Laryngeal nerve "anastomoses".

Laryngeal nerves have been observed to communicate with each other and forma variety of patterns. These communications have been studied extensively and have been of particular interest as it may provide an additional form of innervation to the intrinsic laryngeal muscles. Variations noted in incidence may help explain the variable position of the vocal folds after vocal fold paralysis. This study aimed to examine the incidence of various neural communications and to determine their contribution to the innervation of the larynx. Fifty adult cadaveric en-bloc laryngeal specimens were studied. Three different types of communications were observed between internal and recurrent laryngeal nerves viz. (1) Galen's anastomosis (81%):in 13%, it was observed to supply the posterior cricoarytenoid muscle; (2) thyroarytenoid communication (9%): this was observed to supply the thyroarytenoid muscle in 2% of specimens and (3) arytenoid plexus (28%): in 6%, it supplied a branch to the transverse arytenoid muscle. The only communication between the external and recurrent laryngeal nerves was the communicating nerve (25%). In one left hemi-larynx, the internal laryngeal nerve formed a communication with the external laryngeal nerve, via a thyroid foramen. The neural communications that exist in the larynx have been thought to play a role in laryngeal innervation. The results of this study have shown varying incidences in neural communications. Contributions from these communications have also been noted to various intrinsic laryngeal muscles which may be a possible factor responsible for the variable position of the vocal folds in certain cases of vocal fold paralysis.

The Ansa Cervicalis in Fetuses / El Asa Cervical en Fetos

The formation of ansa cervicalis (AC) is somewhat complex with both its course and location along the common carotid artery and internal jugular vein (IJV) varying. The aim of the study was to document the anatomy, formation and variations of AC. Forty fetuses (gestational age: 15 to 28 weeks) were obtained from the Department of Clinical Anatomy, Westville Campus, UKZN. A detailed micro-dissection of the posterior triangle of the neck and AC were completed using standard micro-dissecting instruments. Results of the formation of AC, its relationship to IJV and variations were recorded. The superior root was identified as a long willowy nerve that branched from the hypoglossal nerve, descended on the carotid sheath, anterior to the common carotid artery and IJV in 70 % and posterior to IJV in 30 % of the specimens. The inferior root of AC originated from the ventral rami of C2-C3 in 26%; ventral ramus of C3 in 58% and ventral ramus of C2 in 16%. Variations: a) Formation: (i) Dual formation of AC: The Hypoglossal nerve formed separate loops with the ventral rami of C2 and C3 (3%); (ii) "W" shaped appearance of AC above the superior belly of omohyoid (1%); (iii) A "vago-cervical complex" 3%; b) Origin and course: The superior root of AC received a contribution from the hypoglossal nerve, a short distance later it formed a loop around the IJV to ascend to the ventral ramus of C2 as the inferior root. The precise understanding of the anatomy of AC together with variations may assist anesthetists and surgeons to accurately identify the vascular and neural relations during surgical procedures.

La formación del asa cervical (AC) compleja, tanto en su curso como en ubicación, pueden variar a lo largo de la arteria carótida común y de la vena yugular interna (VYI). El objetivo del estudio fue determinar la anatomía, formación y variaciones del AC en fetos humanos. Cuarenta fetos (edad gestacional: 15 a 28 semanas) fueron obtenidos desde el Departamento de Anatomía Clínica, Westville Campus, UKZN. En cada muestra se realizó una detallada microdisección del triángulo posterior del cuello y del AC utilizando instrumental de microdisección estándar. Fueron registrados los resultados de la formación del AC, su relación con VYI y sus variaciones. La raíz superior fue identificada como un nervio largo y delgado que se ramificaba desde el nervio hipogloso, descendía por la vaina carotídea, anterior a la a. carótida común y la VYI en el 70% de los casos, y posterior a la VYI el 30%. La raíz inferior del AC se originaba desde los ramos ventrales de C2-C3 en el 26% de los casos; desde el ramo ventral de C3 en el 58% y desde el ramo ventral de C2 en 16% de los casos. Se observaron variaciones de formación: (i) dual del AC: el nervio hipogloso formó asas separadas con los ramos ventrales de C2 y C3 (3%), (ii) forma aparente de "W" sobre el vientre superior del m. omohioideo (1%) y (iii) un "complejo vago-cervical" (3%), y variaciones de origen y curso: la raíz superior del AC recibió una contribución del nervio hipogloso, y a corta distancia formó un bucle alrededor de la VYI para ascender al ramo ventral de C2 como una raíz inferior. El conocimiento preciso de la anatomía del AC junto con variaciones pueden ayudar a identificar con precisión las relaciones vasculares y neuronales durante los procedimientos quirúrgicos a anestesistas y cirujanos.

The Sympathetic and Parasympathetic Contributions to the Cardiac Plexus: a Fetal Study / Contribuciones Simpáticas y Parasimpáticas al Plexo Cardíaco: Estudio Fetal

The cardiac plexus is formed by sympathetic nerves originating from the superior, middle, inferior cervical or cervicothoracic ganglia as well as from the first to the fifth thoracic ganglia. Furthermore, the vagus nerve and its counterpart, the recurrent laryngeal nerve supply the cardiac plexus with parasympathetic cardiac nerves. This investigation aimed to review and record the medial contributions of the cervical ganglia, first to fifth thoracic ganglia and medial contributions of the vagus and recurrent laryngeal nerves to the cardiac plexus. The study involved bilateral micro-dissection of forty cadaveric fetal specimens (n=80). The origins of sympathetic contributions to the cardiac plexus were described as either ganglionic, inter-ganglionic or from both the ganglion and the inter-ganglionic sympathetic chain. The number of cervical sympathetic ganglia varied from two to five in this study; the superior cervical ganglion was constant while the middle cervical, vertebral, inferior cervical or cervicothoracic ganglia were variable. The prevalence of cardiac nerves were as follows: superior cervical cardiac nerve (95%); middle cervical cardiac nerve (73%); vertebral cardiac nerve (41%); inferior cervical cardiac nerve (21%) and cervicothoracic cardiac nerve (24%). This investigation records the thoracic caudal limit of the thoracic sympathetic contributions to the cardiac plexus as the T5 ganglion. The findings of this study highlight the importance of understanding the medial sympathetic contributions and their variations to the cardiac plexus as this may assist surgeons during minimal access surgical procedures, sympathectomies, pericardiectomies and in the management of diseases like Raynaud's Phenomenon and angina pectoris.

El plexo cardíaco está formado por los nervios simpáticos procedentes de los ganglios cervicales superior, medio e inferior o cervicotorácico, así como los ganglios torácicos desde el primero al quinto. Por otra parte, el nervio vago y su contraparte, el nervio laríngeo recurrente suministra al plexo cardíaco nervios cardíacos parasimpático. Esta investigación tuvo como objetivo revisar y registrar las contribuciones mediales de los ganglios cervicales, ganglios torácicos del primero al quinto ganglios y contribuciones mediales de los nervios laríngeos recurrentes y vagos en el plexo cardíaco. Se realizó la micro-disección bilateral de cuarenta especímenes cadavéricos fetales (n = 80). Los orígenes de las contribuciones simpáticas hacia el plexo cardíaco se describen de forma independiente como ganglionar o inter-ganglionar, o desde ambos ganglios y la cadena simpática interganglionar. El número de ganglios simpáticos cervicales varió de dos a cinco; el ganglio cervical superior fue constante, mientras que los ganglios medio-cervical, vertebral, cervical inferior o cervicotorácico fueron variables. La prevalencia de los nervios cardíacos fueron: nervio cardíaco cervical superior (95%); nervio cardíaco cervical medio (73%); nervio cardiaco vertebral (41%); nervio cardíaco cervical inferior (21%) y nervio cardíaco cervicotorácico (24% ). La investigación registró el límite torácico caudal de las contribuciones torácicas simpáticos al plexo cardíaco como el ganglio T5. Los resultados de este estudio muestran la importancia de comprender las contribuciones simpáticas mediales y sus variaciones en el plexo cardíaco, ya que podrían ayudar a los cirujanos durante los procedimientos quirúrgicos mínimanente invasivos, simpatectomías, pericardiectomías y en el manejo de enfermedades como el fenómeno de Raynaud y la angina de pecho.

An anatomical study of the arterial supply to the soft palate / Estudio anatómico de la irrigación arterial del paladar blando

This study provides a detailed description of the arteries supplying the soft palate via: (i) ascending palatine; (ii) tonsillar; (iii) ascending pharyngeal; and (iv) lesser palatine arteries. Detailed dissections were performed on each side of thirty fetal and twenty adult head and neck specimens (n=100). This investigation documents the arteries terminating at the respective parts (superior, middle and inferior) of the soft palate and demonstrated that the majority of arteries terminated at the superior (83 percent and middle (63 percent) parts, whereas the inferior part (34 percent) was documented to receive the poorest arterial supply. The present study recognized anastomotic connections in 6 percent of fetal specimens i.e. (i) between the ascending palatine and lesser palatine arteries which terminated at the superior part of the soft palate in 4 percent of fetal cases, and (ii) between the ascending pharyngeal and recurrent pharyngeal arteries which terminated at the inferior part in 2 percent of fetal specimens. The position and relations of the soft palate arteries is of significance to minimize the risk of vascular disruption and myomucosal or mucosal flap failure during cleft palate repair and for the surgical correction of velopharyngeal insufficiency...

Este estudio proporciona una descripción detallada de las arterias que irrigan el paladar blando a través de las arterias: (i) palatina ascendente, (ii) tonsilar, (iii) faríngea ascendente, y (iv) palatinas menores. Se realizaron disecciones bilateralmente en 30 cabezas y cuellos de fetos y 20 de adultos (n = 100). Esta investigación documentó las arterias que terminaron en diferentes partes (superior, media e inferior) del paladar blando y demostró que la mayoría terminaba a nivel superior (83 por ciento) y medio (63 por ciento), mientras que la parte inferior (34 por ciento recibía un escaso suministro arterial. Se reconocieron conexiones anastomóticas en 6 por ciento de las muestras fetales, (i) entre las aa. palatinas ascendentes y las aa. palatinas menores, que terminaron en la parte superior del paladar blando en 4 por ciento de los casos fetales, y (ii) entre las aa. faríngea ascendente y faríngea recurrente, que terminaban en la parte inferior en un 2 por ciento de las muestras fetales. La posición y las relaciones de las arterias del paladar blando es relevante para minimizar el riesgo de interrupción vascular y falla de los colgajos miomucosos o mucosos, durante la reparación de paladar hendido o en la corrección quirúrgica de insuficiencia velofaríngea...

The lesser occipital nerve in fetuses / El nervio occipital menor en fetos

The lesser occipital nerve (LON) is an ascending superficial branch of the cervical plexus that has a variable origin either from the ventral ramus of the second cervical nerve or second and third cervical nerves and is purely sensory. Forty fetuses (right side: 40/80; left: 40/80) with gestational ages between 15 to 28 weeks were microdissected to document the anatomy of the LON. Results: a) Incidence and Morphometry: LON present in 100 percent specimens, with average length on the right and left sides of 23.59 +/- 2.32 mm and 23.45 +/- 2.27 mm, respectively; b) Course: In its ascent towards the occipital region, the LON was located on the splenius capitus muscle in 85 percent of specimens and in 15 percent of the specimens, it ascended vertically on the sternocleidomastoid muscle towards the ear, innervating its superior third; c) Branching pattern: LON displayed (i) single: 70 percent; (ii) duplicate: 26 percent and (iii) triplicate: 4 percent patterns; d) Variation in the course of LON was observed in 6 percent of the specimens. Knowledge of the anatomy and variations of the LON may assist in the understanding of cervicogenic headaches and may be of assistance to anesthetists performing regional anesthesia for surgical procedures in the neck.

El nervio occipital menor (NOM) es una rama ascendente superficial del plexo cervical que tiene un origen variable ya sea del ramo ventral del segundo nervio cervical o de los nervios cervicales segundo y tercero, y es solamente sensitivo. Cuarenta fetos (lado derecho: 40/80; izquierdo: 40/80), con edades gestacionales de 15 a 28 semanas fueron microdisecados para documentar la anatomía del NOM. a) Incidencia y morfometría: el NOM estuvo presente en el 100 por ciento de los especímenes, con una longitud media de los lados derecho e izquierdo de 23,59 +/- 2,32 mm y 23,45 +/- 2,27 mm, respectivamente; b) Curso: en su ascenso hacia la región occipital, el NOM se localiza en el músculo esplenio de la cabeza en el 85 por ciento de las muestras y en el 15 por ciento de las muestras, ascendió verticalmente sobre el músculo esternocleidomastoideo hacia el oído, inervando el tercio superior, c) Patrón de ramificación: el NOM se observa (i) individual: 70 por ciento, (ii) duplicado: 26 por ciento y (iii) triplicado: 4 por ciento de los patrones; d) Variación en el curso de NOM se observó en el 6 por ciento de las muestras. El conocimiento de la anatomía y las variaciones del NOM puede ayudar en la comprensión de los dolores de cabeza cervical y puede ser de ayuda a los anestesiólogos a realizar la anestesia regional para procedimientos quirúrgicos en el cuello.

Galen's "anastomosis" revisited.

This study aimed to examine the incidence and contribution to the innervation of the larynx from Galen's "Anastomosis" (GA), which is the direct connection between the dorsal branches of the internal laryngeal nerve (ILN) and the recurrent laryngeal nerve (RLN). Fifty adult laryngeal specimens were micro-dissected. The diameter of the ILN and RLN were measured immediately after each had given off their muscular branches to form GA. The incidence of GA was 81%. The average diameter of the ILN after giving off muscular branches to form GA was 1.28 mm (right) and 1.27 mm (left) while the average diameter of the RLN after giving off muscular branches to form GA was 0.65 mm (right) and 0.68 mm (left). The weighted mean incidence of GA (77.3%) calculated from a review of the literature concurred with the present finding of 81%. The ILN and RLN supplied the laryngeal musculature. According to the results obtained; it appears that the ILN may provide a greater contribution to the connection between the ILN and RLN as the morphometric contribution from the ILN was larger in comparison to the RLN. In addition, the authors propose a suitable term viz. the "communicating branch" as opposed to the commonly used misnomer GA to describe the connection between the dorsal branch of the RLN and the ILN, based on the definition that an "Anastomosis" refers to blood vessels and that a single connection exists between the dorsal branch of the RLN and ILN.

The incidence of the foramen thyroideum in the South African population / Incidencia del foramen tiroideo en la población de sudáfrica

The foramen thyroideum is described as an occasional opening existing in one or both laminae of the thyroid cartilage which may or may not contain a neurovascular component. Foramen thryoideum was first described in the literature by Segond in 1847. Some authors consider its existence a structural variation rather than an anomaly, with classical texts of anatomy providing little detail when describing this foramen. This study was undertaken to investigate the incidence and characteristics of the foramen thyroideum in the South African population. A total of 80 formalin fixed cadaveric laryngeal specimens (obtained from the Department of Clinical Anatomy, University of KwaZulu-Natal, South Africa) were dissected. Larynges were dissected with the aid of a Stemi DV 4 light microscope. The incidence, location, dimensions and contents of the foramen thyroideum were recorded. The horizontal and vertical extent of each foramen was measured with a digital caliper. Six of the 80 (7.5 percent) specimens examined had distinctly identifiable foramina. Five of the six cases (4 male, 1 female) displayed bilateral foramina (6.3 percent), with one case (1 female) of a unilateral foramen (1.3 percent). Of the larynges that had bilateral foramina, a single case presented with two foramina on the same (right) thyroid lamina. A total of twelve foramina were observed. Gender distribution of foramen thyroideum was: male: right 5, left 4; female: right 2, left 1. Preceding investigators of the foramen thyroideum have rightly indicated that awareness of its presence is of paramount importance in order to preserve the structures that traverse it and also to comprehensively treat or contain laryngeal cancer.

El foramen tiroideo se describe como una apertura ocasional existente en una o ambas láminas del cartílago tiroides, la cual puede o no contener un componente neurovascular. El foramen tiroideo fue descrito por primera vez en la literatura por Segond en 1847. Algunos autores consideran su existencia como una variación estructural y no una anomalía, los textos clásicos de anatomía proporcionan pocos detalles al describir este foramen. Este estudio se realizó para investigar la incidencia y características del foramen tiroideo en la población Sudafricana. Fueron disecados 80 especímenes cadavéricos de larínge fijados con formalina (obtenidos del Departamento de Anatomía Clínica de la Universidad de KwaZulu-Natal, Sudáfrica). Las laringes fueron disecadas con la ayuda de un microscopio de luz Stemi DV 4. La incidencia, localización, dimensiones y contenido del foramen tiroideo fueron registradas. La extensión horizontal y vertical de cada foramen se midieron con un caliper digital. Seis de los 80 (7,5 por ciento) especímenes examinados tenían foramen tiroideos claramente identificables. Cinco de los seis casos (cuatro hombres y una mujer) mostraron forámenes bilaterales (6,3 por ciento), y un caso (una mujer) foramen unilateral (1,3 por ciento). De las laringes que presentaron forámenes bilaterales, un solo caso presentó dos forámenes en la misma lámina del cartílago tiroides (derecha). La distribución por sexo del foramen tiroídeo en hombres fue 5 derechos y 4 izquierdos, mientras que en mujeres 2 derechos y 1 izquierdo. Los resultados indican que el conocimiento de la presencia del foramen tiroideo es de vital importancia para preservar las estructuras que lo atraviesan y también para el tratamiento de integral o contención del cáncer de laringe.

Atypical anastomosis of laryngeal nerves.

The larynx and its associated structures derive their chief source of innervation from the superior and recurrent laryngeal nerves. Surgery of the larynx requires a sound knowledge of the normal anatomy as well as variations that may be encountered in this region. We report the presence of rare communications between the right external and internal laryngeal nerves as well as between the right external and inferior laryngeal nerves via a thyroid foramen. In addition, we report on bilateral innervation of the respective ipsilateral aryepiglottic, transverse, and oblique arytenoid muscles by the internal laryngeal nerve, which is contrary to the classical descriptions of this nerve. The anatomic features are described and clinical implications are highlighted.

Cervico-thoracic ganglion: its clinical implications.

Lesions of the cervicothoracic ganglion (CTG) result in interruption of sympathetic fibers to the head, neck, upper limb, and thoracic viscera. The accurate understanding of the anatomy of the CTG is relevant to sympathectomy procedures that may be prescribed in cases where conventional intervention has failed. This study documents the incidence and distribution of the CTG to avoid potential complications such as Horner's syndrome and cardiac arrhythmias. This study utilized 48 cadavers, in which a total of 89 sympathetic chains were dissected. The inferior cervical ganglion (ICG) and the first thoracic ganglion was fused in 75 cases (84.3%) to form the CTG. It was present bilaterally in 48 of these specimens (65.3%). Three different shapes of CTG were differentiated, viz. spindle, dumbbell, and an inverted "L" shape. The dumbbell and inverted "L" shapes demonstrated a definite "waist" (i.e., a macroscopically visible union of the ICG and T1 components of the CTG). Rami from the CTG was distributed to the brachial plexus, the subclavian and vertebral arteries, the brachiocephalic trunk, and the cardiac plexus. This study demonstrates a high incidence of a double cardiac sympathetic nerve arising from CTG. It is therefore imperative that in the technique of sympathectomy, for intractable anginal pain, the surgeon excises both these rami but does not destroy the ganglion itself. The ever-improving technology in endoscopic surgery has made investigations into the nuances of the anatomy of the sympathetic chain essential.

The surgical anatomy of the parotid fascia.

UNLABELLED: Currently, there are no reports in the literature of the parotid fascia suggesting that this structure is crucial to the identification of the facial nerve trunk (FNT). Traditional surgical and anatomical descriptions of this fascia report it as a collection of connective tissue large enough to be described by the unaided eye. This study was performed to investigate the composition and limit of the fascia surrounding the parotid gland. An appreciation of these on safe and effective parotid surgery was also considered. HISTO-ANATOMICAL STUDY: Microsurgical step-by-step dissection was performed on 18 adult cadavers (n=36) to define the composition, arrangement, and attachment of the parotid fascia. Samples were subjected to the Masson Trichrome Technique (1990). CLINICAL STUDY: A total of 18 patients presented for parotidectomy. Eight patients had a pleomorphic adenoma and ten had lympho-epithelial disease of the parotid gland. Boundaries of parotid fascia were posteriorly-mastoid process, anteriorly--ramus of mandible, superiorly--cartilage of external acoustic meatus, and inferiorly-imaginary line joining tip of mastoid process to ramus of mandible. These landmarks formed a quadrangular space. HISTO-ANATOMICAL STUDY (N=36): Parotid fascia formed a fibrous meshwork over the gland. In the upper two-thirds, fascia was thick and strong; in the lower one-third, fascia was thin. Soft tissue arrangement (from superficial to deep): dermis, subcutaneous fat, superficial cervical fascia, deep cervical fascia. CLINICAL STUDY (N=18): The technique described was applied consistently in all patients. Mean time for localization of FNT was 11 min (range 7-18 min). In two patients (both with an underlying inflammatory disorder of the parotid gland), a transient facial nerve palsy developed postoperatively. In both patients, this settled within 7 weeks of operation. The true surgical potential of the parotid fascia during parotidectomy has been reported.

Anatomical variations of the second thoracic ganglion.

In recent years the second thoracic ganglion has gained anatomical significance as an important conduit for sympathetic innervation of the upper extremity. Thoracoscopic excision of the second thoracic ganglion is now widely recognized as affording the most effective treatment option for palmar hyperhidrosis. This study recorded the incidence, location and associated additional neural connections of the second thoracic ganglion. Bilateral dissection of 20 adult cadavers was undertaken, and all neural connections of the second thoracic ganglion were recorded. Nineteen cadavers (95%) demonstrated additional neural connections between the first thoracic ventral ramus and second intercostal nerve. These were classified as either type A (47.5%) or type B (45%) using the intrathoracic ramus (nerve of Kuntz) between the second intercostal nerve and the ventral ramus of the first thoracic nerve as a basis on both right and left sides. The second thoracic ganglion was commonly located (92.5%) in the second intercostal space at the level of the intervertebral disc between the second and third thoracic vertebrae. Fused ganglia between the second thoracic and first thoracic (5%) and stellate (5%) ganglia were noted. These findings should assist the operating surgeon with a clear knowledge of the anatomy of the second thoracic ganglion during thoracoscopic sympathectomy with a view to improving the success rate for upper limb sympathectomy.

Anatomical basis for a successful upper limb sympathectomy in the thoracoscopic era.

In this clinico-anatomical study, factors potentially responsible for unsuccessful upper limb sympathectomy (ULS) by the thoracoscopic route were evaluated. This study comprised two subsets: 1) in the clinical subset, 25 patients (n = 50 sides) underwent bilateral second thoracic ganglionectomy for palmar hyperhidrosis, and factors predisposing to unsuccessful ULS were identified; and 2) in the anatomical subset, the neural connections of the first and second intercostal spaces were bilaterally dissected in 22 adult cadavers (22 right, 21 left; n = 43 sides). Alternate neural pathways (ANP) were noted in 9 of 50 sides in the 25 clinical cases (18%). In three asthenic patients (5 sides), fascia overlying the longus colli muscle mimicked the sympathetic chain. The right superior intercostal vein (SIV) was located anterior to the second thoracic ganglion in 6 of 50 sides (12%) and predisposed to troublesome bleeding in 2 of 50 cases; the SIV was posterior to the ganglion in 19 of 50 sides (38%), posing no technical problem. On the left, the SIV was noted outside the field of dissection in all but one case. A successful outcome to sympathectomy was noted in all 25 patients. A spectrum of sympathetic contributions to the first thoracic ventral ramus for the first intercostal space was noted in 37 of 43 anatomical cases (86%). These were categorized according to the arrangements of the intrathoracic ramus between the second intercostal nerve and the first thoracic ventral ramus. The cervicothoracic ganglion (37/43 cases; 86%) and an independent inferior cervical ganglion (6/43 cases; 14%) were always located above the second rib. The second thoracic ganglion was consistently located in the second intercostal space. This study demonstrates that ANPs have little clinical significance when a second thoracic ganglionectomy is undertaken. Technical failures may be avoided if the surgeon is mindful of anatomical variations at surgery.

The anatomical rationale for an upper limb sympathetic blockade: preliminary report.

Stellate ganglion blockade (SGB) has long been considered pivotal in the diagnosis, determination of prognosis and management of chronic regional pain syndrome (CRPS) by sympathectomy. To date a variety of SGB techniques have been described. An inaccurate SGB may mislead clinicians and deny patients a potentially beneficial procedure. In order to obtain a predictable and readily reproducible blockade of the upper limb, a modified anterior technique was evaluated. This modified sympathetic block was performed in 10 adult cadavers (n=19 sides). Toluidine blue solution (10 ml) was injected and, following median sternotomy, the extent of spread of dye was evaluated. In one cadaver a dual block using both the modified and the standard techniques was performed. Proximal spread to the seventh cervical vertebra was noted in all blocks; distal spread extended to the neck of the third rib (n=3), neck of the fourth rib 7 (n=15) and neck of the seventh rib (n=1). Medial spread was greater than lateral spread and extended to the vertebral bodies (vagus nerve was also stained) while lateral spread in all cases "blocked" lower roots of the brachial plexus and was consistently noted beyond the usual location of the nerve of Kuntz. This modified technique demonstrated that the lower cervical ganglia and proximal thoracic sympathetic trunk were consistently stained. It should be noted that the spread was sufficiently lateral to block the nerve of Kuntz. The pitfalls of this technique aside, we suggest that this technique be reserved for therapeutic purposes, particularly when sympathectomy is not possible.

Thoracoscopy: a new era for surgical anatomy.

In this new era of minimal access surgery, advances in optics and illumination have established thoracoscopic sympathectomy as a pre-eminent procedure, including a safe and efficient technique for upper limb sympathectomy. The success of thoracoscopy will doubtless ensure that a greater number of these procedures will be carried out and will put some of the daunting technical challenges posed by traditional open surgical procedures to rest. The thoracoscopic era affords the surgical anatomist a new challenge: to move the teaching of living anatomy to a higher level.

The sympathetic contributions to the cardiac plexus.

Cardiac sympathetic denervation for intractable angina pectoris in patients unsuitable for conventional revascularization is currently gaining popularity since this procedure may be performed via minimally invasive surgery. A thorough understanding of cardiac innervation and its variations is crucial to successfully effect cardiac denervation. This study aimed to demonstrate the cervical and thoracic sympathetic contributions to the cardiac plexus. The cervical and thoracic sympathetic trunks in 21 fetuses and eight adults were micro-dissected bilaterally and documented ( n=58 sides). The superior cervical cardiac ramus originated from the superior cervical ganglion (present in all specimens) in 53% of cases. The middle cervical ganglion (incidence 81%) gave rise to the middle cervical cardiac ramus in 88% of cases. The cervico-thoracic ganglion (incidence 85%) gave the cervico-thoracic cardiac ramus in 84%. In the thoracic region, four cardiac rami arose from the T2-T6 segment of the thoracic sympathetic trunk. All cervical and thoracic cardiac rami were traced consistently to the deep cardiac plexus. Khogali et al.'s (1999) success of limited T2-T4 sympathectomy in relieving pain at rest of patients with intractable angina pectoris appears to indicate that a significant afferent pain pathway from the heart is selectively interrupted. The variability in pattern of the cervical ganglia, cardiac rami and cervical contributions to the cardiac plexus does not appear to affect the outcome of limited sympathectomy. The complexity of cardiac pain pathways is not fully understood. The study is continuing and attempts to contribute to defining these cardiac neuronal pathways.

A thoracoscopic view of the nerve of Kuntz.

The nerve of Kuntz and alternate neural pathways (ANPs) have long been considered crucial for upper limb sympathetic supply. However, at thoracoscopy, these structures are neither consistently identified nor searched for. This is probably reflective of the effectiveness of an isolated second thoracic ganglionectomy for upper limb sympathectomy. We present the case of a 19-year-old male who underwent a second thoracic ganglionectomy for palmar hyperhidrosis. On the left side, approximately 2.5 cm lateral to the typically located sympathetic chain, a filamentous structure (one-quarter the diameter of the sympathetic chain), identified as the nerve of Kuntz, was noted coursing across the neck of the second rib.

Paraganglioma and adrenal pheochromocytoma presenting simultaneously in an elderly female. Case report and review of the literature.

Paragangliomas are chromaffin tissue tumors arising in an extra-adrenal location. It is quite rare to find a paraganglioma concurrently with a pheochromocytoma. We report a patient who underwent resection of a retroperitoneal mass that was characterized pathologically as a malignant paraganglioma. An incidental finding was a microscopic pheochromocytoma in the ipsilateral adrenal gland.

Thoracic splanchnic nerves: implications for splanchnic denervation.

Splanchnic neurectomy is of value in the management of chronic abdominal pain. It is postulated that the inconsistent results of splanchnicectomies may be due to anatomical variations in the pattern of splanchnic nerves. The advent of minimally invasive and video-assisted surgery has rekindled interest in the frequency of variations of the splanchnic nerves. The aims of this study were to investigate the incidence, origin and pattern of the splanchnic nerves in order to establish a predictable pattern of splanchnic neural anatomy that may be of surgical relevance. Six adult and 14 fetal cadavers were dissected (n = 38). The origin of the splanchnic nerve was bilaterally asymmetrical in all cases. The greater splanchnic nerve (GSN) was always present, whereas the lesser splanchnic nerve (LSN) and least splanchnic nerve (ISN) were inconsistent (LSN, 35 of 38 sides (92%); LSN, 21 of 38 sides (55%). The splanchnic nerves were observed most frequently over the following ranges: GSN, T6-9: 28 of 38 sides (73%); LSN, when present, T10-11: (10 of 35 sides (29%); and ISN, T11-12: 3 of 21 sides (14%). The number of ganglionic roots of the GSN varied between 3 and 10 (widest T4-11; narrowest, T5-7). Intermediate splanchnic ganglia, when present, were observed only on the GSN main trunk with an incidence of 6 of 10 sides (60%) in the adult and 11 of 28 sides (39%) in the fetus. The higher incidence of the origin of GSN above T5 has clinical implications, given the widely discussed technique of undertaking splanchnicectomy from the T5 ganglion distally. This approach overlooks important nerve contributions and thereby may compromise clinical outcome. In the light of these variations, a reappraisal of current surgical techniques used in thoracoscopic splanchnicectomy is warranted.

Thoracic origin of a sympathetic supply to the upper limb: the 'nerve of Kuntz' revisited.

An understanding of the origin of the sympathetic innervation of the upper limb is important in surgical sympathectomy procedures. An inconstant intrathoracic ramus which joined the 2nd intercostal nerve to the ventral ramus of the 1st thoracic nerve, proximal to the point where the latter gave a large branch to the brachial plexus, has become known as the 'nerve of Kuntz' (Kuntz, 1927). Subsequently a variety of sympathetic interneuronal connections down to the 5th intercostal space were reported and also described as the nerve of Kuntz. The aim of this study was to determine: (1) the incidence, location and course of the nerve of Kuntz; (2) the relationship of the nerve of Kuntz to the 2nd thoracic ganglion; (3) the variations of the nerve of Kuntz in the absence of a stellate ganglion; (4) to compare the original intrathoracic ramus with sympathetic variations at other intercostal levels; and (5) to devise an appropriate anatomical classification of the nerves of Kuntz. Bilateral microdissection of the sympathetic chain and somatic nerves of the upper 5 intercostal spaces was undertaken in 32 fetuses (gestational age, 18 wk to full term) and 18 adult cadavers. The total sample size comprised 99 sides. Sympathetic contributions to the first thoracic nerve were found in 60 of 99 sides (left 32, right 28). Of these, 46 were confined to the 1st intercostal space only. The nerve of Kuntz (the original intrathoracic ramus) of the 1st intercostal space had a demonstrable sympathetic connection in 34 cases, and an absence of macroscopic sympathetic connections in 12. In the remaining intercostal spaces, intrathoracic rami uniting intercostal nerves were not observed. Additional sympathetic contributions (exclusive of rami communicantes) were noted between ganglia, interganglionic segments and intercostal nerves as additional rami communicantes. The eponym nerve of Kuntz should be restricted to descriptions of the intrathoracic ramus of the 1st intercostal space. Any of these variant sympathetic pathways may be responsible for the recurrence of symptoms after sympathectomy surgery.