First Experience With the Utility of ReMAP (Repeatable Microcatheter Access Port) in Portal Vein Stenting.

Portal vein stenting is a treatment option for portal hypertension caused by extrahepatic portal vein obstruction or stenosis. However, limited pathways to approach the portal vein are available, hindering re-intervention in the portal vein. Portal vein puncture through the transjugular intrahepatic portosystemic shunt route is less invasive and considered suitable for portal vein stenting. Furthermore, transjugular intrahepatic portosystemic shunting facilitates repeat approaches to the portal vein. However, a transjugular intrahepatic portosystemic shunt stent is not recommended unless necessary because of adverse events, and cannot be retrieved, once placed. Herein, we report on a novel approach using the repeatable microcatheter access port: ReMAP™ (Toray, Tokyo, Japan), a central vein port into which a 2.9 Fr catheter can be inserted. We used it for a repeat approach to the portal vein with only one puncture and without placing a transjugular intrahepatic portosystemic shunt stent.

Intraoperative application of indocyanine green and temporary venous occlusion test to assess collateral flow during microvascular decompression for venous-related trigeminal neuralgia: illustrative case.

BACKGROUND: In microvascular decompression (MVD) for vein-related trigeminal neuralgia (TN), determining whether transection of the offending vein is safe can be challenging. Here, the authors present a case of vein-related TN successfully treated by sacrificing the offending vein on the basis of findings from indocyanine green (ICG) video angiography and a temporary venous occlusion test to assess the collateral flow of the offending vessel. OBSERVATIONS: A 43-year-old man presented with TN, which had failed to respond to previous medical therapy. Gadolinium-enhanced magnetic resonance imaging (MRI) revealed that the transverse or superior petrosal vein was the offending vein. The patient underwent MVD. Because the transposition of the offending vein was anatomically challenging, a temporary vein occlusion test was performed using ICG video angiography. During and after temporary occlusion, bidirectional flow in the offending vein was observed, suggesting collateral flow even after vein occlusion. On the basis of these findings, the offending vein was transected, resulting in relief from pain without any complications. Postoperative MRI revealed no new lesions in the brainstem or the cerebellar hemisphere. The patient has been free from neuralgia for 6 months. LESSONS: The temporary vein occlusion test under ICG video angiography was useful for evaluating collateral flow in the offending vein in TN.

Clinical risk factors for portal hypertension-related complications in systemic therapy for hepatocellular carcinoma.

BACKGROUND: During systemic therapy, the management of portal hypertension (PH)-related complications is vital. This study aimed to clarify factors associated with the incidence and exacerbation of PH-related complications, including the usefulness of contrast-enhanced computed tomography (CECT) in the management of PH-related complications during systemic therapy. METHODS: A total of 669 patients who received systemic therapy as first-line treatment (443 patients for sorafenib, 131 for lenvatinib, and 90 for atezolizumab/bevacizumab [ATZ/BEV]) were enrolled in this retrospective study. Additionally, the lower esophageal intramural vessel diameters (EIV) on CECT and endoscopic findings in 358 patients were compared. RESULTS: The cutoff values of the EIV diameter on CECT were 3.1 mm for small, 5.1 mm for medium, and 7.6 mm for large varices, demonstrating high concordance with the endoscopic findings. esophageal varices (EV) bleeding predictors include EIV ≥ 3.1 mm and portal vein tumor thrombosis (PVTT). In patients without EV before systemic therapy, factors associated with EV exacerbation after 3 months were EIV ≥ 1.9 mm and ATZ/BEV use. Predictors of hepatic encephalopathy (HE) include the ammonia level or portosystemic shunt diameter ≥ 6.8 mm. The incidence of HE within 2 weeks was significantly higher (18%) in patients with an ammonia level ≥ 73 µmol/L and a portosystemic shunt ≥ 6.8 mm. The exacerbating factors for ascites after 3 months were PVTT and low albumin levels. CONCLUSIONS: Careful management is warranted for patients with risk factors for exacerbation of PH-related complications; moreover, the effective use of CECT is clinically important.

Ionized acrylamide-based copolymer / terpolymer hydrogels for recovery of positive and negative heavy metal ions.

In this study, we explored the effective capture of both cations and anions onto a single adsorbent. Acrylamide (AAm) served as the polymer backbone, onto which co-monomers sodium p-styrenesulfonate (SS) and N,N-dimethylaminopropyl acrylamide (DMAPAA) were grafted, creating ionized polymer hydrogel adsorbents. These adsorbents were engineered for the synergistic separation and recovery of heavy metal cations and anions from concentrated solutions, focusing specifically on industrially significant ions such as Ni2+-, Cu2+, Zn2+ and (Cr2O7)2-. The adsorption and desorption behaviors of the AAm terpolymer hydrogels were investigated across various pH solutions, considering the competition and concentrations of these specific metal ions. Moreover, the study delved into the effects of the internal pH environment within the hydrogel adsorbents, determining its impact on the type of metal adsorbed and the adsorption capacity. Our findings indicated that the adsorption of cations was enhanced with a higher proportion of SS relative to DMAPAA in the hydrogel. In contrast, significant anion capture occurred when the concentration of DMAPAA exceeded that of SS. However, equal ratios of SS and DMAPAA led to a noticeable reduction in the adsorption of both types of substrates, attributed to the counteractive nature of these co-monomers. To enhance the adsorption efficiency, it may be necessary to consider methods for micro-scale separation of the two types of monomers. Additionally, the adsorption capacity was observed to be directly proportional to the swelling capacity of the hydrogels. For complete desorption and separation of the cations and anions from the adsorbent, the application of concentrated NaOH solutions followed by HNO3 was found to be essential. Given the varying concentrations of cation and anion pollutants, often present in heavy metal factory effluents, it is crucial to fine-tune the ratios of DMAPAA and SS during the synthesis process. This adjustment ensures optimized efficiency in the decontamination and recovery of these significant heavy metal ions.

Feasibility of Diffusion-weighted Imaging (DWI) for Assessing Cerebrospinal Fluid Dynamics: DWI-fluidography in the Brains of Healthy Subjects.

PURPOSE: The present study aimed to investigate whether diffusion-weighted imaging (DWI) can qualify and quantify cerebrospinal fluid (CSF) dynamics in the brains of healthy subjects. For this purpose, we developed new DWI-based fluidography and compared the CSF dynamics seen on the fluidography with two apparent diffusion coefficients obtained with different DWI signal models at anatomical spaces filled by CSF. METHODS: DWI with multiple b values was performed for 10 subjects using a 7T MRI scanner. DWI-fluidography based on the DWI signal variations in different motion probing gradient directions was developed for visualizing the CSF dynamics voxel-by-voxel. DWI signals were measured using an ROI in the representative CSF-filled anatomical spaces in the brain. For the multiple DWI signals, the mono-exponential and kurtosis models were fitted and two kinds of apparent diffusion coefficients (ADCC and ADCK) were estimated in each space using the Gaussian and non-Gaussian diffusion models, respectively. RESULTS: DWI-fluidography could qualitatively represent the features of CSF dynamics in each anatomical space. ADCs indicated that the motions at the foramen of Monro, the cistern of the velum interpositum, the quadrigeminal cistern, the Sylvian cisterns, and the fourth ventricle were more drastic than those at the subarachnoid space and anterior horns of the lateral ventricle. Those results seen in ADCs were identical to the findings on DWI-fluidography. CONCLUSION: DWI-fluidography based on the features of DWI signals could show differences of CSF dynamics among anatomical spaces.

Percutaneous Transhepatic Direct Portosystemic Shunt for a Patient With Budd-Chiari Syndrome Using a Balloon as a Target in a Stenotic Inferior Vena Cava.

Budd-Chiari syndrome (BCS) patients with portal hypertension are often treated with a direct intrahepatic portosystemic shunt (DIPS) or transjugular intrahepatic portosystemic shunt (TIPS) and angioplasty. DIPS can be problematic, however, due to the technical difficulty of the procedure. To address this problem, we describe a method using the balloon used for inferior vena cava (IVC) dilatation as a puncture target to safely perform DIPS in a BCS patient with complete hepatic vein occlusion and stenosis of the IVC. To perform balloon dilation, the puncture is made through the internal jugular vein, and the guidewire is advanced to the IVC with stenosis. After dilatation of the IVC, the direct left lateral subdistrict branch of the portal vein is percutaneously punctured directly from the cardiac fossa (targeting the inflated balloon in the IVC), and the IVC puncture is done through the portal vein. After creating a pull-through route, a stent is placed between the left portal vein and the IVC. The procedure is completed without any complications. This technique has the potential to form the basis of a safe and reliable DIPS procedure.

A case of intracerebral hemorrhage due to cerebral hyperperfusion after stenting for acute cervical carotid artery dissection.

Urgent carotid artery stenting (CAS) is effective for treatment-resistant cervical internal carotid artery dissection (CICAD). We experienced a 37-year-old woman who presented with sudden onset of cervical pain, blurred vision in the right eye, and numbness in the left upper and lower extremities. Due to neurological deterioration resulting from hemodynamic impairment, urgent CAS was performed under general anesthesia. Brain perfusion single-photon emission computed tomography performed immediately after CAS showed increased blood flow in the right hemisphere despite no evidence of hemorrhage or ischemic lesion on brain computed tomography (CT). Systolic blood pressure was therefore strictly controlled below 110 mm Hg perioperatively. However, the day after CAS, a follow-up CT showed intracerebral hemorrhage in the right temporal lobe. Urgent CAS in patients with progressive deterioration of hemodynamic impairment caused by CICAD may induce intracerebral hemorrhage due to cerebral hyperperfusion. Care should be taken to recognize and manage this phenomenon during the perioperative period.

Delayed blink R1 latency in a patient with trigeminal neuralgia due to a contralateral vestibular schwannoma: An illustrative case.

Background: Although the blink reflex (BR) is effective in objectively evaluating trigeminal neuropathy, few studies have demonstrated its effect on trigeminal neuralgia (TN). The authors report a patient with TN due to contralateral vestibular schwannoma (VS) functionally diagnosed by delayed R1 latency of the BR. Case Description: A 36-year-old man presented with left-sided deafness and paroxysmal facial pain in the right V1-3 area. Magnetic resonance imaging (MRI) showed a solid cystic mass compressing the right pons and left brainstem at the left cerebellopontine angle. Although preoperative BR evoked by right supraorbital nerve stimulation-induced delayed ipsilateral R1 latency and normal ipsilateral and contralateral R2 responses, the BR latency evoked by left supraorbital nerve stimulation was normal, indicating deficits in the principal nucleus of the trigeminal nerve in the right pons. The symptoms of TN disappeared after the removal of the VS. Postoperative MRI showed subtotal removal of the tumor and sufficient decompression of the pons and cerebellopontine cistern. The R1 latency returned to normal 50 days after surgery. Conclusion: The perioperative BR test was not only useful for objective evaluation of the localization of trigeminal neuropathy but also correlated with the symptoms of TN.

Potential of circulating receptor-interacting protein kinase 3 levels as a marker of acute liver injury.

The pathogenesis of acute liver failure (ALF) involves cell death. Necroptosis is a newly suggested programmed cell death, and receptor-interacting protein kinase 3 (RIPK3) has been reported as a marker for necroptosis. However, there are few reports on necroptosis in ALF. Therefore, we evaluated the role of cell death markers such as cytokeratin (CK) 18, cleaved CK (cCK) 18, and RIPK3 in ALF, as well as cytokines and hepatocyte growth factor (HGF). Seventy-one hospitalized patients with acute liver injury (38 nonsevere hepatitis [non-SH]/22 severe hepatitis [SH]/11 ALF) were studied. No significant difference was found for cytokines, but a substantial increase in HGF levels was found following the severity of hepatitis. The non-SH group had lower levels of CK18 and cCK18 than the SH/ALF group. RIPK3 was significantly lower in the non-SH/SH group than in the ALF group. HGF, RIPK3, and albumin levels were found to be important predictive variables. The present study suggests that cCK18, CK18, and RIPK3 are associated with the severity of hepatitis. RIPK3 and other markers related cell death may be useful for understanding the pathogenesis of ALF and as a prognostic marker of acute liver injury.

Estimation of the effect of atezolizumab plus bevacizumab on pulmonary arterial hypertension using computed tomography in HCC patients.

The effect of the combination of atezolizumab and bevacizumab (Atez/Bev) for hepatocellular carcinoma (HCC) on pulmonary arterial hypertension (PAH) is unknown. Estimation of PAH by using computed tomography (CT) has recently been proposed. Thus, we aimed to estimate the effect of Atez/Bev on PAH using CT. Altogether, 113 patients who received Atez/Bev for HCC were enrolled. Probable PAH was defined as the diameter of the main pulmonary artery (mPA-D) ≥ 33 mm, whereas suspicious PAH was defined as mPA-D ≥ 29 mm or mPA-D/the diameter of the ascending aorta (aAo-D) ≥ 1.0. Before treatment, probable/suspicious PAH were diagnosed in 7 (6.7%)/22 (21.0%) patients, respectively. mPA-D and mPA-D/aAo-D significantly increased after induction of Atez/Bev. The increment of mPA-D was correlated with the occurrence of post-treatment respiratory/heart failure. In analysis of 55 patients who underwent CT at 3 months after the last dose of Atez/Bev, mPA-D and mPA-D/aAo-D significantly decreased. However, in the group with continuous treatment of other molecular-targeted drugs after Atez/Bev, mPA-D and mPA-D/aAo-D showed no significant change. In conclusion, PAH may not be a rare complication in patients with HCC and should be managed carefully because of the possible negative effect of Atez/Bev on PAH.

Cabozantinib for Advanced Hepatocellular Carcinoma in the Latest Real-World Practice: A Multicenter Retrospective Analysis.

BACKGROUND: Cabozantinib was found to be effective as a second- or third-line treatment after sorafenib in patients with advanced hepatocellular carcinoma (HCC) in the phase 3 CELESTIAL trial. So far, as immunotherapy has substituted molecular target agents as the primary systemic therapy for advanced HCC, cabozantinib is extensively used in the latest real-world clinical practice in a greatly different position than that shown by the CELESTIAL trial. In the current analysis, we examined the safety and effectiveness of cabozantinib administration in real-life settings for patients with advanced HCC. METHODS: We retrospectively obtained data from patients with advanced HCC who received cabozantinib in three institutions in Japan between 14 September 2018 and 30 November 2021. RESULTS: During the study period, 23 patients with advanced HCC received cabozantinib. Our cohort included 21.7% of patients with Child-Pugh class B, and 52.2% of patients in fourth line or later. The median progression-free survival of patients given cabozantinib was 3.7 months. Regarding patients with Child-Pugh class B or administration in fourth line or later, the discontinuation rate due to adverse events in patients who initialized at 40 or 20 mg was lower than those who initialized at 60 mg (42.9% versus 75.0%). Patients who were able to continue treatment with cabozantinib for more than 3 months were more likely to undergo dose reduction than those who did not (85.7% versus 25.0%). CONCLUSIONS: Cabozantinib has recently been administered to a diverse range of patients, including those who were not enrolled in the CELESTIAL trial. Deliberate dose reduction could potentially offer clinical benefits to patients with impaired liver function. Furthermore, managing adverse events by reducing the dose could play a crucial role in extending the duration of treatment with cabozantinib. The preprint version of this work is available on https://www.researchsquare.com/article/rs-2655181/v1 .

Utility of manual venous compression during transvenous Onyx injection for a scalp arteriovenous fistula: illustrative case.

BACKGROUND: When performing transvenous liquid embolization for scalp arteriovenous fistulas, multiple networks of venous drainage could limit effective retrograde penetration of embolic agents into feeding arteries, resulting in incomplete obliteration. A salvage technique to achieve effective Onyx penetration with manual venous compression during transvenous embolization is demonstrated. OBSERVATIONS: A 43-year-old man presented with a progressively enlarging mass on his left temporal scalp that was first noticed approximately 20 years earlier. External carotid artery injection showed two scalp arteriovenous fistulas (AVFs). The patient received endovascular embolization. After successful transarterial obliteration of one AVF, transvenous Onyx embolization was performed for another AVF located in the subcutaneous layer. To avoid unnecessary Onyx migration into multiple venous networks, several coils were put in a venous pouch as a scaffold for the Onyx, and feeding arteries were temporarily occluded. Despite these adjunctive techniques, the Onyx migrated into multiple veins and even toward the orbit without complete fistula obliteration. Thereafter, Onyx was injected under manual compression of venous outlets from the pouch, resulting in complete obliteration. LESSONS: Manual compression of venous outlets can be used as a salvage procedure during transvenous Onyx embolization for a scalp AVF. A surgeon's radiation exposure can be reduced by step-by-step adjunctive procedures.

Cerebral protection during retrograde brachiocephalic artery stenting using a single filter and increased subclavian steal phenomenon: illustrative case.

BACKGROUND: Cerebral protection during brachiocephalic artery (BCA) stenting is important. However, the maneuver is sometimes challenging because both the internal carotid artery (ICA) and vertebral artery (VA) should be protected. Herein, the authors present an alternative cerebral protection technique involving filter protection for the ICA and hemodynamic protection for the VA during retrograde BCA stenting. OBSERVATIONS: A 64-year-old man with a thoracic aortic aneurysm presented with cold sensation and numbness in his right arm due to BCA stenosis. Endovascular stenting under cerebral protection was planned. Cerebral protection was attempted through the brachial access. Despite the successful placement of the filter in the ICA, selective catheterization of the VA failed. Furthermore, repeated transfemoral catheterization of the BCA was unsuccessful. Concerning a thoracic aortic aneurysm injury, the authors performed retrograde BCA stenting using a transbrachial approach. Hemodynamic protection of the VA was provided by increasing the subclavian steal phenomenon that resulted in successful recanalization of the BCA. LESSONS: Retrograde BCA stenting performed while protecting the ICA with a filter and the right VA by increasing the subclavian steal phenomenon was successful. This simple technique is feasible, especially in patients with steno-occlusive lesions of the BCA concurrent with the dominant vertebra/vertebral collateral pathway.

Rupture of Vertebral Artery Dissecting Aneurysm after mRNA Anti-COVID-19 Vaccination: A Report of Two Cases.

The coronavirus disease 2019 (COVID-19) pandemic continues to spread around the world, and widespread vaccination is considered the most effective way to end it. Although the efficacy of COVID-19 vaccines has been confirmed, their safety remains a concern. In this paper, we report two cases of ruptured vertebral artery dissecting aneurysm (VADA) immediately after messenger RNA (mRNA) anti-COVID-19 vaccination. In Case 1, a 60-year-old woman experienced sudden headache 3 weeks before her first dose of the Moderna mRNA-1273 COVID-19 vaccine. Magnetic resonance imaging showed dilatation of the right vertebral artery (VA) without intracranial hemorrhage. A day after the vaccination, she developed subarachnoid hemorrhage with pulmonary effusion due to a ruptured right VADA. She underwent endovascular internal trapping and parent artery occlusion under general anesthesia. In Case 2, a 72-year-old woman with a previous history of the left VA occlusion due to arterial dissection developed subarachnoid hemorrhage 7 days after the first dose of the Pfizer-BioNTech BNT162b2 COVID-19 mRNA vaccine due to a ruptured right VADA and underwent stent-assisted coil embolization under general anesthesia. The postoperative courses of these two cases were uneventful. The accumulation of more cases and further study are warranted to clarify the relationship between COVID-19 mRNA vaccination and ruptured intracranial dissecting aneurysms.

Bowel Obstruction due to Shiitake Mushrooms: Diagnostic Features on Computed Tomography.

Shiitake mushrooms are edible mushrooms popular in East Asian cuisine. We herein report a 69-year-old man with abdominal distension and vomiting after ingesting several pieces of sautéed Shiitake mushrooms. Abdominal computed tomography (CT) revealed ring-shaped and crescent-shaped low-density objects (-100 to -300 Hounsfield units) in the ileum. Based on the specific shapes and CT numbers of the foreign bodies, he was diagnosed with small bowel obstruction due to Shiitake mushrooms. After conservative treatment, he passed four pieces of Shiitake mushrooms. Despite the rarity, the condition can be diagnosed before exploratory surgery by careful and detailed interpretation of CT findings.

Successful Leptomeningeal Enhancement in a Patient with Tandem Occlusion of a Carotid and Middle Cerebral Artery Following Carotid Artery Stenting for Contralateral Carotid Artery Stenosis.

Objective: Although the presence of leptomeningeal anastomosis is known as a predictor of favorable outcome in patients with acute large vessel occlusion, the efficacy of enhancing leptomeningeal collateral flow has rarely been demonstrated. Case Presentation: A 73-year-old man previously diagnosed with asymptomatic bilateral carotid stenosis was admitted to our emergency department 2 hours after the onset of fluctuating symptoms, including aphasia, left conjugate deviation, and right hemiparesis. CT demonstrated no hemorrhagic lesion. Considering the history of the patient, emergent angiography was performed and demonstrated tandem occlusion of the left cervical internal carotid artery (ICA) with left common carotid injection, leptomeningeal flow compensating for distal territory of occluded segment of left middle cerebral artery (MCA) via the left anterior cerebral artery through severe cervical ICA stenosis with right common carotid injection, and the proximal segment of the left MCA through the posterior communicating artery and occlusion of the M2 segment with left vertebral injection. Given the results of angiography and fluctuating symptoms, hemodynamic insufficiency was considered the underlying stroke mechanism for this case. Although recanalization of tandem lesions was initially considered, the risk of distal clot migration was a concern, so the patient underwent right carotid artery stenting (CAS) to enhance leptomeningeal collateral flow. This resulted in immediate resolution of symptoms after right CAS. Conclusion: Stenting for carotid artery stenosis contralateral to tandem occlusive lesion may offer an effective alternative when both Willisian and leptomeningeal collaterals are robust.

Identification of the Distal End of Carotid Plaque Using 3-Dimensional Fast Spin Echo T1-Weighted Magnetic Resonance Plaque Imaging.

BACKGROUND: Complete removal of the distal end of the plaque is an important requirement in carotid endarterectomy (CEA) to avoid postoperative complication. Preoperative identification of the distal end of plaque contributes to complete plaque removal. Three-dimensional (3D) magnetic resonance (MR) plaque imaging has been widely used to evaluate carotid plaque characterization. The purpose of the present study was to determine whether preoperative 3D fast spin echo (FSE) T1-weighted MR plaque imaging could identify the distal end of carotid plaque. METHODS: This study was designed as a prospective cohort study. We examined 50 patients with cervical internal carotid artery (ICA) stenosis who underwent CEA. 3D-FSE T1-weighted MR plaque imaging of the affected carotid bifurcation was preoperatively performed using a 1.5-T scanner. Identification of the distal end of plaque (DEMRI) on MR plaque imaging was performed and the distance from the baseline (DistanceMRI) was measured. Intraoperatively, the superimposed distal end of carotid plaque (Esim) was marked on the ICA according to the measurement on MR plaque imaging. The actual distal end of plaque (DECEA) was then identified after arteriotomy and the difference (DifferenceCEA-MRI) between Esim and DECEA was measured. Contrast ratio of carotid plaque and tortuosity of the ICA were calculated using MR plaque imaging. RESULTS: Interobserver agreements in measurement of DistanceMRI were excellent (intraclass correlation coefficient, .955; 95% confidence interval, .922-.974). In 28 patients (56%), Esim was identical to DECEA. Mean DifferenceCEA-MRI was 1.32 ± 1.77 mm. DifferenceCEA-MRI was significantly greater with fibrotic plaque (4.14 ± 1.21 mm) than with lipid-rich or necrotic plaque (.43 ± .87 mm; P < .05) or hemorrhagic plaque (1.27 ± 1.64 mm; P < .05). Mean DifferenceCEA-MRI was significantly greater in the group with tortuosity of the ICA less than 120° (3.86 ± 1.77 mm) than in the group with greater than or equal to 120° but less than or equal to 150° (1.15 ± 1.51 mm; P < .05) or greater than150° (0.50 ± 1.10 mm; P < .05). No patients showed residual stenosis after surgery on postoperative MR angiography. CONCLUSIONS: Using 3D-FSE T1-weighted MR plaque imaging allowed identification of the distal end of carotid plaque and contributed to complete removal of the plaque, although it may be reduced for cases with low-signal-intensity plaque or severe tortuosity of the ICA.

Comparison of Effects between Clopidogrel and Cilostazol on Cerebral Perfusion in Nonsurgical Adult Patients with Symptomatically Ischemic Moyamoya Disease: Subanalysis of a Prospective Cohort.

BACKGROUND AND PURPOSE: Adult patients with symptomatically ischemic moyamoya disease (MMD) initially undergo medical treatment alone including antiplatelet drugs when symptomatic cerebral hemispheres do not exhibit hemodynamic compromise. The purpose of the present study subanalyzing the same patient cohort used in a previous study was to determine which antiplatelet drug, clopidogrel or cilostazol, provides better improvement of cerebral perfusion in such patients. METHODS: All patients without cerebral misery perfusion on 15O gas positron emission tomography (PET) did not undergo revascularization surgery and were treated with medication alone, including antiplatelet therapy. Patients ≥50years and <50years initially received clopidogrel and cilostazol, respectively. When a patient suffered side effects of an antiplatelet drug, they were switched to the other antiplatelet drug. Cerebral blood flow (CBF) in the symptomatic hemisphere was measured at inclusion and at 2years after inclusion using 15O gas PET. RESULTS: Of 68 patients, 31 and 38 were treated with clopidogrel and cilostazol, respectively, for 2years after inclusion. For patients treated with clopidogrel, CBF did not differ between first and second PET. For patients treated with cilostazol, CBF was significantly greater in the second PET than in the first PET. On multivariate analysis, cilostazol administration was an independent predictor of CBF improvement in the symptomatic hemisphere (95% confidence interval, 1.34-139.20; P =.0271). CONCLUSIONS: Cilostazol improves cerebral perfusion better than clopidogrel in adult patients with symptomatically ischemic MMD not accompanied by misery perfusion.