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Journal of Plastic, Reconstructive &... Feb 2015The great auricular nerve (GAN) is often sacrificed during parotidectomy, rhytidectomy, and platysma flap operation. Transection of the nerve results in a wooden...
BACKGROUND
The great auricular nerve (GAN) is often sacrificed during parotidectomy, rhytidectomy, and platysma flap operation. Transection of the nerve results in a wooden numbness of preauricular region, pain, and neuroma. The aim of this study was to describe the branching patterns and distribution area of the GAN.
METHODS
Twenty-five embalmed, adult hemifacial Korean cadavers (16 males, nine females; mean age 62.5 years) were used in this study. The branching of the GAN was determined through careful dissection. The histological structure of the GAN was also examined by harvesting and sectioning specimens, and then viewing them with the aid of a light microscope.
RESULTS
The branching pattern of the anterior, posterior, deep, and superficial branches of the GAN could be classified into five types: type I (20%), where the deep branches arose from the anterior branch; type II (24%), where all branches originated at the same point; type III (28%), where the deep branch arose from the posterior branch; type IV (8%), where the superficial branches arose from the posterior branch; and type V (20%), where the anterior and posterior branches ran independently. A connection between the GAN and the facial nerve trunk was observed in all specimens, and a connection with the auriculotemporal nerve was observed in a few specimens. The total fascicular area of both regions decreased from proximal (1.42 mm2) to distal (0.60 mm2). There were 2.5 and 5 fascicles in the proximal and distal regions, respectively.
CONCLUSION
The results reported herein will help toward preservation of the GAN during surgery in the region of the parotid gland. Furthermore, the histologic findings suggest that the GAN would be a good donor site for nerve grafting.
Topics: Cadaver; Cervical Plexus; Ear, External; Facial Nerve; Female; Humans; Male; Mandibular Nerve; Microscopy; Middle Aged; Parotid Gland
PubMed: 25465135
DOI: 10.1016/j.bjps.2014.10.030 -
The Journal of Hand Surgery Jun 2023Ulnar wrist denervation has been a successful treatment for patients with ulnar-sided wrist pain. The purpose of this study was to characterize the articular branches of...
PURPOSE
Ulnar wrist denervation has been a successful treatment for patients with ulnar-sided wrist pain. The purpose of this study was to characterize the articular branches of the dorsal branch of the ulnar nerve (DBUN) and validate a technique for selective peripheral nerve blockade.
METHODS
In cadavers, we performed simulated local anesthetic injections using 0.5 mL of 0.5% methylene into the subcutaneous tissue at a point midway between the palpable borders of the pisiform and ulnar styloid. We then dissected the DBUN, characterized its articular branching pattern, and measured staining intensity of the DBUN and the ulnar nerve relative to a standard.
RESULTS
The DBUN branched from the ulnar nerve 7.0 ± 1.2 cm proximal to the ulnar styloid. Among 17 specimens, the DBUN provided an average of 1.2 (range, 0-2) ulnocarpal branches and 1.0 (range, 0-2) carpometacarpal articular branches. A simulated local anesthetic injection successfully stained 100% of the DBUN articular branches at or proximal to their takeoff. There was no staining of the proper ulnar nerves. In all specimens, the DBUN supplied at least one articular branch.
CONCLUSIONS
A point midway between the palpable border of the pisiform and ulnar styloid may be an effective location for selectively blocking the DBUN articular afferents.
CLINICAL RELEVANCE
In this study, we were able to identify a point halfway between the pisiform and ulnar styloid that has the potential to produce a selective peripheral nerve block of the portion of the DBUN that supplies articular fibers to the ulnocarpal joint and the fifth carpometacarpal joint. This technique may prove useful to surgeons treating ulnar-sided wrist pain.
Topics: Humans; Ulnar Nerve; Anesthetics, Local; Wrist; Arthralgia; Denervation; Cadaver
PubMed: 36966047
DOI: 10.1016/j.jhsa.2023.02.004 -
Journal of Cell Science Dec 2021Branches are critical for neuron function, generating the morphological complexity required for functional networks. They emerge from different, well-described,...
Branches are critical for neuron function, generating the morphological complexity required for functional networks. They emerge from different, well-described, cytoskeletal precursor structures that elongate to branches. While branches are thought to be maintained by shared cytoskeletal regulators, our data from mouse hippocampal neurons indicate that the precursor structures trigger alternative branch maintenance mechanisms with differing stabilities. Whereas branches originating from lamellipodia or growth cone splitting events collapse soon after formation, branches emerging from filopodia persist. Furthermore, compared to other developing neurites, axons stabilise all branches and preferentially initiate branches from filopodia. These differences explain the altered stability of branches we observe in neurons lacking the plasma membrane protein phospholipid phosphatase-related protein 3 (PLPPR3, also known as PRG2) and in neurons treated with netrin-1. Rather than altering branch stability directly, PLPPR3 and netrin-1 boost a 'filopodia branch programme' on axons, thereby indirectly initiating more long-lived branches. In summary, we propose that studies on branching should distinguish overall stabilising effects from effects on precursor types, ideally using multifactorial statistical models, as exemplified in this study.
Topics: Animals; Axons; Cells, Cultured; Growth Cones; Mice; Neurites; Neurons
PubMed: 34766183
DOI: 10.1242/jcs.258983 -
Neurology International Jan 2024(1) Background: Considering that the specialty literature supplies only general data about the variability of the cervical branch of the facial nerve, this study aimed...
(1) Background: Considering that the specialty literature supplies only general data about the variability of the cervical branch of the facial nerve, this study aimed to determine this branch's variation and individual peculiarities depending on the nerve branching pattern and anthropometric type of the head. (2) Methods: The study was conducted on 75 hemifaces of adult formalized cadavers. Ahead of anatomical dissection, each head was measured to establish the anthropometric type, according to Franco and colleagues. The branching patterns were then distributed according to the Davis classification. (3) Results: The number of cervical branches (CB) of the facial nerve varied from one to five branches, with the following rate: 1 CB (61.3%), 2 CB (28%), 3 CB (6.7%), 4 CB (2.7%), and 5 CB (1.3%). Seven branching patterns of the facial nerve were revealed: Type I in 18.7%, Type II in 14.7%, Type III in 20%, Type IV in 14.6%, Type V in 5.3%, Type VI in 18.7%, and Type NI in 8% (bizarre types). According to the branching pattern, the mean numbers of the cervical branches were as follows: Type I-1.6 ± 1.02; Type II-1.4 ± 0.50; Type III-1.4 ± 0.50; Type IV-1.4 ± 0.67; Type V-2.0 ± 1.41; Type VI-1.8 ± 1.12; and Type-NI-1.8 ± 0.75; = 0.599. According to the anthropometric type of the head, the mean number of CB in the mesocephalic type (MCT) was 1.5 ± 0.82, in the dolichocephalic type (DCT), 1.7 ± 0.87, and in the brachycephalic type, (BCT) 1.8 ± 1.04; = 0.668. (4) Conclusions: The cervical branch of the facial nerve varies depending on the facial nerve branching pattern and the anthropometric type of the head. The highest degree of variation was characteristic of BCT and Type V and the lowest, of MCT and Types II, III, and IV.
PubMed: 38251055
DOI: 10.3390/neurolint16010007 -
Clinical Anatomy (New York, N.Y.) Apr 2005Knowledge of the anatomy of the median nerve is important in surgery of the palmar aspect of the hand. The purpose of our study was to investigate the ramification...
Ramification pattern of the thenar branch of the median nerve entering the thenar fascia and the distribution of the terminal branches in the thenar musculature: Anatomic cadaver study in 144 hands.
Knowledge of the anatomy of the median nerve is important in surgery of the palmar aspect of the hand. The purpose of our study was to investigate the ramification pattern of the thenar branch before entering the thenar fascia and the distribution of the terminal branches in the thenar musculature. The observations were carried out on 144 hands of 74 dissecting room cadavers. According to the number of the thenar branches entering the thenar fascia we classified our specimens into four types. In 121 hands (84%, Group I) the thenar branch piercing the thenar fascia was a single trunk. In 19 hands (13.2%, Group II) two branches; in three (2.1%; Group III), three branches; and in one hand (0.7%; Group IV), four branches were identified entering the thenar fascia. Accessory thenar nerve was found in 8.3% of hands. The further division of each branch to its terminal branches was investigated in detail. Our results show that the more the number of thenar branches entering the thenar fascia, the less the terminal branching. Because more than one branch was seen in 16% of the specimens, meticulous dissection is required for preventing injury of the thenar branches before entering the thenar fascia.
Topics: Aged; Cadaver; Dissection; Fascia; Female; Humans; Male; Median Nerve; Middle Aged; Muscle, Skeletal; Thumb
PubMed: 15768414
DOI: 10.1002/ca.20067 -
The Journal of Knee Surgery Oct 2015The aim of the study was to gain an appreciation of the variation in the branching pattern and diameter of the genicular arteries arising directly from the popliteal...
The aim of the study was to gain an appreciation of the variation in the branching pattern and diameter of the genicular arteries arising directly from the popliteal artery (PA), namely, the superior medial genicular artery (SMGA), superior lateral genicular artery (SLGA), inferior medial genicular artery (IMGA), inferior lateral genicular artery (ILGA), and middle genicular artery (MGA). Twenty cadaveric knees aged between 62 and 92 years were dissected. A posterior midline vertical incision was used to gain access to the PA. The diameter of the PA, the sequence of branching, and subsequent diameter of genicular vessels and common trunks were recorded. PA average diameter was 7.9 mm. The SMGA (1.6-mm diameter) was the first branch in 45% and the second branch in 20%, and in seven limbs it arose from a common trunk with the SLGA. The SLGA was the second branch in 30% and the first branch in 25%, and it branched from a common trunk in 45%. The MGA (1.1-mm diameter) arose as the second branch in four knees and as the third branch in eight knees. It arose from a common trunk in eight knees, either with a superior genicular (three knees) or with an inferior genicular (five knees). The IMGA (1.5-mm diameter) was the third branch in 25%, the fourth branch in 35%, and the fifth branch in 15%. In five cases, it arose from a common trunk (25%). The ILGA (1.4-mm diameter) was the third branch in 15%, the fourth branch in 30%, and the fifth branch in 25%. It arose from a common trunk in six knees. These trunks also gave rise to the IMGA in all cases. There is extensive variation in the branching pattern and diameter of the genicular arteries differing from textbook descriptions. An awareness of vascular variation is imperative for preservation of the blood supply to the knee, which may promote recovery after anterior cruciate ligament reconstruction and popliteal aneurysm repair.
Topics: Anterior Cruciate Ligament; Cadaver; Dissection; Female; Humans; Knee Joint; Male; Popliteal Artery; Popliteal Vein; Sex Factors
PubMed: 25892007
DOI: 10.1055/s-0035-1549021 -
Skeletal Muscle Aug 2023The occurrence of hyperplasia, through myofibre splitting, remains a widely debated phenomenon. Structural alterations and fibre typing of skeletal muscle fibres, as...
BACKGROUND
The occurrence of hyperplasia, through myofibre splitting, remains a widely debated phenomenon. Structural alterations and fibre typing of skeletal muscle fibres, as seen during regeneration and in certain muscle diseases, can be challenging to interpret. Neuromuscular electrical stimulation can induce myofibre necrosis followed by changes in spatial and temporal cellular processes. Thirty days following electrical stimulation, remnants of regeneration can be seen in the myofibre and its basement membrane as the presence of small myofibres and encroachment of sarcolemma and basement membrane (suggestive of myofibre branching/splitting). The purpose of this study was to investigate myofibre branching and fibre type in a systematic manner in human skeletal muscle undergoing adult regenerative myogenesis.
METHODS
Electrical stimulation was used to induce myofibre necrosis to the vastus lateralis muscle of one leg in 5 young healthy males. Muscle tissue samples were collected from the stimulated leg 30 days later and from the control leg for comparison. Biopsies were sectioned and stained for dystrophin and laminin to label the sarcolemma and basement membrane, respectively, as well as ATPase, and antibodies against types I and II myosin, and embryonic and neonatal myosin. Myofibre branches were followed through 22 serial Sects. (264 μm). Single fibres and tissue blocks were examined by confocal and electron microscopy, respectively.
RESULTS
Regular branching of small myofibre segments was observed (median length 144 μm), most of which were observed to fuse further along the parent fibre. Central nuclei were frequently observed at the point of branching/fusion. The branch commonly presented with a more immature profile (nestin + , neonatal myosin + , disorganised myofilaments) than the parent myofibre, together suggesting fusion of the branch, rather than splitting. Of the 210 regenerating muscle fibres evaluated, 99.5% were type II fibres, indicating preferential damage to type II fibres with our protocol. Furthermore, these fibres demonstrated 7 different stages of "fibre-type" profiles.
CONCLUSIONS
By studying the regenerating tissue 30 days later with a range of microscopy techniques, we find that so-called myofibre branching or splitting is more likely to be fusion of myotubes and is therefore explained by incomplete regeneration after a necrosis-inducing event.
Topics: Male; Adult; Infant, Newborn; Humans; Muscle Fibers, Skeletal; Muscle, Skeletal; Regeneration; Myosins; Necrosis
PubMed: 37573332
DOI: 10.1186/s13395-023-00322-2 -
PLoS Computational Biology Mar 2016Branching is an important mechanism by which axons navigate to their targets during neural development. For instance, in the developing zebrafish retinotectal system,...
Branching is an important mechanism by which axons navigate to their targets during neural development. For instance, in the developing zebrafish retinotectal system, selective branching plays a critical role during both initial pathfinding and subsequent arborisation once the target zone has been reached. Here we show how quantitative methods can help extract new information from time-lapse imaging about the nature of the underlying branch dynamics. First, we introduce Dynamic Time Warping to this domain as a method for automatically matching branches between frames, replacing the effort required for manual matching. Second, we model branch dynamics as a birth-death process, i.e. a special case of a continuous-time Markov process. This reveals that the birth rate for branches from zebrafish retinotectal axons, as they navigate across the tectum, increased over time. We observed no significant change in the death rate for branches over this time period. However, blocking neuronal activity with TTX slightly increased the death rate, without a detectable change in the birth rate. Third, we show how the extraction of these rates allows computational simulations of branch dynamics whose statistics closely match the data. Together these results reveal new aspects of the biology of retinotectal pathfinding, and introduce computational techniques which are applicable to the study of axon branching more generally.
Topics: Animals; Computer Simulation; Connectome; Image Interpretation, Computer-Assisted; Models, Anatomic; Models, Neurological; Neurogenesis; Superior Colliculi; Time-Lapse Imaging; Zebrafish
PubMed: 26998842
DOI: 10.1371/journal.pcbi.1004813 -
Anatomy & Cell Biology Dec 2018Variations in the vascular anatomy of the carotid triangle have been reported in current scientific literature. The carotid arteries, being the major feeding arteries of...
Variations in the vascular anatomy of the carotid triangle have been reported in current scientific literature. The carotid arteries, being the major feeding arteries of the head and neck deserve special importance and protection from iatrogenic injury during radiological evaluations and surgical interventions. The present study was carried out over a period of 4 years from 2012-2016 to assess the variant anatomy of external carotid artery. The external carotid artery and its branches were dissected bilaterally in 40 formalin embalmed cadavers. The external carotid artery was traced from its origin to termination and variations in the branching pattern as well as the level of the carotid bifurcation were observed and analysed. A higher carotid bifurcation was observed in 25% cases. The linguofacial trunk was the commonest variation noted in the branching pattern seen in 20% cases. A single case of unilateral thyrolinguofacial trunk was also observed. The external carotid artery gave rise to accessory branches in 7.5% cases namely the superior laryngeal, accessory ascending pharyngeal and masseteric branches. A slender branch to the internal jugular vein was also observed in one case. These findings may provide further insight into the understanding of the vascular anatomy of the carotid triangle to the curious student, the discerning radiologist and the vigilant surgeon to avert complications and help improve overall treatment outcome.
PubMed: 30637155
DOI: 10.5115/acb.2018.51.4.225 -
Journal of Endovascular Therapy : An... Dec 2022The purpose of the study was to describe the design and implantation of a branched stent-graft during endovascular aortic repair incorporating double-cuff bidirectional...
PURPOSE
The purpose of the study was to describe the design and implantation of a branched stent-graft during endovascular aortic repair incorporating double-cuff bidirectional inner branch.
TECHNIQUE
A new double-cuff bidirectional antegrade and retrograde inner branched stent-graft with large diamond-shaped fenestration was designed for incorporation of a splenic artery. The inner cuffs of the branch were accessible using brachial and/or femoral access. The splenic artery was originating from an aortic segment with narrow inner aortic luminal diameter in a patient with extent IV thoracoabdominal aortic aneurysm with bilobed configuration. The retrograde, more distal inner cuff of the branch was extended into the splenic artery using a self-expandable bridging stent-graft from the femoral approach, whereas the antegrade, more proximal inner cuff of the branch was intentionally occluded using an endovascular plug. The recovery was uneventful and a computed tomography angiography 30 days postoperatively showed patency of all the target vessels without signs of endoleaks.
CONCLUSION
This is the first design of a double-cuff bidirectional inner branched stent-graft. The technique can potentially expand the applications of directional branches to patients with more difficult anatomy in the thoracoabdominal or aortic arch segments. Potential indications are patients with target arteries that are not ideally suited for caudally-oriented branches, patients with accessory vessels, or targets with early branch bifurcations.
CLINICAL IMPACT
This report describes the use of a branched endograft with a new double-cuff bidirectional branch that can potentially address many of the limitations of current BEVAR solutions, such as early bifurcations, double arteries with adjacent origins and arteries with less favorable trajectories for the traditional caudally-oriented branches.
PubMed: 36482664
DOI: 10.1177/15266028221139200