone-prosthesis fixation interface micromotion prediction model. The predicted medial contact force and joint motion of the knee joint from a patient-specific lower extremity musculoskeletal multibody dynamics model of UKA were used as boundary conditions. The effects of 9 femoral component medial and lateral translational installation deviations on the Von Mises stress of the proximal tibia, the contact stress, and the micro-motion of the bone prosthesis fixation interface were quantitatively studied. It was found that compared with the neutral position (a/A of 0.492), the lateral translational deviation of the femoral component significantly increased the tibial Von Mises stress and the bone-prosthesis fixation interface contact stress. The maximum Von Mises stress and the maximum contact stress of the fixation interface increased by 14.08% and 143.15%, respectively, when a/A was 0.361. The medial translational deviation of the femoral component significantly increased the bone-prosthesis fixation interface micro-motion. The maximum value of micromotion under the conditions of femoral neutral and medial translation deviation was in the range of 20-50 μm, which is suitable for osseointegration. Therefore, based on considerations such as the micromotion range suitable for osseointegration reported in the literature, the risk of reducing prosthesis loosening, and factors that may induce pain, it is recommended that clinicians control the mounting position of the femoral component during surgery within the safe range of 0-4 mm medial translation deviation.
Humans ; Arthroplasty, Replacement, Knee/methods* ; Finite Element Analysis ; Biomechanical Phenomena ; Knee Prosthesis ; Tibia/surgery* ; Femur/surgery* ; Stress, Mechanical ; Prosthesis Failure ; Knee Joint/surgery* ; Prosthesis Design