Exposure Of Carotid Artery Research Articles

Transcranial near-infrared light promotes remyelination through AKT1/mTOR pathway to ameliorate postoperative neurocognitive disorder in aged mice.

Postoperative neurocognitive disorder (PND) is a prevalent complication following surgery and anesthesia, characterized by progressive cognitive decline. The precise etiology of PND remains unknown, and effective targeted therapeutic strategies are lacking. Transcranial near-infrared light (tNIRL) has shown potential benefits for cognitive dysfunction diseases, but its effect on PND remains unclear. Our previous research indicated a close association between demyelination and PND. In other central nervous system (CNS) disorders, tNIRL has been demonstrated to facilitate remyelination in response to demyelination. In this study, we established the PND model in 18-month-old male C57BL/6 mice using isoflurane anesthesia combined with left common carotid artery exposure. Following surgery, PND-aged mice were subjected to daily 2.5-minute tNIRL treatment at 810 nm for three consecutive days. Subsequently, we observed that tNIRL significantly improved cognitive performance and reduced inflammatory cytokine levels in the hippocampus of PND mice. Furthermore, tNIRL increased the expression of oligodendrocyte transcription factor 2 (OLIG2) and myelin basic protein (MBP), promoting remyelination while enhancing synaptic function-associated proteins such as synaptophysin (SYP) and postsynaptic density protein 95 (PSD95). Further investigation revealed that tNIRL may activate the AKT1/mTOR pathway to facilitate remyelination in PND mice. These findings indicate that tNIRL is a novel non-invasive therapeutic approach for treating PND.

GDNF facilitates cognitive function recovery following neonatal surgical-induced learning and memory impairment via activation of the RET pathway and modulation of downstream effectors PKMζ and Kalirin in rats

ObjectiveThe aim of this study is to elucidate the underlying mechanism through which glial cell line-derived neurotrophic factor (GDNF) improves cognitive deficits in adults resulting from neonatal surgical interventions. MethodsNewborn Sprague–Dawley rats, regardless of gender, were randomly allocated into seven groups on postnatal day 7 as follows (n=15): (1) Control group (not subjected to anesthesia, surgery, or any pharmaceutical interventions); (2) GDNF group (received intracerebroventricular injection of GDNF); (3) Surgery group (underwent right carotid artery exposure under anesthesia with 3 % sevoflurane); (4) Surgery plus GDNF group; (5) Surgery plus GDNF and type II JAK inhibitor NVP-BBT594 (BBT594) group (administered intraperitoneal injection of BBT594); (6) BBT group; and (7) Surgery plus BBT group. Starting from postnatal day 33, all rats underwent Barnes maze and fear conditioning tests, followed by decapitation under sevoflurane anesthesia for subsequent analyses. The left hemibrains underwent Golgi staining, while the right hemibrains were used for hippocampal protein extraction to assess Protein kinase Mζ (PKMζ) and Kalirin expression through western blotting. ResultsGDNF demonstrated a mitigating effect on spatial learning and memory impairment, as well as context-related fear memory impairment, reductions in dendritic total lengths, and spinal density within the hippocampus induced by surgical intervention. Notably, all of these ameliorative effects of GDNF were reversed upon administration of the RET inhibitor BBT594. Additionally, GDNF alleviated the downregulation of protein expression of PKMζ and Kalirin in the hippocampus of rats subjected to surgery, subsequently reversed by BBT594. ConclusionThe effective impact of GDNF on learning and memory impairment caused by surgical intervention appears to be mediated through the RET pathway. Moreover, GDNF may exert its influence by upregulating the expression of PKMζ and Kalirin, consequently enhancing the development of dendrites and dendritic spines.

Clinical and MRI risk factors predicting post-irradiation carotid blowout syndrome in patients with nasopharyngeal cancer.

To explore the clinical and imaging features of nasopharyngeal cancer (NPC) complicated by acute carotid blowout syndrome (CBS), analyze the risk factors for CBS, and improve diagnostic vigilance for early intervention. This retrospective review was conducted between January 2003 and May 2023. Altogether, 49patients with post-irradiation NPC with CBS and 49patients without CBS as control group were enrolled. The condition of the patients when CBS occurred was reviewed. Patient characteristics of the CBS and control groups were compared, and binary logistic regression analysis was performed to identify risk factors for CBS. All patients in the CBS group were conscious, and 41patients had aKarnofsky performance assessment scale score of ≥ 70. After interventional therapy, 43patients survived (the mean survival time of patients after CBS was 3.2 ± 2.1years). Compared with the control group, the CBS group had ahigher incidence of sphenoid sinusitis (81% vs. 52.4%), osteonecrosis (82.9% vs. 51.2%), artery exposure (29.3% vs. 4.9%), and internal carotid artery injury (61% vs. 29.3%). Osteonecrosis and artery exposure were selected as important risk factor for CBS, with p-values of 0.016 and 0.031, respectively. CBS is an important factor that affects the survival of patients with NPC. If internal carotid artery injury, artery exposure, sphenoid sinusitis, and osteonecrosis are present, especially the latter two signs, the possibility of CBS should be considered.

C8-ceramide modulates microglia BDNF expression to alleviate postoperative cognition dysfunction via PKCδ/NF-κB signaling pathway

Postoperative cognitive dysfunction (POCD) is a kind of serious postoperative complication in surgery with general anesthesia and it may affect patients’ normal lives. Activated microglia are thought to be one of the key factors in the regulation of POCD process. Once activated, resident microglia change their phenotype and secrete kinds of cytokines to regulate inflammatory response in tissues. Among these secretory factors, brain-derived neurotrophic factor (BDNF) is considered to be able to inhibit inflammation response and protect nervous system. Therefore, the enhancement of BDNF expression derived from resident microglia is suggested to be potential treatment for POCD. In our study, we focused on the role of C8-ceramide (a kind of interventional drug) and assessed its regulatory effect on improving the expression of BDNF secreted from microglia to treat POCD. According to the results of our study, we observed that C8-ceramide stimulated primary microglia to up-regulate the expression of BDNF mRNA after being treated with lipopolysaccharide (LPS) in vitro. We proved that C8-ceramide had ability to effectively improve POCD of mice after being accepted carotid artery exposure and their abnormal behavior recovered better than that of mice from the surgery group. Furthermore, we also demonstrated that C8-ceramide enhanced the cognitive function of mice via the PKCδ/NF-κB signaling pathway. In general, our study has confirmed a potential molecular mechanism that led to the occurrence of POCD caused by surgery and provided a new clinical strategy to treat POCD.

A quantitative comparative surgical analysis of the endoscopic transorbital approach and frontotemporal-orbitozygomatic approach for extradural exposure of the cavernous sinus.

Recently, the endoscopic superior eyelid transorbital approach (SETA) has emerged as a potential alternative to access the cavernous sinus (CS). Several previous studies have attempted to quantitatively compare the traditional open anterolateral skull base approaches with transorbital exposure; however, these comparisons have been limited to the area of exposure provided by the bone opening and trajectory, and fail to account for the main avenues of exposure provided by subsequent requisite surgical maneuvers. The authors quantitatively compare the surgical access provided by the frontotemporal-orbitozygomatic (FTOZ) approach and the SETA following applicable periclinoid surgical maneuvers, evaluate the surgical exposure of key structures in each, and discuss optimal approach selection. SETA and FTOZ approaches were performed with subsequent applicable surgical maneuvers on 8 cadaveric heads. The lengths of exposure of cranial nerves (CNs) II-VI and the cavernous internal carotid artery; the areas of the space accessed within the supratrochlear, infratrochlear, and supramaxillary (anteromedial) triangles; the total area of exposure; and the angles of attack were measured and compared. Exposure of the extradural CS was comparable between approaches, whereas access was significantly greater in the FTOZ approach compared with the SETA. The lengths of extradural exposure of CN III, V1, V2, and V3 were comparable between approaches. The FTOZ approach provided marginally increased exposure of CNs IV (20.9 ± 2.36 mm vs 13.4 ± 3.97 mm, p = 0.023) and VI (14.1 ± 2.44 mm vs 9.22 ± 3.45 mm, p = 0.066). The FTOZ also provided significantly larger vertical (44.5° ± 6.15° vs 18.4° ± 1.65°, p = 0.002) and horizontal (41.5° ± 5.40° vs 15.3° ± 5.06°, p < 0.001) angles of attack, and thus significantly greater surgical freedom, and provided significantly greater access to the supratrochlear (p = 0.021) and infratrochlear (p = 0.007) triangles, and significantly greater exposure of the cavernous internal carotid artery (17.2 ± 1.70 mm vs 8.05 ± 2.37 mm, p = 0.001). Total area of exposure was also significantly larger in the FTOZ, which provided wide access to the lateral wall of the CS as well as the possibility for intradural access. This is the first study to quantitatively identify the relative advantages of the FTOZ and transorbital approaches at the target region following requisite surgical maneuvers. Understanding these data will aid in selecting an optimal approach and maneuver set based on target lesion size and location.

The neuroprotective effect of near infrared light therapy in aged mice with postoperative neurocognitive disorder by upregulating IRF7

BackgroundPostoperative neurocognitive disorder (PND) is a common central nervous system complication after undergoing surgery and anesthesia especially in elderly patients, while the therapeutic options are very limited. This study was carried out to investigate the beneficial effects of transcranial near infrared light (NIRL) which was employed to the treatment of PND and propose the involved mechanisms. MethodsThe PND mice were established through left carotid artery exposure under isoflurane anesthesia and received transcranial NIRL treatment. Behavioral testing was performed to evaluate the cognitive function of PND mice after transcranial NIRL therapy. Changes in the transcriptomic profiles of prefrontal cortex (PFC) and hippocampus (HP) were identified by next generation sequencing (NGS), and the molecular mechanisms involved were examined by both in vivo mouse model and in vitro cell culture studies. ResultsWe found that transcranial NIRL therapy effectively ameliorated learning and memory deficit induced by anesthesia and surgery in aged mice. Specifically, we identified down-regulation of interferon regulatory factor 7 (IRF7) in the brains of PND mice that was mechanistically associated with increased pro-inflammatory M1 phenotype of microglia and elevated neuroinflammatory. NIRL treatment produced protective effects through the upregulation of IRF7 expression and reversing microglial phenotypes from pro-inflammatory to neuroprotective, resulting in reduced brain damage and improved cognitive function in PND mice. ConclusionOur results indicate that transcranial NIRL is an effective and safe therapy for PND via alleviating neuroinflammation, and IRF7 plays a key transcription factor in regulating the M1-to-M2 switch of microglia.

Transorbital Exposure of the Internal Carotid Artery: A Detailed Anatomic and Quantitative Roadmap for Safe Successful Surgery.

The superior eyelid endoscopic transorbital approach has rapidly gained popularity among neurosurgeons for its advantages in the treatment, in a minimally invasive fashion, of a large variety of skull base pathologies. In this study, an anatomic description of the internal carotid artery (ICA) is provided to identify risky zones related to lesions that may be approached using this technique. In this framework, a practical roadmap can help the surgeon to avoid potentially life-threatening iatrogenic vascular injuries. Eight embalmed adult cadaveric specimens (16 sides) injected with a mixture of red latex and iodinate contrast underwent superior eyelid transorbital endoscopic approach, followed by interdural dissection of the cavernous sinus, extradural anterior clinoidectomy, and anterior petrosectomy, to expose the entire "transorbital" pathway of the ICA. Furthermore, the distance of each segment of the ICA explored by means of the superior eyelid endoscopic transorbital approach was quantitatively analyzed using a neuronavigation system. We exposed 4 distinct ICA segments and named the anatomic window in which they are displayed in accordance with the cavernous sinus triangles distribution of the middle cranial fossa: (1) clinoidal (Dolenc), (2) infratrochlear (Parkinson), (3) anteromedial (Mullan), and (4) petrous (Kawase). Critical anatomy and key surgical landmarks were defined to further identify the main danger zones during the different steps of the approach. A detailed knowledge of the reliable surgical landmarks of the course of the ICA as seen through an endoscopic transorbital route and its relationship with the cranial nerves are essential to perform a safe and successful surgery.

Use of a prosthetic conduit for stent delivery in transcarotid artery revascularization for patients with unfavorable anatomy.

Transcarotid artery revascularization (TCAR) provides a safe alternative to carotid endarterectomy. The anatomic requirements include a 5-cmminimum clavicle to carotid bifurcation distance for sheath access proximal to the lesion. In the present report, we describe our experience with conduit use for patients not meeting that requirement. Patients undergoing elective TCAR with a conduit from 2021 to 2022 were retrospectively identified. After carotid artery exposure, a 6-mm prosthetic graft was anastomosed to the common carotid artery in an end-to-side fashion. After stent delivery, the conduit was ligated and oversewn. The patient demographics, procedural details, and outcomes were recorded and compared with our nonconduit TCAR experience. A total of 11 patients (64% male; age, 75± 5years) underwent TCAR with a conduit, 5 (46%) for symptomatic disease, and 77 patients underwent TCAR with no conduit, 52 (60%) with symptomatic disease (P= .50). Other than a higher rate of prior coronary interventions in the conduit group (55% vs 47%; P= .007), no significant differences were found in age, gender, race, comorbidities, or high risk for carotid endarterectomy criteria. In the conduit group, the average skin to carotid artery depth was 4.2cm (range, 1.9-6.1cm). The average clavicle to bifurcation distance was 4.4cm (range, 3.3-4.9cm) vs 6.5cm (range, 3.3-9.7cm; P= .002) in the nonconduit group. Dacron was the most common conduit material used (73%). No differences were found in the mean procedure times (121± 32 vs 129± 53minutes; P= .785) or flow reversal times (14± 5 vs 19± 13minutes; P=.989) for the conduit and nonconduit cohorts, respectively. Technical success was achieved in 100% of the conduit and nonconduit cases. Excluding one outlier of a prolonged stay (7days) for management of unrelated medical issues (gastrostomy tube placement for chronic dysphagia after mass resection and neck radiation), the mean hospital stay was 2days (1.2± 0.4 intensive care unit days) compared with 3.8± 5.7days for our nonconduit cohort (P= .2). Hypotension was the most common reason for delayed discharge for the conduit group (n=3; 27%). The average follow-up was 2.7months (range, 1-10months). For all 11 conduit patients, the stent remained patent without stenosis, thrombus, or pseudoaneurysm at the conduit stump site on surveillance duplex ultrasound. No strokes or complications had occurred at 30days in the conduit group compared with four strokes or transient ischemic attacks (P= .469) and 18 minor complications in the nonconduit group (P= .091). For patients lacking a sufficient distance between the clavicle and carotid artery bifurcation, a prosthetic conduit facilitates safe use of flow reversal for stent delivery and can be ligated at procedural completion without consequences.

Formyl peptide receptor 1 is involved in surgery-induced neuroinflammation and dysfunction of learning and memory in mice

Postoperative cognitive dysfunction (POCD) is a common complication after surgery. Peripheral immune cells may contribute to the development of POCD. However, molecules that are important for this contribution are not known. We hypothesize that formyl peptide receptor 1 (FPR1), a molecule critical for the migration of the monocytes and neutrophils into the brain after brain ischemia, is central to the development of postoperative neuroinflammation and dysfunction of learning and memory. Male C57BL/6 (wild-type) mice and FPR1-/- mice received right carotid artery exposure surgery. Some wild-type mice received cFLFLF, an FPR1 antagonist. Mouse brains were harvested 24 h after the surgery for biochemical analysis. Mice were subjected to the Barnes maze and fear conditioning tests to determine their learning and memory from 2 weeks after the surgery. We found that surgery increased FPR1 in the brain and proinflammatory cytokines in the blood and brain of wild-type mice. Surgery also impaired their learning and memory. cFLFLF attenuated these effects. Surgery did not induce an increase in the proinflammatory cytokines and impairment of learning and memory in FPR1-/- mice. These results suggest that FPR1 is important for the development of neuroinflammation and dysfunction of learning and memory after surgery. Specific interventions that inhibit FPR1 may be developed to reduce POCD.

Familiar observers attenuate surgery-induced neuroinflammation and cognitive dysfunction in mice.

Postoperative cognitive dysfunction (POCD) is a common complication associated with poor outcome. Our previous study has shown that living with familiar observers in the same cage reduces anxiety of mice with surgery. Anxiety can impair learning and memory. Thus, this study was designed to determine whether living with familiar observers attenuated the dysfunction of learning and memory of mice with surgery. Six- to eight-week-old CD-1 male mice or 18-month-old C57BL/6 male mice had left carotid artery exposure under isoflurane anesthesia. They lived with non-surgery male mice at 2 (number of surgery mice) to 3 (number of non-surgery mice) ratio or with other surgery mice. Mice were subjected to light and dark box test 3 days after surgery to measure their anxiety levels and novel object recognition and fear conditioning tests from 5 days after surgery to measure their learning and memory. Blood and brain were harvested for biochemical analysis. Living with familiar observers that lived with surgery mice for at least 2 weeks before the surgery and then after surgery reduced the anxiety and dysfunction of learning and memory in young adult male mice. Living with unfamiliar observers that lived with surgery mice after the surgery but not before the surgery did not have those effects on the mice with surgery. Living with familiar observers attenuated learning and memory dysfunction after surgery also in old male mice. Living with familiar observers attenuated inflammatory response in the blood and brain and the activation of the lateral habenula (LHb)-ventral tegmental area (VTA) neural circuitry, which has been shown to be important for POCD. Wound infiltration with bupivacaine attenuated the activation of LHb-VTA. These results suggest that living with familiar observers attenuates POCD and neuroinflammation, possibly via inhibiting the activation of the LHb-VTA neural circuitry.

Neurometabolic and structural alterations of medial septum and hippocampal CA1 in a model of post-operative sleep fragmentation in aged mice: a study combining 1H-MRS and DTI.

Post-operative sleep disturbance is a common feature of elderly surgical patients, and sleep fragmentation (SF) is closely related to post-operative cognitive dysfunction (POCD). SF is characterized by sleep interruption, increased number of awakenings and sleep structure destruction, similar to obstructive sleep apnea (OSA). Research shows that sleep interruption can change neurotransmitter metabolism and structural connectivity in sleep and cognitive brain regions, of which the medial septum and hippocampal CA1 are key brain regions connecting sleep and cognitive processes. Proton magnetic resonance spectroscopy (1H-MRS) is a non-invasive method for the evaluation of neurometabolic abnormalities. Diffusion tensor imaging (DTI) realizes the observation of structural integrity and connectivity of brain regions of interest in vivo. However, it is unclear whether post-operative SF induces harmful changes in neurotransmitters and structures of the key brain regions and their contribution to POCD. In this study, we evaluated the effects of post-operative SF on neurotransmitter metabolism and structural integrity of medial septum and hippocampal CA1 in aged C57BL/6J male mice. The animals received a 24-h SF procedure after isoflurane anesthesia and right carotid artery exposure surgery. 1H-MRS results showed after post-operative SF, the glutamate (Glu)/creatine (Cr) and glutamate + glutamine (Glx)/Cr ratios increased in the medial septum and hippocampal CA1, while the NAA/Cr ratio decreased in the hippocampal CA1. DTI results showed post-operative SF decreased the fractional anisotropy (FA) of white matter fibers in the hippocampal CA1, while the medial septum was not affected. Moreover, post-operative SF aggravated subsequent Y-maze and novel object recognition performances accompanied by abnormal enhancement of glutamatergic metabolism signal. This study suggests that 24-h SF induces hyperglutamate metabolism level and microstructural connectivity damage in sleep and cognitive brain regions in aged mice, which may be involved in the pathophysiological process of POCD.

Endoplasmic Reticulum Stress-Activated Neuronal and Microglial Autophagy Contributes to Postoperative Cognitive Dysfunction in Neonatal rats.

Surgery and anesthesia in neonates may lead to cognitive impairment or abnormal behaviors. It has been shown that autophagy plays a critical role in neuropsychiatric disorders, while the role of autophagy in postoperative cognitive impairment in neonates is not known. Here, we determined this role and the involvement of endoplasmic reticulum (ER) stress in regulating brain cell autophagy after surgery. Seven-day old neonatal rats (P7) had right common carotid artery exposure under anesthesia with 3% sevoflurane for 2h. Learning and memory were tested using Barnes maze (BM) and fear conditioning (FC) on P31-42 and P42-44, respectively. In another experiment, rat brains were harvested for biochemical studies. The ratio of microtubule-associated protein 1 light chain 3 (LC3) BII/I was increased and sequestosome 1 (P62/SQSTM1) levels were decreased in the brain 24h after surgery and anesthesia in neonatal rats. Immunofluorescent staining of LC3B was co-localized with a neuronal or a microglial marker but was not co-localized with a marker for astrocytes in rats with surgery. These rats had a poorer performance in the BM and FC tests than control rats when they were adolescent. Pretreatment with an autophagy inhibitor, 3-methyladenine, attenuated the poor performance. Surgery and anesthesia increased the expression of 78kDa glucose-regulated protein (BIP/GRP78), an indicator of ER stress, 6h after surgery and anesthesia. The ER stress activator tunicamycin and inhibitor tauroursodeoxycholic acid increased the markers for autophagy in control rats and decreased the autophagy markers in rats with surgery, respectively. Our results suggest that surgery in neonatal rats induces ER stress that then activates neuronal and microglial autophagy, which contributes to learning and memory impairment later in life.

Transcranial near-infrared laser improves postoperative neurocognitive disorder in aged mice via SIRT3/AMPK/Nrf2 pathway.

Postoperative neurocognitive disorder (PND) is a common central nervous system (CNS) complication that might increase the morbidity and mortality of elderly patients after anesthesia/surgery. Neuroinflammation, oxidative stress, and synaptic dysfunction are closely related to cognitive dysfunction, an important clinical feature of PND. Transcranial near-infrared laser (TNIL) is regarded as an effective treatment for cognitive-related diseases by improving mitochondrial function and alleviating neuroinflammation and oxidative stress damage. Aged male C57BL/6 mice underwent a carotid artery exposure procedure under isoflurane anesthesia. We treated PND-aged mice for three consecutive days (4 h post-operation, 1-laser) with 810 nm continuous wave (CW) laser 18 J/cm2 at 120 mW/cm2. The post-treatment evaluation included behavioral tests, RTq-PCR, immunofluorescence, and Western blot. The results demonstrated that TNIL improved PND and the levels of synaptic function-associated proteins such as post-synaptic density protein 95 (PSD95), synaptophysin (SYP), and brain-derived neurotrophic factor (BDNF). Besides, neuroinflammatory cytokine levels of tumor necrosis factor (TNF)-α and interleukin (IL)-1β as well as microglia activation and oxidative stress damage were attenuated after TNIL treatment in aged mice with PND. Further investigation suggested that TNIL relieved oxidative stress response by activating the SIRT3/AMPK/Nrf2 pathway. Transcranial near-infrared laser improved cognitive impairment in aged mice with PND, which may be a promising therapeutic for PND.

Inhibition of ERK/CREB signaling contributes to postoperative learning and memory dysfunction in neonatal rats.

Exposure to surgery with anesthesia early in life may lead to abnormal behavior, learning, and memory in humans. Pre-clinical studies have suggested a critical role of glial cell-derived neurotrophic factor (GDNF) in these effects. We hypothesize that the inhibition of extracellular signal-regulated kinase (ERK)-cAMP response element-binding protein (CREB) pathway contributes to GDNF decrease and the dysfunction of learning and memory. To address this hypothesis, 7-day-old Sprague-Dawley male and female rats were subjected to right carotid artery exposure (surgery) under sevoflurane anesthesia. Their learning and memory were tested by the Barnes maze, and novel object recognition tests started 23days after the surgery. Blood and brain were harvested at various times after surgery for biochemical analyses. Rats with surgery and anesthesia performed poorly in the Barnes maze and novel object recognition tests compared with control rats. Rats with surgery had a decreased GDNF concentration in the brain and urine. The concentrations of urine GDNF were negatively correlated with the performance of rats in a delayed memory phase of the Barnes maze test. Surgery increased proinflammatory cytokines in the blood and brain. Intracerebroventricular injection of GDNF attenuated the increased inflammatory response in surgery rats. Surgery inhibited ERK and CREB. Inhibiting ERK reduced GDNF and induced poor performance in the Barnes maze and novel object recognition tests of rats without surgery. Surgery also increased brain-derived natriuretic peptide (BNP) in the brain. Intracerebroventricular injection of BNP inhibited ERK and CREB, reduced GDNF, and impaired learning and memory. Surgery, ERK inhibition, and BNP reduced the expression of synaptic proteins. Our results suggest that surgery increases BNP that inhibits ERK-CREB signaling to reduce GDNF, which leads to an unbalanced inflammatory response and a reduced synaptic protein expression for the development of postoperative cognitive dysfunction. KEY MESSAGES: Surgery increases BNP and decreases ERK/CREB signaling to reduce GDNF. The increase in BNP and decrease in ERK/CREB signaling contribute to postoperative cognitive dysfunction. GDNF reduction contributes to neuroinflammatory response after surgery. Urine GDNF concentrations are negatively corrected with poor spatial memory performance.

Flap Application in Reconstructive Surgery to Manage Severe Radiation-induced Ulcers: A Case Series

Introduction. Radiation-induced ulceration is a late-stage skin reaction after RT for cancer treatment. Objective. The present study examined the use of a single-stage reconstructive procedure to manage radiation-related wounds. Materials and Methods. Nine patients with radiation-induced chronic ulcer with accompanying severe complications were admitted to the Plastic, Reconstructive, and Regenerative Center of Viet Nam National Burn Hospital between October 2015 and September 2019. The patients ranged in age from 49 to 77 years. Complications included exposed cheekbone (n = 1), exposed trachea (n = 1), exposed carotid artery (n = 2), exposed axillary artery (n = 2), exposed pleura (n = 1), and exposed pericardium (n = 2). Flap type used to achieve defect coverage after debridement was individualized to each patient and included ALT, LD, SCA, and DIEP flaps. Additionally, a high-density polyethylene was used to reconstruct the trachea to recover breathing function in the patient with exposed trachea. Results. Complete survival of all flaps was achieved. Most vital organs (the trachea, axillary artery, and carotid artery) were covered. Hospital length of stay ranged from 15 to 120 days. Conclusions. The successful management of patients with severe complications suggests that immediate single-stage reconstruction may be a valuable option for managing radiation-induced ulcers.

Femoral artery collapse ratio as an indicator of chest compression quality during cardiopulmonary resuscitation in a porcine cardiac arrest model

Cardiopulmonary resuscitation (CPR) quality is crucial for improving patient survival rates after cardiac arrest. This study aimed to investigate the usefulness of femoral artery collapse ratio (systolic diameter/diastolic diameter ratio) measurement using M-mode ultrasound versus end-tidal carbon dioxide (ETCO2) for the assessment of high-quality CPR in a porcine cardiac arrest model. A total of 10 male mongrel pigs (age range, 16–20 weeks; weight, 45–50 kg) were used. After anesthesia, the carotid artery was dissected and exposed. The animals were instrumented with an arterial catheter in the exposed carotid artery to monitor arterial blood pressure. Cardiac arrest was induced by injecting potassium chloride (KCl, 40 equivalents of weight). The animals underwent chest compression using a mechanical device, and the chest compression depth and ETCO2 were measured using a defibrillator. To obtain hemodynamic information, two investigators performed an ultrasound examination on both femoral arteries. One examiner measured the femoral peak systolic velocity (PSV), while the other measured the diameters of the femoral artery (systolic diameter and diastolic diameter) in a transverse or longitudinal position using the M-mode of the linear ultrasound probe. As the compression depth increased, ETCO2, femoral artery diameter, collapse ratio (systolic diameter/diastolic diameter), and blood flow increased; however, PSV decreased. The ETCO2 and collapse ratio were positively correlated. The femoral artery collapse ratio, measured using the M-mode ultrasound, could be an alternative and simple method to evaluate high-quality CPR.

Endoscopic trans‐lateral oropharyngeal wall approach to the petrous apex and the petroclival region

A trans-lateral oropharyngeal wall approach (TLOWA) to the petrous apex has not been previously defined. This study aims to assess the feasibility of a TLOWA for surgical access to the petrous apex and the petroclival region. An endoscopic TLOWA for exposure of the petrous apex and petroclival region was performed on five cadaveric specimens (10 sides). Associated anatomical landmarks were defined, and the strategies for maximal exposure of the internal carotid artery (ICA) were explored. Via a TLOWA, the parapharyngeal ICA was widely exposed in all 10 sides. Following transection of the Eustachian tube, the inferior petrous apex and petroclival region could be sufficiently exposed. After drilling the anteroinferior bony canal, the horizontal petrous ICA, foramen lacerum, and the paraclival ICA could be adequately revealed. The TLOWA may provide an alternative corridor for access to the petrous apex and the petroclival region. The parapharyngeal, petrous, lower paraclival ICAs, and the foramen lacerum could be adequately exposed via the TLOWA.

Intraoperative Angiogram Using C-Arm Fluoroscopy and Direct Common Carotid Artery Puncture During Surgical Treatment of Paraclinoid Aneurysms

Intraoperative angiography (IOA) has been shown to be a useful adjunct in surgical treatment of cerebral aneurysms. However, its use can be limited by hybrid operating room availability. On the other hand, the use of C-arm fluoroscopy can add challenges to IOA during navigation of the aortic arch and selection of the great vessels. We aimed to describe a simple method of IOA that can be applied during surgery of paraclinoid aneurysms and can be performed in a normal operating room without the need to navigate the aortic arch. In patients undergoing surgery for paraclinoid aneurysms with need for cervical carotid artery exposure, IOA was performed using a single plane C-arm fluoroscopy unit after direct puncture of the carotid artery. Five patients were included: 2 with subarachnoid hemorrhage, 2 with unruptured aneurysm and history of subarachnoid hemorrhage, and 1 with unruptured aneurysm. There were 2 internal carotid blister aneurysms, 2 ophthalmic artery aneurysms, and 1 superior hypophyseal artery aneurysm. IOA was performed using direct carotid puncture through the neck incision required for proximal control. In all cases, intraoperative images were of sufficient quality to determine the completeness of aneurysm occlusion as well as parent and branching vessel patency. There were no postoperative infarctions and no complications related to IOA. IOA using direct carotid puncture can be performed in a standard operating room with the use of a C-arm, eliminating the need to catheterize the great vessels of the aortic arch.

Postoperative Learning and Memory Dysfunction Is More Severe in Males But Is Not Persistent and Transmittable to Next Generation in Young Adult Rats.

Postoperative cognitive dysfunction (POCD) affects numerous patients each year and is associated with poor outcomes. Currently, the duration of POCD is not known. This preclinical study determined whether POCD was persistent, different between sexes and transmittable to the next generation. Two-month-old Sprague-Dawley rats had left carotid artery exposure under isoflurane anesthesia and their learning and memory were assessed from 5 days, 2 months, and 4 months after surgery. Rats with or without surgery were mated when they were 4 or 6 months old, and the learning and memory of the offspring were tested at 2 months of age. Males exposed to surgery took a longer time to identify the target box after training sessions in a Barnes maze and had less freezing behavior in context-related fear conditioning than control rats when the tests were started 5 days after surgery. Similarly, female rats had a poorer performance than control rats in the Barnes maze test from 5 days after surgery. However, these poorer performances were not observed when the tests were administered 2 or 4 months after surgery. The offspring of rats with surgery had a performance similar to that of the offspring of control rats. Our results suggest that both male and female rats develop POCD but that the learning and memory dysfunction appears to be more severe in male rats. POCD may not be persistent and does not transmit to the next generation.

Inclusion of a latissimus dorsi segment in an extended lower trapezius musculocutaneous flap facilitates complex defect reconstruction

The pedicled lower trapezius musculocutaneous flap (LTMF) can extend far beyond the lateral border of the trapezius muscle, with a reliable blood supply. However, the distal part of the extended LTMF lacks a muscular component, limiting its usage in complex defect reconstruction, which often requires obliteration of dead space and coverage of vital structures. To overcome this limitation, we modified the LTMF by adding a segment of latissimus dorsi muscle (LDM). Between 2014 and 2021, the modified extended LTMF was used to reconstruct complex defects in the head, neck, shoulder, and contralateral chest wall and back in 19 patients. By preserving the interconnections between the branches of the posterior intercostal arteries, we were able to include various amounts of LDM within the extended LTMF. The LDM component was used to obliterate dead space and repair wounds involving cerebrospinal fluid leakage, infection, radioactive osteomyelitis, exposed carotid artery, lung, and implant materials. The average flap size was 30.7cm × 10.9cm (range: 25 × 8 cm-40 × 14cm). The average size of the LDM was 113.9 cm2 (range: 27.7-216.6 cm2). Partial flap necrosis occurred in two patients and the secondary defects were reconstructed using a local flap. The remaining 17 flaps survived completely. The LTMF carrying a segment of the LDM could be considered for patients undergoing reconstruction of complex defects in the head, neck, shoulder, and contralateral chest wall and back and for patients who are ineligible for free flap reconstruction.