The superior thyroid artery origin pattern: a systematic review with meta-analysis.

PURPOSE: The current systematic review with meta-analysis aimed to investigate the pooled prevalence of the superior thyroid artery (STA) pattern of origin (distinct or fused-common origin with adjacent arteries in the form of a common trunk). The standard and uncommon variants were also studied, considering the STA's exact surface of origin and the relationship with the upper border of the thyroid cartilage (TC, reference point), considering the laterality effect. Thus, the STA topographical anatomy was considered. METHODS: An evidence-based systematic review with meta-analysis was performed according to the PRISMA 2020 guidelines. A literature search was conducted in four online databases using specific keywords, the pooled prevalence was calculated using statistical analysis in the R programming language, and multiple subgroup analyses were performed. RESULTS: The most common distinct origin of the STA was from the external carotid artery (ECA) (56.94% pooled prevalence, 95%CI: 50.89-62.89), and the rarest one was from the internal carotid artery (ICA) (< 0.01%, 95%CI: 0.00-0.00). Common trunks were also investigated, with the thyrolingual trunk emanating from the ECA estimated at 0.61% (95%CI: 0.21-1.14), representing the most common. Subgroup analysis based on the nationality, type of study, and sample size, as well as a comparison between left and right sides and males and females, were investigated. CONCLUSIONS: The most common STA origin was estimated as the ECA, the medial surface of origin, and above the TC upper border. Adequate knowledge of STA origin is paramount for surgeons, especially during thyroidectomy, not to cause iatrogenic injury to the external branch of the superior laryngeal nerve.

A scarce combination of arterial variants: an occipital artery originating from the internal carotid artery associated with a linguofacial trunk.

The occipital artery (OA) typically originates from the external carotid artery (ECA). Variations of the ECA has been well described in the current literature, while the OA is a relatively stable vessel, and its variations are uncommon. In the current case report, an aberrant OA has been found coexisting with a linguofacial trunk (LFT) on the right hemineck of a 51-year-old male patient. The OA was identified originating from the cervical internal carotid artery (ICA) at the level of the second cervical vertebra (C2). On the ECA, the lingual and facial arteries were emanating in common, as LFT. The left hemineck of the patient was free of variations. The current coexistence of arterial variants has been reported only once previously; therefore, the current case corresponds to the second case in the English literature. The aberrant OA origin from the ICA has been estimated with a pooled prevalence of 0.37%, while the origin at the C2 level and from the anterior surface of the ICA corresponds to a very rare variation. Additionally, the LFT is one of the most common trunk that can be found on the ECA. Interventional radiologists and surgeons must be aware of common and uncommon variation to avoid iatrogenic lesion.

Congenital external carotid-internal carotid artery anastomosis: a report of three cases and literature review.

PURPOSE: Congenital external carotid-internal carotid artery (EC-ICA) anastomosis is a cervical arterial variation that was initially reported, based on anatomic dissection, from Japan in 2000. The purpose of this report is to show the characteristic radiological findings of this extremely rare cervical arterial variation. METHODS: We analyzed nine cases, including six previously reported cases and three cases that we recently experienced. Three of the six previously reported cases were from Japan, and the remaining three cases were from Korea. MR angiography (4), CT angiography (2), catheter angiography (2) and autopsy (1) were used as diagnostic modalities. RESULTS: The study population included eight men and one woman. Anastomosis was seen on the left side in seven cases and the right side in two cases, and it was located at the level of the C1/2-C2/3 intervertebral space. In all cases, ECA was larger than the ICA at the level of their origins. In four cases, the ICA was extremely small in caliber. In one case, the ICA may have been occluded postnatally, and its configuration was similar to that of the nonbifurcating cervical carotid artery (CCA). With the exception of this occluded case, the carotid bifurcation and EC-ICA anastomosis formed a large arterial ring in all cases. CONCLUSION: EC-ICA anastomosis can be regarded as a variant of the nonbifurcating CCA because if the most proximal segment of the small ICA is occluded, nonbifurcating CCA may form. EC-ICA anastomosis is located between the C1/2-C2/3 intervertebral space and may be formed by the remnants of the proatlantal artery I.

Simple Things Are Not Simple: Pulsatile Tinnitus due to Tortuous Occipital Artery.

BACKGROUND: Pulsatile tinnitus is often a chronic and debilitating condition and normally has a vascular origin. We describe a case of pulsatile tinnitus due to an aberrant branch of the external carotid artery (ECA), which has not been reported previously. METHOD: A 67-year-old female with chronic unilateral pulsatile tinnitus, which could be controlled completely with direct pressure on a small tortuous superficial branch behind her left ear. This was confirmed with doppler to be an unusually tortuous occipital branch of the ECA. Under local anesthesia, this vessel was identified with intraoperative doppler and ligated. RESULT: Complete resolution of tinnitus immediately, with consistent results 3 months postoperatively. CONCLUSIONS: Pulsatile tinnitus due to aberrances in the occipital ECA branch is rare, and in this case, was successfully treated with minor surgery.

Ascending pharyngeal artery-posterior inferior cerebellar artery anastomosis via the jugular foramen: a case report and literature review.

The posterior inferior cerebellar artery (PICA) rarely arises from the cavernous segment of the internal carotid artery (ICA) and is called persistent trigeminal artery variant. The PICA also can arise from the cervical segment of the ICA, and it enters the posterior fossa via the hypoglossal canal, where it is called persistent hypoglossal artery variant. Using magnetic resonance angiography (MRA), we diagnosed a 79-year-old man with a PICA arising from the ascending pharyngeal artery and passing through the medial side of the jugular foremen pars vascularis. Only six cases of this variation have been reported previously in the English language literature. To identify this variation on MRA, the careful observation of source images is useful. Recognizing this variation is important in order to avoid ischemic cerebellar complications during neck surgery and endovascular therapy.

Separate arch origin of the left external carotid artery with common trunk giving rise to the left internal carotid artery and left subclavian artery.

We present a case of a 3-year-old boy with tetralogy of Fallot having the direct origin of the left external carotid artery from the aorta with a common trunk giving rise to the left internal carotid artery and left subclavian artery, in a right-sided aortic arch. We also highlight the potential implications in management.

Case report of unique anastomosis between facial and inferior alveolar arteries.

PURPOSE: Understanding anatomical variations of the facial artery and its branches is important for dental and medical practitioners. METHODS: Routine cadaveric dissection of the head and neck was performed to demonstrate the origin and branches of the facial artery. RESULTS: Facial artery emerged from a common linguofacial trunk off the external carotid artery. On the face, the facial artery first gave off a pre-masseteric branch. Immediately after, an aberrant artery emerged from the facial artery that coursed along the ramus of the mandible, which upon further dissection and examination was found to anastomose with inferior alveolar artery within the ramus of the mandible. CONCLUSIONS: We report a unique anastomosis between facial and inferior alveolar arteries, vessels that have not been previously shown to communicate. This case report may provide useful information for oral and maxillofacial surgeons as well as dentists performing inferior alveolar nerve blocks.

Origin variations of the superior thyroid, lingual, and facial arteries: a computed tomography angiography study.

PURPOSE: To determine the anatomical variations and morphology of the external carotid artery (ECA) and its anterior branches. METHODS: Using computed tomography angiography (CTA), the origin, internal diameter, and surface laterality emergence of the superior thyroid (STA), lingual (LA), and facial (FA) arteries were evaluated retrospectively evaluated and classified. The bifurcation level of the common carotid artery (CCA) in relation to the cervical vertebrae and disc was also determined. RESULTS: A total of 76 CTA were included in the study. STA originated from the carotid bifurcation (CB) (type I), CCA (type II) and ECA (type III) in 20.4 (31/152), 17.1 (26/152) and 50.7% (77/152) cases, respectively. Also 10.5% (16/152) arose from a shared trunk with LA as a thyrolingual trunk (TLT) (type IVa), and absent in 1.3% (2/152). LA originated in the CB in only one case. A linguofacial trunk (LFT) was present in 14.5% (22/152). Mean diameters of STA, LA and FA were 1.70, 1.95 and 2.45 mm, respectively. Meanwhile, surface laterality were predominately from anteromedial, medial, and anterior, respectively. CB was mainly on C3 or C3-C4 (55.9% of cases). CONCLUSIONS: STA origin below the ECA is a common finding. Our population presented the highest percentage of TLT (10.5%) and high CB (9.8%) in literature. Considering these variations are important to prevent complications in neck surgical procedures.

Bilateral persistent stapedial arteries associated with unilateral moyamoya disease: a particular anatomic variant.

PURPOSE: The persistence of the stapedial artery is a rare vascular variant that could explain the origin of the middle meningeal artery from the petrous segment of the internal carotid artery. The anatomic variations are illustrated and a summary of the possible hypothesis of the origin of the middle meningeal artery from the internal carotid artery is discussed, analysing the embryological works of the Carnegie Institute and the vascular development of the middle meningeal. METHODS AND RESULTS: The authors present a young patient showing a particular vascular variant on diagnostic imaging. These showed a bilateral internal carotid artery that gives origin of the middle meningeal artery in a patient affected by moyamoya disease. A literature review was performed to analyze the particular variant of the radiologic anatomy. CONCLUSION: The internal carotid artery origin of the middle meningeal artery is a wonderful anatomic variant that permits to understand the complex embryological development and then involution of the stapedial artery.

Anomalous anastomosis between the external carotid artery and vertebrobasilar artery via the hypoglossal canal: a case report and review of literature.

We report a case of an anomalous anastomosis formed between the external carotid artery (ECA) and the vertebrobasilar artery (VBA) and passing through the hypoglossal canal. A carotid-vertebrobasilar anastomosis of this kind is typically considered a variant of persistent primitive hypoglossal artery which usually originates from the internal carotid artery. However, the anastomotic vessel in this case had a common trunk with the occipital artery (OA), a remnant of the primitive proatlantal artery. The proximal and distal parts of the anastomotic vessel seemed to have been derived from the primitive proatlantal artery and the primitive hypoglossal artery, respectively. Thus, we propose that this ECA-VBA anastomosis, which passed through the hypoglossal canal and had a common trunk with the OA, be referred to as a dilated primitive hypoglossal-proatlantal anastomosis; that is, a dilated ascending pharyngeal artery rather than a variant of persistent primitive hypoglossal artery.

Giant Chest Wall Arteriovenous Malformation: A Case Report and Literature Review.

BACKGROUND: We present an interesting case of a 55-year-old male with a large left chest mass after significant cutaneous bleeding. Computed tomography angiogram of the chest revealed arteriovenous malformation with blood supply from sub-branches of the left subclavian artery, left internal mammary artery, and left external carotid artery. Measuring 5.0 × 14.0 × 10.8 cm, the mass extended superior to the clavicle and inferior to the third rib with medial and lateral borders at the level of the clavicular head and coracoid, respectively. METHODS: Arteriovenous malformations (AVMs) are characterized by abnormal connections between arteries and veins which bypass the capillary system. Often small and asymptomatic, large AVMs can be painful, prone to bleeding and, if large enough, interfere with activities of daily living. While described involving various parts of the body, most notably in the central nervous system, there is a paucity of literature involving chest wall AVMs. RESULTS: Using a staged, multidisciplinary approach, treatment began with an endovascular exclusion of the arterial blood supply, which involved a combination of coil embolization and stent exclusion of feeder vessels. Two days postembolization, the patient underwent an en bloc resection of affected portion of his chest wall. Reconstruction was completed with a combination rotational flap and split-thickness skin graft. Following the procedures, the patient had an uncomplicated recovery. Three years following procedure, he has no signs of recurrence of his AV malformation. CONCLUSION: Surgical planning and indications for giant arteriovenous malformations remains a unique and difficult problem. The complex anatomy and extreme rarity of a chest wall AVM requires a multidisciplinary staged approach but can be treated with a multistage, multidisciplinary surgical approach with satisfactory and long-lasting results.

Anastomosis of the external carotid artery and the V3 segment of the vertebral artery (presumed persistent second cervical intersegmental artery) diagnosed by CT angiography.

Congenital anastomosis of the external carotid (ECA) and vertebral (VA) arteries is extremely rare. We report a case of right ECA-VA anastomosis diagnosed by computed tomography (CT) angiography. The presumed dilated ascending pharyngeal artery coursed posteriorly and entered the C1 right transverse foramen. The proximal right VA was aplastic, and the C2 right transverse foramen was absent. Based on these findings, we diagnosed congenital anastomosis of the ECA and V3 segment of the VA, which we presumed to represent persistence of the second cervical intersegmental artery. Detection of rare variations of the vertebral arteries requires careful observation of CT angiography with bone images and source images, especially to identify the level of entry into the transverse foramen. Correct diagnosis of anastomosis is important when intravascular embolization or infusion chemotherapy or surgical ligation of the ECA is planned.

A congenital external carotid artery-external jugular vein arteriovenous fistula was successfully treated by coil embolization (case report and literature review).

OBJECT: Congenital arteriovenous fistula involving the external carotid system is rare. METHODS: This paper reports a case of congenital external carotid artery-external jugular vein arteriovenous fistula admitted to Xuanwu Hospital, and reviews the literature. RESULTS: The patient was a boy, 9 years old, with a history of pulsatile mass and thrill in the right neck since his birth. External carotid artery-external jugular vein fistula was confirmed by the digital subtraction angio-graphy. And coil embolization was done later. Postoperative immediate angiography confirmed the complete occlusion of the fistula, and partial branch of the external carotid artery can be seen. The abnormal clinical manifestation disappeared after the procedure without any complications. CONCLUSION: This case and relevant literatures remind us that congenital external carotid artery-external jugular vein arteriovenous fistula has its unique features, and it can be treated by coil embolization safely and effectively.

Lateral Position of the External Carotid Artery: A Rare Variation to Be Recognized During Carotid Endarterectomy.

BACKGROUND: External carotid artery (ECA) positioned laterally to the internal carotid artery (ICA) at the level of the common carotid artery (CCA) bifurcation is occasionally encountered during carotid endarterectomy (CEA). This study aimed to determine the frequency of this phenomenon and provide technical tips for performing CEA. METHODS: The study included 199 consecutive patients (209 carotid arteries) who underwent CEA at Otaru Municipal Medical Center in 2007-2014. The position of the ECA with respect to the ICA at the CCA bifurcation was preoperatively rated as either lateral or normal, using three-dimensional computerized tomographic angiography (3-D CTA) anteroposterior projections. Postoperative diffusion-weighted images (DWIs), and postoperative 3-D CTA images were reviewed. RESULTS: Among the 209 carotid arteries with atherosclerosis, 11 instances (5.3 %) of lateral position of the ECA were detected in 11 patients. Ten of these arteries (91 %) were right-sided (odds ratio 11.1; 95 % confidence interval 1.38-88.9). Wider longitudinal exposure of the arteries was used during CEA, and the CCA and ECA were rotated clockwise or counter clockwise. The ICA lying behind the ECA along the surgical access route was then pulled out laterally and moved to the shallow surgical field. Cross-clamping, arteriotomy, plaque removal, and wall suturing were performed as usual. No cerebral infarcts were detected on postoperative DWIs, and 3-D CTA revealed no CCA and ICA kinking. CONCLUSIONS: Lateral position of the ECA is not extremely rare in patients undergoing CEA for atherosclerosis and may be a congenital variation, although this is still controversial. CEA can be performed safely if the arteries from the CCA to the ICA are rotated, and the ICA is moved to the shallow surgical field under wider longitudinal exposure. Although no postoperative cerebral infarcts were detected, the risk of artery-to-artery embolism resulting from artery repositioning prior to plaque removal should be taken into consideration.

Matrix Metalloproteinase Levels in Cervical and Intracranial Carotid Dolichoarteriopathies.

BACKGROUND: Matrix metalloproteinases (MMPs) are enzymes suggested as a possible candidate for pathogenesis of arterial dolichoarteriopathy (DA). We aimed to investigate the relationship between MMP levels and DA of intra- and extracranial carotid arteries. METHODS: This study included 88 subjects admitted with headache, vertigo, or pulsatile tinnitus and those who underwent computed tomography angiography. The study group (n = 70) consisted of patients with kink-coiling (group I, n = 41) and patients with tortuosity (group II, n = 29). The control group (n = 18) had normal angiography results. The diameter, course, and geometry of the carotid artery were analyzed. Serum MMP-1, -2, -3, and -12 levels were measured in all subjects. Vascular risk factors for DA were also noted. RESULTS: MMP-2 levels were significantly higher in the kink-coiling and tortuous groups than in the control group. In the study group (n = 70), MMP-12 levels were also significantly higher in patients with atheromatous plaques than in those without plaques. Diameters of arteries were meaningfully wider in the kink and tortuous groups than in the control group. Among vascular risk factors, hypertension and diabetes mellitus were more common in the kink group than in the control group, and there were significant differences between them. CONCLUSIONS: MMP-2 plays a role in the etiology of DA, and MMP-12 levels increase in carotid atherosclerotic lesions and may lead to plaque formation. We demonstrated that dilatation and tortuosity occur together.

Bilateral abnormal origin of the anterior branches of the external carotid artery.

BACKGROUND: Description of a rare variation is provided alongside with a review of the literature with special references to anatomic, embryologic, and clinical issues it may create. METHODS: This was a cadaveric dissection conducted during a pregraduate anatomy course that is accompanied by short review of the literature and critical appraisal. RESULTS: During dissection of the neck region of a male cadaver, the superior thyroid artery occurred from the common carotid artery bilaterally and the lingual artery occurred from the carotid bifurcation on the left side. CONCLUSIONS: Superior thyroid artery originating from common carotid artery or carotid bifurcation is a common variation, but the lingual artery originating from the common carotid artery or carotid bifurcation is very rare (<1%). Its existence can have a significant impact on treatment success and potentially lead to errors during interventions at the neck region. A high level of suspicion is required.

Multidisciplinary approach to lethal bleeding from an arteriovenous malformation in the external auditory canal.

Arteriovenous malformations (AVMs) are composed of abnormally connecting feeding arteries as well as draining veins and lack a regulatory system. Frequent recurrences and unpredictable behavior are their main problems. Potential mortality and morbidity associated with therapeutic procedures must be considered with these patients. Improper treatment often aggravates the condition, potentially rendering therapy more complex. A multidisciplinary approach, including an endovascular approach, surgical excision, and flap reconstruction, is considered to completely eradicate an AVM. This study introduces a complicated case of AVM with massive bleeding through the external auditory canal that was treated with a multidisciplinary approach.