Sideway Aspiration Technique for Thrombus in a Sharply Bifurcated Branch of a Large Vessel.

Objective: Standard thrombectomy techniques, including stent retrieval and a direct aspiration first pass technique, are not effective when the occluded vessel is narrow and sharply bifurcated from the main trunk. Here, we present a new and alternative method for patients with such anatomical features and describe two cases treated by this method. Case Presentations: Case 1 was a 66-year-old woman who presented with consciousness disturbance and left hemiparesis. MRA suggested a right middle cerebral artery occlusion. Case 2 was an 86-year-old man who presented with sudden onset of consciousness disturbance; MRA indicated occlusion of the basilar artery. Both cases were successfully treated by our new method. First, we navigated a microcatheter, microguidewire, and aspiration catheter into the patent and visible branch adjacent to the occluded branch. The aspiration catheter was then carefully pulled back with continuous mechanical aspiration. When reverse blood flow from the aspiration catheter was suspended, we slightly advanced the catheter and caught the thrombus. Complete recanalization was attained in the two cases treated with this technique, which was named as sideway aspiration technique (SAT). Conclusion: Although it warrants further study, SAT may be a potentially safe and effective method for thrombectomy in cases with thrombus in a sharply bifurcated branch.

Efficacy of combined use of a stent retriever and aspiration catheter in mechanical thrombectomy for acute ischemic stroke.

BACKGROUND: The efficacy of combined stent retriever (SR) and aspiration catheter (AC; combined technique: CBT) use for acute ischemic stroke (AIS) is unclear. We investigated the safety and efficacy of single-unit CBT (SCBT)-retrieving the thrombus as a single unit with SR and AC into the guide catheter-compared with single use of either SR or contact aspiration (CA). METHODS: We analysed 763 consecutive patients who underwent mechanical thrombectomy for AIS between January 2013 and January 2020, at six comprehensive stroke centers. Patients were divided into SCBT and single device (SR/CA) groups. The successful recanalization with first pass (SRFP) and other procedural outcomes were compared between groups. RESULTS: Overall, 240 SCBT and 301 SR/CA (SR 128, CA 173) patients were analyzed. SRFP (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2c, 43.3% vs 27.9%, p<0.001; mTICI 3, 35.8% vs 25.5%, p=0.009) and final mTICI ≥2b recanalization (89.1% vs 82.0%, p=0.020) rates were significantly higher, puncture-to-reperfusion time was shorter (median (IQR) 43 (31.5-69) vs 55 (38-82.2) min, p<0.001), and the number of passes were fewer (mean±SD 1.72±0.92 vs 1.99±1.01, p<0.001) in the SCBT group. Procedural complications were similar between the groups. In subgroup analysis, SCBT was more effective in women, cardioembolic stroke patients, and internal carotid artery and M2 occlusions. CONCLUSIONS: SCBT increases the SRFP rate and shortens the puncture-to-reperfusion time without increasing procedural complications.

Late-onset ornithine transcarbamylase deficiency: a rare cause of recurrent abnormal behavior in adults.

BACKGROUND: Ornithine transcarbamylase is an enzyme of the urea cycle, which produces urea from ammonia. Although ornithine transcarbamylase deficiency mainly occurs as a severe neonatal-onset disease, a late-onset form that could become symptomatic from infancy to adulthood is also known. CASE PRESENTATION: A 34-year-old man presented with sudden onset of abnormal behavior, lethargy, and hyperammonemia (108 µmol/L). He had recently increased daily protein intake, which suggested urea cycle disorder. After initiation of protein-restricted diet and treatment with arginine and sodium phenylbutyrate, his symptoms resolved, along with a decrease in the ammonia level. An R40H(c.119G > A) mutation in the OTC gene was identified. CONCLUSION: Awareness of adult onset ornithine transcarbamylase deficiency in a patient with acute psychiatric symptoms due to hyperammonemia is important.

Use of Middle Cerebral Artery Visualization with Coronal Computed Tomography to Access Target Artery in Mechanical Thrombectomy.

BACKGROUND: When introducing a microguidewire into an occluded vessel during mechanical thrombectomy (MT), visual information on the vessel course distal to the occluded site could help to avoid perforation. We examined whether visualization of the middle cerebral artery (MCA) by coronal images of nonenhanced computed tomography (coronal CT) provides useful preoperative information on the vessel course in the setting of MT. METHODS AND RESULTS: We retrospectively studied 29 patients with ischemic stroke of the internal carotid artery and MCA occlusion who were admitted to our hospital within 4.5 hours from stroke onset and underwent MT. Coronal CT images were preoperatively created by a dedicated workstation and adjusted to visualize the M1 segment of the MCA (M1) and nearby areas. We referred to these images while performing MT. The shape and course of M1 on preoperative coronal CT images were compared with that in intraoperative angiography after recanalization. The median time from the start of imaging to arterial puncture was 40 minutes (interquartile range: 32.5-55.0 minutes). Successful recanalization of the thrombolysis in cerebral infarction 2b-3 was achieved in 89.7% of patients. The degree of matching was assessed as moderate to excellent, and was useful as preoperative information in 27 (93.1%) patients. CONCLUSIONS: Preoperative information on the vessel course by coronal CT well matched that in the intraoperative angiography. Only a little extra time and a small additional procedure are necessary for this technique. The addition of coronal CT images could contribute to a safe and successful MT.

Aspiration Catheter Reach to Thrombus (ART) Sign in Combined Technique for Mechanical Thrombectomy: Impact for First-Pass Complete Reperfusion.

OBJECTIVE: The important factor for successful first-pass complete reperfusion (FPR) after combined techniques for mechanical thrombectomy (MT) is unclear. We consider that for successful FPR, the aspiration catheter (AC) should reach to and hold the thrombus before the device is pulled out. Therefore, we defined an ART (AC reached thrombus) sign characterized by the cessation of reverse blood flow in aspiration pump and deformation of stent retriever (SR) at the tip of AC. The purpose of this study was to identify the impact of the ART sign on the outcomes of the combined techniques. METHODS: A retrospective analysis was conducted between January 2015 and September 2018 on the data of consecutive patients who underwent MT for anterior circulation stroke using both SR and AC at the first-pass procedure. We divided the patients into 2 groups based on whether the first-pass procedure achieved the ART sign (ARTs group) or not (Non-ARTs group). The primary endpoint was FPR defined as modified thrombolysis in cerebral infarction (mTICI) score of 3. RESULTS: Sixty-six patients were included in our study (n = 38, ARTs group; n = 28, Non-ARTs group). There were no differences at mTICI 2b/3 (97.3% versus 89.2%, P = .30), but the FPR and mTICI3 were more common in the ARTs group (81.5% versus 14.2%, P < .001; and 89.4% versus 32.1%, P < .001, respectively). CONCLUSIONS: ART sign in combined technique was found to be an important factor for successful FPR.

Reversible cerebral vasoconstriction complicated with brain infarction immediately after carotid artery stenting.

Reversible cerebral vasoconstriction is a very rare complication after carotid artery stenting (CAS). It has been reported to occur more than several hours after CAS and to have a good clinical course. A 73-year-old man underwent CAS for a high-grade symptomatic stenosis of his left carotid artery. Immediately after CAS, he had consciousness disturbance and right hemiparesis. We first suspected hyperperfusion syndrome, but antihypertensive therapy exacerbated his symptoms. On repeated postoperative angiography, the middle cerebral artery (MCA) appeared to become progressively narrower. Perfusion computed tomography indicated hypoperfusion in the left MCA territory, so we diagnosed the patient with ischemic symptoms due to hypoperfusion associated with MCA vasoconstriction. Although these findings were temporary, right weakness and cognitive dysfunction lingered and caused severe disability. As vasoconstriction after CAS may result in a poor outcome, it must be promptly distinguished and treated accordingly.

Improvement and Aggravation of Spontaneous Unruptured Vertebral Artery Dissection.

BACKGROUND: Intracranial vertebral artery dissection (VAD) is a well-recognized cause of stroke in young and middle-aged individuals, especially in Asian populations. However, a long-term natural course remains unclear. We investigated the long-term time course of VAD using imaging findings to examine the rate and predisposing factors for improvement. METHODS: We registered 56 consecutive patients (40 males; mean age, 51.8 ± 10.7 years) with acute spontaneous VAD and retrospectively investigated neuroimaging and clinical course within 1 month and at 3 months ± 2 weeks, 6 months ± 2 weeks, and 12 months ± 2 weeks after onset to ascertain predisposing factors and time course for improvement. RESULTS: The most common presenting symptoms were headache and/or posterior neck pain, seen in 41 patients (73%). Magnetic resonance imaging showed brainstem and/or cerebellum infarction in only 32 patients (57%). Of the 56 VADs, 16 (28%) presented with pearl and string sign, 5 (9%) with pearl sign, 15 (27%) with string sign, and 20 (36%) with occlusion sign. VAD occurred on the dominant side in 20 patients and on the nondominant side in the other 36 patients. The pearl and string sign was more frequently noted on the dominant side than on the nondominant side (50 vs. 17%, p = 0.008). On the other hand, occlusion occurred more often on the nondominant side than on the dominant side (47 vs. 15%, p = 0.016). Furthermore, the pearl and string sign was more frequently seen in the improvement group (41 vs. 15%, p = 0.028), whereas the occlusion sign was evident more frequently in the nonimprovement group (21 vs. 52%, p = 0.015). Follow-up neuroimaging evaluation was performed at 1 and 3 months in 91% each, and at 6 and 12 months in 82% each. VAD aggravation was identified within 1 month after onset in 14%, while VAD improvement was seen in 14, 38, 50, and 52% at each period, mainly within 6 months after onset. Older patients and current smoking were negatively associated with VAD improvement. CONCLUSIONS: VAD improvement primarily occurs within 6 months after onset, and VAD aggravation within 1 month. It seems that older patients and current smoking are negative predictors of VAD improvement as risk factors, and as image findings, the pearl and string sign is a positive predictor and occlusion a negative predictor.

A case of internal carotid thrombus associated with brain infarction.

A 49-year-old man was transferred to our hospital with chief complaint of global aphasia and weakness of right upper and lower limbs. Brain MRI showed ultra-acute cerebral infarction in left anterior cerebral artery and middle cerebral artery territory and MRA showed occlusion of A2 and M2. Although t-PA was administrated intravenously, symptoms didn't improve and giant internal carotid thrombus (size 6 × 7 × 17 mm) was recognized at left internal carotid artery by carotid ultrasonography. After started anticoagulant therapy, thrombus was miniaturized gradually and finally disappeared. Anticoagulant therapy is effective to internal carotid thrombus and carotid ultrasonography is useful to confirm the effectiveness. We suggest that clinicians should enforce anticoagulant therapy for the first choice to internal carotid thrombus.

Diagnosis and follow-up of posterior inferior cerebellar artery dissection complicated with ischemic stroke assisted by T1-VISTA: a report of two cases.

BACKGROUND: Volume isotropic turbo spin-echo acquisition (VISTA) is a new method similar to the 3D black-blood imaging method that enables visualization of a intramural hematoma. T1-VISTA has recently been applied in the diagnosis of intracranial arterial dissection. However, the identification of an intramural hematoma in posterior inferior cerebellar dissection (PICA-D) by T1-VISTA has only rarely been reported. CASE PRESENTATION: We herein report two patients who suffered from PICA-D complicated with ischemic stroke. Initial magnetic resonance arteriography was not informative, however, T1-VISTA depicted high-intensity signal areas suggesting an intramural hematoma of PICA-D in both cases. The high-intensity signal areas gradually reduced and finally disappeared at 4 months and 5 months after the onset, respectively. CONCLUSION: Our cases demonstrate that T1-VISTA was able to assist in the diagnosis and follow-up of PICA-D.

Dermatitis caused by metal allergy after coil embolization for unruptured cerebral aneurysm.

We report a rare case of metal-induced dermatitis after coil embolization for cerebral aneurysm. A 51-year-old woman experienced a rash around the lips and neck 3 weeks after coil embolization. Judging from the clinical course and results of several patch tests, platinum coils were considered to have induced the dermatitis. Symptoms were relieved with administration of oral steroids. This represents the first report of metal-induced dermatitis after neuroendovascular treatment. The possibility of metal allergy was difficult to suspect preoperatively. However, early evaluation and referral are important when skin symptoms are observed postoperatively.

Dermatitis caused by metal allergy after coil embolization for unruptured cerebral aneurysm.

We report a rare case of metal-induced dermatitis after coil embolization for cerebral aneurysm. A 51-year-old woman experienced a rash around the lips and neck 3 weeks after coil embolization. Judging from the clinical course and results of several patch tests, platinum coils were considered to have induced the dermatitis. Symptoms were relieved with administration of oral steroids. This represents the first report of metal-induced dermatitis after neuroendovascular treatment. The possibility of metal allergy was difficult to suspect preoperatively. However, early evaluation and referral are important when skin symptoms are observed postoperatively.

Carotid artery calcification on multislice detector-row computed tomography.

BACKGROUND: To determine the underlying conditions that affect the degree of calcification of carotid arterial plaques, measured quantitatively using multidetector row computed tomography (MDCT), and to study the association of carotid calcification with clinical symptomatology. METHODS: We measured the calcification volume of stenotic lesions at the carotid bifurcation using MDCT in 84 consecutive patients who were scheduled to undergo carotid revascularization. These results were compared with the clinical and radiological characteristics of the patients. RESULTS: On MDCT, calcification in the carotid plaques was present in 78 patients (93%). Compared to the other patients, patients in the highest quartile of calcification volume (quartile 4) had higher serum creatinine levels (p < 0.001) and tended to have fewer symptomatic ischemic events in the territory of the affected carotid artery in the preceding 6 months (29 vs. 49%, p = 0.099); in particular, there were fewer transient symptoms (5 vs. 27%, p = 0.032) and symptoms possibly occurring due to local embolism (14 vs. 37%, p = 0.045). On ultrasound, plaque ulceration was less prevalent in patients in quartile 4 than in the remaining patients (5 vs. 29%, p = 0.026), although the severity of carotid stenosis was similar among all the quartiles. CONCLUSIONS: Renal dysfunction was associated with enhanced carotid plaque calcification. Patients with severe carotid calcification were found to have a low risk of recent ischemic stroke, presumably due, in part, to a lower prevalence of emboligenic carotid ulceration. MDCT was valuable for the quantitative evaluation of carotid calcification.

Antithrombotic therapy and predilection for cerebellar hemorrhage.

BACKGROUND: With the recent increase in the use of antithrombotic therapy, intracerebral hemorrhage (ICH) has been found to be a common complication. We determined whether the use of oral antithrombotic therapy and the patients' preexisting comorbidities were predictive of cerebellar hemorrhage (CH; previously reported to be associated with anticoagulants) as compared to other ICH, and whether antithrombotic therapy affected the clinical severity of CH. METHODS: A study of 327 consecutive patients hospitalized in our institute within 3 days after the onset of ICH, including 38 patients with a CH. RESULTS: CH accounted for 12% of all ICH, 75% of which occurred in patients on warfarin therapy with an international normalized ratio (INR) for prothrombin time >2.5 (p < 0.0001), and 33% of which occurred in patients on ticlopidine therapy (p = 0.017). Warfarin therapy with an INR >2.5 and high blood glucose on admission were independently predictive of CH as compared to other ICH. In addition, previous ischemic stroke (p = 0.002) and heart diseases (p = 0.018) were more prevalent in patients with CH than in those with other ICH. The number of major arteriosclerotic comorbidities and risk factors was also independently predictive of CH risk. CONCLUSIONS: We confirmed that warfarin therapy with an INR >2.5 is associated with CH. Patients with CH frequently had arteriosclerotic comorbidities requiring antithrombotic therapy that can complicate their acute management.

Serial evaluation of acute cerebral hyperperfusion by transcranial color-coded sonography.

Using transcranial color-coded sonography (TCCS), we evaluated the acute changes in the hemodynamics of cerebral hyperperfusion in two cases. The mean flow velocity of the cerebral arteries increased at the onset of clinical symptoms, together with an increase in the regional cerebral blood flow (rCBF). In serial follow-up studies, the flow velocity gradually returned to normal in parallel with the normalization of the rCBF values. TCCS can be useful for evaluation of acute cerebral hyperperfusion.

Successful high dose glucocorticoid treatment for subacute neuromyelitis optica with systemic lupus erythematosus.

A 54-year-old Japanese woman with a 6-year history of systemic lupus erythematosus (SLE) was admitted to our hospital suffering from acute blindness in her right eye. Her condition recovered after steroid pulse therapy, however, 18 months later she suffered from nuchal pain for 2 weeks after which right hemiparesis with urinary incontinence developed. A spinal magnetic resonance imaging (MRI) revealed cord swelling from C2 to C7. She was diagnosed with neuromyelitis optica (NMO) and intravenous steroid administrations were immediately commenced. Her condition promptly improved. This case was unique because the steroid treatment was quite effective for this case of myelitis, which had passed the acute phase. We supposed that, because most of the lesion was not necrotic or demyelinated, but rather showed edematous change caused by vasculitis based on autoimmune pathogenesis, the symptoms progressed rather gradually and improved promptly in response to glucocorticoid treatment.

Superficial temporal artery duplex ultrasonography for improved cerebral hemodynamics after extracranial-intracranial bypass surgery.

BACKGROUND: To investigate the utility of superficial temporal artery (STA) duplex ultrasonography (STDU) for evaluating the improvement of the cerebral hemodynamics after extracranial-intracranial (EC-IC) bypass. METHODS: This study included 40 consecutive patients who underwent EC-IC bypass for occlusive disease of cerebral arteries. STDU was performed to measure the flow velocity, pulsatility index, and diameter of the operated STA before and 14 days after EC-IC bypass. Regional cerebral blood flow (rCBF) and acetazolamide (ACZ) reactivity of the ipsilateral middle cerebral artery (MCA) territory were evaluated by quantitative single-photon emission computed tomography with the ACZ challenge test. We investigated the correlation between STA flow velocity/diameter and rCBF/ACZ reactivity in the ipsilateral MCA territory. RESULTS: Mean flow velocity (MFV; 26.3 +/- 8.8 to 55.3 +/- 16.3 cm/s, p < 0.0001) and diameter (1.57 +/- 0.24 to 2.26 +/- 0.29 mm, p < 0.0001) of the STA, and rCBF (29.1 +/- 3.1 to 35.0 +/- 6.4 ml/100 g/min, p < 0.0001) and ACZ reactivity (-0.02 +/- 0.10 to 0.28 +/- 0.21, p < 0.0001) of the MCA territory increased after EC-IC bypass compared with the baseline values. STA MFV was significantly correlated with the rCBF 14 days after EC-IC bypass (R = 0.70, p < 0.0001). A cutoff value of postsurgical STA MFV greater than 48.5 cm/s yielded the highest diagnostic accuracy (sensitivity 86%; specificity, 82%) for rCBF > or = 32 ml/100 g/min after EC-IC bypass. CONCLUSIONS: STDU was available for evaluating postsurgical patency of the bypass flow and the rCBF of the ipsilateral MCA territory. The mean blood flow velocity of the operated STA is a highly sensitive parameter for predicting rCBF in the ipsilateral MCA territory after EC-IC bypass.

[Behavioral situation at onset of paradoxical brain embolism due to patent foramen ovale].

The goal of this study was to determine whether there was difference in behavioral situation at onset of stroke between the patients with right-to-left shunt whose stroke was diagnosed as paradoxical brain embolism according to the new criteria proposed by Strategies against Stroke Study for Young Adults in Japan (SASSY-Japan) and whose stroke was not. Among 365 consecutive patients with possible acute ischemic stroke who underwent transesophageal echocardiography, we compared clinical profiles of the following three patient groups: patients with patent foramen ovale whose stroke was diagnosed as paradoxical brain embolism (group A), patients with patent foramen ovale whose stroke was not diagnosed as paradoxical brain embolism (group B), and patients without patent foramen ovale whose stroke was diagnosed as cardiogenic brain embolism (group C). Patent foramen ovale was present on echocardiogram in 76 of 365 patients (21%). Among them, 19 patients were classified into group A and 34 into group B. Group C was composed of 69 patients. At stroke onset, 3 patients in group A took behavior with positive Valsalva maneuver, 2 in group B, and 1 in group C. Similarly at stroke onset, 4 patients in group A just stood up from long-time sitting position, 1 in group B, and 1 in group C. In all, stroke onset following Valsalva maneuver or long-time sitting position was positive in 37% of group A, 9% of group B, and 3% of group C, and was most frequent in group A (p < 0.0001). In group A, the frequency of Valsalva maneuver or long-time sitting position at stroke onset was higher than the frequency of detection of venous thrombus (21%). The result indicates that Valsalva maneuver and long-time sitting position contribute to occurrence of paradoxical brain embolism. We think that these behavioral situations are appropriate diagnostic criteria for paradoxical brain embolism.

Recurrent small-artery disease in hyperhomocysteinemia: widowers' stroke syndrome?

Hyperhomocysteinemia is thought to cause ischemic strokes. We report two middle-aged widowers with frequent recurrences of small-artery strokes, two capsular infarcts and a thalamic hemorrhage in one patient, and two thalamic and pontine infarcts in the other. Blood tests following the final stroke showed hyperhomocysteinemia and methylenetetrahydrofolate reductase C677T gene mutation, with low concentration of vitamin B6. Multivitamin supplementation normalized plasma homocysteine levels in both patients. Hyperhomocysteinemia is treatable; therefore, serum homocysteine should be measured as a potential risk factor for stroke recurrence in relatively young patients with recurrent small-artery infarctions or hemorrhage, especially those with insufficient lifestyle factors.

Diagnostic impact of transcranial color-coded real-time sonography with echo contrast agents for hyperperfusion syndrome after carotid endarterectomy.

BACKGROUND AND PURPOSE: The purpose of the present study was to evaluate availability of transcranial color-coded real-time sonography (TCCS) to detect hyperperfusion after carotid endarterectomy (CEA). METHODS: This prospective study included 105 consecutive patients who underwent CEA for severe carotid stenosis. TCCS with echo contrast agents was performed serially to evaluate flow velocity of the middle cerebral artery (MCA). Regional cerebral blood flow (rCBF) and vasodilatory capacity of the MCA territory were evaluated using single-photon emission computed tomography. We compared the changes in MCA flow velocity with rCBF. RESULTS: Using echo contrast agents, we could evaluate the MCA flow in 95 (90%) of 105 patients. Twelve patients showed hyperperfusion syndrome. Changes in the MCA mean flow velocity (MFV) before and 4 days after CEA were significantly correlated with those in rCBF (r=0.48; P<0.0001). An increase of >50% in MCA MFV was observed within 4 days after CEA in all 12 patients with hyperperfusion syndrome. Multivariate analysis revealed that reduced vasodilatory capacity (odds ratio, 0.14; 95% CI, 0.04 to 0.46) was an independent risk factor for a 1.5-fold increase in the MFV of MCA ipsilateral to CEA. CONCLUSIONS: Findings of a 1.5-fold increase in the MCA MFV can accurately identify those patients with high risk of developing post-CEA hyperperfusion syndrome. TCCS with echo contrast agents is available for the evaluation of hyperperfusion after CEA.

Reversible posterior leukoencephalopathy syndrome in a postpartum woman without eclampsia.

We report a patient who developed reversible posterior leukoencephalopathy syndrome (RPLS) in puerperium without preeclampsia-eclampsia or chronic hypertension. The woman suddenly complained of visual loss and headache 10 days after delivery caused by edematous lesions mainly distributed in the bilateral occipital lobe. Apparent diffusion coefficient map was useful for distinction of this vasogenic edema from cytotoxic edema due to brain infarction. Under the diagnosis of RPLS, we successfully treated her disease using a trinitroglycerin as an antihypertensive, a hyperosmolar agent, methylprednisolone, and a free radical scavenger. Postpartum women may have the risk of development of RPLS even without preeclampsia-eclampsia. Vascular endothelial dysfunction may trigger RPLS, in addition to acute and modest increase in systemic pressure.