Bilateral Internal Carotid Artery Occlusion Associated with the Antiphospholipid Antibody Syndrome
A 39-year-old woman was transferred to our hospital after being found unconscious at home. She was confused, but was able to give a history of left-sided weakness with decreased use of her left hand and difficulty bearing weight on her left leg that had begun abruptly 3 days prior to presentation.\nShe had had one prior outside hospital admission 1 year earlier for a left middle cerebral artery stroke that presented with expressive aphasia and right arm and leg weakness. Limited MRI at that time revealed 2 areas of restricted diffusion in the left parietal lobe with increased FLAIR signal and associated cortical/subcortical enhancement. Axial T1-weighted images showed the absence of a flow void in the left internal carotid artery, while the right internal carotid artery appeared patent based on the presence of a normal flow void. Imaging showed no evidence of dissection. The patient underwent stereotactic biopsy of the left parietal lesion to rule out a neoplasm. The results showed nonspecific necrotic changes and no evidence of a neoplasm. She was discharged to inpatient rehabilitation, and over the subsequent months her speech and motor function completely recovered.\nThree years prior to her current presentation, the patient had had a miscarriage at 12 weeks’ gestation. Her history was also significant for intravenous methamphetamine use, ending 13 years prior to presentation, and an 18 pack-year smoking history. She had no history of head or neck trauma. She did not have hypertension, diabetes, or hyperlipidemia. She did not use birth control pills and did not have a history of deep venous thrombosis or pulmonary embolism. Her family history was remarkable for systemic lupus erythematosus in her father and a brother who was diagnosed with thrombotic thrombocytopenia purpura.\nOn examination, her blood pressure was 126/80 mm Hg, and her heart rate was 91 beats/min and regular. There was no cardiac murmur. She was alert and oriented to person, but not place, time, or situation. She was able to follow simple commands, but was slow to respond. Her speech was fluent, with intact repetition and naming and without aphasia or dysarthria. Cranial nerve examination was significant for a left homonymous hemianopsia and left lower facial weakness. Her motor exam revealed left hemiparesis, left hyperreflexia, and a left Babinski sign. She had intact sensation of light touch bilaterally, but extinction on the left with double simultaneous stimuli. Movements were slow on the left side, but there was no ataxia. Gait was not assessed.\nAbnormal coagulation studies included a prolonged activated partial thromboplastin time at 42.6 s (normal range 25.1–37.6 s) which did not correct with a 1:1 mix with normal plasma, a thromboplastin inhibition test that was strongly positive for lupus anticoagulant, and a dilute Russell's viper venom test that was prolonged at 64.3 s (normal 29–46 s) which corrected with the addition of phospholipids. Other coagulation studies, which included anticardiolipin and anti-β2 glycoprotein antibodies, were within normal limits. Erythrocyte sedimentation rate (55 mm/h) and C-reactive protein (5.7 mg/l) were moderately elevated, and the antinuclear antibody assay was elevated at 1:160. Anti-dsDNA was negative. Other studies were normal or negative, including complete blood count, platelet count, renal, liver, and thyroid functions, hemoglobin A1c, and LDL cholesterol. Electrocardiogram and transthoracic echocardiogram were normal.\nA CT scan showed areas of evolving infarction in the right anterior and middle cerebral artery distributions. CT angiography showed bilateral internal carotid artery occlusions extending from the level of the bifurcation to the supraclinoid segments. MRI showed areas of acute infarction within the right middle cerebral artery-anterior cerebral artery watershed territory and chronic infarcts in the left middle cerebral artery-anterior cerebral artery watershed territory (fig. ).\nConventional angiography confirmed bilateral internal carotid artery occlusions in the proximal cervical segments, with reconstitution of the carotid arteries at the supraclinoid segments via the ethmoidal branches of the distal internal maxillary arteries and the ophthalmic arteries (fig. ). Posterior communicating arteries were present bilaterally. The posterior circulation was normal, with extensive collaterals to the anterior circulation via the posterior communicating arteries. No abnormalities concerning for vasculopathy or dissection were noted in the aortic arch or in the carotid, vertebral, subclavian, renal, or femoral arteries.