The amphibian carotid labyrinth: some anatomical and physiological relationships

1982 ◽  
Vol 60 (5) ◽  
pp. 1153-1160 ◽  
Author(s):  
Dan Toews ◽  
Graham Shelton ◽  
Robert Boutilier

The carotid labyrinth of 13 different amphibian species were examined using a vascular casting technique. Only Typhlonectes compressicauda, an apodan, and Necturus do not have a labyrinth although members of the lungless Plethodontidae have a very reduced labyrinth vascular network. Blood pressures recorded in the internal carotid, external carotid, and common carotid arteries of freely moving Bufo marinus and Rana catesbeiana show that the labyrinth does not affect a pressure change or have a pulse dampening effect on blood flowing to the head region. It is suggested that the labyrinth can stimulate a [Formula: see text] increase in the internal carotid artery in Bufo and Rana although the underlying mechanism remains unknown.

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 526.1-526
Author(s):  
L. Nacef ◽  
H. Riahi ◽  
Y. Mabrouk ◽  
H. Ferjani ◽  
K. Maatallah ◽  
...  

Background:Hypertension, diabetes, and dyslipidemia are traditional risk factors of cardiac events. Carotid ultrasonography is an available way to detect subclinical atherosclerosis.Objectives:This study aimed to compare the intima-media thickness in RA patients based on their personal cardiovascular (CV) history of hypertension (hypertension), diabetes, and dyslipidemia.Methods:The present study is a prospective study conducted on Tunisian RA patients in the rheumatology department of Mohamed Kassab University Hospital (March and December 2020). The characteristics of the patients and those of the disease were collected.The high-resolution B-mode carotid US measured the IMT, according to American Society of Echocardiography guidelines. The carotid bulb below its bifurcation and the internal and external carotid arteries were evaluated bilaterally with grayscale, spectral, and color Doppler ultrasonography using proprietary software for carotid artery measurements. IMT was measured using the two inner layers of the common carotid artery, and an increased IMT was defined as ≥0.9 mm. A Framingham score was calculated to predict the cardiovascular risk at 10-year.Results:Forty-seven patients were collected, 78.7% of whom were women. The mean age was 52.5 ±11.06 [32-76]. The rheumatoid factor (RF) was positive in 57.8% of cases, and anti-citrullinated peptide antibodies (ACPA) were positive in 62.2% of cases. RA was erosive in 81.6% of cases. Hypertension (hypertension) was present in 14.9% of patients, diabetes in 12.8% of patients, and dyslipidemia in 12.8% of patients. Nine patients were active smokers. The mean IMT in the left common carotid (LCC) was 0.069 ±0.015, in the left internal carotid (LIC) was 0.069 ±0.015, in the left external carotid (LEC) was 0.060 ±0.023. The mean IMT was 0.068 ±0.01 in the right common carotid (RCC), 0.062 ±0.02 in the right internal carotid (RIC), and 0.060 ±0.016 in the right external carotid (REC). The IMT was significantly higher in the left common carotid (LCC) in patients with hypertension (p=0.025). There was no significant difference in the other ultrasound sites (LIC, LEC, RCC, RIC, and REC) according to the presence or absence of hypertension. The IMT was also significantly increased in patients with diabetes at LCC (p=0.017) and RIC (p=0.025). There was no significant difference in the IMT at different ultrasound sites between patients with and without dyslipidemia.Conclusion:Hypertension was significantly associated with the increase in IMT at the LCC level in RA patients. Diabetes had an impact on IMT in LCC and RIC. However, dyslipidemia did not affect the IMT at the different ultrasound sites.References:[1]S. Gunter and al. Arterial wave reflection and subclinical atherosclerosis in rheumatoid arthritis. Clinical and Experimental Rheumatology 2018; 36: Clinical E.xperimental.[2]Aslan and al. Assessment of local carotid stiffness in seronegative and seropositive rheumatoid arthritis. SCANDINAVIAN CARDIOVASCULAR JOURNAL, 2017.[3]Martin I. Wah-Suarez and al, Carotid ultrasound findings in rheumatoid arthritis and control subjects: A case-control study. Int J Rheum Dis. 2018;1–7.[4]Gobbic C and al. Marcadores subclínicos de aterosclerosis y factores de riesgo cardiovascular en artritis temprana. Subclinical markers of atherosclerosis and cardiovascular risk factors in early arthritis marcadores subclínicos de aterosclerose e fatores de risco cardiovascular na artrite precoce.Disclosure of Interests:None declared


2008 ◽  
Vol 62 (suppl_5) ◽  
pp. ONS363-ONS370 ◽  
Author(s):  
Yusuf Izci ◽  
Roham Moftakhar ◽  
Mark Pyle ◽  
Mustafa K. Basşkaya

Abstract Objective: Access to the high cervical internal carotid artery (ICA) is technically challenging for the treatment of lesions in and around this region. The aims of this study were to analyze the efficacy of approaching the high cervical ICA through the retromandibular fossa and to compare preauricular and postauricular incisions. In addition, the relevant neural and vascular structures of this region are demonstrated in cadaveric dissections. Methods: The retromandibular fossa approach was performed in four arterial and venous latex-injected cadaveric heads and necks (eight sides) via preauricular and postauricular incisions. This approach included three steps: 1) sternocleidomastoid muscle dissection; 2) transparotid dissection; and 3) removal of the styloid apparatus and opening of the retromandibular fossa to expose the cervical ICA with the internal jugular vein along with Cranial Nerves X, XI, and XII. Results: The posterior belly of the digastric muscle and the styloid muscles were the main obstacles to reaching the high cervical ICA. The high cervical ICA was successfully exposed through the retromandibular fossa in all specimens. In all specimens, the cervical ICA exhibited an S-shaped curve in the retromandibular fossa. The external carotid artery was located more superficially than the ICA in all specimens. The average length of the ICA in the retromandibular fossa was 6.8 cm. Conclusion: The entire cervical ICA can be exposed via the retromandibular fossa approach without neural and vascular injury by use of meticulous dissection and good anatomic knowledge. Mandibulotomy is not necessary for adequate visualization of the high cervical ICA.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1117.3-1118
Author(s):  
L. Nacef ◽  
H. Ferjani ◽  
H. Riahi ◽  
K. Maatallah ◽  
Y. Mabrouk ◽  
...  

Background:Rheumatoid arthritis (RA) is chronic inflammatory rheumatism characterized by an independent cardiovascular (CV) risk. The screening of carotid intima-media thickness (IMT) in the common carotid artery appears to be a marker of atherosclerosis and is used as a specific tool for CV risk assessment.Objectives:The main of this study was to determine the most associated US sites with CV risk in RA.Methods:The present study is a prospective study conducted on Tunisian RA patients in rheumatology department of Mohamed Kassab University Hospital (March and December 2020). The characteristics of the patients and those of the disease were collected. The measurement of cIMTwas done using high-resolution B-mode carotid US with a Philips machine with the patient in supine position, according to AmericanSociety of Echocardiography guidelines.The carotid bulb below itsbifurcation and the internal and external carotid arteries were evaluated bilaterally with gray scale, spectral and color Doppler ultra-sonography using proprietary software for carotid arterymeasurements.IMT was measured using the two inner layers of the commoncarotid artery and an increased IMT was defined as ≥0.9 mm. The CV risk at 10 years was calculated by the SCORE index.Results:Forty-seven patients were collected, of which 78.7% were women. The mean age was 52.5 ±11.06 years. The rheumatoid factor (RF) was positive in 57.8% of cases, and anti-citrullinated peptide antibodies (ACPA) were positive in 62.2% of cases. RA was erosive in 81.6% of cases. Hypertension (hypertension) was present in 14.9% of patients and diabetes in 12.8% of patients. Nine patients were active smokers. The mean IMT in the left common carotid (LCC) was 0.069 ±0.015, in the left internal carotid (LIC) was 0.069 ±0.015, in the left external carotid (LEC) was 0.060 ±0.023. The mean IMT was 0.068 ±0.01 in the right common carotid (RCC), 0.062 ±0.02 in the right internal carotid (RIC), and 0.060 ±0.016 in the right external carotid (REC). The mean SCORE index of CV risk was 2±2.81 [0-11.6]. CV risk was significantly associated with the IMTs for LIC (p=0.029; r=0.374), LEC (p=0.04; r=0.480), and REC (p=0.016; r=0.408). No association was found between the IMT in the LCC (p=0,361; r=0,162), neither in the RCC (p=0,438; r=0,140) nor the RIC (p=0,670; r=0,077).Conclusion:In our study, IMT is strongly associated with score index, especially in carotid bifurcation. However, IMT measured in common carotid does not reflect a cardiovascular risk at 10-years.References:[1]S. Gunter and al. Arterial wave reflection and subclinical atherosclerosis in rheumatoid arthritis. Clinical and Experimental Rheumatology 2018; 36: Clinical E.xperimental.[2]Aslan and al. Assessment of local carotid stiffness in seronegative and seropositive rheumatoid arthritis. SCANDINAVIAN CARDIOVASCULAR JOURNAL, 2017.[3]Martin I. Wah-Suarez and al, Carotid ultrasound findings in rheumatoid arthritis and control subjects: A case-control study. Int J Rheum Dis. 2018;1–7.Disclosure of Interests:None declared


Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Farid Khasiyev ◽  
Tatjana Rundek ◽  
Chensy Marquez ◽  
Clinton B. Wright ◽  
Ralph Sacco ◽  
...  

Background: Cervical internal carotid artery (ICA) tortuosity has been associated with vascular risk and stroke as well as genetic disorders related to abnormal extracellular matrix remodeling. It is plausible that dystrophic or aberrant arterial remodeling may therefore relate to cervical ICA tortuosity. We hypothesized that cervical ICA tortuosity relates to carotid dilatation, but not to traditional ultrasound (US) markers of atherosclerosis. Methods: Subjects of the NOMAS with available time-of-flight MRA were included in our study. Cervical ICA tortuosity was defined as a bend in the distal cervical ICA of > 90° as seen on MRA. We excluded subjects with < 5 cm of the cervical ICA visualized. Distensibility was calculated as the percentage excursion of the right CCA diastolic diameter during systole, which was assessed by high-resolution B-mode US of the right common carotid artery (CCA). We used multivariable logistic regression analyses to estimate odds ratios for the association of cervical ICA tortuosity and Doppler measures of carotid wall aging. Results: We visualized cervical ICA tortuosity in 468 NOMAS participants (mean age 64±8 years, 70% women, 70% Hispanic). It was present in 23% of subjects. In unadjusted models, cervical ICA tortuosity was more common in women (OR 2.34, 95% CI 1.34-4.11), Hispanics (OR 1.85, 95%CI 1.06-3.25) and those with higher diastolic blood pressures (OR per mm Hg 1.04, 95%CI 1.01-1.06), and less common among smokers (OR 0.23, 95%CI 0.07-0.78). In models adjusted for demographic and vascular risks, right CCA tortuosity was associated with ipsilateral larger CCA DD (OR 1.42, 95%CI 1.02-1.96) and borderline associated with lower distensibility (OR 0.94, 95%CI 0.87-1.01, P=0.06) but not with ipsilateral ICA IMT (OR 0.26, 95%CI 0.14-4.77), number of plaques (OR 1.08, 95%CI 0.76-1.53), maximum plaque thickness (OR 0.96, 95%CI 0.73-1.27), or plaque area (1.00, 95%CI 0.97-1.05). Conclusions: Cervical ICA tortuosity associates with ipsilateral cervical ICA dilatation and lower distensibility, but not with traditional US markers of atherosclerosis. The association with diastolic blood pressure suggests a role of steady, rather than pulsatile, hemodynamics in aberrant cervical ICA remodeling.


2014 ◽  
Vol 65 (4) ◽  
pp. 352-359 ◽  
Author(s):  
Santanu Chakraborty ◽  
Reem A. Adas

Purpose Neurologic determination of death or brain death is primarily a clinical diagnosis. This must respect all guarantees required by law and should be determined early to avoid unnecessary treatment and allow organ harvesting for transplantation. Ancillary testing is used in situations in which clinical assessment is impossible or confounded by other factors. Our purpose is to determine the utility of dynamic computed tomographic angiography (dCTA) as an ancillary test for diagnosis of brain death. Materials and Methods We retrospectively reviewed 13 consecutive patients with suspected brain death in the intensive care unit who had dCTA. Contrast appearance timings recorded from the dCTA data were compared to findings from 15 controls selected from patients who presented with symptoms of acute stroke but showed no stroke in follow-up imaging. Results The dCTA allows us to reliably assess cerebral blood flow and to record time of individual cerebral vessels opacification. It also helps us to assess the intracranial flow qualitatively against the flow in extracranial vessels as a reference. We compared the time difference between enhancement of the external and internal carotid arteries and branches. In all patients who were brain dead, internal carotid artery enhancement was delayed, which occurred after external carotid artery branches were opacified. Conclusion In patients with suspected brain death, dCTA reliably demonstrated the lack of cerebral blood flow, with extracranial circulation as an internal reference. Our initial results suggest that inversion of time of contrast appearance between internal carotid artery and external carotid artery branches at the skull base could predict a lack of distal intracranial flow.


Neurosurgery ◽  
2017 ◽  
Vol 80 (2) ◽  
pp. 235-247 ◽  
Author(s):  
Christopher M. Owen ◽  
Nicola Montemurro ◽  
Michael T. Lawton

Abstract BACKGROUND: Blister aneurysms of the supraclinoid internal carotid artery (ICA) are challenging lesions with high intraoperative rupture rates and significant morbidity. An optimal treatment strategy for these aneurysms has not been established. OBJECTIVE: To analyze treatment strategy, operative techniques, and outcomes in a consecutive 17-year series of ICA blister aneurysms treated microsurgically. METHODS: Seventeen patients underwent blister aneurysm treatment with direct clipping, bypass and trapping, or clip-reinforced wrapping. RESULTS: Twelve aneurysms (71%) were treated with direct surgical clipping. Three patients required bypass: 1 superficial temporal artery to middle cerebral artery bypass, 1 external carotid artery to middle cerebral artery bypass, and 1 ICA to middle cerebral artery bypass. One patient was treated with clip-reinforced wrapping. Initial treatment strategy was enacted 71% of the time. Intraoperative rupture occurred in 7 patients (41%), doubling the rate of a poor outcome (57% vs 30% for patients with and without intraoperative rupture, respectively). Severe vasospasm developed in 9 of 16 patients (56%). Twelve patients (65%) were improved or unchanged after treatment, and 10 patients (59%) had good outcomes (modified Rankin Scale scores of 1 or 2). CONCLUSION: ICA blister aneurysms can be cautiously explored and treated with direct clipping as the first-line technique in the majority of cases. Complete trapping of the parent artery with temporary clips and placing permanent clip blades along normal arterial walls enables clipping that avoids intraoperative aneurysm rupture. Trapping/bypass is used as the second-line treatment, maintaining a low threshold for bypass with extensive or friable pathology of the carotid wall and in patients with incomplete circles of Willis.


2018 ◽  
Vol 25 (2) ◽  
pp. 212-218
Author(s):  
Ryuichiro Kajikawa ◽  
Toshiyuki Fujinaka ◽  
Hajime Nakamura ◽  
Manabu Kinoshita ◽  
Takeo Nishida ◽  
...  

Background and purpose We report the outcomes of carotid artery stenting for patients with angiographically visible occipital artery–vertebral artery anastomosis. Methods Among 47 consecutive patients who underwent carotid artery stenting from January 2007 to December 2010, seven patients for whom cerebral angiograms clearly showed occipital artery–vertebral artery anastomosis were selected. Four different protection methods were used: distal internal carotid artery protection; carotid flow reversal; seatbelt and airbag technique; and double protection method of protecting both the external and internal carotid artery. Results One patient with distal internal carotid artery protection showed a high-intensity lesion at the border of the upper thalamus, internal capsule and lateral ventricle wall after carotid artery stenting. The other patient with the double protection method did not show any high-intensity lesions on postoperative diffusion-weighted imaging in the vertebrobasilar territory. All seven patients with visible occipital artery–vertebral artery anastomosis showed ipsilateral vertebral artery severe stenosis or occlusion. Conclusion Large occipital artery–vertebral artery anastomosis may be a pathway for embolic materials during carotid artery stenting. External carotid artery protection is recommended for carotid artery stenting in such patients.


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