Correction of Eyes and Lip Canting after Bimaxillary Orthognathic Surgery

Patients who have a lower facial asymmetry with compensatory head posture (developmental facial asymmetry) may have minor temporomandibular (T-M) joint problems and tend to mask their asymmetry by tilting the head for camouflage of their chin deviation. However, this compensatory head posture can give the impression of orbital dystopia and c spine deviation. When these patients undergo bimaxillary orthognathic surgery, orbital canting and head tilting improves gradually without the need for camouflage, and bleary eyes become clearer. We evaluated 13 patients who underwent LeFort I osteotomy combined with bilateral sagittal split osteotomy of the mandible for developmental facial asymmetry to quantitatively observe whole facial postural changes after surgery. Pre-operative and post-operative 1:1 full-face photographs of the patients were analyzed to compare the degrees of head tilting and orbital canting and the sizes of the eye opening. After bimaxillary orthognathic surgery, eye canting decreased from 2.6° to 1.5°, eye and lip lines came closer to parallel, and the degree of head tilting decreased from 3.4° to 1.3°. The eyes also appeared to open wider. Correction of lower facial skeletal asymmetry through bimaxillary orthognathic surgery improved head tilting and orbital canting gradually by eliminating the need of compensatory head posture. Facial expressions also changed as the size of the eyes increased due to the reduction of facial muscle tension caused by T-M joint dysfunction.ope

An allometric pharmacokinetic model and minimum effective analgesic concentration of fentanyl in patients undergoing major abdominal surgery

Background: We aimed to characterise the population pharmacokinetics of fentanyl in adults and to determine the minimum effective concentration (MEC) and minimum effective analgesic concentration (MEAC) of i.v. fentanyl in patients after major abdominal open surgery. Methods: In the pharmacokinetic study; subjects received an intravenous bolus of fentanyl 100 μg during operation; and arterial blood was sampled at pre-set intervals. In addition; data from previously published fentanyl pharmacokinetic studies were incorporated to build a pharmacokinetic model. In the MEAC study; subjects were asked to rate their pain every 10 min using a VAS (0=no pain; 10=most severe pain) in the PACU. The first blood sample was obtained when wound pain was rated as ≥3 at rest or ≥5 during compression. Then; fentanyl 50 μg was administered every 10 min until the pain intensity had decreased to <3 at rest and <5 during compression; at which point the second blood was sampled and the first MEAC of fentanyl was measured. The same procedure was repeated to obtain a third sample (MEC) and a fourth sample (second MEAC). Results: In the population pharmacokinetic study (n=95); the plasma concentration of fentanyl over time was well-described by the three-compartment mammillary model using an allometric expression. The V1; V2; V3; Cl; Q1; and Q2 of a 70 kg subject were 10.1; 26.5; 206 L; 0.704; 2.38; and 1.49 L min-1; respectively. In the MEAC study (n=30); the median (inter-quartile range) MEC and MEAC were 0.72 (0.58-1.05) ng ml-1; and 0.99 (0.76-1.28) ng ml-1; respectively. Conclusion: These results provide a scientific basis for the use of fentanyl for acute postoperative pain management in surgical patients.restrictio

최소침습형 뇌피질 인터페이스를 위한 생분해성 및 축변환성 소프트 전자소자 기술

학위논문(박사) -- 서울대학교대학원 : 공과대학 재료공학부, 2024. 2. 강승균.The ability to comprehend the broad spectrum of cortical activity is essential for deciphering the intricate networks of the brain in order to establish precise brain-machine interfaces (BMI) and to develop more focused and efficacious diagnostic and therapeutic strategies for the lesion area. Cortical interfaced electronics with a broad coverage area can furnish extensive information by means of real-time monitoring of physiological data from multiple sites in the brain simultaneously. However, the implantation process for such electronics is heavily reliant on a large area craniotomy, which carries the risk of complications such as neurogenic hypertension or chronic post- craniotomy headache. Moreover, electronic implants require a secondary surgery for removal, which involves a risk of infection and other adverse effects similar to, or even more severe than the initial insertion procedure, and aims to prevent unwanted immune responses, biofilm formation, or migration-induced damage. These high-risk and stressful surgical interventions pose a significant medical and psychological obstacle to the clinical application of BMI and other related fields. In this study, we introduce the automatic deployable and fully biodegradable multifunctional device platform designed to enable extensive brain interfacing while minimizing surgical burden. This platform can be folded and packaged into a minimally invasive tool that requires only a small incision, such as a syringe or catheter (diameter < 5 mm), and can deploy in a programmable manner to cover a much larger area than the incision site within a narrow anatomical space, such as the subdural space, exploiting its axis transformation and shape recovery capability. The integrated electronic devices, including temperature, strain, pH sensors, and ECoG electrodes, are capable of monitoring delicate cues for a specific period of time, and offer wireless capabilities to transmit/receive data via near-field communication. In vivo demonstration of large-area cortical measurement by passive or active multiplexed arrays and wireless monitoring of physiological signal show the minimally invasive cortical interface. Ultimately, all components of the device dissolved by hydrolysis or metabolic activity, eliminating the risk of potential biofilm formation or secondary injury during the removal process. Subsequent biodegradation, which demonstrated by in vivo degradation in rat model, further underscores the potential of this minimally invasive brain-interfacing platform for manipulating large areas.뇌의 복잡한 네트워크를 해독하여 정확한 뇌-기계 인터페이스(BMI)를 구축하고 병변 부위에 대한 보다 집중적이고 효과적인 진단 및 치료 방법을 개발하기 위해서는 피질 활동의 광범위한 스펙트럼을 이해하는 능력이 필수적이다. 광범위한 범위 영역을 가진 피질 인터페이스 전자기기는 뇌의 여러 부위의 생리학적 정보를 동시에 실시간으로 모니터링함으로써 광범위한 정보를 제공할 수 있다. 그러나, 그러한 전자기기의 이식 과정은 신경성 고혈압이나 만성 두개수술 후 두통과 같은 합병증의 위험을 수반하는 넓은 영역 두개수술에 크게 의존한다. 또한, 전자기기를 이식하기 위해서는 초기 삽입 과정과 유사하거나 심지어 더 심각한 감염 및 다른 부작용의 위험을 수반하고 원치 않는 면역 반응, 생물막 형성 또는 이주로 인한 손상을 예방하는 것을 목표로 하는 제거를 위한 2차 수술이 필요하다. 이러한 고위험 및 스트레스가 많은 수술 개입은 BMI 및 기타 관련 분야의 임상 적용에 상당한 의학적 및 심리적 장애를 초래한다. 본 학위 논문에서는 수술 부담을 최소화하면서 광범위한 뇌 인터페이스를 가능하게 하도록 설계된 자동 배포 가능하고 완전 생분해성 다기능 장치 플랫폼을 개발한다. 또한 신축성있는 기계적 물성이 향상된 생분해성 전극물질을 개발함으로써 다양한 변형 또는 반복적인 변형하에서 안정적인 작동이 가능한 생분해성 전자소자로 응용가능한 전극소재를 개발하고자 한다. 이 플랫폼은 주사기 또는 카테터(직경 < 5mm)와 같이 작은 절개만 필요한 최소 침습 도구로 접고 패키지화할 수 있으며, 경막하 공간과 같은 좁은 해부학적 공간 내에서 절개 부위보다 훨씬 더 큰 영역을 덮도록 프로그래밍 가능한 방식으로 배포할 수 있어 축 변환 및 형상 복구 기능을 활용한다. 온도, 변형률, pH 센서 및 ECoG 전극을 포함한 통합 전자 장치는 특정 기간 동안 섬세한 신호를 모니터링할 수 있으며 근거리 통신을 통해 데이터를 송수신할 수 있는 무선 기능을 제공한다. 수동 또는 능동 다중화 어레이에 의한 대면적 피질 측정의 생체 내 시연과 생리학적 신호의 무선 모니터링은 최소 침습적 피질 인터페이스를 보여준다. 궁극적으로 장치의 모든 구성 요소는 가수분해 또는 대사 활동에 의해 용해되어 제거 과정에서 잠재적인 생물막 형성 또는 2차 부상의 위험을 제거합니다. 쥐 모델의 생체 내 분해에 의해 입증된 후속 생분해는 대면적 조작을 위한 이 최소 침습적 뇌 인터페이스 플랫폼의 잠재력을 더욱 강조하고자 한다.Chapter 1. Introduction 1 1.1 Brain interfaced electronics 1.2 Implantable brain interfaces 1.3 Chronic inflammatory response from implantable brain interfaces 1.4 Biodegradable electronics for brain interfaces Chapter 2. Biodegradable and deployable electronic for minimally invasiveness 10 2.1 Motivation 10 2.2 Matierals for deployable and detectable substrate 13 2.2.1 Materials for deployable and detectable substrate 2.2.2 Fabrication of various electronics on deployable substrate 2.2.3 Injection process with controller 2.2.4 Mechanical characterization with finite element analysis 2.3 Overview of biodegradable and deployable electronics platform 21 2.3.1 Overall structure of the platform 2.3.2 Overall process from packaging to biodegradation 2.3.3 Packaging process 2.3.4 Deploying process 2.3.5 Biodegradation 2.4 Mechanical modelling of device packaging and deploying process . 42 2.4.1 Shape fixation and deployment using shape memory polymer 2.4.2 Mechanical modelling of device packaging 2.4.3 Mechanical modelling of device deployment Chapter 3. In vivo demonstration of biodegradable and deployable electronic on canine model 83 3.1 Motivation 83 3.2 Materials and experimental methods . 84 3.2.1 Animal surgery procedure 3.2.2 Manufacturing of transparent skull replica 3.2.3 Synthesis of a UV fluorescence layer for visualization 3.2.4 In vivo imaging for self-deployment and biodegradability 3.2.5 In vivo acute and chronic ECoG recording 3.2.6 Immunohistochemistry 3.2.7 Blood analysis 3.3 In vivo demonstration of deployable platform . 91 3.3.1 In vivo deployment on canine brain 3.3.2 Passive ECoG recordings 3.3.3 Active ECoG recordings 3.3.4 Wireless system for versatile physiological signal monitoring 3.3.5 Biocompatibility and biodegradability 3.4 Conclusion 136 v Chapter 4. Biodegradable metallic glass for stretchable electrode 137 4.1 Motivation . 137 4.2 Materials and experimental methods 139 4.2.1 Formation and characterization of MgZnCa MG films 4.2.2 Dissolution chemistry of MgZnCa MG 4.2.3 In situ micro-tensile testing 4.2.4 Fabrication of electronic devices with a MgZnCa MG electrode 4.2.5 Characterization of stretchability and fatigue behavior 4.2.6 In vitro cell viability test 4.2.7 In vivo evaluation test 4.3 Biodegradable MgZnCa metallic glass 146 4.3.1 Dissolution chemistry and kinetics 4.3.2 Dissolution kinetics depending on solution 4.3.3 Stretchability and fatigue resistivity 4.3.4 Electronics integratability of MgZnCa metallic glass 4.3.5 Biocompatibility 4.4 Conclusion 182 Reference 183 Abstract in Korean 197박

Effects of Hat-Shaped Mortised Genioplasty with Genioglossus Muscle Advancement on Retrogenia and Snoring: Assessment of Esthetic, Functional, and Psychosocial Results

BACKGROUND: An increasing number of patients undergo genioplasty for esthetic purposes to correct micrognathism or retrognathism. However, these conditions are considered an important risk factor for snoring. The purpose of this study was to evaluate both esthetic improvement and functional changes of snoring symptoms in patients who underwent hat-shaped mortised advancing genioplasty with genioglossus muscle advancement. MATERIALS AND METHODS: This retrospective study enrolled 25 patients. We evaluated scores for subjective snoring classification (Stanford scale) and questionnaire findings for esthetic results. RESULTS: Most people (96%) were satisfied with the esthetic improvement after surgery. The grade of subjective snoring classification (Stanford scale) improved from 8.68 (range 0-10) to 4.08 (range 0-10) after surgery. Twenty-four patients had an improved snoring grade. All patients reported a positive impact on their daily activity and self-confidence, and they were willing to recommend the same operation to someone with the same clinical problems. CONCLUSION: We conclude that hat-shaped mortised advancing genioplasty with genioglossus muscle advancement can relieve the symptoms of snoring for patients with hypoplastic chin or retrogenia. Patients were satisfied with the functional and esthetic results. LEVEL OF EVIDENCE IV: 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 .restrictio

Correlations between risk factors for atherosclerosis and histopathologic findings of radial artery

의학과/석사[한글] 요골동맥의 적합성(patency)은 요골측 전완부 피판(radial forearm flap)의 생존에 중요한 역할을 하며 내측 흉골동맥과 함께 관상동맥우회로술의 대치혈관(conduit)으로도 근래 널리 사용되고 있다. 요골동맥의 적합성은 관상동맥우회로술이나, 두경부 악성종양 제거 후 요골측 전완부 유리피판술의 성공여부에 매우 중요한 역할을 한다. 수술 전의 요골동맥의 적합성의 판정은 임상의 알렌검사(Allen test) 등에 의존하며, 실제로 요골동맥의 동맥경화 등과 같은 조직변화를 예측하기는 어렵다. 그러므로 수술 전에 요골동맥의 조직 변화의 예측은 수술의 예후 결정에 많은 도움을 줄 수 있을 것으로 생각된다. 본 연구에서는 동맥경화증의 위험인자와 요골동맥의 조직 소견을 비교하여 상관 관계를 조사하여 동맥경화증의 위험군에서 요골측 전완부 피판술이나 관상동맥우회로술 등을 시행함에 있어서 요골동맥이 혈관경이나 혈관이식의 공여부로서 사용되기에 충분한 안전성을 갖는지에 대해 평가하고자 한다. 실험은 38명의 환자에서 술전 이학적 검사를 통해서 동맥경화증 위험인자의 유무를 조사하였으며, 혈액 검사를 통해서 혈액내의 지질 수치 등을 조사하였고, 38개의 요골측 유리피판 거상 중에 채취한 혈관 절편을 대상으로 조직학적 검사를 실시하였다. 동맥경화증의 정도는 Kobayashi 등이 제시한 혈관의 내막(intima)과 중간층(media)의 두께의 비율인 R값에 의한 4단계로 나누어서 조사하였다. 동맥경화증의 정도를 알아보기 위해 측정한 R값(intima/media ratio)의 평균은 0.210±0.05로 나타났으며, grade I (R0.75)는 관찰되지 않았다. 동맥경화증의 위험인자 및 혈액 검사 치와 R값의 상관관계를 살펴본 결과, 환자들의 나이가 증가 할수록 R값은 증가하는 경향을 보였으나(상관계수= 0.3675, p<0.05) 나머지 위험인자와는 상관관계를 증명할 수는 없었다. 요골동맥의 동맥경화 조직 변화는 환자들의 나이가 가장 중요한 요인이며, 실제로 동맥경화증의 위험인자와 상관없이 모든 증례에서 뚜렷한 내관의 감소를 나타내지 않아 요골동맥은 유리 피판술이나 관상동맥우회로술에서 혈관의 공여부로서 유용하게 사용할 수 있을 것이라고 생각된다. [영문]The patency of radial artery plays an important role in survival of radial forearm fasciocutaneous free flap and artery conduit of coronary artery bypass graft procedure. Even though Allens’ test has been used for checking the patency of radial artery, the studies on the correlations between risk factors for atherosclerosis and histopathologic findings of radial arteries are rare until now. Therefore, we investigated the correlations between these two factors, and tried to estimate the feasibility of the radial artery in high-risk groups for artherosclerosis. The risk factors for atherosclerosis and lipid profiles were investigated in 38 patients by history taking, physical examinations and blood analysis. And 38 cases of segments of vessel were harvested during the elevation of flap. The degrees of medial sclerosis were estimated by R values (by Kobayashi and colleagues) that are the median value between thickness of intima and that of media. The measured mean R value was 0.210 + 0.05. And thirty one cases belonged to Grade I (R<0.25), 7 cases belong to Grade II (0.25<R< 0/5), none of cases belong to Grade III (0.5< R < 0.75) or Grade IV. Only age of the patients demonstrated a positive relationship with R values. (Correlation coefficient = 0.3675, p<0.05). In conclusions, the radial arteries in radial forearm flap demonstrate no significant narrow of the lumen due to medial or intimal thickening and radial arteries can be used in conduit of coronary artery bypass graft or forearm free flap regardless of risk factors of artherosclerosis.ope