Nonsurgical management of a large necrotic nasal tip wound using a viable cryopreserved placental membrane

The Use of Urinary Bladder Matrix for Reconstructing Avulsed Traumatic Soft Tissue Injuries to the Maxillofacial Region

INTRODUCTION

The purpose of the study was to provide an overview of our initial experience utilizing urinary bladder matrix (UBM) for reconstructing avulsed injuries resulting from trauma.

MATERIALS AND METHODS

This retrospective case series evaluated patients presented with avulsed soft tissue injuries to the head and neck who underwent reconstruction with UBM. Patients were treated by Oral and Maxillofacial Surgery Service in Louisiana State University Health Sciences Center (Baton Rouge, LA). Descriptive variables were collected. Descriptive statistics were calculated.

RESULTS

Eight patients (mean age 55.8 y) met our inclusion criteria. Wounds were located in the scalp (n=2, 25%), mandible (n=2, 25%), upper eyelid (n=1, 12.5%), cheek (n=1, 12.5%), nose (n=1, 12.5%), or neck (n=1, 12.5%). The depth of the wound extended from the skin to the subcutaneous tissue (n=1, 12.5%), muscle (n=2, 25%), bone (n=3, 37.5%), and/or cartilage (n=1, 12.5%). The mean wound diameter was 47.9 cm 2 (range 17-85 cm 2 ). Wounds were classified as acute (n=6, 75%) or chronic wounds (n=2, 25%). At 6 months, all patients had achieved complete healing with no need for additional surgical procedures (n=8, 100%) with a mean healing time of 36.5 days (range 14-90 d).

CONCLUSION

Urinary bladder matrix minimize donor-side morbidity, eliminates contraction, and offers a wide range of product sizes to cover a wide range of maxillofacial soft tissue defects in a single-stage manner.

Single-stage acellular dermal matrix reconstruction of defects in the nose and ears with exposed cartilage: a prospective case series

BACKGROUND

The treatment of soft tissue defects with exposed cartilage after tumor excision is challenging. Local flap reconstruction causes occasional scarring, especially in non-Caucasian populations. Scar treatment requires secondary procedures for aesthetic modifications. Two-step reconstruction with an acellular dermal matrix addresses this issue and yields highly acceptable aesthetic resultsWe aimed to investigate the efficacy of an artificial dermal matrix cover using one-step reconstruction for defects with cartilage exposure.

METHODS

From July 2018 to September 2020, seven patients were enrolled and underwent a single-stage operation using acellular dermal matrices. Patients were followed up for at least 6 months and the size of the wound, days to heal, patient satisfaction, and scar scale scores were recorded.

RESULTS

Patients were followed up for an average of 25.7 months. The average time to heal was 23.4 days postoperatively. No hyperpigmentation, tumor recurrence, or retraction was noted. High acceptance and satisfaction with the outcome were observed in all patients.

CONCLUSIONS

Single-stage reconstruction yielded high acceptance of aesthetic results similar to that in two-stage reconstruction. Less time and cost make this an effective and efficient treatment for soft tissue defects compared with traditional techniques.

Shape Prediction of Nasal Bones by Digital 2D-Photogrammetry of the Nose Based on Convolution and Back-Propagation Neural Network

In rhinoplasty, it is necessary to consider the correlation between the anthropometric indicators of the nasal bone, so that it prevents surgical complications and enhances the patient's satisfaction. The penetrating form of high-energy electromagnetic radiation is highly impacted on human health, which has often raised concerns of alternative method for facial analysis. The critical stage to assess nasal morphology is the nasal analysis on its anthropology that is highly reliant on the understanding of the structural features of the nasal radix. For example, the shape and size of nasal bone features, skin thickness, and also body factors aggregated from different facial anthropology values. In medical diagnosis, however, the morphology of the nasal bone is determined manually and significantly relies on the clinician's expertise. Furthermore, the evaluation anthropological keypoint of the nasal bone is nonrepeatable and laborious, also finding widely differ and intralaboratory variability in the results because of facial soft tissue and equipment defects. In order to overcome these problems, we propose specialized convolutional neural network (CNN) architecture to accurately predict nasal measurement based on digital 2D photogrammetry. To boost performance and efficacy, it is deliberately constructed with many layers and different filter sizes, with less filters and optimizing parameters. Through its result, the back-propagation neural network (BPNN) indicated the correlation between differences in human body factors mentioned are height, weight known as body mass index (BMI), age, gender, and the nasal bone dimension of the participant. With full of parameters could the nasal morphology be diagnostic continuously. The model's performance is evaluated on various newest architecture models such as DenseNet, ConvNet, Inception, VGG, and MobileNet. Experiments were directly conducted on different facials. The results show the proposed architecture worked well in terms of nasal properties achieved which utilize four statistical criteria named mean average precision (mAP), mean absolute error (MAE), R-square (R²), and T-test analyzed. Data has also shown that the nasal shape of Southeast Asians, especially Vietnamese, could be divided into different types in two perspective views. From cadavers for bony datasets, nasal bones can be classified into 2 morphological types in the lateral view which “V” shape was presented by 78.8% and the remains were “S” shape evaluated based on Lazovic (2015). With 2 angular dimension averages are 136.41 ± 7.99 and 104.25 ± 5.95 represented by the nasofrontal angle (g-n-prn) and the nasomental angle (n-prn-sn), respectively. For frontal view, classified by Hwang, Tae-Sun, et al. (2005), nasal morphology of Vietnamese participants could be divided into three types: type A was present in 57.6% and type B was present in 30.3% of the noses. In particular, types C, D, and E were not a common form of Vietnamese which includes the remaining number of participants. In conclusion, the proposed model performed the potential hybrid of CNN and BPNN with its application to give expected accuracy in terms of keypoint localization and nasal morphology regression. Nasal analysis can replace MRI imaging diagnostics that are reflected by the risk to human body.

Structural and Functional Equivalency Between Lyopreserved and Cryopreserved Chorions with Viable Cells

Objective: Clinical studies have demonstrated that the use of cryopreserved amnion or trophoblast (TR)-free chorion, containing viable cells, in the treatment of chronic wounds results in high rate of wound closure. Recently, a new lyopreservation method has been developed for preservation of amnion that also retains the endogenous viable cells. The objective of this study was to use this method for lyopreservation of TR-free chorionic membrane (viable lyopreserved chorionic membrane [VLCM]) and compare it with the viable cryopreserved chorionic membrane (VCCM). A second objective was to investigate the immunogenicity of chorion, an important question that has not been fully addressed.

Approach: Chorion immunogenicity was tested in vitro in a mixed lymphocyte reaction and lipopolysaccharide (LPS) challenge assay, and in vivo in a mouse subcutaneous pocket implantation model. VLCM tissue structure was assessed histologically, growth factor content by multiplex assay, and cell viability by LIVE/DEAD cell fluorescent staining. Inhibition of tumor necrosis factor α secretion by LPS-activated THP-1 cells and endothelial cell tubule formation assays were performed to evaluate the anti-inflammatory and proangiogenic properties, respectively. An in vivo rabbit abdominal adhesion model was used to evaluate the antifibrotic properties.

Results: Chorionic membrane without trophoblast (CM) was shown to be nonimmunogenic. Tissue architecture, growth factors, and cell viability of fresh CM were maintained in VLCM and VCCM. In vitro studies showed that anti-inflammatory and angiogenic properties were retained in VLCM. Furthermore, VLCM prevents formation of postsurgical adhesions in a rabbit abdominal surgical adhesion model.

Innovation: Characterization of structural and functional properties of VLCM is reported for the first time.

Conclusion: Similar to VCCM, VLCM retains native components of fresh CM, including collagen-rich extracellular matrix, growth factors, and viable cells. In vitro and in vivo models demonstrate that VLCM is anti-inflammatory, proangiogenic and antifibrotic. Results of this study support the structural and functional equivalency between VLCM and VCCM.