Arterial anatomy of the ear

Imaging of the vascular distribution of the outer ear using optical coherence tomography angiography for highly accurate positioning of a hearable sensor

Novel hearable technology is securely and comfortably positioned within the ear canal minimizing inaccuracies caused by accessory movements during activities. Despite extensive research on hearable technologies within the outer ear, there is a lack of research in the field of vascular imaging and quantitative analysis in the outer ear in vivo, which is one of the crucial factors to select the appropriate sensor position. Therefore, in this paper, we introduced optical coherence tomography angiography (OCTA)-based qualitative and quantitative analyses to visualize the inner vasculature of the outer ear to acquire vascular maps for microvascular assessments in vivo. By generating maximum amplitude projection images from three-dimensional blood vascular volume, we identified variations of blood vessel signal caused by the different biological characteristics and curvature of the ear among individuals. The performance of micro-vascular mapping using the proposed method was validated through the comparison and analysis of individual vascular parameters using extracted 20 vascular-related variables. In addition, we extracted pulsatile blood flow signals, demonstrating its potential to provide photoplethysmographic signals and ear blood maps simultaneously. Therefore, our proposed OCTA-based method for ear vascular mapping successfully provides quantitative information about ear vasculature, which is potentially used for determining the position of system-on-chip sensors for health monitoring in hearable devices.

Effect of Tissue Pedicle Position on Postoperative Recovery From Severe Auricular Laceration

BACKGROUND

Postoperative recovery from severe auricular lacerations varies significantly. However, few studies have sought to clarify the risk factors associated with the prognosis of severe auricular lacerations, and little attention has been paid to the intraoperative management of severe auricular lacerations and early postoperative intervention. The purpose of this study was to analyze the risk factors that may affect the prognosis of severe auricular lacerations.

METHODS

Case data and imaging data of patients with severe auricular lacerations treated in our department between January 2018 and September 2022 were collected. A total of 90 patients (90 severe auricular lacerations) were included in the analysis and were divided into good group (68 cases) and poor group (22 cases) according to postoperative recovery, which was defined as poor postoperative recovery when postoperative auricular blood supply disorders required interventional treatment or second stage plastic surgery.

RESULTS

The percentage of ventral tissue pedicles in the poor recovery group was 77.3% ( P <0.001). The proportion of ventral tissue pedicle was significantly higher in the poor postoperative group than in the good postoperative group, and ventral tissue pedicle [odds ratio (OR)=12.22, P =0.002] was an independent risk factor for poor postoperative recovery from severe auricular laceration.

CONCLUSIONS

The prognosis of patients with severe auricular lacerations differs between the different tissue pedicle locations, and prophylactic treatment of patients with ventral tissue pedicles is beneficial. In addition, patients with ventral tissue pedicles should be informed in advance of their increased risk of surgical failure.

Ear ischemia induced by endovascular therapy for arteriovenous fistula of the sigmoid sinus: A case report

BACKGROUND

Arteriovenous fistula of the sigmoid sinus is an abnormal connection of arteries with the sigmoid sinus. Endovascular treatments of such lesions are considered safe and with low rates of complications.

CASE SUMMARY

A 62-year-old female patient underwent endovascular treatment of an arteriovenous fistula of the right sigmoid sinus on February 7, 2017, but her tinnitus was not cured. She was admitted to the Beijing Tiantan Hospital, Capital Medical University, on March 20, 2017, and her pre-operative diagnosis, by digital subtraction cerebral angiography, was arteriovenous fistula of the sigmoid sinus. She underwent endovascular embolization of the distal occipital artery and posterior auricular artery using Onyx-18. The arteriovenous fistula of the sigmoid sinus was cured, and her tinnitus disappeared, but ischemia of the upper 2/3 of the right auricle occurred without hearing loss. The patient received treatment to improve microcirculation, in addition to fluid supplementation, analgesia, and hyperbaric oxygen, and the swelling due to ischemia in the right auricle did not progress further. The patient reported no tinnitus , and the right auricle had returned to normal 3 years later.

CONCLUSION

Ischemic complications of vital organs should be considered when performing embolization procedures for arteriovenous fistulas of cerebral sinuses. Compensation of the organs should be evaluated before the operation, and the related treatment regimens should be planned.

The Conchal Vascular Foramen of the Posterior Auricular Artery: Application to Conchal Cartilage Grafting

The posterior auricular artery (PAA), a branch of the external carotid artery, gives rise to a conchal network formed by PAA perforators through the conchal floor of the auricle. However, this branch and its entrance (foramen) to the anterior concha, is rarely illustrated in the literature and has not been studied in detail. Therefore, we aimed to investigate the morphology of the perforating artery (PA) and its vascular foramen (VF). Ten sides from five formalin-fixed frozen Caucasian cadaveric heads were used. The number, diameter of the VF, diameter of the perforating artery (PA), shape of the VF (circular or oval), distance from the middle of the tragus and origin of the artery were documented. The number of VF ranged from 1 to 2; one was seen on 90% of the sides and two were seen on 10% of the sides. The VF was oval in 36% of the sides and circular in the remaining 64%. The mean diameter of the long and short axes of the VF, and PA was 2.0±1.4 mm, 1.3±0.9 mm, and 0.7±0.4 mm, respectively. Diameter of the PA was 1.0 mm or greater in 18% of the sides. The mean distance from the middle of the tragus to the VF was 10.7±2.6 mm. The perforating artery of the concha originated from the posterior auricular artery on all 11 sides.

Partial Ear Defects

Reconstruction of partial ear defects represents one of the most challenging areas within reconstructive surgery of the head and neck. Each case of auricular reconstruction is unique and warrants a systematic approach that accounts for defect size and location, the quality of the surrounding skin, patient preference, and operator experience. In this article, the authors outline different reconstructive approaches for defects of the upper-, middle-, and lower-third of the auricle. The relevant anatomy is discussed in detail. Successful outcomes in auricular reconstruction rely on the surgeon's careful analysis of the defect as well as knowledge of the different reconstructive options available.

[Earlobe reconstruction in one step by the Gavello's procedure: Surgical technique and a case report]

The earlobe because of its anatomical position is subject of defects secondary to multiple and varied etiologies. Although its functional role appears negligible, its aesthetic and social importance makes its reconstruction a delicate surgery because it must be discreet but also the simplest possible. Many methods have been described but some require several operating times. The aim of this article is to present a simple procedure with a bilobed flap based on a reliable vascularization and which requires only one operative time. We describe the technique through a clinical case and review the literature to discuss the other methods described.

Reevaluation of the arterial blood supply of the auricle

The anatomical basis for auricular flaps used in multiple aesthetic and reconstructive procedures is currently based on a random distribution of the underlying arterial network. However, recent findings reveal a systematic pattern as opposed to the present concepts. Therefore, we designed this study to assess the arterial vascular pattern of the auricle in order to provide reliable data about the vascular map required for surgical interventions. Sixteen human auricles from eight body donors (five females/three males, 84.33 ± 9.0 years) were investigated using the unique 'Spalteholz' method. After arterial injection of silicone, a complete transparency of the tissue was achieved and the auricular arteries and branches were visible. Qualitative and quantitative evaluation of the arterial vascular pattern was performed. The superior and the inferior anterior auricular artery provided the vascular supply to the helical rim, forming an arcade, i.e. helical rim arcade. On the superior third of the helical rim another arcade was confirmed between the superior anterior auricular artery and the posterior auricular artery (PAA), i.e. the helical arcade. The perforators of the PAA were identified lying in a vertical line 1 cm posterior to the tragus, supplying the concha, inferior crus, triangular fossa, antihelix and the earlobe. The results of this study confirmed the constant presence of the helical rim arcade (Zilinsky-Cotofana), consistent perforating branches of the PAA, and the helical arcade (Erdman), and will help and guide physicians performing auricular surgeries toward fast and simple procedures with optimal patient satisfaction.

Angiographic study of the superior laryngeal artery

The study goals were to demonstrate the superior laryngeal artery in detail with angiograms and to understand its vasculature three-dimensionally. Three fresh cadavers were totally injected with lead oxide-gelatin mixture. The larynx with the surrounding tissue was resected and radiographed stereoscopically with soft X ray system. We get informed consent from a person in question and the bereaved family. The superior laryngeal artery was divided into the ascending and descending branches. The ascending branch supplied the epiglottis chiefly from the ventral surface, and anastomosed with branches of the lingual artery. The descending branch supplied the vestibular and vocal folds, muscles of the larynx and mucosa over the muscles, and anastomosed with distal branches of the superior thyroid artery. Stereographic angiograms and macroscopic observation enabled us to understand vasculature of the superior laryngeal artery.