Effect of ligation on internal carotid artery blood pressure in horses

The effect of a single ligature on back pressure in the internal carotid artery was studied in nine horses. In six anesthetized horses, one internal carotid artery was catheterized 2 cm from its origin and blood pressure was recorded continuously. Then the artery was ligated, pressure was recorded again, and the horses were euthanatized. In another three anesthetized horses, indwelling catheters were placed in both internal carotid arteries and a loose ligature was placed proximal to one catheter. After horses recovered from anesthesia, the ligature was tied and blood pressure was recorded in both arteries on that day and 3 days later, then these horses were euthanatized. The anatomy of the cerebral arteries was examined in all nine horses. Blood pressure in the internal carotid arteries did not change after ligation. Subjectively, collateral channels considered most likely to maintain blood pressure in the ligated internal carotid artery were the caudal intercarotid artery and the cerebral arterial circle. We concluded that ligation of the internal carotid artery would not prevent severe hemorrhage from the internal carotid artery in horses with guttural pouch mycosis until the ligated artery thrombosed to the level of the lesion.     

Combined intraoperative retrograde stent implantation and thrombendarterectomy of the carotid artery

HISTORY AND CLINICAL FINDINGS: A 63-year-old man developed recurrent transitory ischaemic episodes of vertigo and weakness in the legs 6 weeks before admission. 3 weeks later he had a left amaurosis fugax. A stenotic murmur was heard over the left carotid artery. INVESTIGATION: Intraarterial digital subtraction angiography of the arteries to the head revealed occlusion of the right internal carotid artery (RICA) and marked narrowing at the origin of the left common carotid artery (LCCA), which could not be passed by catheter. TREATMENT AND COURSE: As a catheter could not be passed into the LCCA, a stent was at operation placed retrogradely into it. Intraoperative angiography showed subtotal stenosis of the left ICA, which was treated by thrombendarterectomy and dacron patch-plasty. The postoperative course was without complication and the patient was free of symptoms. Follow-up angiography was unremarkable. CONCLUSION: If a stenosis of the carotid artery cannot be passed by catheter, intraoperative retrograde placement of a stent is an alternative to percutaneous antegrade transluminal angioplasty or surgical bypass.     

Paradoxical cerebral embolism during fibrinolysis therapy in deep vein thrombosis and pulmonary embolism

A 37-year-old woman with increasing dyspnoea over several months suddenly developed severe ortho- and tachypnoea as well as cyanosis of the lips and acrocyanosis. Pulmonary angiography revealed massive bilateral pulmonary emboli with a systolic pulmonary artery pressure of 75 mm Hg. Phlebography demonstrated a thrombotic occlusion of the deep veins of the left leg extending to the distal femoral vein. Thrombolysis treatment was started via an indwelling pulmonary artery catheter (500,000 IU urokinase and 10,000 IU heparin as bolus, then 1 mill. IU urokinase and 1,000 IU heparin per hour). After two hours an incomplete left-sided paresis occurred (involving ocular and facial muscles, dysarthria, left arm and left leg) and the thrombolytic infusion was stopped. But cerebral computed tomography (CT) did not demonstrate any intracerebral haemorrhage. The heparin infusion was restarted (partial thromboplastin time between 70 and 90 s). CT examinations during the next few days showed the development of an ischaemic infarction in the distribution of the right medial cerebral artery. Angiography demonstrated occlusion of the right internal carotid artery. The diagnosis of a paradoxical embolus was supported by easy cardiac catheter passage through a patent foramen ovale. Subsequent pulmonary angiography demonstrated a thrombus-free pulmonary arterial circulation with a normal pulmonary arterial pressure. There was gradual and extensive regression of the incomplete hemiparesis.     

Lamotrigine toxicity secondary to sertraline

Branches of the extracranial internal carotid artery are very rare. A case is reported wherein an aberrant artery originated from the bulb of the internal carotid artery (ICA) approximately 2 cm from the bifurcation. The ICA was occluded distal to the branch's origin. Arteriography in this case gave the appearance of a carotid "string sign". Vascular surgeons and radiologists should be aware of this anomaly when interpreting carotid arteriograms.     

Internal carotid artery occlusion related to seat belt shoulder strap: report of two cases

Two cases of traumatic internal carotid artery occlusion probably related to the seat belt shoulder strap are reported. Case 1. A 20-year-old woman was driving and was struck on the right front side of her car by another car. There were neither bruises, abrasions on her neck, nor weakness in her extremities. About 4 hours later, she developed left hemiplegia, and CT scan taken on the following day revealed low density areas in the capsulostriatal area on the right. The right carotid angiography revealed occlusion of the internal carotid artery about 3 cm distal to the bifurcation. Case 2. A 43-year-old man was driving and was struck on the front of his car by a hard iron railing. He sustained a sternum fracture, but there was no disturbance of consciousness or paresis of the extremities. His neck was unremarkable externally. About 50 days later, he developed left hemiplegia. CT scan and MRI revealed a massive infarction in the distribution of the right middle cerebral artery territories. The carotid angiography revealed occlusion of the right internal carotid artery about 3 cm distal to the bifurcation. In each cases, the driver was wearing a three-point shoulder seatbelt when the car was struck on the front or on the right front. Previous experimental studies have revealed in these situations the neck is flexed right anteriorly, and then quickly overextended left posteriorly. The overextension of the neck probably injured the intima of the internal carotid artery ipsilateral to the shoulder fixed in the seatbelt, resulting in the subsequent occlusion by a thrombus.     

Duplication of the extracranial internal carotid artery

We describe a case of duplication of the left internal carotid artery from a point 1 cm distal to the origin to the proximal petrous segment where the vessel reunites. Duplication and fenestration of the internal carotid artery are discussed. A review of embryologic development is presented. Identification of these entities is important, especially in patients who require surgical intervention involving the internal carotid artery.     

An experience of the modified Norwood's operation for hypoplastic left heart syndrome with aberrant origin of right subclavian artery and persistent left superior vena cava--the procedure without total circulatory arrest and cardiac arrest

We reported a successful case of the modified Norwood operation for a 21-day-old neonate with hypoplastic left heart syndrome (MS and AS) associated with an aberrant right subclavian artery and a persistent left superior vena cava. The modified Norwood operation was performed without total circulatory arrest and Cardiac arrest. A 4 mm Gore-Tex graft, which was anastomosed between the right carotid artery and the right pulmonary artery for systemic-pulmonary shunt, was used for cerebral perfusion during aortic arch reconstruction. Coronary perfusion was performed with a small cannula placed on the relatively large ascending aorta during anastomosis between the main pulmonary artery and the ascending aorta. Equine pericardial patch was used for aortic arch reconstruction and the ascending aorta was directly anastomosed to a part of the main PA. Postoperative course was uneventful and postoperative MRI revealed no stenosis of the aortic arch and the pulmonary artery.     

Mycotic aneurysm of the external carotid artery

Mycotic aneurysms of the extracranial carotid arteries are extremely rare. A case is reported of a false aneurysm of the left external carotid artery. This developed secondary to cervical lymphadenitis which did not settle with high dose antibiotic therapy. The diagnosis was made on investigation with carotid doppler ultrasound and confirmed with computerized tomography. Digital subtraction angiography was performed to highlight the vascular anatomy. In addition percutaneous balloon catheter control of blood flow in the external carotid artery was used as an adjunct to surgical management.     

Circulatory arrest with profound hypothermia during the surgical treatment of large internal carotid artery aneurysm--case report

A 43-year-old male presented with a cerebral aneurysm manifesting as right facial paresthesia, without neurological deficit. Angiography revealed a large aneurysm (22 mm) of the left internal carotid artery. Intravascular treatment using placement of a detachable coil was attempted, but the coil did not stay in the aneurysmal cavity and the procedure was abandoned. The patient did not tolerate the transient balloon occlusion test of the left internal carotid artery. Therefore, the aneurysm was clipped through an open craniotomy with profound hypothermia (20 degrees C) with cardiac arrest (24 minutes). The aneurysmal dome was collapsed, allowing easy dissection of the posterior communicating artery. The closed chest method was used during the extracorporeal cardiopulmonary bypass. Postoperative angiography revealed complete neck clipping with preservation of carotid blood flow. The patient recovered well and resumed his employment. Circulatory arrest with hypothermia provides several benefits for the surgical treatment of large and giant aneurysms.     

Accuracy of duplex ultrasound in evaluating carotid artery anatomy before endarterectomy

PURPOSE: Anatomic features, such as a high carotid bifurcation (< 1.5 cm from the angle of the mandible), excessive distal extent of plaque (> 2.0 cm above the carotid bifurcation), or a small diameter (< or = 0.5 cm) redundant or kinked internal carotid artery can complicate carotid endarterectomy. In the past, arteriography was the only preoperative study capable of imaging these features. This study assessed the ability of duplex ultrasound to evaluate their presence before surgery. METHODS: A consecutive series of 20 patients who underwent 21 carotid endarterectomies had preoperative duplex ultrasound evaluations of these anatomic features. These evaluations were correlated with operative measurements from an observer blinded to the duplex findings. RESULTS: The mean difference between duplex and operative measurements for the distance between the carotid bifurcation and the angle of the mandible, the distal extent of plaque, and the internal carotid artery diameter was 0.9 cm, 0.3 cm, and 0.8 mm, respectively. The correlation coefficient between the two methods was 0.86, 0.75, and 0.59, respectively. Duplex ultrasound predicted a high carotid bifurcation, excessive distal extent of plaque, or a redundant or kinked internal carotid artery with 100% sensitivity (p < 0.05, p < 0.01, and p < 0.001, respectively). The sensitivity of duplex ultrasound in predicting a small internal carotid artery diameter was 80%. The specificity of duplex ultrasound for predicting excessive distal extent of plaque, small internal carotid artery diameter, high carotid bifurcation, and a coiled or kinked carotid artery was 92%, 56%, 100%, and 100%, respectively. CONCLUSION: Duplex ultrasound can predict the presence of anatomic features that may complicate carotid endarterectomy. Preoperative duplex imaging of these features may be helpful in patients who undergo carotid endarterectomy without preoperative arteriography.     

Endoluminal repair of internal carotid artery aneurysm: a feasible but hazardous procedure

PURPOSE: The aim of this study was to report the repair of an aneurysm of the internal carotid artery using the endoluminal method. METHODS: A 70-year-old male patient noted a swelling in the right side of his neck 22 years after endarterectomy of the right internal carotid artery. Duplex ultrasound confirmed the clinical diagnosis of aneurysm of the internal carotid artery. Further investigation included contrast-enhanced computed tomographic (CT) scanning and carotid angiography performed via a retrograde femoral approach. The aneurysm contained thrombus and was 3 cm in diameter and in length. It extended superiorly from a point 0.5 cm above the carotid bifurcation to a point estimated to be 2 cm from the base of the skull. Repair of the aneurysm was undertaken using the endoluminal method. A self-expanding endograft 8 mm in diameter and 4 cm in length was introduced through a 12F sheath in the common carotid artery. An on-table completion angiogram of the right-sided extracranial carotid arteries and the intracranial internal carotid artery and branches was obtained. RESULTS: The completion angiogram and postoperative CT scan confirmed exclusion of the aneurysm sac from the circulation. The patient awoke from anesthesia with complete paralysis of the left arm. Recovery of movement commenced 1 hour later. A brain CT scan demonstrated the event to be an embolic stroke. Strength had returned by 7 days. Function of the arm was good 1 month after operation, but coordination for fine movements was lacking. At the 6-month follow-up, good arm function was maintained. A duplex ultrasound scan demonstrated not only continued exclusion of the aneurysm sac but occlusion of the endograft, also. CONCLUSIONS: Endoluminal repair of aneurysms of the internal carotid artery is feasible but carries the risk of major morbidity as a result of peripheral embolization and early occlusion of the endograft.     

Refusion of anterior cerebral artery after aneurysm clipping--a case report

Herein, we are describing an unusual case suffering from a left anterior cerebral artery aneurysm (A1). Both the anterior cerebral arteries were supplied by the left internal carotid artery as was found in digital substraction angiography (DSA) preoperatively. The postoperative angiograms revealed that left anterior cerebral artery was supplied from the left internal carotid artery and the right anterior cerebral artery by the right internal carotid artery respectively. This finding of cerebral angiograms is interesting and rarely mentioned in the literature. Its hemodynamic change and pathogenesis were unclear and different to that of the coronary circulation, ischemic change of gut and skeletal muscle. The causes may include: 1) vasospasm at the anterior communicating artery after manipulation at surgery; 2) desiccation or shrivelling the adjacent artery by intraoperative electrocoagulation; 3) occlusion the anterior communicating artery by the wing of clip. 4) the deprivation of the blood flow from the left internal carotid artery after totally or partially narrowing left A1 by an aneurysm clip. The redistribution of blood volume in the previously hypoplastic right anterior cerebral artery and decreased caliber of the left anterior cerebral artery (A1) are likely playing a role in this case.     

Radiation exposure of the population by roentgen diagnosis. II. The collective effective dosage of the population in former East Germany caused by 1987/1988 roentgen diagnosis

OBJECTIVES: To examine the relations between the development of neurologic events and the following variables: degree of stenosis of the contralateral carotid artery, prior neurologic symptoms and stump pressure of the ipsilateral internal carotid artery in patients undergoing carotid endarterectomy under regional anesthesia. PATIENTS AND METHODS: We undertook a prospective study of 92 patients undergoing carotid endarterectomy with a blockade of the superficial and deep cervical plexus. Neurological integrity was assessed and internal carotid artery stump pressure was monitored. Contralateral carotid artery stenosis and neurologic disease present before surgery were studied. RESULTS: Neurologic events developed when the carotid artery was clamped in 9.7% of patients. Mean stump pressure was significantly lower in symptomatic patients (43 +/- 11 mmHg) than in asymptomatic patients (74.6 +/- 24 mmHg) (p < 0.001). Neurologic symptoms developed during clamping of the carotid in 27.2% of the patients with stump pressure less than or equal to 50 mmHg, but in only 4.2% of those with stump pressure surpassing 50 mmHg. Stump pressure was significantly lower in patients with contralateral carotid stenosis. The incidence of neurologic events during clamping was unrelated to contralateral carotid condition, however. Likewise, neurologic symptoms before surgery was also unrelated. In six of the nine patients with neurologic events, internal carotid stump pressure was less than or equal to 50 mmHg, indicating that the sensitivity of this parameter to the development of neurologic events in our series was 66%. CONCLUSIONS: Although internal carotid artery stump pressure identifies a subset of patients likely to have a higher incidence of neurologic events during carotid artery clamping, it can not be considered the only criterion for placement of an intraluminal shunt to prevent such events. The state of the contralateral carotid artery and preexisting neurologic symptoms are not objective screening criteria for identifying patients at high risk of neurologic events during carotid clamping.     

Moyamoya disease associated with pulmonary sarcoidosis--case report

A 61-year-old female presented with a unique case of moyamoya disease associated with pulmonary sarcoidosis. She was admitted for sudden onset of left temporalgia with episode of numbness on face, tongue, and upper extremity on the right side. The next morning, she had symptoms of Gerstmann syndrome and her ability to speak was disturbed. Her medical history included radical resection of lung cancer on the right side. She had no symptoms of pulmonary sarcoidosis. Neuroimaging showed an infarction in the left occipital lobe. Angiography showed occlusions of the bilateral internal carotid arteries at the supraclinoid portions. Subsequently, a left superficial temporal artery-middle cerebral artery anastomosis with encephalo-myo-synangiosis was performed. Ninety-three days after admission, she suddenly developed dyspnea which resulted in death 3 hours later. Autopsy findings showed typical epithelioid granulomas of sarcoid type in the lymph nodes of the peribronchus, lung, and liver. Thrombotic emboli were found in the bilateral pulmonary arteries, and marked fibrous intimal thickening in the bilateral internal carotid arteries. Immunological reaction with inflammatory events may cause pathological changes in patients with moyamoya disease or sarcoidosis. The co-incidence in this case suggests that some common inflammatory events may be involved in the pathogenesis of these diseases.     

Bilateral caudate head infarcts

We reported a 67-year-old woman with bilateral caudate head infarcts. She developed sudden mutism followed by abulia. She was admitted to our hospital 2 months after ictus for further examination. She showed prominent abulia and was inactive, slow and apathetic. Spontaneous activity and speech, immediate response to queries, spontaneous word recall and attention and persistence to complex programs were disturbed. Apparent motor disturbance, gait disturbance, motor aphasia, apraxia and remote memory disturbance were not identified. She seemed to be depressed but not sad. Brain CT and MRI revealed bilateral caudate head hemorrhagic infarcts including bilateral anterior internal capsules, in which the left lesion was more extensive than right one and involved the part of the left putamen. These infarct locations were thought to be supplied by the area around the medial striate artery including Heubner's arteries and the A1 perforator. Digital subtraction angiography showed asymptomatic right internal carotid artery occlusion. She bad had hypertension, diabetes mellitus and atrial fibrillation and also had a left atrium with a large diameter. The infarcts were thought to be caused by cardioembolic occlusion to the distal portion of the left internal carotid artery. Although some variations of vasculature at the anterior communicating artery might contribute to bilateral medial striate artery infarcts, we could not demonstrate such abnormalities by angiography. Bilateral caudate head infarcts involving the anterior internal capsule may cause prominent abulia. The patient did not improve by drug and rehabilitation therapy and died suddenly a year after discharge.     

Device to limit inflation of a pulmonary artery catheter balloon

OBJECTIVE: The most serious complication seen with pulmonary artery catheters is rupture of the pulmonary artery. The effectiveness of an external safety balloon added to the pulmonary artery balloon inflation port was tested. DESIGN: The external balloon is designed to inflate and absorb excess volume from the inflation syringe after the internal balloon contacts the vessel wall. When the catheter tip is in a small pulmonary artery, expansion of the external balloon indicates that the catheter tip is in a noncompliant or small vessel. SETTING: The external balloon was tested in a bench simulation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The pulmonary artery balloon was slowly inflated inside 2.6-, 3.0-, 4.7-, 8.6-, and 11.6-mm internal diameter polyvinyl chloride tubes, with and without the external safety device in place. Without the external balloon, the average balloon pressure was 1647 +/- 145 (SD) mm Hg in the 2.6-mm vessel. With the external balloon in use, the maximum pulmonary artery balloon pressure was 473 +/- 7.2 mm Hg in the 2.6-mm vessel. CONCLUSIONS: The external balloon can limit balloon pressures within the pulmonary artery and identify when excessive volumes are being forced into the pulmonary artery balloon.     

Agenesis of the internal carotid artery associated with an aneurysm of the anterior communicating artery

We report a case of agenesis of the internal carotid artery which was revealed by a subarachnoid hemorrhage. Angiography showed a ruptured aneurysm of the anterior communicating artery and unilateral absence of the left internal carotid artery. Both the left anterior and middle cerebral arteries were perfused from the right carotid artery via the anterior communicating artery. Absence of the left carotid canal was proved on bone CT. Such an association is discussed. An hemodynamic stress on a congenital defect of the cerebral arterial wall could be the origin of the aneurysm development.     

Pattern shift visual evoked response in carotid occlusion

Pattern shift visual evoked response (PSVER) latency has been shown to be an extremely sensitive but nonspecific measure of optic nerve dysfunction. The test has been most useful in detecting unsuspected demyelinating lesions of the optic nerve, but abnormal results have been reported in a variety of other conditions affecting the optic nerve, including ischemic optic neuropathy. We report a patient with left internal carotid artery occlusion, possibly secondary to neck trauma, with normal ophthalmological examination and abnormal PSVER. The suggested mechanism is subclinical optic nerve ischemia due to decreased blood flow in the ophthalmic artery. PSVER may have value as a sensitive indicator of internal carotid artery disease.     

Thrombotic, infectious, and procedural complications of the jugular bulb catheter in the intensive care unit

OBJECTIVE: An assessment of the thrombotic, infectious, and technical complications of continuous jugular bulb catheter monitoring in the intensive care unit (ICU) was made. METHODS: Over a 1-year period, 44 patients suffering from traumatic brain injury, subarachnoid hemorrhage, or stroke received jugular bulb catheter monitoring in the ICU. They were followed for catheter insertion complications and the development of bacteremia. In 20 patients chosen randomly, an ultrasonographic evaluation was performed after removal of the catheter for an assessment of internal jugular vein thrombosis. RESULTS: Of the 44 patients, 1 became bacteremic; the source was identified as a thoracostomy site. Among the complications related to the 44 catheter insertions, there were 2 instances of carotid artery puncture (4.5%), 1 misplaced catheter (thoracic placement), and 1 clinically insignificant hematoma. Of the 20 patients investigated with ultrasonography, 8 (40%) had nonobstructive, subclinical internal jugular vein thrombi after jugular bulb catheter monitoring (95% confidence interval, 19-61%). The median monitoring duration was 3 days (range, 1-6 d). No clinical factor was identified to be associated with thrombus formation. CONCLUSION: We conclude the following: 1) the risk of bacteremia related to the jugular bulb catheter was negligible; 2) complications related to catheter insertion were rare and clinically insignificant; and 3) the incidence of subclinical internal jugular vein thrombosis after jugular bulb catheter monitoring is considerable. Although it is worthy to note this complication, no patient with a thrombus became symptomatic in the present series. The risk-benefit assessment of this monitoring technique must include consideration of subclinical thrombosis.     

Diagnosis of disease of the common carotid artery bifurcation: CT angiography vs catheter angiography

OBJECTIVE: The purpose of this prospective study was to compare CT angiography with conventional catheter angiography for imaging the bifurcation of the common carotid artery in patients with signs and symptoms of atherosclerotic disease. SUBJECTS AND METHODS: Ten symptomatic patients (20 bifurcations of the common carotid artery) underwent contrast-enhanced spiral CT of the neck. The images were preprocessed and postprocessed by using a commercially available volume-rendering technique and a maximum-intensity-projection algorithm. All patients subsequently underwent conventional catheter angiography. RESULTS: CT angiographic findings matched those on conventional angiograms in only 50% of cases. Two nearly occluded internal carotid arteries were missed with CT angiography. Four internal carotid arteries were interpreted as occluded on the basis of CT angiograms but were shown as patent on catheter angiograms. Of five severe stenoses shown by CT angiography, only two were confirmed by conventional angiography. CONCLUSION: The results indicate that CT angiography as used in this study cannot replace catheter angiography. With CT angiography, both overestimation and underestimation of stenoses occur.