Case Report of Gas Gangrene after Reconstructive Surgery with Anterolateral Thigh Flap for Resection of Oral Cancer.

Necrotizing fasciitis (NF) type I is an acute subcutaneous tissue infection that can promptly disseminate generating crepitus. If not accurately diagnosed and expeditiously treated, it becomes a life-threatening infection. In this report, we present a 65-year-old man who developed a case of NF after a hemiglossectomy resecting a tumor in the dorsal surface of the tongue. A biopsy was performed, and he was pathologically diagnosed with squamous cell carcinoma (T2N1M0). The patient underwent preoperative oral cleaning. Right hemiglossectomy was performed by cervical dissection, pull-through style, with tooth removal on the right mandible and a left anterolateral femoral flap reconstruction. Routine intraoperative lavage was performed with 2000 mL of saline solution. Cefazolin 1gr was administered two times per day postoperatively. Four days after primary surgery, the flap circulation was inadequate; therefore, a computed tomography scan was taken, which indicated gas in the ventral neck area. Tooth extraction was the suspected etiology. Debridement was performed; the abscess was drained and cultured, indicating the presence of Staphylococcus haemolyticus and Escherichia coli. It seems that the abscess was not formed by NF, but rather by leachate reservoir associated with the head and neck tumor. After debridement, re-reconstruction was performed with a deltopectoral flap and pectoralis major myocutaneous flap. When NF is present after a neck dissection, there is a risk of disruption due to the direct invasion and inflammation into the carotid artery. Therefore, it is important to provide adequate oral cleaning care before the surgery and early suspicion of the diagnosis.

Evaluation of the Superficial Collecting Lymph Vessels' Vasa Vasorum in Lymphoedematous Limbs Using Video Capillaroscopy.

OBJECTIVE: The pre-collecting and collecting lymph vessels have smooth muscle cells, and sufficient perfusion is vital to maintain their function. Although the vasa vasorum of the collecting lymph vessels (VVCL) have been histologically investigated, little is known about their physiology. This study aimed to investigate the relationship between morphology and blood flow of the VVCL in lymphoedematous limbs. METHODS: Medical records of lower extremity lymphoedema patients who underwent video capillaroscopy observation during supermicrosurgical lymphaticovenous anastomosis (LVA) surgery were reviewed. The collecting lymph vessels, dissected for LVA, were examined under video capillaroscopy (GOKO Bscan-ZD, GOKO Imaging Devices Co., Japan) with a magnification of 175x and 620x. Blood flow velocity of the VVCL was calculated by measuring the red blood cell movement using software (GOKO-VIP ver. 1.0.0.4, GOKO Imaging Devices Co., Japan). Based on the video capillaroscopy findings, the VVCL were grouped according to their morphology; the VVCL morphology types and blood flow velocity were then compared according to the lymphosclerosis severity grade. RESULTS: Sixty-seven lymph vessels in 20 lower extremity lymphoedema patients were evaluated, including s0 in 19 (28.4%), s1 in 34 (50.7%), s2 in 10 (14.9%), and s3 in four (6.0%) lymph vessels. The VVCLs were grouped into four types: type 1 (n = 4), type 2 (n = 37), type 3 (n = 19), and type 4 (n = 7). Blood flow velocity of the VVCL ranged 0 - 189.3 µm/sec (average 26.40 µm/sec). There were statistically significant differences in VVCL morphology (p < .001) and blood flow velocity (p < .001) according to lymphosclerotic severity. CONCLUSION: Vasa vasorum of the collecting lymph vessels could be grouped into four types with different characteristics. Morphological and physiological changes of the VVCL were related to sclerotic changes of the collecting lymph vessels.

Distal Nerve Transfers in Hand and Forearm for Traumatic Brachial Plexus and Peripheral Nerve Injuries: A Narrative Review.

Background: Various studies published good outcomes in brachial plexus injuries using nerve transfers for shoulder and elbow functions. However, little is known about the outcome of the distal nerve transfers in the forearm and hand. Targeting the nerve distally produces an early return of function in brachial plexus and peripheral nerve injuries (BPPNI). Therefore, researchers have focused on nerve transfers from the motor branches of the ulnar, median, and radial nerve. Similarly, sensory reinnervation is also obtained by potential donor transfers in the forearm and hand. There have been various attempts by surgeons to target the muscle and promote early reinnervation by different nerve transfers. Conclusions: The distal nerve transfers in the forearm and hand are promising when performed early. It effectively restores hand and forearm functions and may be considered a better option than tendon transfer, which has a one-tendon-one function. This narrative review article discusses the different distal nerve transfers for various presentations of BPNNI.

Clinical applications of the chimeric anterolateral thigh (ALT) flap in head and neck reconstruction.

BACKGROUND: Surgical site infection (SSI) is a common complication following head and neck surgery. Dead space at the excision site can increase the risk of infection, abscess formation, and mortality. Herein, we evaluated the performance of the chimeric anterolateral thigh (ALT) flap in addressing these concerns. METHODS: Patients who underwent oncologic head and neck reconstruction between October 2016 and November 2021 were divided in two groups: a normal ALT flap and a chimeric dead space filling (DSF) ALT-vastus lateralis flap group. We evaluated the postoperative outcomes. RESULTS: Twenty-five patients treated with normal ALT flaps (34.7%) and 47 with DSF ALT flap group (65.2%) were included. Only one ALT per case was necessary. Most of the cases involved tongue (31.9%) and lower gingival reconstruction (27.8%). The time to harvest the DSF ALT flap was 134.3 min when compared to the normal ALT flap (116.2 min, p < .001). Vascular occlusion, flap loss, partial necrosis, and fat necrosis were not observed among the different groups. CONCLUSION: The DSF process can be used as a preventive measure for SSI or vessel exposure due to radiation-induced skin damage. This flap allows same-site reconstruction if the primary tumor recurs by using the pedicle of the chimeric flap for reattachment of another free flap.

Characteristics and Limitations of Video-capillaroscopy in Reconstructive Microsurgery for Different Histologic Components of Flaps.

Indocyanine green, ultrasonography, and handheld Doppler can be used to evaluate blood flow at the donor and recipient site during microvascular reconstruction. However, these methods do not provide direct visualization and assessment of real-time blood flow. Video-capillaroscopy has been shown to be useful in clinical practice to assess microcirculation in rheumatologic disorders. In this report we used video-capillaroscopy to assess different tissue components involved in microvascular surgery. Seven patients who underwent head and neck oncologic microvascular reconstruction between November 2021 and February 2022 were included in this study. Video-capillaroscopy (GOKO-BscanZD, GOKO Imaging Devices Co., Ltd., Japan) was used to evaluate the donor-site and recipient-site tissue components. Optimal red blood cell movement was graded with a score of four, while no flow was graded with a score of 0. Seven myocutaneous flaps and seven recipient sites were evaluated. For the donor-site, our analysis demonstrated a significantly higher video-capillaroscopy quality for skin (3.43), adipose tissue (3.7) and perforators (3.7) when compared with muscle (0.429), muscle fascia (0.857), and de-epithelialized skin (1) (P < 0.001). For the recipient-site, a significantly higher video-capillaroscopy quality for skin (2.7), adipose tissue (3.5), and the periosteum (2.1) was noted when compared with muscle (0) (P < 0.001). Video-capillaroscopy efficiency is limited in the muscular component and injured (de-epithelialized) skin surface areas of flaps. Herein, we provide evidence that assessment of flap perfusion with video-capillaroscopy can be reliably achieved in the skin, periosteum, perforators, and adipose tissue. Video-capillaroscopy is expected to be applied for intraoperative real-time blood flow evaluation.

Intraoperative Identification of Perforator Spasm and Decreased Pulsation Using Video-capillaroscopy during Free Flap Harvest.

Temporary or prolonged vascular spasm can be appreciated when perivascular dissection is performed for microvascular reconstruction. Due to a lack of reliable assessment modalities, the resolution of spasm at the periphery of perforators cannot be determined by naked eyes or surgical loupes. To address this conundrum, we aimed to observe the state of perforator vessel spasm after flap elevation using video-capillaroscopy. Between November 2021 and February 2022, seven free flaps were evaluated with video-capillaroscopy to determine the incidence of vasospasm in less than 1 mm-diameter perforators. The type of perforator spasm after flap elevation was divided into six types according to the video-capillaroscopy findings: type A, no spasm/decreased pulsation (S/DP); type B, S/DP with recovery within 5 minutes; type C, S/DP requiring papaverine hydrochloride spraying and hot water treatment (PHS+HWT) resulting in recovery within 5 minutes; type D, S/DP requiring PHS+HWT resulting in recovery within 10 minutes; type E, S/DP requiring PHS+HWT resulting in recovery within 15 minutes; and type F, S/DP with no recovery of pulsation even after PHS+HWT. Twenty-five perforators were evaluated, 3.57 perforators (range, 3-4) per flap. Using our classification for perforator vessel spasms on video-capillaroscopy, observations of five perforating branches were classified as type A, seven as type B, six as type C, five as type D, and two as type E. No type F spasm was observed. With video-capillaroscopy it is possible to confirm if blood flow deterioration occurs even in areas that are difficult to determine macroscopically. Video-capillaroscopy, a noninvasive imaging modality, is a useful alternative for the intraoperative evaluation of perforator flow and spasm.

Combined ALT, Estlander, and Upper Lip Flap for Defects Involving the Oral Commissure.

Lip defects (including the corners of the mouth) are a reconstructive challenge in terms of both aesthetic and functional outcomes. When oral cancer resection results in defects that extend beyond the corners of the mouth to the buccal mucosa and buccal skin, it is difficult to perform reconstructive surgery using only a local flap, and a free flap must be used in combination. In this report, we present a case of reconstructive surgery of the corners of the mouth, buccal mucosa, and buccal skin after tumor resection for buccal mucosal squamous cell carcinoma in a 70-year-old man. The patient presented with a change in an oral mucosal ulcer for a period of 1 year. After biopsy of the ulcerated area, he was pathologically diagnosed with squamous cell carcinoma. After tumor resection, including the corners of the mouth, lips, and cheek skin, and neck dissection, the patient underwent reconstructive surgery using an extended upper lip flap combined with an Estlander flap and a free anterolateral thigh flap. Two months after surgery, the patient was able to consume regular food. At 24 months of follow-up, the patient was able to speak normally without any restrictive symptoms such as fluid leakage from the corner of the mouth. Lip sensation restoration was optimal. This method using the combination of an anterolateral thigh flap and extended Estlander flap is a markedly useful option for reconstructive surgery of defects around the corner of the mouth caused by wide excision of invasive cancer.

Dental Silicone-based Surgical Guides to Harvest the Chimeric Scapular Flap: Preventing Iatrogenic Vascular Injury.

The angular branch of the thoracodorsal artery and the periosteal branches of the circumflex scapular artery can be easily injured while harvesting a chimeric scapular flap. Thus, we reported the use of 3D printed scapular models using CT angiography to prepare inexpensive surgical guides from autoclavable dental silicone impressions for scapular flap harvest. Mandibular and scapular models were prepared using a 3D printer for 11 patients undergoing chimeric scapular flap transfer following mandibular resection. During preoperative simulation surgery, we molded dental silicone accordingly with scapular models to produce surgical cutting guides. Six men (54.5%) and five women (45.5%) were included. The average age of patients was 65.4 years. Fourteen bone units were reconstructed as three patients needed two bone segments (27.3%) whereas eight patients required reconstruction of one bone segment (72.7%). The mean flap harvest time and total surgical time were 52.1 min and 633.8 min, respectively. The mean duration for osteotomies and bone plate fixation was 26.2 min. The difference between the length of the preoperative surgical model (64.92 mm) and the postoperative 3D-CT measurements (64.48 mm) was not statistically significant (0.95 mm, P = 0.397). No injuries were caused to the angular and periosteal vessels. Four patients exhibited donor-site seroma (36.4%). The cost of the dental silicone for surgical guide was only $5 per patient. Dental silicone-based surgical guides help minimize the risk of vascular injury while harvesting chimeric scapular flaps. The osteotomies were performed with precision and in a time-efficient manner.

Real-Time Assessment of Free Flap Capillary Circulation Using Videocapillaroscopy.

BACKGROUND: Free tissue transfer is a common method of reconstruction for various surgical defects. Many clinical assessment methods, including flap color monitoring and capillary refill time measurements, are commonly used to assess the microcirculation of the flap, yet there is no objective tool available that can clear real-time visualization of the flap microcirculation. The purpose of this study was to use a novel videocapillaroscope to evaluate the circulation changes on free flap skin surfaces while purposely clamping pedicle vessels. METHODS: Ten patients who underwent free flap transfer for head and neck cancer from November of 2019 to June of 2020 were included in the study. Videocapillaroscopic observation was performed after flap elevation, and changes in the flap skin capillary circulation with artery-controlled and vein-controlled clamping were recorded. RESULTS: Average total surgery time was 517.91 minutes (SD, 73.3 minutes), average flap elevation time was 102.9 minutes (SD, 18.3 minutes). When the pedicle artery or vein was purposely clamped, the movement of red blood cells in blood vessels stopped; when clamps were removed after 60 seconds, the restoration of red blood cell movements was rapidly observed. When the pedicle artery was clamped, the number of visualizable blood vessels decreased and flap color became relatively white. When the pedicle vein was clamped, the number of visualizable blood vessels increased, and flap color tone had a tendency toward red. CONCLUSION: Novel videocapillaroscopy can be utilized for objective real-time flap monitoring by directly visualizing flap skin capillary microcirculation. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, V.

Dynamic Changes on Video-capillaroscopy and Potential Microsurgical Application: Temperature and Skin Surface Readings.

Video-capillaroscopy is being explored as a potential tool for microsurgical flap monitoring. A detailed examination of the effect of temperature on capillary changes using video-capillaroscopy is yet to be investigated. We analyzed the video-capillaroscopy findings on different skin areas often used for flap harvest at normal body temperatures and at lower temperatures. Skin capillaries at the lateral thigh, anterior forearm, mid-axillary line, abdomen, and fingertips were observed using video-capillaroscopy in 20 healthy Japanese individuals. Further, ImageJ software was used to measure the blood vessel area and blood flow velocity, and comparisons were drawn between normal body temperature and lower body temperature states. All measures of blood vessel area and average blood flow velocity for the different anatomical regions were significantly different before and after cooling (P < 0.001). The mean reduction rate of the vessel area was significantly different among anatomic regions (P < 0.001). Post-hoc analysis revealed a significant difference in the vessel area reduction rate between anatomic areas (P < 0.05); except when comparing the thigh versus finger, the forearm versus abdomen, and the mid-axillary line versus abdomen. The mean blood flow velocity was significantly different among anatomic regions (P < 0.001). Post-hoc analysis revealed a significant difference between the thigh and forearm (P = 0.009), the forearm and fingertip (P = 0.001), and the abdomen and fingertip (P = 0.004). Decreasing the skin temperature resulted in a significant vasoconstriction and reduction in capillary flow velocity. It is imperative to keep the monitored area warm during video-capillaroscopy assessment to avoid false diagnosis of vascular occlusion.

Hypoxia enhances motility and EMT through the Na+/H+ exchanger NHE-1 in MDA-MB-231 breast cancer cells.

Breast cancer metastasis is the leading cause of cancer-related deaths. Hypoxia in the tumor mass is believed to trigger cell migration, which is involved in a crucial process of breast cancer metastasis. However, the molecular mechanisms underlying aggressive behavior under hypoxic conditions have not been fully elucidated. Here, we demonstrate the significant motility of MDA-MB-231 cells cultured under hypoxic conditions compared to that of cells cultured under normoxic conditions. MDA-MB-231 cells under hypoxic conditions showed a significant increase in Na+/H+ exchanger isoform 1 (NHE1) expression level, which was observed to co-locate in lamellipodia formation. Inhibition of NHE1 significantly suppressed the intracellular pH and the expression of mesenchymal markers, thereby blocking the high migration activity in hypoxia. Moreover, treatment with ciglitazone, a potent and selective peroxisome proliferator-activated receptor γ (PPARγ) agonist, modulated hypoxia-enhanced motion in cells via the repression of NHE1. These findings highlight that NHE1 is required for migratory activity through the enhancement of epithelial-mesenchymal transition (EMT) in MDA-MB-231 cells under hypoxic conditions, and we propose new drug repurposing strategies targeting hypoxia based on NHE1 suppression by effective usage of PPARγ agonists.

Use of Dental Impression Silicone to Fabricate Simple Surgical Guides in Mandibular Reconstruction∗.

BACKGROUND: Several recent reports have described the development and use of three-dimensional (3D) printed surgical osteotomy guides. However, these methods: are usually costly. Here, we introduce a novel method of manufacturing surgical guides built from inexpensive, easy-to-use, and sterilizable dental impression silicone. METHODS: Mandibular and fibular models were prepared using a 3D printer for 10 patients undergoing free fibula flap transfer after mandibular resection. During preoperative simulation surgery, Protesil labor, a dental silicone, was molded to the same size as the fibular models to act as surgical guides. RESULTS: The authors compared pre- and post-operative bone angles and bone lengths for all cases using simulation surgery models and postoperative 3D computed tomography. Mean bone angle difference was 2.6° and mean bone length difference was 1.7 mm. Cost of the dental silicone was approximately US$5/patient. CONCLUSIONS: In our series this method allowed the surgeon to perform an accurate osteotomy, inexpensively and time-efficiently.

Utilization of a Simple Surgical Guide for Multidirectional Cranial Distraction Osteogenesis in Craniosynostosis.

BACKGROUND: Multidirectional cranial distraction osteogenesis (MCDO) can achieve a desired shape for deformities of the cranium. In the past, visual estimation was used to reflect on the actual skull, but it was time-consuming and inaccurate. Here we demonstrate an effective osteotomy navigation method using surgical guides made from a dental impression silicone. METHODS: Seven patients who underwent MCDO between August 2013 and September 2016 were included in the study. Five cases involved utilization of the surgical guide for osteotomy. Three-dimensional (3D) printed cranium models were made using 3D computed tomography (3DCT) imaging data and dental impression silicone sheets were molded using the printed cranium models. These surgical guides were sterilized and used for intraoperative osteotomy design. Vertical distance between nasion/porion and osteotomy lines were calculated using 3D printed cranial models and postoperative 3DCT images to assess reproducibility. RESULTS: The average surgical time/design time was 535/37.0 minutes for the nonsurgical guide group and 486.8/11.8 minutes for the surgical guide group (SG).Treatment using the surgical guide was significantly shorter in terms of operative time and time required for design. For the vertical distance comparison, the average distance was 5.7mm (SD = 0.3) in the non-SG and 2.5mm (SD = 0.44) in the SG, and SG was more accurate. CONCLUSIONS: Shorter operative times and higher reproducibility rates could be achieved by using the proposed surgical guide, which is accurate, low-cost, and easily accessible.

High-Glucose Conditions Promote Anchorage-Independent Colony Growth in Human Breast Cancer MCF-7 Cells.

Previous studies have shown that hyperglycemia is connected to the malignant progression of breast cancer; however, the effects of hyperglycemia on tumorigenic potential in breast cancer cells are largely unknown. Here, we demonstrated that the ability of the human breast cancer cell line MCF-7 to undertake anchorage-independent colony growth was significantly enhanced when cultured under high-glucose conditions compared with that under physiological glucose conditions. The high-glucose conditions also promoted phosphorylation of Akt, suggesting that MCF-7 cells cultured in these conditions acquired an increased ability to undergo anchorage-independent growth at least in part through Akt activation, which has been linked to the development of breast cancer. These results raise the possibility that regulation of Akt activity contributes to the tumorigenesis of breast cancer under high-glucose conditions, and we propose that additional analyses of high glucose-induced tumor formation would provide novel strategies for the diagnosis and therapy of breast cancer with hyperglycemia.

Potential Roles of GLUT12 for Glucose Sensing and Cellular Migration in MCF-7 Human Breast Cancer Cells Under High Glucose Conditions.

BACKGROUND/AIM: Recent reports have indicated that hyperglycaemia is associated with breast cancer progression. High glucose conditions corresponding to hyperglycaemia significantly promote migration of MCF-7 human breast cancer cells, however, little is known about the mechanisms of glucose sensing for the acquisition of migratory properties by MCF-7 cells. This study investigated glucose sensing and mediation, which are responsible for the high motility of MCF-7 cells. MATERIALS AND METHODS: We evaluated the migration of MCF-7 cells cultured in high glucose-containing medium and essential regulatory factors from the perspective of the glucose transport system. RESULTS: We demonstrated that glucose transporter 12 (GLUT12) protein level increased in MCF-7 cells and co-localized with actin organization under high glucose conditions. Moreover, GLUT12-knockdown completely abrogated high glucose-induced migration, indicating that GLUT12 functionally participates in sensing high glucose concentrations. CONCLUSION: GLUT12 plays a critical role in the model of breast cancer progression through high glucose concentrations.

Zinc and its transporter ZIP6 are key mediators of breast cancer cell survival under high glucose conditions.

Recent studies have shown that hyperglycaemia is related to breast cancer progression; however, the mechanisms underlying the relationship between hyperglycaemia and breast cancer cell survival remain unknown. Here, we demonstrate that as compared to physiological glucose conditions, high glucose conditions promote a significant increase in MCF-7 cell survival under hypoxia. High glucose levels inhibit apoptosis and induce epithelial-to-mesenchymal transition, resulting in increased cell viability under hypoxic conditions. Moreover, high glucose-treated cells display significant increases in intracellular Zn2+ levels and reduction in mRNA expression of the zinc (Zn) transporter Zrt- and Irt-like protein 6 (ZIP6) in hypoxia. ZIP6 deficiency disturbs intracellular Zn2+ homeostasis, leading to increased cell survival in hypoxia and reduced E-cadherin expression, indicating that decreased ZIP6 expression is strongly associated with resistance to hypoxia.

A Power-Law Growth and Decay Model with Autocorrelation for Posting Data to Social Networking Services.

We propose a power-law growth and decay model for posting data to social networking services before and after social events. We model the time series structure of deviations from the power-law growth and decay with a conditional Poisson autoregressive (AR) model. Online postings related to social events are described by five parameters in the power-law growth and decay model, each of which characterizes different aspects of interest in the event. We assess the validity of parameter estimates in terms of confidence intervals, and compare various submodels based on likelihoods and information criteria.

High glucose level promotes migration behavior of breast cancer cells through zinc and its transporters.

BACKGROUND: The diabetes patients have been associated with an increased risk of mortality by breast cancer and there are difference between the breast cancer patients with diabetes, and their nondiabetic counterparts in the regimen choice and effects of breast cancer treatment. However, the pathophysiological relationships of diabetes and breast cancer have not yet been elucidated in detail. In this study, we investigate the breast cancer cell line, MCF-7 motility, which linked to invasion and metastasis, in high glucose level corresponding to hyperglycemia and the role of Zn and its transporter. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrated the significant motility of MCF-7 cultured in hyperglycemic level (25 mM glucose) in comparison to normal physiological glucose level (5.5 mM glucose). The other hand, the osmotic control medium, 5.5 mM glucose with 19.5 mM mannitol or fructose had no effect on migratory, suggesting that high glucose level promotes the migration of MCF-7. Moreover, the activity of intracellular Zn(2+) uptake significantly increased in high glucose-treated cells in comparison to 5.5 mM glucose, and the mRNA expression of zinc transporters, ZIP6 and ZIP10, was upregulated in 25 mM glucose-treated cells. The deficiency of ZIP6 or ZIP10 and intracellular Zn(2+) significantly inhibited the high migration activity in 25 mM glucose medium, indicating that Zn(2+) transported via ZIP6 and ZIP10 play an essential role in the promotion of cell motility by high glucose stimulation. CONCLUSION/SIGNIFICANCE: Zinc and its transporters, ZIP6 and ZIP10, are required for the motility stimulated with high glucose level. These findings provide the first evidence proposing the novel strategies for the diagnosis and therapy of breast cancer with hyperglycemia.