Deep learning-based clinical decision support system for gastric neoplasms in real-time endoscopy: development and validation study.

BACKGROUND : Deep learning models have previously been established to predict the histopathology and invasion depth of gastric lesions using endoscopic images. This study aimed to establish and validate a deep learning-based clinical decision support system (CDSS) for the automated detection and classification (diagnosis and invasion depth prediction) of gastric neoplasms in real-time endoscopy. METHODS : The same 5017 endoscopic images that were employed to establish previous models were used for the training data. The primary outcomes were: (i) the lesion detection rate for the detection model, and (ii) the lesion classification accuracy for the classification model. For performance validation of the lesion detection model, 2524 real-time procedures were tested in a randomized pilot study. Consecutive patients were allocated either to CDSS-assisted or conventional screening endoscopy. The lesion detection rate was compared between the groups. For performance validation of the lesion classification model, a prospective multicenter external test was conducted using 3976 novel images from five institutions. RESULTS : The lesion detection rate was 95.6 % (internal test). On performance validation, CDSS-assisted endoscopy showed a higher lesion detection rate than conventional screening endoscopy, although statistically not significant (2.0 % vs. 1.3 %; P = 0.21) (randomized study). The lesion classification rate was 89.7 % in the four-class classification (advanced gastric cancer, early gastric cancer, dysplasia, and non-neoplastic) and 89.2 % in the invasion depth prediction (mucosa confined or submucosa invaded; internal test). On performance validation, the CDSS reached 81.5 % accuracy in the four-class classification and 86.4 % accuracy in the binary classification (prospective multicenter external test). CONCLUSIONS : The CDSS demonstrated its potential for real-life clinical application and high performance in terms of lesion detection and classification of detected lesions in the stomach.

Deep Learning-Based Diagnostic System for Velopharyngeal Insufficiency Based on Videofluoroscopy in Patients With Repaired Cleft Palates.

Velopharyngeal insufficiency (VPI), which is the incomplete closure of the velopharyngeal valve during speech, is a typical poor outcome that should be evaluated after cleft palate repair. The interpretation of VPI considering both imaging analysis and perceptual evaluation is essential for further management. The authors retrospectively reviewed patients with repaired cleft palates who underwent assessment for velopharyngeal function, including both videofluoroscopic imaging and perceptual speech evaluation. The final diagnosis of VPI was made by plastic surgeons based on both assessment modalities. Deep learning techniques were applied for the diagnosis of VPI and compared with the human experts' diagnostic results of videofluoroscopic imaging. In addition, the results of the deep learning techniques were compared with a speech pathologist's diagnosis of perceptual evaluation to assess consistency with clinical symptoms. A total of 714 cases from January 2010 to June 2019 were reviewed. Six deep learning algorithms (VGGNet, ResNet, Xception, ResNext, DenseNet, and SENet) were trained using the obtained dataset. The area under the receiver operating characteristic curve of the algorithms ranged between 0.8758 and 0.9468 in the hold-out method and between 0.7992 and 0.8574 in the 5-fold cross-validation. Our findings demonstrated the deep learning algorithms performed comparable to experienced plastic surgeons in the diagnosis of VPI based on videofluoroscopic velopharyngeal imaging.

Adipose-derived stem cells delay muscle atrophy after peripheral nerve injury in the rodent model.

INTRODUCTION: Injuries to peripheral nerves cause distal muscle atrophy. The effects of adipose-derived stem cell (ASC) injections into a muscle after injury were examined. METHODS: A 1.5 cm defect in the rat sciatic nerve was created, resulting in gastrocnemius muscle atrophy. The nerve defect was repaired with autograft; DiR-labeled ASCs were injected into the gastrocnemius immediately postoperatively. Quantitation of gross musculature and muscle fiber area, cell survival, fibrosis, lipid deposition, inflammation, and reconstructive responses were investigated. RESULTS: ASCs were identified in the muscle at 6 weeks, where injections showed increased muscle mass percentage retained, larger average fiber area, and less overall lipid content accumulated throughout the musculature. Muscles having received ASCs showed increased presence of interlukin-10 and Ki67, and decreased inducible nitric oxide synthase (iNOS). DISCUSSION: This investigation is suggestive that an ASC injection into denervated muscle post-operatively is able to delay the onset of atrophy. Muscle Nerve 59:603-603, 2019.

Delivery of adipose-derived stem cells in poloxamer hydrogel improves peripheral nerve regeneration.

INTRODUCTION: Peripheral nerve damage is associated with high long-term morbidity. Because of beneficial secretome, immunomodulatory effects, and ease of clinical translation, transplantation with adipose-derived stem cells (ASC) represents a promising therapeutic modality. METHODS: Effect of ASC delivery in poloxamer hydrogel was assessed in a rat sciatic nerve model of critical-sized (1.5 cm) peripheral nerve injury. Nerve/muscle unit regeneration was assessed via immunostaining explanted nerve, quantitative polymerase chain reaction (qPCR), and histological analysis of reinnervating gastrocnemius muscle. RESULTS: On the basis of viability data, 10% poloxamer hydrogel was selected for in vivo study. Six weeks after transection and repair, the group treated with poloxamer delivered ASCs demonstrated longest axonal regrowth. The qPCR results indicated that the inclusion of ASCs appeared to result in expression of factors that aid in reinnervating muscle tissue. DISCUSSION: Delivery of ASCs in poloxamer addresses multiple facets of the complexity of nerve/muscle unit regeneration, representing a promising avenue for further study. Muscle Nerve 58: 251-260, 2018.

Do IL-3/GM-CSF effect on the myofibroblastic differentiation of human adipose derived stromal cells?

BACKGROUND: Capsular contracture is an incurable complication after silicone-based implant surgery. Myofibroblast is the predominant cell in the contracted capsule. We hypothesized that human adipose derive stromal cells (hASCs) together with fibroblast may show a similar phenotypic characteristics of myofibroblast after the treatment of inflammatory cytokines in vitro. MATERIALS AND METHODS: Interleukin 3 (IL-3) and granulocyte macrophage colony stimulating factor (GM-CSF) were treated in the culture of hASCs and HDFs. Lyn peptide inhibitor was applied as an inhibitor. The changes of cell surface markers (CD105, CD73, CD34, CD45, CD31, CD325 and CD146) were assessed. The expression of various cytokines related to wound contraction were tested such as TGF-ß, α-SMA, HGF, FGF, ENT-1, and TSP-1. Myo-D, α-SMA, and glial fibrillary acidic protein (GFAP) were evaluated by blotting and immunocytochemical staining. The collagen-gel contraction assay was performed for the functional contraction of myofibroblastic phenotype. RESULTS: The expression of α-SMA, Myo-D and GFAP after the treatment of IL-3/GM-CSF showed similar results in hASCs and HDFs. Enhanced expression of TGF- ß was observed in HDFs and the increase of ENT-1 and TSP-1 was significant in hASCs. Collagen-gel with HDFs contracted significantly within 24h after the treatment of IL-3/GM-CSF, and the contraction was inhibited by Lyn peptide inhibitor. But in hASCs, the gel-contraction was not significant. CONCLUSION: IL-3/ GM-CSF effected on the myofibroblastic differentiation of hASCs as well as it did on HDFs. But hASCs did not show the phenotypic gel-contraction within 24h.

Optimal Viscosity and Particle Shape of Hyaluronic Acid Filler as a Scaffold for Human Fibroblasts.

The authors previously reported that cultured human fibroblasts suspended in a hyaluronic acid filler can produce human dermal matrices with extended in vivo stability in animal and clinical studies. The present study was undertaken to determine the optimal viscosity and particle shape of hyaluronic acid filler as a scaffold for cultured human dermal fibroblasts to enhance the maximal viability of injected cells. The fibroblasts were suspended in either 1 of 3 hyaluronic acid viscosities at 2 different particle shapes. The viscosities used in this study were low (600,000-800,000 centipoises), moderate (2,000,000-4,000,000 centipoises), and high (8,000,000-12,000,000 centipoises). The particle shape was evaluated by testing round and irregular shapes. The fibroblast mixed bioimplants were injected into the back of individual athymic nude mice. The levels of type I collagen were measured using fluorescent-activated cell sorting (FACS) and immunohistochemical staining at 16 weeks after the injections. Results of FACS demonstrated that the mean cell ratio with human collagens in the moderate viscosity group was greater than those of control, low, and high viscosity groups. An immunohistochemical study showed similar results. The moderate viscosity group demonstrated the highest positive staining of human collagens. However, there were no significant differences between groups of irregular and round shape particles. A hyaluronic acid bioimplant with moderate viscosity is superior to that with low or high viscosity in the viability for human fibroblasts. However, the particle shape does not influence the viability of the fibroblasts.

Temporary blindness after an anterior chamber cosmetic filler injection.

UNLABELLED: Blindness is a rare but devastating complication of cosmetic filler injection. A primary cause of blindness following hyaluronic acid filler injection is retrograde intravascular embolization into the small ocular arteries. We here report a case of temporary blindness associated with the injection of hyaluronic acid filler into the anterior chamber of eye. This is the first report of temporary blindness after cosmetic filler injection into the anterior chamber, and the first described case that recovered completely after the filler was removed. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Effects of platelet-rich plasma, adipose-derived stem cells, and stromal vascular fraction on the survival of human transplanted adipose tissue.

Traditional adipose tissue transplantation has unpredictable viability and poor absorption rates. Recent studies have reported that treatment with platelet-rich plasma (PRP), adipose-derived stem cells (ASCs), and stromal vascular fraction (SVF) are related to increased survival of grafted adipose tissue. This study was the first simultaneous comparison of graft survival in combination with PRP, ASCs, and SVF. Adipose tissues were mixed with each other, injected subcutaneously into the back of nude mice, and evaluated at 4, 8, and 12 weeks. Human adipocytes were grossly maintained in the ASCs and SVF mixtures. Survival of the adipose tissues with PRP was observed at 4 weeks and with SVF at 8 and 12 weeks. At 12 weeks, volume reduction in the ASCs and SVF mixtures were 36.9% and 32.1%, respectively, which were significantly different from that of the control group without adjuvant treatment, 51.0%. Neovascular structures were rarely observed in any of the groups. Our results suggest that the technique of adding ASCs or SVF to transplanted adipose tissue might be more effective than the conventional grafting method. An autologous adipose tissue graft in combination with ASCs or SVF may potentially contribute to stabilization of engraftment.

Long-gap peripheral nerve repair through sustained release of a neurotrophic factor in nonhuman primates.

Severe injuries to peripheral nerves are challenging to repair. Standard-of-care treatment for nerve gaps >2 to 3 centimeters is autografting; however, autografting can result in neuroma formation, loss of sensory function at the donor site, and increased operative time. To address the need for a synthetic nerve conduit to treat large nerve gaps, we investigated a biodegradable poly(caprolactone) (PCL) conduit with embedded double-walled polymeric microspheres encapsulating glial cell line-derived neurotrophic factor (GDNF) capable of providing a sustained release of GDNF for >50 days in a 5-centimeter nerve defect in a rhesus macaque model. The GDNF-eluting conduit (PCL/GDNF) was compared to a median nerve autograft and a PCL conduit containing empty microspheres (PCL/Empty). Functional testing demonstrated similar functional recovery between the PCL/GDNF-treated group (75.64 ± 10.28%) and the autograft-treated group (77.49 ± 19.28%); both groups were statistically improved compared to PCL/Empty-treated group (44.95 ± 26.94%). Nerve conduction velocity 1 year after surgery was increased in the PCL/GDNF-treated macaques (31.41 ± 15.34 meters/second) compared to autograft (25.45 ± 3.96 meters/second) and PCL/Empty (12.60 ± 3.89 meters/second) treatment. Histological analyses included assessment of Schwann cell presence, myelination of axons, nerve fiber density, and g-ratio. PCL/GDNF group exhibited a statistically greater average area occupied by individual Schwann cells at the distal nerve (11.60 ± 33.01 µm2) compared to autograft (4.62 ± 3.99 µm2) and PCL/Empty (4.52 ± 5.16 µm2) treatment groups. This study demonstrates the efficacious bridging of a long peripheral nerve gap in a nonhuman primate model using an acellular, biodegradable nerve conduit.

Intraoperative venous congestion in free transverse rectus abdominis musculocutaneous and deep inferior epigastric artery perforator flaps during breast reconstruction: A systematic review.

BACKGROUND: Even with patent deep inferior epigastric vein anastomoses, venous congestion can occur during free transverse rectus abdominis musculocutaneous (TRAM) or deep inferior epigastric artery perforator (DIEP) flap surgery and lead to flap compromise if not recognized and managed. OBJECTIVES: To identify the incidence of intraoperative venous congestion and describe the best available prevention and treatment methods. METHODS: Systematic electronic searches of the PubMed database including Medline were performed to identify studies published until 2014. The following keywords were used: "DIEP" or "free TRAM" and "venous insufficiency" or "venous congestion". Supplemental searches were conducted to identify referenced studies. Statistical analysis using the χ(2) test was performed. RESULTS: Nine studies representing 4747 free abdominal flaps cases were included and demonstrated an overall incidence of intraoperative venous congestion of 2.8%. The incidence in DIEP flaps (3.3%) was significantly higher than that in the free TRAM flaps (1.0%). All nine articles reported using the superficial inferior epigastric vein to treat venous insufficiency. CONCLUSION: The risk for developing intraoperative venous congestion following free abdominal flap breast reconstruction is influenced by inadequate perforator selection and persistent dominance in the superficial venous system. The solution is establishing another venous draining route using the superficial inferior epigastric vein.

HISTORIQUE: Malgré des anastomoses de la veine épigastrique inférieure profonde perméable, une congestion veineuse peut survenir pendant une chirurgie par lambeau libre musculocutané du grand droit transverse (MGDT) ou par lambeau perforant de l'artère épigastrique inférieure profonde (AEIP) et compromettre le lambeau si elle n'est pas décelée et prise en charge. OBJECTIFS: Déterminer l'incidence de congestion veineuse peropératoire et décrire les meilleures méthodes préventives et thérapeutiques en place. MÉTHODOLOGIE: Les chercheurs ont effectué des recherches virtuelles systématiques dans la base de données PubMed, y compris dans Medline, pour extraire les études publiées jusqu'en 2014. Ils ont utilisé les mots-clés suivants : DIEP ou free TRAM et venous insufficiency ou venous congestion. Ils ont mené d'autres recherches pour extraire les études des références. Ils ont effectué une analyse statistique au moyen du test du chi carré. RÉSULTATS: Neuf études représentant 4 747 cas de lambeaux abdominaux libres ont été incluses, pour démontrer une incidence globale de congestion veineuse peropératoire de 2,8 %. L'incidence de lambeaux AEIP (3,3 %) était considérablement plus élevée que celle de lambeaux libres MGDT (1,0 %). Dans les neuf articles, la veine épigastrique inférieure profonde était utilisée pour traiter l'insuffisance veineuse. CONCLUSION: Le risque de congestion veineuse peropératoire après une reconstruction mammaire par lambeaux abdominaux libres est influencé par une mauvaise sélection du lambeau perforant et une dominance persistante du système veineux superficiel. La solution consiste à établir une autre voie de drainage veineux au moyen de la veine épigastrique inférieure superficielle.