Anatomical variations of the external branch of the superior laryngeal nerve in relation to the inferior constrictor muscle: cadaveric dissection study

2012 ◽  
Vol 126 (9) ◽  
pp. 907-912 ◽  
Author(s):  
U Patnaik ◽  
A Nilakantan ◽  
T Shrivastava
Keyword(s):  
Superior Laryngeal Nerve ◽  
Anatomical Variations ◽  
Laryngeal Nerve ◽  
Rational Approach ◽  
Cadaveric Dissection ◽  
Constrictor Muscle ◽  
External Branch ◽  
Type 3

AbstractObjectives:To determine anatomical variations in the external branch of the superior laryngeal nerve in relation to the inferior constrictor muscle, and to propose a rational approach for the preservation of the nerve in thyroid surgery based on anatomical principles.Method:A cadaveric dissection study of the anatomy of the external branch of the superior laryngeal nerve in relation to the inferior constrictor muscle was conducted. Twenty-nine formalin-fixed cadavers of both sexes (age 50–70 years), with normal necks, were examined.Results:In relation to the Friedman classification, three anatomical variations of the external branch of the superior laryngeal nerve were found. Type 1 variation was found in 57.1 per cent of cases, type 2 in 26.8 per cent and type 3 in 16 per cent.Conclusion:The prevalence of type 3 variation of the external branch of the superior laryngeal nerve suggests that the nerve will not be encountered in a certain percentage of individuals as it lies under the cover of the inferior constrictor. Therefore, there is no justification for attempting to identify the nerve in all cases.

scholarly journals Extralaryngeal Terminal Division of the Inferior Laryngeal Nerve: Anatomical Classification by a Surgical Point of View

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Emin Gurleyik
Keyword(s):  
Anatomical Variation ◽  
Great Majority ◽  
Laryngeal Nerve ◽  
Point Of View ◽  
Entry Point ◽  
Inferior Laryngeal Nerve ◽  
Anatomical Classification ◽  
Type 3

Background. Complete anatomic knowledge including all variations of the inferior laryngeal nerve (ILN) is mandatory for thyroid surgeon. Extralaryngeal terminal division (ETD) of the ILN has significant importance for the safety of thyroidectomy.Material and Methods. Surgical dissection of 200 ILNs was performed on 100 cases. The presence of ETD of the nerve was determined intraoperatively. We propose by a surgical point of view a regional (segmental) classification of ETD of the ILN along its cervical course.Results. ETD has been observed in 54/200 nerves (27%). Great majority are bifurcated nerves (trifurcation 2%). Four types of ETD are classified. In type 1 (arterial; 46.3%), ETD has occurred near inferior thyroid artery (ITA). In type 2 (postarterial; 31.5%), division has been found on postarterial segment. In type 3 (prelaryngeal; 11%), division has been located very close to laryngeal entry point. In type 4 (prearterial; 11%), ETD has occurred before the nerve crossing the ITA.Conclusions. ETD of the ILN is a common anatomical variation. The bifurcation occurs in the ILN at various distances from laryngeal entry point. The classification increasing surgeons’ awareness may help to simplify identification and exposure of terminal branches. Preservation of both extralaryngeal terminal branches of the ILN has paramount importance for the safety of thyroid operations.

scholarly journals Anatomical landmarks of the external branch of the superior laryngeal nerve

2019 ◽  
Vol 12 (4) ◽  
pp. 161-177
Author(s):  
Viktor Y. Malyuga ◽  
Aleksandr A. Kuprin
Keyword(s):  
Thyroid Cartilage ◽  
Oblique Line ◽  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
Constrictor Muscle ◽  
External Branch ◽  
Close Proximity ◽  
Inferior Pharyngeal Constrictor ◽  
Line Type

Background. The external branch of the superior laryngeal nerve innervates a cricothyroid muscle, which provides tension in vocal cords and formation of high-frequency sounds. When the nerve is damaged during surgery, patients may notice hoarseness, inability to utter high pitched sounds, “rapid fatigue” of the voice, and dysphagia. According to literature, paresis of an external branch of the superior laryngeal nerve reaches up to 58% after thyroid surgery. Aim: to identify permanent landmarks and topographic variations of the external branch of the superior laryngeal nerve. Materials and methods. The study is based on the autopsy material (21 complexes organs of the neck) and on identification of variations of 40 external branches of the superior laryngeal nerve. We identified two permanent landmarks that are located at the minimum distance from nerve and we made metrical calculations relative to them: oblique line of thyroid cartilage and tendinous arch of the inferior pharyngeal constrictor muscle. Results. The piercing point of the nerve is always located at the inferior pharyngeal constrictor muscle without protruding beyond the oblique line of thyroid cartilage superiorly and tendinous arch of the inferior pharyngeal constrictor muscle anteriorly. The nerve had the parallel direction in 92.8% of cases (angel less than 30 degrees) relative to the oblique line and in 85.7% cases it was in close proximity to this line (at distance up to 4 mm). The proposed topographic classification of the location of the external branch of the superior laryngeal nerve is based on localization of the piercing point of the nerve relative to the length of the oblique line of thyroid cartilage and the risk of nerve damage. In 14.2% of cases, the piercing point was in the front third of the line (type I), and in 50% it was in the middle third of this line (type II). These variations of the external branch of the superior laryngeal nerve was in close proximity to the upper pole of the thyroid gland, which could have lead to its damage during surgery. In type III and IV (35.8%) – the piercing point in the muscle was located as far as possible from the upper pole of the thyroid gland and the greater part of the nerve was covered with the fibers of inferior pharyngeal constrictor muscle. Conclusion. We identified the main orienteers for the search and proposed anatomical classification of the location of the external branch on the superior laryngeal nerve.

scholarly journals Association between the Anatomy of the Mandibular Canal and Facial Types: A Cone-Beam Computed Tomography Analysis

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Rudyard dos Santos Oliveira ◽  
Arlete Maria Gomes Oliveira ◽  
José Luiz Cintra Junqueira ◽  
Francine Kühl Panzarella
Keyword(s):  
Anatomical Variations ◽  
Mandibular Canal ◽  
Root Tips ◽  
Morphological Variations ◽  
The Face ◽  
Facial Types ◽  
Type 3 ◽  
Facial Type

We evaluated the anatomical variations of the mandibular canal associated with various facial types, age, sex, and side of the face studied. We analyzed 348 hemimandibles in subjects without a history of trauma, lesions in the lower arch, or orthognathic or repair surgery in the posterior mandible. Facial type was determined using the VERT index. The canal path was classified as Type 1 (a large, single structure passing very close to the root tips); Type 2 (a canal passing closest to the mandibular base); and Type 3 (a canal present in the posterior mandibular region, with a lower canal running through the mandibular branch, reaching the anterior region). Bifid canals (type 3) were classified into four categories according to the course and number of mandibular canals. The brachyfacial and mesofacial types presented a Type 1 canal in 95.5% (n=166) of subjects, in dolichofacial types, 68.2% (n=45) presented a Type 2 canal, while in the mesofacial type, a lower prevalence of the bifid mandibular canal was observed (13.0%, n=23) than in the other facial types. The bifid canal showed significant association with facial type only (p<0.05), but no significant association was observed with the anterior loop type (p>0.05). Facial type is significantly associated with the path and morphological variations of the mandibular canal, independently of the side of the face studied, age, and sex.

scholarly journals Various patterns of the middle cerebral vein and preservation of venous drainage during the anterior transpetrosal approach

2016 ◽  
Vol 124 (2) ◽  
pp. 432-439 ◽  
Author(s):  
Shunsuke Shibao ◽  
Masahiro Toda ◽  
Maaya Orii ◽  
Hirokazu Fujiwara ◽  
Kazunari Yoshida
Keyword(s):  
Venous Drainage ◽  
Anatomical Variations ◽  
Cerebral Vein ◽  
Drainage Patterns ◽  
Anterior Transpetrosal Approach ◽  
Superficial Middle Cerebral Vein ◽  
Anterior Petrosectomy ◽  
Type 3

OBJECT The drainage of the superficial middle cerebral vein (SMCV) has previously been classified into 4 subtypes. Extradural procedures and dural incisions during the anterior transpetrosal approach (ATPA) may interrupt the route of drainage from the SMCV. In this study, the authors examined the relationship between anatomical variations in the SMCV and the corresponding surgical modifications to the ATPA that are necessary for venous preservation. METHODS This study included 48 patients treated via the ATPA in whom the SMCV was examined using 3D CT venography. The drainage patterns of the SMCV were classified into 3 types: cavernous or absent (Type 1), sphenobasal (Type 2), and sphenopetrosal (Type 3). Type 2 was subdivided into medial (Type 2a) and lateral (Type 2b), and Type 3 was subdivided into vein (Type 3a), vein and sinus (Type 3b), and sinus (Type 3c). The authors performed 3 ATPA modifications to preserve the SMCV: epidural anterior petrosectomy with subdural visualization of the sphenobasal vein (SBV), modification of the dural incision, and subdural anterior petrosectomy. Standard ATPA can be performed with Type 1, Type 2a, and Type 3a drainage. With Type 2b drainage, an epidural anterior petrosectomy with subdural SBV visualization is appropriate. The dural incision should be modified in Type 3b. With Type 3c, a subdural anterior petrosectomy is required. RESULTS The frequency of each type was 68.7% (33/48) in Type 1, 8.3% (4/48) in Type 2a, 4.2% (2/48) in Type 2b, 14.6% (7/48) in Type 3a, 2.1% (1/48) in Type 3b, and 2.1% (1/48) in Type 3c. No venous complications were found. CONCLUSIONS The authors propose an SMCV modified classification based on ATPA modifications required for venous preservation.

scholarly journals VIRIATION OF THE EXTERNAL BRANCH OF THE SUPERIOR LARYNGEAL NERVE

2019 ◽  
Vol 21 (1) ◽  
pp. 84-88
Author(s):  
V Y Malyuga ◽  
A A Kuprin
Keyword(s):  
Thyroid Gland ◽  
Thyroid Cartilage ◽  
Oblique Line ◽  
Superior Laryngeal Nerve ◽  
Laryngeal Nerve ◽  
Type I ◽  
Constrictor Muscle ◽  
Point Of Entry ◽  
External Branch ◽  
Inferior Pharyngeal Constrictor

Till now, there is no universal clinical classification about variations of the external branch of the superior laryngeal nerve despite the multiple classifications that was proposed. The aim of this research is identification and systematization of topographic types of the external branch of the superior laryngeal nerve. The study is based on the autopsy material (21 complexes organs of the neck) and on identification of variations of 40 external branches of the superior laryngeal nerve. We identify two permanent landmark that are located at the minimum distance from nerve and on which we made metrical calculations: oblique line of thyroid cartilage, tendinous arch of the inferior pharyngeal constrictor muscle. The “entry” point of the nerve is always located on the inferior pharyngeal constrictor muscle,and not protruding beyond the oblique line of thyroid cartilage superiorly and tendinous arch of the inferior pharyngeal constrictor muscle anteriorly. The proposed topographic classification of the location of the external branch of the superior laryngeal nerve is based on localization of point of pierced of the nerve relating to the length of the oblique line of thyroid cartilage. In 64.2% of cases, the external branch of the superior laryngeal nerve was in close proximity to the upper pole of the thyroid gland, which could lead to its damage during surgery (type I and II). In type III and IV (35.8%) - the point of "entry" in the muscle was located as far as possible from the upper pole of the thyroid gland, and most of the nerve was covered by the fibers of the inferior pharyngeal constrictor muscle.

Tracheal Agenesis

1992 ◽  
Vol 101 (7) ◽  
pp. 560-566 ◽  
Author(s):  
Peter J. Koltai ◽  
Robert Quiney
Keyword(s):  
Congenital Anomaly ◽  
Classification Scheme ◽  
Difficult Problem ◽  
Rational Approach ◽  
Tracheal Agenesis ◽  
Autopsy Specimens ◽  
Type 3 ◽  
Case Based

Tracheal agenesis is a catastrophic congenital anomaly that invariably results in death. Forty-seven cases have been previously reported in the literature. We add five additional cases, including two type 1 cases, two type 2 cases, and one type 3 case, based on Floyd's classification scheme. We describe the features of this unusual anomaly at the time of diagnosis. We discuss a rational approach to the management of this difficult problem on an emergent basis that allows for the maintenance of the infant's life until all of the implications of this fatal condition can be assessed. While we do not advocate reconstructive surgery for this anomaly, which has been universally fatal, we discuss the potential rearrangement of the anatomy, which may offer some hope in future cases. The concomitant congenital anomalies associated with these cases are reviewed, and autopsy specimens are presented for their anatomic interest.

FUNCTIONAL STATUS AND ADAPTIVE POTENTIAL IN FOREIGN STUDENTS WITH DIFFERENT TYPES OF VEGETATIVE REGULATION DURING TUITION

2020 ◽  
pp. 118-126
Author(s):  
A.M. Satarkulova
Keyword(s):  
Heart Rate ◽  
Foreign Students ◽  
Autonomic Regulation ◽  
The Body ◽  
Functional Changes ◽  
Different Types ◽  
Type 3 ◽  
Adaptive Abilities

The assessment and dynamic control over students’ status is a very important task. It allows timely detection of prenosological status prior to pathology and health maintenance in students. The objective of the paper is to assess the adaptive abilities of the body, to analyze changes in heart rate variability indicators in students with various types of autonomic regulation, to identify prenosological status and precursory pathological symptoms. Materials and Methods. The study enrolled 302 students from India, aged 21.54±1.43. Programming complex «Psychophysiologist» was used to register the main HRV parameters within 5 minutes. Health status was evaluated according to the index of functional changes and the scale of functional states. Results. N.I. Shlyk (2009) distinguished two groups of students with different types of autonomic regulation: type 1 (53 %) with moderate and type 2 (5 %) with marked characteristics of central regulation profile, type 3 (35 %) with moderate and type 4 (7 %) with marked characteristics of autonomous regulation profile. Main parameters of HRV and adaptation potential were defined for each student.All the parameters characterized functional and health status. Conclusions. It was shown that 82 % of trial subjects (type 1), 53 % (type 2), 94 % (type 3) and 95 % (type 4) demonstrated satisfactory adaptation and their physiological processes were at an optimal level. 18 % of students (type 1) demonstrated reduced adaptive abilities of the body. Moreover, they were under moderate stress. 47 % of subjects (type 2) were also under a significant stress, which was proven by excessively high SI, low SDNN and TP, and an increased index of functional changes. 5 % of students (type 4) revealed dysfunctional characteristics in the heart rhythm, peculiar to pathology. Keywords: foreign students, heart rate variability, types of autonomic regulation, adaptation potential, functional status. Оценка состояния студентов и динамический контроль за ним является важной задачей, поскольку позволяет своевременно выявлять у студентов донозологические состояния, предшествующие патологии, и способствовать сохранению здоровья. Цель. Оценка адаптивных возможностей организма, анализ изменений показателей вариабельности сердечного ритма у студентов с различными типами вегетативной регуляции, выявление донозологических состояний и ранних признаков патологии. Материалы и методы. В исследовании участвовало 302 студента в возрасте 21,54+1,43 года из Индии. Регистрировались основные параметры ВСР в течение 5 мин с использованием программно-аппаратного комплекса «Психофизиолог». Состояние и уровень здоровья оценивались по индексу функциональных изменений и шкале функциональных состояний. Результаты. По способу, предложенному Н.И. Шлык, выделены группы студентов с различными типами вегетативной регуляции: I (53 %) и II типы (5 %) – с умеренным и выраженным преобладанием центрального контура регуляции соответственно, III (35 %) и IV типы (7 %) – с умеренным и выраженным преобладанием автономного контура регуляции соответственно. У каждого из студентов определены основные параметры ВСР и адаптационного потенциала, характеризующие функциональное состояние и уровень здоровья. Выводы. Показано, что для 82 % обследуемых с I типом, 53 % со II типом, 94 % c III типом и 95 % с IV типом регуляции характерно состояние удовлетворительной адаптации, физиологические процессы сохраняются на оптимальном уровне. В группе студентов I типа у 18 % студентов адаптивные возможности организма снижены, выявлено состояние умеренного напряжения. У 47 % обследуемых II типа также зафиксировано состояние резко выраженного напряжения, индикатором которого является чрезмерно высокое значение SI, низкие величины SDNN и ТP, повышенное значение индекса функциональных изменений. В группе студентов с IV типом у 5 % учащихсяв регуляции ритма сердца выявлены дисфункциональные признаки, характерные для патологии. Ключевые слова: иностранные студенты, вариабельность сердечного ритма, типы вегетативной регуляции, адаптационный потенциал, функциональное состояние.

POLIOMYELITIS IN CANADIAN ESKIMOS: LABORATORY STUDIES. V. TYPE 1 AND TYPE 3 POLIOMYELITIS ANTIBODY LEVELS IN BAFFIN ISLAND ESKIMOS

1954 ◽  
Vol 32 (1) ◽  
pp. 119-125
Author(s):  
W. Wood ◽  
Eina M. Clark ◽  
F. T. Shimada ◽  
A. J. Rhodes
Keyword(s):  
Medical Records ◽  
Baffin Island ◽  
Tissue Cultures ◽  
Laboratory Studies ◽  
Poliomyelitis Virus ◽  
Antibody Titers ◽  
Antibody Levels ◽  
Type 3

Studies on the basic immunology of poliomyelitis in Canadian Eskimos have been continued. Some 87 sera collected from Eskimos at Pangnirtung, Baffin Island, have been examined for the presence of Type 1 and Type 3 poliomyelitis antibody by quantitative tests in tissue cultures. The same sera were previously examined for Type 2 antibody by quantitative tests in mice. The results of the three determinations are now presented together for comparison. These sera came from Eskimos aged 2 to 72 years of age. None of the Eskimos showed any evidence of paralysis. Examination of the medical records did not suggest that any paralytic disease had been present in this part of Baffin Island. Very few of the sera showed the presence of poliomyelitis antibody; thus, Type 1 antibody was demonstrated in the sera of 8%, Type 2 antibody in the sera of 9%, and Type 3 antibody in the sera of 14%. No significant number of Eskimos below the age of 45 years had acquired poliomyelitis antibody. The antibody titers mostly ranged between 10−1.0 and 10−2.0, and were significantly lower than the titers customarily found in recently paralyzed cases. These findings suggest that poliomyelitis infection occurred in Pangnirtung Eskimos many years before the date on which the samples were taken (1951). These results point to the worldwide prevalence of the three types of poliomyelitis virus.

Toward Personalized Treatment for Patients with Low von Willebrand Factor and Quantitative von Willebrand Disease

2021 ◽  
Vol 47 (02) ◽  
pp. 192-200
Author(s):  
James S. O'Donnell
Keyword(s):  
Von Willebrand Factor ◽  
Bleeding Risk ◽  
Von Willebrand Disease ◽  
Personalized Treatment ◽  
Treatment Plans ◽  
Type 3 ◽  
Von Willebrand ◽  
Willebrand Factor

AbstractThe biological mechanisms involved in the pathogenesis of type 2 and type 3 von Willebrand disease (VWD) have been studied extensively. In contrast, although accounting for the majority of VWD cases, the pathobiology underlying partial quantitative VWD has remained somewhat elusive. However, important insights have been attained following several recent cohort studies that have investigated mechanisms in patients with type 1 VWD and low von Willebrand factor (VWF), respectively. These studies have demonstrated that reduced plasma VWF levels may result from either (1) decreased VWF biosynthesis and/or secretion in endothelial cells and (2) pathological increased VWF clearance. In addition, it has become clear that some patients with only mild to moderate reductions in plasma VWF levels in the 30 to 50 IU/dL range may have significant bleeding phenotypes. Importantly in these low VWF patients, bleeding risk fails to correlate with plasma VWF levels and inheritance is typically independent of the VWF gene. Although plasma VWF levels may increase to > 50 IU/dL with progressive aging or pregnancy in these subjects, emerging data suggest that this apparent normalization in VWF levels does not necessarily equate to a complete correction in bleeding phenotype in patients with partial quantitative VWD. In this review, these recent advances in our understanding of quantitative VWD pathogenesis are discussed. Furthermore, the translational implications of these emerging findings are considered, particularly with respect to designing personalized treatment plans for VWD patients undergoing elective procedures.

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