Localization of the superior laryngeal nerve during carotid endarterectomy

Knowledge of the topographic anatomy is essential to prevent iatrogenic damage of the superior laryngeal nerve (SLN) in carotid endarterectomy (CEA). The purpose of this study was to analyze the anatomic relationship between the SLN and carotid arteries in order to prevent iatrogenic nerve injury. Anatomic dissections similar to CEA were performed bilaterally in 50 fresh human adult cadavers. The topography of the SLN was analyzed regarding its relationship with the carotid arteries. Furthermore, the distance between the external branch of the SLN and the point of bifurcation of the common carotid artery (dCAB) was analyzed regarding effects of gender, ethnicity, individual stature and side of the neck. The SLN was always located adjacent and posterior to the carotid arteries.The dCAB ranged from 20.3 mm below the point of bifurcation of the common carotid artery to 50.9 mm above this level (average 10.3 mm above). Most dissections (75%) showed the external branch of the SLN emerging from behind the carotid artery above the arterial bifurcation; in only 10% of cases did this nerve emerge from the artery below that anatomic reference. Based on Student's t-test, there were no significant differences in the dCAB between genders ( P=0.237), ethnicities ( P=0.410) and sides of the neck ( P=0.872). Moreover, tall stature was not significantly correlated with a shorter dCAB (linear regression: R(2)=0.009, P=0.357). We conclude that most SLNs were located above the carotid artery bifurcation, but anatomic variations occurred in 25% of the dissections. The dCAB was unaffected by gender, ethnicity, individual stature and side of the neck.     

眶上裂区临床应用解剖研究进展

眶上裂区是眼眶与颅中窝沟通的重要通道,动眼神经、滑车神经、展神经、三叉神经第一支（ 眼神经）、 眼上静脉、眼下静脉等诸多重要神经、血管从中穿行,并且与视神经、颈内动脉、海绵窦等结构关系密切。眶上 裂区解剖对于颅底手术至关重要,手术时如损伤眶上裂区的神经、血管结构将导致严重的并发症。现就眶上裂区 的大体、显微及内镜临床应用解剖作简要综述。     

Anatomical and developmental aspects of iatrogenic injury to the right recurrent laryngeal nerve in surgical resections of substernal goiter

Thyroid surgery is the primary treatment for substernal goiters, and iatrogenic injury to the recurrent laryngeal nerve (RNL) is always a risk. The literature suggests that iatrogenic lesions of the RNL post resection of substernal goiter are not equally distributed, being more frequent on the right recurrent laryngeal nerve (R-RLN) in comparison to the left recurrent laryngeal nerve (L-RLN). The relative paucity of basic anatomical and clinical reportages on R-RLN iatrogenic injuries and on the developmental factors that may help explain its higher incidence justifies this study's undertaking. Here we compare incidence of right versus left iatrogenic injuries to the RLN in surgical resections of substernal goiters and discuss the anatomical and embryological factors involved. This report is part of a larger retrospective observational cohort study of 239 patients surgically treated for substernal goiter in the Gaffrée and Guinle University Hospital, Rio de Janeiro, from 2006 to 2018. From 239 patients, 13 presented with iatrogenic RLN injury, one patient presented bilateral lesion, totalling 15 iatrogenic lesions. Our analysis showed that the R-RLN seems to be anatomically more vulnerable to injury due to the embryological underpinnings addressed in this review, R-RLN = 64.29% (n = 9) and L-RLN = 35.71% (n = 5). Pathological factors like malignancy and size of the mass are relevant issues to be considered. The knowledge of anatomical landmarks and embryological development of the thyroid and associated structures can improve our understanding and teaching of surgical anatomy, thus helping prevent and reduce the number of iatrogenic injuries on right RLNs.     

Anatomic variations in the course of the hypoglossal nerve: A case report

To achieve a successful surgical anatomy a detailed knowledge of regional anatomy and anatomical variations is an important fundamental. The extra cranial hypoglossal nerve has a well described course as it traverses the neck, and is frequently identified during neck dissection. This serves a guide to the surgeon of such atypical variations in anatomy to avoid injury to important structures during dissection. We are presenting a case report which demonstrates the extra cranial variation of Hypoglossal nerve.     

The role of immunophilin ligands in nerve regeneration

Tacrolimus (FK506) is a widely used immunosuppressant in organ transplantation. However, it also has neurotrophic activity that occurs independently of its immunosuppressive effects. Other neurotrophic immunophilin ligands that do not exhibit immunosuppression have subsequently been developed and studied in various models of nerve injury. This article reviews the literature on the use of tacrolimus and other immunophilin ligands in peripheral nerve, cranial nerve and spinal cord injuries. The most convincing evidence of enhanced nerve regeneration is seen with systemic administration of tacrolimus in peripheral nerve injury, although clinical use is limited due to its immunosuppressive side effects. Local tacrolimus delivery to the site of nerve repair in peripheral and cranial nerve injury is less effective but requires further investigation. Tacrolimus can enhance outcomes in nerve allograft reconstruction and accelerates reinnervation of complex functional allograft transplants. Other non-immunosuppressive immunophilins ligands such as V-10367 and FK1706 demonstrate enhanced neuroregeneration in the peripheral nervous system and CNS. Mixed results are found in the application of immunophilin ligands to treat spinal cord injury. Immunophilin ligands have great potential in the treatment of nerve injury, but further preclinical studies are necessary to permit translation into clinical trials.     

An anatomic‐based approach to the iatrogenic spinal accessory nerve injury in the posterior cervical triangle: How to avoid and treat it

Iatrogenic injury of the spinal accessory nerve (SAN) is a significant reducible risk with any invasive procedure involving the posterior cervical triangle. Most commonly associated with cervical lymph node biopsy, it affects 3–6% of patients and serves as a major cause of avoidable medical malpractice litigation. Medical malpractice cases not only affect the primary surgeon but also may include the repairing surgeon through a shift of blame. For this reason, we discuss the strategies all clinicians may utilize in approaching iatrogenic SAN injuries. By taking basic precautionary measures based on simple application of anatomy in the management of these patients, clinicians may protect themselves from needless malpractice litigation. A thorough knowledge of the anatomy and application in preventative strategies may provide guidance for clinicians in reducing the incidence of iatrogenic injuries, providing effective postinjury management, and ensuring the salvaging surgeon is not at fault if litigation is pursued. Clin. Anat. 28:761–766, 2015. © 2015 Wiley Periodicals, Inc.     

颈动脉分叉区域的神经血管解剖及其对颈动脉内膜剥脱术的临床意义

目的　通过对尸体标本的颈动脉分叉区域内的神经、血管进行解剖研究,为安全有效地开展颈动脉内膜剥脱术提供形态学依据及解剖学基础。 方法 选取20例（40侧）无明确心、脑血管疾患的尸体解剖标本（男11例、女9例）,采取颈动脉内膜剥脱术式入路对颈动脉分叉区域内的神经、血管进行解剖研究,明确血管和神经的形态学及结构特点。 结果 颈总动脉分叉部形态可分为Ⅰ、Ⅱ、Ⅲ型,分别占比为10%、52.5%、37.5%。分叉位置以甲状软骨为界,左侧颈总动脉分叉部高度在其上缘以上、平上缘和上缘以下的占比分别为55%、37.5%、7.5%;相较之下右侧分别为62.5%、27.5%、10%。男性颈总、颈内、颈外动脉内径均大于女性（P<0.05）;男性颈动脉分叉角度大于女性（P<0.05 ）。双侧颈总、颈内、颈外动脉内径相比无统计学意义（P>0.0 5）;左侧颈动脉分叉角度大于右侧（P<0.05）。 结论　通过对颈动脉分叉区域内的神经、血管进行解剖研究,对颈动脉内膜剥脱术术中血管与神经的保护具有重要的临床意义。     

Distal biceps femoris avulsions: Associated injuries and neurological sequelae

BackgroundThe aim of this study was to describe associated injuries in cases of distal biceps femoris avulsions (DBFA) as well as the incidence of neurological injury and radiographic abnormalities of the common peroneal nerve (CPN).MethodsA retrospective chart review was conducted of patients presenting to our office or trauma center with DBFA injuries. Demographic data was obtained as well as mechanism of injury. Assessment of concomitant injuries and presence of neurologic injury was completed via chart review and magnetic resonance imaging (MRI) review. The CPN was evaluated for signs of displacement or neuritis.ResultsSixteen patients were identified (mean age-at-injury 28.6 years, 87.5% male) with DBFA. Three patients (18.8%) sustained their injuries secondary to high energy trauma while 13 (81.3%) had injuries secondary to lower energy trauma. Nine patients (56.3%) initially presented with CPN palsy. All patients presenting with CPN palsy of any kind were found to have a displaced CPN on MRI and no patient with a normal nerve course had a CPN palsy.ConclusionsThis case series demonstrates a strong association between DBFA and CPN palsy as well as multi-ligamentous knee injury (MLKI). These injuries have a higher rate of CPN palsy than that typically reported for MLKI. Furthermore, these findings suggest that CPN displacement on MRI may be a clinically significant indicator of nerve injury.LOE: IV.     

Injury to the lateral cutaneous nerve of forearm after venous cannulation: a case report and literature review

Venepuncture may be associated with nerve injuries and is commonly performed at the median cubital vein (MCV). Injuries to the superficial radial nerve at the wrist and to the median nerve, anterior and posterior interosseus nerves and medial and lateral cutaneous nerves (LCN) of the forearm at the cubital fossa have been reported. The LCN is a sensory branch of the musculocutaneous nerve and the position of the nerve in relation to the MCV is variable within the cubital fossa. The LCN supplies sensory innervation to the C6 dermatome corresponding to an area of skin overlying the radial border of the forearm. We report the case of a 30-year-old right-handed woman who presented with loss of sensation in the left forearm after donating blood at a transfusion centre. This was due to an injury of the LCN. After 3, 18 and 36 months of follow-up, the sensory deficit had only improved minimally. The lack of recovery of the sensation after 36 months indicates a permanent nerve injury such as neurotmesis rather than neurapraxia of the LCN. A thorough knowledge of the clinical anatomy of the MCV and the LCN, which is highlighted, is essential in preventing venepuncture-associated nerve injury.     

Choline acetyltransferase and calcitonin gene-related peptide immunoreactivity in motoneurons after different types of nerve injury

Summary This study examined changes in choline acetyltransferase and calcitonin gene-related peptide immunoreactivity in hypoglossal motoneurons of rats at 1, 3, 7, 20 and 50 days after three types of nerve injury: crush, transection and resection. Peripheral reinnervation was assayed by retrograde labelling of the motoneurons after injections of the exogenous protein, horseradish peroxidase, into the tongue. Maximal reduction in choline acetyltransferase immunostaining occurred at seven days after nerve damage and the amount of the decrease was related to the nature of the injury. The recovery of choline acetyltransferase to normal levels was related to the timing of reinnervation after nerve crush, but not after transection or resection injuries. In contrast to these findings, a rapid increase in calcitonin gene-related peptide immunoreactivity preceded the decrease in choline acetyltransferase levels. A striking increase in calcitonin gene-related peptide immunoreactivity was observed at one day postoperative and was maximal at three days postoperatively for all injuries. Later changes in calcitonin gene-related peptide levels were dependent on the type of injury. Increased calcitonin gene-related peptide staining persisted to 20 days after nerve crush. After nerve transection or resection, calcitonin gene-related peptide immunoreactivity decreased to basal levels at seven days postoperatively. This declination was followed by a second rise in calcitonin gene-related peptide immunolabeling at 20 days for nerve transection or at 50 days after resection. Nearly complete reinnervation was established by 20 days after nerve crush. At 50 days after transection, less than half the number of normally-labelled neurons contained horseradish peroxidase. At this time only 1% of those whose axons had been resected were labelled. These observations suggest that different mechanisms regulate the responses of choline acetyltransferase and calcitonin gene-related peptide to nerve injury. The present results indicate that choline acetyltransferase levels in motoneurons can not be used to predict either the likelihood of or the timing of reinnervation after nerve transection or resection. However, our results strengthen the premise that an increase of calcitonin gene-related peptide immunoreactivity serves as a reliable index for predicting nerve regeneration/reinnervation after cranial nerve injury.     

Biomechanical Characterization of Internal Layer Subfailure in Blunt Arterial Injury

Blunt carotid artery injuries occur in 0.3% of blunt injured patients and may lead to devastating neurological consequences. However, arterial mechanics leading to internal layer subfailure have not been quantified. Twenty-two human carotid artery segments and 18 porcine thoracic aorta segments were opened to expose the intimal side and longitudinally distracted to failure. Porcine aortas were a geometrically accurate model of human carotid arteries. Internal layer subfailures were identified using videography and correlated with mechanical data. Ninety-three percent (93%) of vessels demonstrated subfailure prior to catastrophic failure. All subfailures occurred on the intimal surface. Initial subfailure occurred at 79% of the stress and 85% of the strain to catastrophic failure in younger porcine specimens, compared to 44% and 60%, respectively, in older human specimens. In most cases, multiple subfailures occurred prior to catastrophic failure. Due to limitations in human specimen quality (age, prior storage), young and fresh porcine aorta specimens are likely a more accurate model of clinical blunt carotid artery injuries. Present results indicate that vessels are acutely capable of maintaining physiologic function following initial subfailure. Delayed symptomatology commonly associated with blunt arterial injuries is explained by this mechanics-based and experimentally quantified onset of subcatastrophic failure.     

经单鼻孔蝶窦入路垂体瘤切除术并发症的防治

目的探讨单鼻孔经蝶入路显微手术治疗垂体瘤的并发症及其防治。方法对60例垂体瘤患者采用单鼻孔经蝶入路显微手术治疗,为预防及减少并发症的发生,术前选好适应证,术中精细操作,术后及时妥善处理并发症。结果60例垂体瘤手术均顺利,出血不多,并发症少,没有发生视力恶化、颈内动脉及其分支损伤、颅神经损伤、颅内感染、长期脑脊液漏等严重或永久性并发症。本组共发生各种类型的并发症15例,其中出现一过性尿崩症5例（8．3％）,短暂脑脊液漏2例（3．3％）,视觉障碍2例（3．3％）,垂体功能低下2例（3．3％）,低钠血症4例（6．6％）,经积极治疗后均在3～8天内恢复。结论单鼻孔经蝶入路显微镜下切除垂体瘤并发症的发生与手术操作有关,熟悉局部解剖及良好的手术技巧可降低并发症的发生。术后并发症经积极合理的治疗能获得痊愈。     

The Accessory Nerve: A Comprehensive Review of its Anatomy,Development, Variations,Landmarks and Clinical Considerations

Introduction: The eleventh cranial nerve, the accessory nerve, has a complex and unique anatomy and has been the subject of much debate. Herein, we review the morphology, embryology, surgical anatomy, and clinical manifestations of the accessory nerve. Included in this review, we mention variant anatomy, molecular development, histology, and imaging of the accessory nerve. Conclusions: The accessory nerve continues to be a topic of much discussion regarding its exact function and in particular to its cranial roots. Recently, various surgical procedures have been devised that repurpose the accessory nerve (e.g., lengthening procedures, contralateral neurotization procedures). Currently, we continue to learn and have much to learn about this lower cranial nerve. Anat Rec, 302:620–629, 2019. © 2018 Wiley Periodicals, Inc.     

眶上裂区及其穿经结构的薄层冠状断层解剖学

目的：探讨眶上裂区及其穿经结构的薄层冠状断层解剖,为临床眶上裂区疾病的影像诊断提供形态学依据。方法：采用火棉胶切片技术对5例(10侧)成人眶上裂区标本进行连续薄层冠状断层解剖学观察。结果：眶上裂被Zinn腱环分为外侧区、中央区和内侧区,内有第Ⅲ、Ⅳ、Ⅴ_1、Ⅵ对脑神经及其分支和眼上静脉通过,未见眼下静脉。视神经由颅内的横椭圆形逐渐变为眶内的圆形;眼动脉在视神经管颅口、中部和眶口处分别位于视神经的内下方、正下方和外下方。结论：冠状断层对于眶上裂区及其穿经结构显示效果良好,应作为该区影像诊断的基本层面。火棉胶包埋结合滑动式切片机薄层连续切片技术是研究眶上裂区断层解剖学的一种简便适用、定位准确的方法。     

Changes in neuropeptide expression in the trigeminal ganglion following inferior alveolar nerve section in the ferret

Changes in neuropeptide expression in afferent nerve fibres may play a role in the persistent sensory abnormalities that can be experienced following trigeminal nerve injuries. We have therefore studied changes in the expression of the neuropeptides substance P, calcitonin gene-related peptide, enkephalin, galanin, neuropeptide Y and vasoactive intestinal polypeptide in the trigeminal ganglion following peripheral nerve injury. In anaesthetised adult female ferrets, the left inferior alveolar nerve was sectioned and recovery allowed for three days, three weeks or 12 weeks prior to perfusion-fixation. During a second procedure, one week prior to perfusion, the inferior alveolar nerve was exposed and an injection made central to the injury site using a mixture of 4 % Fluorogold and 4 % isolectin B4 conjugated to horseradish peroxidase to identify cell bodies with axons in the inferior alveolar nerve and cells with unmyelinated axons within this population, respectively. Control animals received tracer injection alone. After harvesting the tissue, sagittal sections were taken from both the right and left ganglia and immunohistochemical staining was used to reveal the presence of peptides and isolectin B4-horseradish peroxidase tracer. Within the Fluorogold-labelled population, cell counts revealed a significant reduction in the proportion of substance P-containing cells at three days (P = 0.0025), three weeks (P = 0.0094) and three months (P = 0.0149) after nerve section, and a significant reduction in the proportion of calcitonin gene-related peptide-containing cells at three days (P = 0.0003) and three weeks (P = 0.007). No significant changes were seen in the expression of the other peptides, or at other time periods. A significant reduction in the number of isolectin B4-horseradish peroxidase-positive cells (with unmyelinated axons) was seen at three days (P = 0.0025), three weeks (P = 0.0074) and three months after the injury (P = 0.0133). These results demonstrate a significant reduction in the expression of some neuropeptides in the early stages after inferior alveolar nerve section. Some of the results differ markedly from those reported previously in other systems, and may be related to the specific nerve studied, species variations or differences between spinal and trigeminal nerves.     

带蒂额肌帽状腱膜颅骨外板复合瓣修复颅前窝缺损的应用解剖

目的 为颅前窝组织缺损一次性修复重建提供研究资料。方法 选择22例国人较新鲜的尸体，经双侧颈总动脉用红色乳胶灌注，进行双侧眶上动脉和滑车上动脉解剖。结果 双侧眶上动脉与滑车上动脉在额部有100％的吻合，并见眶上动脉可达顶骨。二动脉亦与其他颅顶的动脉有吻合。结论 额肌、帽状腱膜、颅骨外板有恒定的血管，血供良好，取其复合组织瓣后，不损其美观，是一个值得推荐的复合组织瓣。     

Understanding racial variation in the use of carotid endarterectomy: the role of aversion to surgery.

Previous studies indicate that African-American patients undergo carotid endarterectomy at one fourth the rate of white patients. This study was undertaken to determine if differences in aversion to carotid endarterectomy might account for some of the racial difference in utilization of this procedure. A sample of 185 African-American and white patients was selected from a cohort of patients hospitalized for stroke or transient ischemic attack at four Veterans Affairs medical centers. Of these patients, 115 (62%) were able to be contacted by telephone and 95 (83%) agreed to be interviewed. The interview included assessments of functional status, patient preferences for their current health status, and risk aversion to a hypothetical carotid endarterectomy. Patients from both racial groups were similar in age, marital status, level of education, and comorbid medical illnesses. All respondents were male. Functional status for both groups was high and not statistically different. There were no significant racial differences in patients'' perceptions of their current health state. However, African-American patients expressed more aversion to the hypothetical surgery than whites. The median excess risk of death accepted to avoid surgery was 20% for African Americans versus 2.5% for whites. These results indicate that racial differences in the utilization of carotid endarterectomy may be due in part to differences in patients'' levels of aversion to this surgery.     

Alternative approaches for regional ulnar nerve blockade: a cadaveric study

Wrist blockade is a safe and effective alternative to general anesthesia in surgery of hand injuries. With regard to the ulnar nerve, the volar approach is used, where the needle passes through or medial to the flexor carpi ulnaris tendon; however, the ulnar artery is at risk because the needle may accidentally penetrate it, causing profuse bleeding. Alternatively, the wrist may be approached medially, the ulnar approach, and the needle tip placed posterior to the flexor carpi ulnaris tendon. To determine which of these methods may be preferable for avoiding ulnar artery injury, needles were inserted into the wrist area of cadaver hands (n = 57) using the volar and ulnar approaches; detailed dissection of the region around the inserted needles was subsequently carried out. The position of the ulnar nerve relative to the ulnar artery and injury to the artery was documented. Damage to the ulnar artery using the volar approach was 36.8% (21/57 cases) compared to no (0%) injury observed using the ulnar approach. At the level of the wrist crease just proximal to the pisiform bone, the ulnar nerve was medial to the artery in 92.9% (53/57) of cases, medial and posterior in 5.3% (3/57), and anterior to the artery in 1.8% (1/57) of cases. This study suggests that in cases where ulnar artery pulsation is not reliable, the ulnar approach may be preferable for ulnar nerve blockade due to an increased incidence of ulnar artery penetration with the volar approach.     

Carotid thrombosis due to intraoral trauma. An unusual complication of a common childhood accident.

The cases of a child and an adolescent in whom internal-carotid-artery thrombosis followed non-penetrating trauma to the paratonsillar area from objects held in the mouth are reported, and are discussed together with 10 similar cases collected from the literature. Although the incidence of this complication of an accident almost unique to childhood is unknown, 2 out of 15 children in a consecutive series with acute hemiplegia had a history of such trauma. This suggests that specific inquiry concerning such injuries should be made in any child with an acute, focal neurologic lesion. Physicians seeing patients with paratonsillar injuries should be aware that neurologic complications may ensue. As a rule, there is a period of up to twenty-four hours from the time of injury to the onset of neurologic symptoms; this may cause confusion with an intracranial hematoma in patients with a history of prior or associated head injuries. The diagnosis of internal-carotid-artery occlusion can be proved clinically only by angiography, which should be performed before therapy is undertaken. One third of the children with internal-carotid-artery occlusion after intraoral trauma died; the constant pathological finding was extension of the thrombus distally into the major intracranial arteries, with massive infarction of the hemisphere. A theory of the pathogenesis of occlusion of the internal carotid artery after nonpenetrating trauma is presented. A plan of therapy based on this hypothesis is considered.