Diameter Of Superficial Temporal Artery Research Articles

Anatomic Study of Vascular Supply of the External Ear Using CT Angiography in Congenital Microtia

Background: The morphology of the arteries of the external ear on the affected side of congenital microtia differs from normal. The present study aimed to use computed tomography angiography (CTA) to describe the anatomic variations of arteries in microtia and provide theoretical guidance for the first stage of autologous auricular reconstruction by the 2-stage method. Methods: Ten patients with unilateral microtia from May 2021 to August 2021 were included. Computed tomography angiography and 3-dimensional reconstruction were used to analyze the supply and branches of the main arteries of the auricle. The number of the superficial temporal artery (STA) and posterior auricular artery (PAA) branches to the auricle, vessel diameter, and the presence or absence of the STA and PAA branches were documented. The skin flap and incision were designed combined with the anatomic of auricular arteries. Results: The blood supply of the auricle mainly came from the STA and PAA. The STA’s preauricular branch and PAA’s posterior auricular branch were absent to varying degrees, and the middle branch was more prominent. The average diameter of the STA on the healthy auricle was 3.07±0.96 mm, and the average diameter of the PAA was 1.72±0.50 mm. The average diameter of the STA on the microtia auricle was 2.65±0.42 mm, and the average diameter of the PAA was 1.53±0.67 mm. There was a statistically significant difference in the diameter of STA between the healthy auricle and the microtia auricle (P=0.006). However, there was no significant difference in the diameter of the PAA between the healthy auricle and the microtia auricle (P=0.112). The skin flap and incision were designed and combined with the preoperative CTA images, and no flap necrosis was observed in all patients. Conclusion: The vascular distribution of arteries in microtia patients was clearly and accurately assessed by CTA. In our experience, the data and detailed imaging were useful in designing skin flaps and incisions during the first stage of autologous auricular reconstruction by the 2-stage method.

Non-vascular ATP-sensitive potassium channel activation does not trigger migraine attacks: A randomized clinical trial.

To investigate the role of NN414, a selective KATP channel opener for the Kir6.2/SUR1 channel subtype found in neurons and β-pancreatic cells, in inducing migraine attacks in individuals with migraine without aura. Thirteen participants were randomly allocated to receive NN414 and placebo on two days separated by at least one week. The primary endpoint was the difference in the incidence of migraine attacks after NN414 compared with placebo. The secondary endpoints were the difference in the area under the curve for headache intensity scores, middle cerebral artery blood flow velocity (VMCA), superficial temporal artery diameter, heart rate and mean arterial pressure. Twelve participants completed the study, with two (16.6%) reporting migraine attacks after NN414 compared to one (8.3%) after placebo (p = 0.53). The area under the curve for headache intensity, VMCA, superficial temporal artery diameter, heart rate and mean arterial pressure did not differ between NN414 and placebo (p > 0.05, all comparisons). The lack of migraine induction upon activation of the Kir6.2/SUR1 channel subtype suggests it may not contribute to migraine pathogenesis. Our findings point to KATP channel blockers that target the Kir6.1/SUR2B subtype, found in cerebral vasculature, as potential candidates for innovative antimigraine treatments.Registration number: NCT04744129.

Assessing the Adequacy of Superficial Temporal Artery Blood Flow in Korean Patients Undergoing STA-MCA Anastomosis.

Superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis is conducted for flow augmentation. In this study, we measured the STA cut flow of a Korean population and evaluated the relationship between STA cut flow and long-term patency of the bypass. A retrospective study was conducted. Intraoperative measurement of STA flow was conducted using a microvascular flow meter on patients who underwent STA-MCA. After cutting the distal end, the STA flow rate was measured with no resistance and recorded. After finishing anastomosis, STA flow was measured and recorded. The cut flow index was calculated by dividing post anastomosis flow by cut flow in intracranial atherosclerotic stenosis patients. The median STA cut flow was 35.0 mL/min and the post anastomosis flow was 24.0 mL/min. The cut flow of STA decreased with aging (p=0.027) and increased with diameter (p=0.004). The cut flow showed no correlation with history of hypertension or diabetes mellitus (p=0.713 and p=0.786), but did correlate a positively with history of hyperlipidemia (p=0.004). There were no statistical differences in cut flow, STA diameter, and post anastomosis flow between the frontal and parietal branches (p=0.081, p=0.853, and p=0.990, respectively). The median STA cut flow of a Korean population was 35 mL/min. Upon reviewing previous articles, it appears that there are differences in the STA cut flow between Western and Asian patients.

The vascular role of CGRP: a systematic review of human studies.

Intravenous infusion of human alpha calcitonin gene-related peptide (h-α-CGRP) has been applied to explore migraine pathogenesis and cerebral hemodynamics during the past three decades. Cumulative data implicate h-α-CGRP in regulating the vascular tone. In this systematic review, we searched PubMed and EMBASE for clinical studies investigating the vascular changes upon intravenous infusion of h-α-CGRP in humans. A total of 386 studies were screened by title and abstract. Of these, 11 studies with 61 healthy participants and 177 participants diagnosed with migraine were included. Several studies reported hemodynamic effects including flushing, palpitation, warm sensation, heart rate (HR), mean arterial blood pressure (MABP), mean blood flow velocity of middle cerebral artery (mean VMCA), and diameter of superficial temporal artery (STA). Upon the start of h-α-CGRP infusion, 163 of 165 (99%) participants had flushing, 98 of 155 (63%) participants reported palpitation, and 160 of 165 (97%) participants reported warm sensation. HR increased with 14%-58% and MABP decreased with 7%-12%. The mean VMCA was decreased with 9.5%-21%, and the diameter of the STA was dilated with 41%-43%. The vascular changes lasted from 20 to >120 min. Intravenous infusion of h-α-CGRP caused a universal vasodilation without any serious adverse events. The involvement of CGRP in the systemic hemodynamic raises concerns regarding long-term blockade of CGRP in migraine patients with and without cardiovascular complications.

The effect of Lu AG09222 on PACAP38- and VIP-induced vasodilation, heart rate increase, and headache in healthy subjects: an interventional, randomized, double-blind, parallel-group, placebo-controlled study

BackgroundPituitary adenylate cyclase-activating polypeptide (PACAP), structurally related to vasoactive intestinal peptide (VIP), is one of the important mediators in the pathogenesis of migraine and is known to dilate cranial arteries and induce headache and migraine. Our objective was to determine whether Lu AG09222—an investigational humanized monoclonal antibody directed against PACAP ligand—would inhibit the PACAP-signaling cascade by abolishing its vasodilatory and headache-inducing abilities.MethodsIn a randomized, double-blind, parallel-group, single-dose, placebo-controlled study of Lu AG09222, healthy volunteers aged 18–45 years without history of headache disorders were randomly allocated to three treatment sequences (1:2:2) on two experimental infusion visits with 9 ± 3 days’ interval: placebo + saline + saline (n = 5), placebo + PACAP38 + VIP (n = 10), and Lu AG09222 + PACAP38 + VIP (n = 10). The primary outcome measure was area under the curve (AUC) of the change in superficial temporal artery (STA) diameter from 0 to 120 min after start of infusion of PACAP38. The study was conducted at the Danish Headache Center in Copenhagen, Denmark.ResultsIn participants who received Lu AG09222 + PACAP38 infusion, there was a significantly lower STA diameter (mean (SE) [95% CI] AUC ‒35.4 (4.32) [‒44.6, ‒26.3] mm × min; P < 0.0001) compared to participants who received placebo + PACAP38 infusion. Secondary and explorative analysis revealed that PACAP38 infusion induced an increase in facial blood flow, heart rate and mild headache, and indicated that these PACAP38-induced responses were inhibited by Lu AG09222.ConclusionsThis proof-of-mechanism study demonstrated that Lu AG09222 inhibited PACAP38-induced cephalic vasodilation and increases in heart rate, and reduced concomitant headache. Lu AG09222 may be a potential therapy against migraine and other PACAP-mediated diseases.Trial registrationClinicalTrials.gov: NCT04976309. Registration date: July 19, 2021.Graphical

Cerebrovascular Reserve Impairment in the Anterior Cerebral Artery Territory Predicts Deep Temporal Artery Enlargement After Combined Revascularization Surgery in Moyamoya Disease.

A combined surgery of direct and indirect revascularization has been frequently performed in patients with moyamoya disease, though the efficacy of indirect revascularization surgery in adult patients with moyamoya disease has not been established. This study aimed to evaluate superficial temporal artery (STA) and deep temporal artery (DTA) diameters 1day and 3months after combined revascularization surgery in patients with moyamoya disease. We also investigated clinical factors related to DTA enlargement after surgery. We examined 78 cerebral hemispheres in 57 adult and pediatric patients with moyamoya disease who underwent combined revascularization surgery [STA-MCA bypass and encephalo-duro-myo-synangiosis] in our institution. STA and DTA diameters were measured on axial magnetic resonance angiography images at 1day and 3months after surgery. DTA diameter increased in 64 hemispheres (82.1%). DTA diameter increase in association with STA diameter decrease was found in 39 hemispheres (50%). The proportion of hemispheres with a reduction in STA diameter was significantly higher in hemispheres with DTA enlargement than in hemispheres with DTA reduction (P=0.0088). Among the 64 hemispheres with DTA enlargement, 51 (79.7%) showed cerebrovascular reserve (CVR) impairment in the anterior cerebral artery (ACA) territory before surgery. CVR impairment in the ACA territory was the only clinical factor related to DTA enlargement (P<0.001). The DTA frequently enlarges after combined revascularization surgery, even in adult patients with moyamoya disease. In patients with impaired CVR in the ACA territory, blood supply from the DTA to the ACA territory can be expected after combined revascularization surgery.

Effect of KATP channel blocker glibenclamide on PACAP38-induced headache and hemodynamic

To determine whether glibenclamide, a non-selective adenosine 5'-triphosphate-sensitive K+ (KATP) channel blocker, attenuates pituitary adenylate cyclase-activating polypeptide-38 (PACAP38)-induced headache and vascular changes in healthy volunteers. In a double-blind, randomized, placebo controlled and crossover design, 22 healthy volunteers were assigned to receive an intravenous infusion of 10 picomole/kg/min pituitary adenylate cyclase-activating polypeptide-38 over 20 minutes followed by oral administration of 10 mg glibenclamide or placebo. The primary endpoint was the difference in incidence of headache (0-12 hours) between glibenclamide and placebo. The secondary endpoints were a difference in area under the curve for headache intensity scores, middle cerebral artery velocity (VmeanMCA), superficial temporal artery diameter, radial artery diameter, heart rate, mean arterial blood pressure and facial skin blood flow between the two study days. Twenty participants completed the study. We found no difference in the incidence of pituitary adenylate cyclase-activating polypeptide-38-induced headache after glibenclamide (19/20, 95%) compared to placebo (18/20, 90%) (P = 0.698). The area under the curve for headache intensity, middle cerebral artery velocity, superficial temporal artery diameter, radial artery diameter, facial skin blood flow, heart rate and mean arterial blood pressure did not differ between pituitary adenylate cyclase-activating polypeptide-38-glibenclamide day compared to pituitary adenylate cyclase-activating polypeptide-38-placebo day (P > 0.05). Posttreatment with 5'-triphosphate-sensitive K+ channel inhibitor glibenclamide did not attenuate pituitary adenylate cyclase-activating polypeptide-38-induced headache and hemodynamic changes in healthy volunteers. We suggest that pituitary adenylate cyclase-activating polypeptide-38-triggered signaling pathway could be mediated by specific isoforms of sulfonylurea receptor subunits of 5'-triphosphate-sensitive K+ channels and other types of potassium channels.

Effect of Vasoactive Intestinal Polypeptide on Development of Migraine Headaches

Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptides (PACAPs) are structurally and functionally related, yet different in their migraine-inducing properties. It remains unclear whether the lack of migraine induction can be attributed to the only transient vasodilatory response after a 20-minute infusion of VIP. To determine whether a 2-hour infusion of VIP would provoke migraine attacks. A randomized, double-blind, placebo-controlled, crossover study was conducted between May and September 2020 at the Danish Headache Center in Copenhagen, Denmark. Patients were eligible for inclusion if they were ages 18 to 40 years, weighed between 50 and 90 kg, had a diagnosis of migraine without aura as defined by the International Classification of Headache Disorders, and had a migraine frequency of 1 to 6 attacks per month. Patients were randomly allocated to receive a 2-hour infusion of VIP or placebo on 2 different days. The primary end point was the difference in incidence of experimentally induced migraine attacks during the observational period (0-12 hours) between VIP and placebo. Twenty-one patients (17 [81%] women and 4 [19%] men; mean [range] age, 25.9 [19-40] years) were recruited in the study. Fifteen patients (71%; 95% CI, 48%-89%) developed migraine attacks after VIP compared with 1 patient (5%; 95% CI, 0%-24%) who developed a migraine attack after placebo (P < .001). The VIP-induced migraine attacks mimicked patients' spontaneous attacks. The area under the curve (AUC) of headache intensity scores (0-12 hours), as well as the AUC of the superficial temporal artery diameter (0-180 minute) were significantly greater after VIP compared with placebo (AUC0-12h, P = .003; AUC0-180min, P < .001). A 2-hour infusion of VIP caused migraine attacks, suggesting an important role of VIP in migraine pathophysiology. VIP and its receptors could be potential targets for novel migraine drugs. ClinicalTrials.gov Identifier: NCT04260035.

Long-Term Patency and Final Structure After Superficial Temporal Artery–Middle Cerebral Artery Bypass Surgery: A Retrospective Study

To investigate long-term bypass patency and final structure for patients who underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass. This study retrospectively evaluated 20 patients who underwent STA-MCA bypass and had 2-year follow-up with cerebral angiography. Patients were divided into internal carotid artery occlusion (n= 11) and MCA occlusion or stenosis (n= 9) groups, and diagnosis was either arteriosclerotic (n= 14) or nonarteriosclerotic (n= 6) disease. Final bypass formation was examined with cerebral angiography at 2 years postoperatively. Diameters of the STA, middle meningeal artery (MMA), and deep temporal artery (DTA) were measured at preoperative angiography and at 2-year follow-up. No significant differences in STA, MMA, and DTA diameters were reported between the internal carotid artery versus MCA group. For patients with arteriosclerotic disease, thicker STA diameters were noted on preoperative angiography. For patients with nonarteriosclerotic disease, MMA and DTA dilatation was noted on 2-year follow-up imaging. For patients with arteriosclerotic disease, all direct bypasses were patent at 2 years. For patients with nonarteriosclerotic disease, remarkable angiogenesis was demonstrated. Long-term patency of a direct bypass may be correlated with arteriosclerotic or nonarteriosclerotic etiology. An indirect bypass route may develop in patients with nonarteriosclerotic disease; therefore, it is important to create a foundation for an indirect bypass with MMA and DTA preservation during craniotomy. In 2 patients with nonarteriosclerotic disease, STA remained the primary bypass foundation; however, the technique resembled novel angiogenesis after encephaloduroarteriosynangiosis and not direct STA-MCA bypass. Therefore, final bypass structure might be affected by disease etiology.

Opening of BKCa channels alters cerebral hemodynamic and causes headache in healthy volunteers.

Preclinical data implicate large conductance calcium-activated potassium (BKCa) channels in the pathogenesis of headache and migraine, but the exact role of these channels is still unknown. Here, we investigated whether opening of BKCa channels would cause headache and vascular effects in healthy volunteers. In a randomized, double-blind, placebo-controlled, cross-over study, 21 healthy volunteers aged 18-39 years were randomly allocated to receive an intravenous infusion of 0.05 mg/min BKCa channel opener MaxiPost and placebo on two different days. The primary endpoints were the difference in incidence of headache and the difference in area under the curve (AUC) for headache intensity scores (0-12 hours) and for middle cerebral artery blood flow velocity (VMCA) (0-2 hours) between MaxiPost and placebo. The secondary endpoints were the differences in area under the curve for superficial temporal artery and radial artery diameter (0-2 hours) between MaxiPost and placebo. Twenty participants completed the study. Eighteen participants (90%) developed headache after MaxiPost compared with six (30%) after placebo (p = 0.0005); the difference of incidence is 60% (95% confidence interval 36-84%). The area under the curve for headache intensity (AUC0-12 hours, p = 0.0003), for mean VMCA (AUC0-2 hours, p = 0.0001), for superficial temporal artery diameter (AUC0-2 hours, p = 0.003), and for radial artery diameter (AUC0-2 hours, p = 0.03) were significantly larger after MaxiPost compared to placebo. MaxiPost caused headache and dilation in extra- and intracerebral arteries. Our findings suggest a possible role of BKCa channels in headache pathophysiology in humans. ClinicalTrials.gov, ID: NCT03887325.

Two-hour infusion of vasoactive intestinal polypeptide induces delayed headache and extracranial vasodilation in healthy volunteers.

In recent years, vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptides (PACAPs) have gained special interest in headache science. VIP and PACAPs (two isoforms, PACAP27 and PACAP38) are related in structure and function, as are their receptors, but they show differences in vasodilating- and headache-inducing properties. Intravenous infusion of PACAP27 or PACAP38, but not VIP, induces a long-lasting dilation of cranial arteries and delayed headache. The relationship between the long-lasting cranial vasodilation and headache development is not fully clarified. In a double-blinded, placebo-controlled, crossover study in 12 healthy volunteers, diameter changes of cranial arteries, occurrence of headache and the parasympathetic system were examined before, during and after a 2-hour continuous intravenous infusion of VIP and placebo. Primary endpoints were the differences in area under the curve for the superficial temporal artery diameter and headache intensity scores, as well as in headache incidence, between VIP and placebo. The superficial temporal artery diameter was significantly larger on the VIP day compared to placebo (p < 0.001) and the dilation lasted for more than 2 h. The incidence of headache was higher (p = 0.003) on the VIP day compared to the placebo day. The difference in headache intensity scores was more evident in the post-infusion period (120-200 min, p = 0.034) and in the post-hospital phase (4-12 h, p = 0.025). Cranial parasympathetic activity, measured through the production of tears, was higher during VIP compared to placebo (p = 0.033). Continuous intravenous infusion of VIP over 2 h induced a long-lasting cranial vasodilation, activation of the cranial parasympathetic system, and delayed mild headaches in healthy volunteers.Trial Registration: The study is registered at ClinicalTrials.gov (NCT03989817).

The superficial temporal artery: A meta-analysis of its prevalence and morphology.

The superficial temporal artery (STA) is a terminal branch of the external carotid artery. It supplies the regions of scalp and face. The morphometrical data concerning STAs are not consistent; therefore, in this systemic review and meta-analysis, we aimed in this to provide an up-to-date data on its anatomic features. In order to do this, PubMed, Embase, ScienceDirect, and Web of Science were searched. We followed the Preferred Reporting Items and Review and Meta-Analyses guidelines for the meta-analysis. Studies that reported the prevalence and anatomical data regarding STA were included in further analyses. Out of 1,446 studies initially evaluated, 21 were included in the meta-analysis (874 patients/donors). The STA diameter was 1.5 mm (95% confidence interval [CI]: 1.47-1.53 mm). The frontal and parietal branches of the STA were present in 97.6% (95% CIs: 94.6-99.5%) and 96.4% (95% CIs: 93.5-98.5%) of the cases, respectively. The STA bifurcation point was located above the zygomatic arch in 79.1% (95% CI: 68.0-84.3), below the zygomatic arch in 6.7% (95% CI: 2.4-12.1), and on the zygomatic arch in 11.1% of the cases (95% CI: 5.4-17.5). There was no bifurcation of the STA in 3.1% of the cases (95% CI: 0.4-7.3). The most comprehensive analysis of STA morphological features is presented. The results from this evidence-based anatomical study will improve understanding of the clinical STA anatomy, which in turn has major implications for understanding the STA in clinical practice.

Association of Superficial Temporal Artery Dilatation with Headache After Revascularization in Adult Moyamoya Disease

The underlying mechanisms of headache in adult moyamoya disease (MMD) are not clear. The aim of this study is to clarify the factors that are associated with headache in adult patients with MMD after superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis. We retrospectively analyzed the cases of 68 adult patients with MMD: 30 with surgery and 38 without surgery. Each STA-MCA anastomosis was performed by the standard technique. Magnetic resonance angiography (MRA) and single photon emission computed tomography were performed perioperatively. We stratified the intensity and frequency of the patients' headaches into 4 ranks. Pre- and postoperative STA diameters were retrospectively measured on digital subtraction angiography (DSA) and/or MRA. In the surgery group, preoperative regional cerebral blood flow (rCBF) laterality and a postoperative rCBF increase >20% showed no significant difference between the patients with and without headache with a univariate analysis. The postoperative STA diameters of the distal branch (DSA) and main trunk (DSA/MRA) in the patients with headache were significantly larger than those of the patients without headache. The rate of postoperative increase of the STA diameters of the distal branch/main trunk was also significantly higher in the patients with headache than those without headache. A multivariate analysis showed that the standard regression coefficient β for sex, a >20% increase of postoperative rCBF, and the increase rate of the STA diameter of the distal branch shown by DSA was 0.37, 0.54, and 0.56, respectively. The results of our analyses revealed that aside from ischemia, the postoperative increase rate of the STA may be a candidate reason for headache, especially in adult patients with MMD.

Superficial temporal artery-to-middle cerebral artery bypass in combination with indirect revascularization in moyamoya patients ≤ 3 years of age.

OBJECTIVE Revascularization is indicated in the management of moyamoya disease (MMD), with options that include direct and indirect techniques. Indirect bypass is popular in young children because the diminutive caliber of donors and recipients makes direct bypass difficult. The authors reviewed a series of patients treated with direct superficial temporal artery (STA)–to–middle cerebral artery (MCA) bypass in combination with encephalomyosynangiosis (EMS) in children 3 years or younger to demonstrate feasibility and safety. METHODS A retrospective review of all surgeries for MMD over a 19-year period identified 11 procedures in 6 patients. Surgical results, angiographic outcomes, and clinical outcomes were analyzed. RESULTS Patients had a mean age of 22.4 months. The symptomatic hemisphere was revascularized first, and the contralateral hemisphere was revascularized on average 2.8 months later in 5 patients. All direct bypasses were patent postoperatively and remained patent at late follow-up (mean 4.1 years), with both STA and MCA diameters increasing significantly (n = 5, p < 0.03). At last follow-up (mean follow-up duration, 5.0 years), favorable outcomes (modified Rankin Scale scores 0–2) were observed in 5 of the 6 patients (83%), with 1 dependent patient remaining unchanged postoperatively. CONCLUSIONS Direct STA-MCA bypass in combination with EMS for MMD is feasible and safe in patients 3 years or younger, based on favorable clinical and radiological outcomes in this patient cohort. Direct bypass should be considered when immediate revascularization is needed, without the biological delay associated with indirect bypass. ABBREVIATIONS EDAS = encephaloduroarteriosynangiosis; EMS = encephalomyosynangiosis; MCA = middle cerebral artery; MMD = moyamoya disease; mRS = modified Rankin Scale; STA = superficial temporal artery; TIA = transient ischemic attack.

Time-of-flight MRA signal intensity predicts the cerebral hemodynamic status after superficial temporal artery to middle cerebral artery anastomosis

Arterial signal intensities on magnetic resonance angiography (MRA) correlate with the relevant hemisphere’s hemodynamics in patients with cerebrovascular diseases. We evaluated whether superficial temporal artery (STA) signal intensities (SI) on MRA were useful to evaluate the postoperative cerebral hemodynamics of patients with symptomatic internal carotid artery (ICA) or middle cerebral artery (MCA) steno-occlusive disease who underwent unilateral STA-MCA anastomosis. Twenty-one consecutive patients undergoing unilateral STA-MCA anastomosis for symptomatic ICA or MCA steno-occlusive disease were enrolled. All patients underwent MRA and superficial temporal artery duplex ultrasonography (STDU) at 3 months and 1 year postoperatively. Bilateral region of interests (ROIs) on time-of-flight (TOF)-MRA source images were placed on the STA just before its bifurcation. The STA-SI ratio, which was the ratio of the SI on the operated STA to that of the contralateral STA, was calculated; the correlation between the ratio and STDU parameters was investigated. The STA diameter and flow velocities (systolic, end-diastolic, and mean) significantly correlated with the STA-SI ratio at 1 year postoperatively (p = .0302, p = .0002, p = .0029, p = .002). The end-diastolic flow velocity ratio was significantly correlated with the STA-SI ratio at 1 year postoperatively (p = .0014, r = 0.6518). The STA-SI ratio can be used to predict the extent of postoperative collateral bypass flow, and it may help predict postoperative cerebrovascular reserve.

Postoperative Dilatation of Superficial Temporal Artery Associated with Transient Neurologic Symptoms After Direct Bypass Surgery for Moyamoya Angiopathy.

In moyamoya angiopathy, transient neurologic symptoms (TNS) are occasionally observed after superficial temporal artery (STA)-middle cerebral artery direct bypass surgery. The purpose of this study was to investigate the correlation between TNS and postoperative magnetic resonance imaging as well as perform a perfusion study. We reviewed 52 hemispheres in 33 consecutive patients with moyamoya angiopathy. TNS were defined as reversible neurologic dysfunction without any apparent intracranial infarction or hemorrhage. All patients underwent magnetic resonance imaging and single-photon emission computed tomography before and within 5 days after surgery. Maximum diameter of STA on time-of-flight magnetic resonance angiography and the dilatation ratio of STA were calculated. The presence of signal changes on fluid-attenuated inversion recovery images and regional cerebral blood flow were also evaluated. TNS were observed in 13 of 52 (25%) cases1-16 days after surgery. The mean preoperative STA dilatation, postoperative STA dilatation, and dilatation ratio of STA were 1.33 mm ± 0.27, 1.67 mm ± 0.30, and 29.31% ± 28.13%. Postoperative intraparenchymal cortical hyperintensity lesions and high-intensity signals in the cortex sulci (ivy sign) were detected in 24 (46.2%) cases and 29 (55.8%) cases, respectively. Univariate analyses demonstrated no association between TNS and postoperative signal change on fluid-attenuated inversion recovery images as well as cerebral blood flow. Only>1.5-fold dilatation of STA was significantly correlated with TNS (P < 0.0001). STA dilatation was correlated with TNS after direct bypass surgery for moyamoya angiopathy.

Intraoperative middle cerebral artery pressure measurements during superficial temporal artery to middle cerebral artery bypass procedures in patients with cerebral atherosclerotic disease.

OBJECTIVE No previous study has monitored middle cerebral artery (MCA) pressure during the superficial temporal artery (STA)-MCA bypass procedure for cerebral atherosclerotic disease. In this paper, the authors describe their method of monitoring MCA pressure and report their initial data on intraoperative MCA pressure and its relationship with hemodynamics prior to and after the bypass procedures. METHODS The results from a total of 39 revascularization procedures performed between 2004 and 2014 were analyzed. The patient group included 27 men and 12 women, and their mean age at surgery was 67.6 years (range 39-83 years). The authors investigated the MCA pressure via the STA during STA-MCA bypass procedures. After one branch of the STA was anastomosed to the MCA, the other branch was connected to an arterial line, and a clip was placed temporally on the main STA trunk to monitor the pre-anastomosis MCA pressure. Simultaneously, the radial artery (RA) pressure was determined before removing the temporal clip to measure the post-anastomosis MCA pressure. The relationship between MCA pressures and single photon emission computed tomography findings and the risk factors for hyperperfusion after STA-MCA bypass were analyzed. RESULTS The MCA/RA (%) pressure was significantly correlated with that of the resting stenotic/normal side cerebral blood flow (CBF) ratio (%) in the linear regression analysis (slope 1.200, r2 = 0.3564, F = 20.49, p < 0.0001). The intraoperative MCA pressure was 39.3% of RA pressure in patients with Powers' Stage 2 cerebral atherosclerotic disease. After 1 branch of the STA was anastomosed, the intraoperative MCA pressure increased to 75.3% of the RA pressure. The rate of increase in pressure was significantly correlated with the increase in the STA diameter in the linear regression analysis (slope 2.59, r2 = 0.205, F = 9.549, p = 0.0038). Hyperperfusion occurred in 2 cases. When mean values for these 2 patients were compared with those for the 37 patients without hyperperfusion, significant differences were found in the stenotic/normal side CBF ratio (p = 0.0001), pre-anastomosis MCA pressure (p = 0.02), rate of increase in pressure (p = 0.02), pre-anastomotic MCA/RA pressure ratio (p = 0.01), vascular reserve (p = 0.0489), and STA diameter (p = 0.0002). CONCLUSIONS The measurement of intraoperative MCA pressure may be a useful technique to assess cerebral perfusion and for predicting the risk of hyperperfusion. Monitoring MCA pressure is recommended during STA-MCA bypass procedures for atherosclerotic disease.

Anatomical variants of the superficial temporal artery in patients with microtia: a pilot descriptive study.

Superficial temporal artery (STA) based pedicled fascial flap plays a pivotal role in ear reconstruction for microtia patients. There is paucity of literature on the anatomy of the STA in microtia patients. The present study aimed to describe any possible anatomical variations seen in the STA of patients afflicted with microtia. Pre-operative carotid computer tomographic angiography images of patients under the microtia database of Plastic and Reconstructive Surgery Unit at a tertiary medical centre were selected and 3-dimensionally reconstructed. Measurements were made on the 3D reconstructed computed tomographic angiography images of the STA on both the sides of the microtic ear and the non-microtic ear to assess its various anatomical parameters. We managed to obtain a total of 39 computed tomographic angiography images of STAs for analysis. There was a significant difference in the number of main branches of STA between the two groups (P=0.006). The proportion of ears with 2 main branches was higher in the non-microtia group (89.5%) compared to the microtia group (45.0%). A significant difference was found in the STA diameter between the two groups (P=0.012). The mean diameter of STA in the non-microtia group was larger by 0.4 mm. Furthermore, the median angle of STA was larger on the side of the non-microtic ears compared to that of microtic ears by 24.5°, with a P-value of 0.011. The results of the study may be of clinical importance while planning and performing ear reconstructive surgeries using STA based pedicled fascial flaps.

Reduced cranial parasympathetic tone during the remission phase of cluster headache.

Cluster headache (CH) attacks are accompanied by cranial autonomic symptoms indicative of parasympathetic hyperactivity and sympathetic dysfunction ipsilateral to the pain. We aimed to assess cranial autonomic function in CH patients during the remission phase of cluster headache. During a remission phase, 38 episodic CH patients underwent the following: dynamic pupillometry, measurement of the superficial temporal artery diameter by ultrasound, and measurement of the retinal vessel diameters from digital retinal photographs. Pupillometry was also performed on 30 age- and sex-matched healthy controls. Thirty patients were included (27 men, three women, mean age 50.2 years ± 12.6). Seven patients reported occasional side shift of their headache, but with a clear predominating side. Significantly reduced average pupillary constriction velocity and retinal venular diameter on the CH pain side were found. There was no asymmetry of the superficial temporal artery diameters. Compared to healthy controls, cluster patients displayed bilaterally reduced pupillary average and maximum constriction velocities, reduced constriction in percentage and increased latency of the light reflex. The present findings indicate a bilaterally reduced cranial parasympathetic tone in CH patients in remission phase, with significant lateralization to the CH pain side. This implies a central origin, and a central pathophysiological model of CH is discussed.

The pharmacological effect of BGC20-1531, a novel prostanoid EP4 receptor antagonist, in the Prostaglandin E2 human model of headache

Using a human Prostaglandin E2 (PGE2) model of headache, we examined whether a novel potent and selective EP4 receptor antagonist, BGC20-1531, may prevent headache and dilatation of the middle cerebral (MCA) and superficial temporal artery (STA). In a three-way cross-over trial, eight healthy volunteers were randomly allocated to receive 200 and 400 mg BGC20-1531 and placebo, followed by a 25-min infusion of PGE2. We recorded headache intensity on a verbal rating scale, MCA blood flow velocity and STA diameter. There was no difference in headache response or prevention of the dilation of the MCA or the STA (P > 0.05) with either dose of BGC20-1531 relative to placebo, although putative therapeutic exposures were not reached in all volunteers. In conclusion, these data suggest that the other EP receptors may be involved in PGE2 induced headache and dilatation in normal subjects.