Distal Extracranial Internal Carotid Artery Research Articles

Lower Cranial Neuropathies as Presenting Symptom of Distal Extracranial Internal Carotid Artery Dissection Leading to Delay in Diagnosis and Treatment (P7-5.030)

Lower Cranial Neuropathies as Presenting Symptom of Distal Extracranial Internal Carotid Artery Dissection Leading to Delay in Diagnosis and Treatment (P7-5.030)

Isolated Hypoglossal Nerve Palsy due to Spontaneous Internal Carotid Artery Dissection: Two Cases Report and Review of the Literature

We report on 2 patients who presented to the ear, nose, and throat (ENT) clinic. Clinical examination demostrated tongue deviation towards the left side, without other neurological symptoms. Imaging studies, Neck CT and MR angiograms, revealed intramural haematoma, thickening and stenosis of the right distal extracranial internal carotid artery (ICA) consistent with spontaneous dissection.

Nimodipine reduces delayed cerebral vasospasm after intracranial tumour surgery: A Retrospective Study.

Cerebral vasospasm (CVS) is a frequent and serious neurosurgical complication, without sufficient therapy. This retrospective study was performed to analyze if nimodipine can improve prognosis and reduce ischaemia secondary to delayed CVS after intracranial tumour surgery. A retrospective review was performed over the years 2011 to 2012 for patients with an anterior cranial fossa tumour and underwent intracranial tumour surgery. The surgical field was soaked with nimodipine solution or normal saline. Transcranial Doppler ultrasonography was used to measure velocity in the middle cerebral artery (MCA) and the distal extracranial internal carotid artery (eICA). Follow-up was performed using the Glasgow Outcome Scale (GOS) after discharge. There were 94 patients that met the inclusion criteria. They included 50males and 44 females, with a mean age of 49.6years. In the nimodipine group, CVS occurred in 13 patients; 9 patients had CVS between 4 and 7days, and 4had CVS between 8 and 14days. In the normal saline group, 19 patients had CVS, 3 presented with CVS within 3days, 11 between 4-7days and 5 between 8-14days. A significant difference in the occurrence of CVS was observed between the two groups. Preoperative and postoperative the MCA velocities were compared, revealing a significant change in the normal saline group but not in the nimodipine group. Nimodipine markedly improves prognosis and significantly reduces ischaemia secondary to delayed CVS after intracranial tumour surgery, as well as the risks of mortality and morbidity.

Contrast-enhanced transoral carotid ultrasonography for the evaluation of a long stenotic lesion in the internal carotid artery.

Key Clinical MessageContrast‐enhanced transoral carotid ultrasonography (CETOCU) is a novel modality for imaging the distal extracranial internal carotid artery, which is not possible with conventional carotid ultrasonography. We present a representative case that demonstrates the usefulness of CETOCU.

Surgical treatment of distal extracranial internal carotid artery aneurysms associated with pathological artery kinking

Extracranial internal carotid artery (ICA) aneurysms located at the entrance of the skull are a rare pathology. Surgical treatment is indicated for this pathology because of the risk of arterio-arterial embolism and the development of cerebrovascular disease. The domestic and international literature reports single cases or small group cases of successful surgical treatment of patients with distal internal carotid artery aneurysms associated with pathological kinking of the artery. Open surgery for aneurysms of this localization is complicated because of a high injury risk associated with the approach. Endovascular interventions are not always possible due to the presence of degenerative changes in the vascular wall and pathological artery kinking. We propose a surgical option for creating a high-flow ec-ic bypass between the external carotid artery and the M2 segment of the middle cerebral artery. The article describes the results of successful application of this technique in three patients with distal extracranial internal carotid artery aneurysms associated with pathological kinking of the artery.

The location of origin of spontaneous extracranial internal carotid artery dissection is adjacent to the skull base

The traditional view is that spontaneous extracranial internal carotid artery (ICA) dissection (CAD) extends cranially from an intimal tear located just beyond the carotid bulb. This paper demonstrates that CAD originates in and primarily involves a more distal segment of the artery. A retrospective study of 54 dissected ICAs in 50 consecutive patients with spontaneous or traumatic CAD was undertaken. The site of the dissection, presence of ICA redundancy, rate of acute or delayed ischaemic stroke and vessel remodelling were determined. Of the 51 dissections that occurred spontaneously or after indirect trauma, 25/51 (49.0%) were solely in the distal third of the artery, and 49/51 (96.1%) involved the distal two-thirds. Only 2/51 (3.9%) originated in the proximal third. ICA redundancy was seen in 27/36 (75%) of patients with spontaneous CAD, compared with only 1/11 (9.1%) of those with CAD due to indirect trauma (P = 0.0002). Acute stroke occurred in 10/12 (83.3%) of patients with ICA occlusion secondary to CAD and in 14/38 (36.8%) with non-occlusive CAD (P = 0.0074). Where follow-up was available, only 2/32 (6.3%) patients had a stroke after diagnosis, and 19/33 (57.6%) ICAs recanalised or remodelled. CAD occurring spontaneously or due to indirect trauma most frequently involves the distal extracranial ICA. Spontaneous CAD is associated with vessel redundancy, and the risk of acute stroke is greatest with occlusive CAD. The prognosis is good with treatment, with a low rate of recurrent stroke and a high rate of vessel remodelling.

Open and Endovascular Repair of Aneurysms Affecting the Distal Extracranial Internal Carotid Artery: A Case Series

Open and Endovascular Repair of Aneurysms Affecting the Distal Extracranial Internal Carotid Artery: A Case Series

Value of transoral carotid ultrasonography in detecting the change of distal extracranial internal carotid artery with stenosis and occlusion in its initial segment

Objective To investigate the value of transoral carotid ultrasonography (TOCU) in detecting the change of distal extracranial internal carotid artery(ICA) with stenosis and occlusion in its initial segmen.Methods One hundred and ten patients with stenosis at least 50％ or occlusion in the initial segment of ICA diagnosed by high-frequency linear probe were enrolled as case group,while thirty two with healthy carotid arteries as control group.Both of the case and control groups were undergone high-frequency linear probe to examine CCA and the initial segment of ICA,and TOCU to observe their lumen transparency,color Doppler flow display and change of Doppler flow spectrum,even measuring the internal diameter,peak systolic velocity (PSV),end-diastolic velocity(EDV) and PSVICA/PSVCCA ratio,respectively.Digital subtraction angiography (DSA)were performed within two weeks,then compared with ultrasonography.Results 92.7％ patients were performed TOCU examination in case group and 93.8％ in control group.The internal diameter and PSV of the distal extracranial ICA became gradually smaller from control group to near occlusion group,and there were statistical significance between groups ( P ＜0.05),however,near occlusion group had no statistical significance compared with occlusion group( P ＞0.05).There were 80％ arteries having thrombus echo in occlusion group,and the others in this group having no thrombus had gloomy colour flow,even got low-velocity artery spectrum.Doppler flow spectrum of distal extracranial ICA showed characteristics of slow wave or single peak in near occlusion group,and spike shape or slow wave in 76.7 ％ arteries of 70％ ～near-occlusion stenosis group,but spike shape in 30.8％ arteries of 50％～69％ stenosis group,and the others were normal.Conclusions TOCU is useful for detecting the changing regularity of distal extracranial ICA with stenosis or occlusion in its initial segment and has the value of clinical application in association with high-frequency linear probe. Key words: Endosonography; Carotid stenosis; Hemodynamic phenomena

Hybrid (Open and Endovascular) Repair of Distal Extra-cranial Internal Carotid Artery Aneurysm

This paper describes a hybrid repair of a distal extra-cranial internal carotid artery aneurysm involving open surgical transposition of the internal carotid artery followed by endovascular stent graft repair of the aneurysm. This procedure is most useful in cases with challenging anatomy to enable repair of the internal carotid artery aneurysm with minimal morbidity to the patient.

Submandibular TCD approach detects post-bulb ICA stenosis in children with sickle cell anemia

Transcranial Doppler (TCD) ultrasound is a procedure commonly used to screen individuals with the major hemoglobin S diseases, Hb SS and Hb S-beta(0), for significant stenoses in the circle of Willis. Flow velocities above 200 cm/s have been shown to identify patients at elevated risk for cerebral infarction. Among TCD's limitations is the inability to insonate the distal extracranial, petrous, and cavernous internal carotid artery (ICA) through the standard transtemporal approach. We extended the submandibular approach to include infra-siphon portions of the ICA. Using the extended submandibular approach to evaluate these portions of the ICA, we identified stenotic lesions in 4 patients with Hb SS disease out of a population of 131 children with Hb SS. Three of the 4 patients had no history of overt stroke or stroke-like symptoms. Neuroimaging confirmed the stenotic lesions, and also revealed watershed infarction as well as discrete areas of silent infarction. All 4 children had neuropsychological impairment. The submandibular approach, when added to a standard transcranial Doppler examination, may increase the sensitivity of this technique to identify important potential sources of cerebral infarction.

Urgent Endovascular Covered-Stent Treatment of Internal Carotid Artery Injury Caused by a Gunshot

Penetrating non-lethal injuries to the distal extra-cranial internal carotid artery are often a surgical challenge, because of the difficulty of direct exposure and repair of the internal carotid artery at the skull base. We describe a case of a successful emergency treatment, with an endovascular procedure using a PTFE covered-stent, of an internal carotid artery haemorrhagic pseudoaneurysm following penetrating trauma to the neck by single gunshot.

経口腔頚部血管超音波検査法（ｔｒａｎｓｏｒａｌ ｃａｒｏｔｉｄ ｕｌｔｒａｓｏｎｏｇｒａｐｈｙ，ＴＯＣＵ）の開発と応用

We developed transoral carotid ultrasonography, TOCU, which enabled us to evaluate the distal extracranial internal carotid artery (ICA) using the transoral method in 1998 and applied it to patients with carotid occlusive disease, moyamoya disease, or carotid arterial dissection. Examinations were performed using a color Doppler flow imaging system equipped with a stick-like convex array transducers (9-5 MHz). We inserted a transducer covered with thin gum transorally, touching the tip to the pharyngeal postero-lateral wall. We then attempted to detect the ICA and measure flow velocity of the distal extracranial ICA using principal images obtained by TOCU. In the healthy five volunteers, the ICA was identified at a depth of 2.2±0.6cm and visualized as a vertical linear vessel 2.9±0.3 cm in length and bent slightly backwards. The diameter and mean flow velocity of the distal extracranial ICA was 4.7±0.2mm and 50±7cm/sec, respectively. In the stroke patients, some remarkable findings were obtained, including a dilated ICA with narrow true lumen in a patient with ICA dissection, a lucent echo without flow signal in a patient with acute cardioembolic ICA occlusion, and decreased ICA diameter less than 3.0mm in a patient with pseudo-occlusion of the ICA or moyamoya disease. The TOCU is a helpful method as the procedure of compensating conventional carotid ultrasonography.

Transoral Carotid Ultrasonography for Evaluating Internal Carotid Artery Occlusion

Transoral carotid ultrasonography (TOCU) has enabled the assessment of the distal portion of the extracranial internal carotid artery (ICA). We evaluated the ultrasonographic features of ICA occlusion using TOCU. We studied 50 occluded ICAs in 42 stroke patients. The mechanism of ICA occlusion was embolic (group E) in 14 arteries and thrombotic (group T) in the other 36 arteries. We used a color flow imaging system equipped with special convex array transducers, and placed the probe on the postero-lateral pharyngeal wall to identify the distal extracranial ICA. We evaluated intraluminal echodensity (lucent or opaque) and measured the diameter of the ICA. Then, we examined the relationship of these early (<1 week after onset) and chronic (>4 weeks after onset) phase TOCU findings to the mechanism of ICA occlusion and the site of occlusion. In the early phase of a stroke, the intraluminal echodensity was more frequently lucent (9/11, 81.8%) in group E than in group T (5/20, 20%, p<0.05). In the chronic phase, echodensity became opaque in both groups. In the early phase, the lucent echodensity was more frequently seen in patients with distal occlusion than in those with proximal occlusion. Thus, it may represent blood or fresh thrombus formation. In patients with unilateral ICA occlusion, the occluded ICA was significantly smaller in diameter than the non-occluded contralateral artery both in the early and chronic phases. The echodensity and diameter of the extracranial ICA distal portion as found on TOCU can help to identify the mechanism of ICA occlusion.

頚動脈病変の超音波診断 経口腔頚部血管超音波検査

We introduced transoral carotid ultrasonography (TOCU) which enabled us to evaluate the distal extracranial internal carotid artery (ICA). Examinations were performed using a color Doppler flow imaging system equipped with a convex array stick-like transducers (9 - 5 MHz). We inserted the probe covered with thin gum transorally, touching the tip to the pharyngeal postero-lateral wall. Then we could obtain image and measure flow velocity of the distal portion of extracranial internal carotid artery.TOCU was successfully performed in healthy five volunteers without any difficulty. The ICA was identified at a depth of 2.2 ± 0.6cm and visualized as a vertical linear vessel about 3.0cm in length and bent slightly backwards. The diameter and mean flow velocity of the distal extracranial ICA was 4.7 ± 0.2mm and 50 ± 7 cm/sec, respectively.In acute stage of embolic ICA occlusion, TOCU frequently demonstrated echo lucent lumen at the distal extracranial ICA, while it seldom does in acute stage of atherothrombotic ICA occlusion or in chronic stage of ICA occlusion. Therefore, TOCU seems useful to distinguish mechanism of ICA occlusion in its acute stage.In internal carotid artery dissection, TOCU showed true and pseudo lumens or narrow lumens in the affected side. TOCU seems a useful technique to make up for conventional carotid ultrasonography.

Surgical Aspects of Fusiform and Saccular Extracranial Carotid Artery Aneurysms

The purpose of this paper is to analyse surgical aspects of aneurysms of the distal extracranial internal carotid artery. Nine cases of extracranial carotid artery aneurysm are reported. Five were fusiform, located at the carotid bifurcation, and four were saccular, confined to the internal carotid artery. An end-to-end plication technique and Dacron patch angioplasty were employed for all fusiform aneurysms. In three saccular lesions, resection and 4-mm polytetrafluoroethylene (PTFE) graft interposition were carried out. In one case with a high lesion, ligation of the carotid artery was performed. Ligation resulted in severe postoperative stroke and fatal outcome. One patient with a saccular lesion developed a transient ischaemic attack after the operation. In other patients no central neurological deficit was produced by the surgery itself. Transient cranial nerve damage occurred in four patients (two hypoglossal nerve; two superior laryngeal nerve). As demonstrated by these cases, synthetic material may be used in restoration of the carotid artery. It is concluded that, according to type, location of the aneurysm and adequacy of contralateral cerebral blood flow, selective management is necessary.

Surgical aspects of fusiform and saccular extracranial carotid artery aneurysms

The purpose of this paper is to analyse surgical aspects of aneurysms of the distal extracranial internal carotid artery. Nine cases of extracranial carotid artery aneurysm are reported. Five were fusiform, located at the carotid bifurcation, and four were saccular, confined to the internal carotid artery. An end-to-end plication technique and Dacron patch angioplasty were employed for all fusiform aneurysms. In three saccular lesions, resection and 4-mm polytetrafluoroethylene (PTFE) graft interposition were carried out. In one case with a high lesion, ligation of the carotid artery was performed. Ligation resulted in severe postoperative stroke and fatal outcome. One patient with a saccular lesion developed a transient ischaemic attack after the operation. In other patients no central neurological deficit was produced by the surgery itself. Transient cranial nerve damage occurred in four patients (two hypoglossal nerve; two superior laryngeal nerve). As demonstrated by these cases, synthetic material may be used in restoration of the carotid artery. It is concluded that, according to type, location of the aneurysm and adequacy of contralateral cerebral blood flow, selective management is necessary. © 1997 The International Society for Cardiovascular Surgery.

Side-to-side differences and day-to-day variations of transcranial Doppler parameters in normal subjects.

We investigated 35 normal adults to assess variations in cerebral artery blood velocities, hemispheric blood velocity ratios, and pulsatility indices, both with regard to changes between the sides and between days. We found no significant variations between sides or days. Changes from one day to the next exceeding 20% in blood velocity in the middle cerebral artery (VMCA), the anterior cerebral artery (VACA), the distal extracranial internal carotid artery (VICA), and in the hemispheric VMCA/VICA, VACA/VICA, or VACA/VMCA ratios, may be considered significant at the 95% level.

Effect of acetazolamide on cerebral artery blood velocity and regional cerebral blood flow in normal subjects.

The effect of intravenous acetazolamide 1 g on cerebral artery blood velocity and regional blood flow (rCBF) was investigated in eight normal subjects. Blood velocity was measured with 2 MHz pulsed Doppler in the proximal segments of the middle, anterior and posterior cerebral artery (MCA, ACA, and PCA) and in the distal extracranial internal carotid artery (ICA). The rCBF in the regions of interest tentatively corresponding to the perfusion territories of these vessels was estimated using 133Xe inhalation and a rapidly rotating single photon emission computer tomograph. Both blood velocity and rCBF increased after acetazolamide. There was no significant difference between the percentage ICA blood velocity increase (22 +/- 12%) and the percentage rCBF increase in the ICA region of interest (25 +/- 9%). In the MCA, ACA, and PCA, however, blood velocity increased more (mean increase 36-42%) than the rCBF in the corresponding regions of interest (mean increase 24-26%). These differences were highly significant suggesting a direct and site specific effect of acetazolamide in narrowing the lumen of the proximal MCA, ACA, and PCA, but not of the extracranial ICA. We also propose that the effect of acetazolamide induces reciprocal changes in the extent of adjacent perfusion territories in individual brain hemispheres. Data compiled from all subjects investigated at two very different perfusion levels (before and after acetazolamide) revealed a significant positive correlation between blood velocity and rCBF.

Blood velocity and regional blood flow in defined cerebral artery systems.

Cerebral artery blood velocity and regional blood flow (rCBF) were investigated in 17 normal subjects. Blood velocity was measured with 2 MHz pulsed Doppler ultrasound in the proximal segments of the middle, anterior and posterior cerebral artery (MCA, ACA, and PCA) and in the distal extracranial internal carotid artery (ICA). The rCBF in the regions of interest tentatively corresponding to the perfusion territories of these vessels was estimated using 133Xe inhalation and a rapidly rotating single photon emission computer tomograph. Concomitant capnograph recordings showed that the end-expiratory pCO2 was higher during the rCBF than during the blood velocity examinations. This differences was highly significant. While there was no significant correlation between blood velocity and rCBF when these clear differences in pCO2 were disregarded, we did find significant positive correlations when the data were normalized to a standard pCO2 (5.3 kPa) using accepted formulas. The best correlation was found for the MCA (r = 0.630, p less than 0.001) and the PCA (r = 0.73, p less than 0.001), with a lower correlation in the ACA (r = 0.49, p less than 0.01) and the ICA (r = 0.41, p less than 0.05). The estimated blood velocity (V) given rCBF = 0 was not significantly different from 0. The results support the validity of expressing the relationship between blood velocity (V) and rCBF in defined cerebral artery systems as: V = 1/60 (rCBF) T (A)-1, where A represents the area of the lumen of the vessel segment where the velocity is being measured, and T denotes the size of the brain region being perfused from this artery.

Surgical management of aneurysms of the distal extracranial internal carotid artery: Sundt TM, Pearson BW, Piepgras DG, Houser OW, Mokri B. J Neurosurg 1986; 64: 169-82

Surgical management of aneurysms of the distal extracranial internal carotid artery: Sundt TM, Pearson BW, Piepgras DG, Houser OW, Mokri B. J Neurosurg 1986; 64: 169-82