Coil embolization of recurrent ruptured vertebral artery dissection through a marathon microcatheter: A case report.

A 56-year-old healthy woman presented with subarachnoid hemorrhage caused by ruptured vertebral artery dissecting aneurysm and was treated with internal trapping of the affected site including the aneurysm. She suffered rebleeding due to recanalization of the aneurysm 5 days after the first treatment. Because of the close proximity of the coil mass to the posterior inferior cerebellar artery (PICA) origin at first treatment, additional coil embolization by tight packing of the coil mass was planned. However, navigation of the microcatheter into the coil mass was challenging due to the tightly packed coil mass. Thus, a Marathon microcatheter, which has narrower outer diameter and is designed for liquid embolization, was used and successfully placed into the coil mass in an anterograde fashion. Thereafter, the DAC was advanced just proximal to the coil mass to reduce the kickback of the microcatheter during deployment of the coils and avoid the coil mass expansion toward the PICA origin, resulting in complete obliteration of the aneurysm with PICA preservation. Follow-up angiography performed 6 months after the second treatment showed complete obliteration of the aneurysm. The patient's course was uneventful after 1 year following the second treatment, with a modified Rankin Scale score of 1. Therefore, coil embolization through the tightly packed coil mass using a Marathon microcatheter is feasible. A low-profile DAC is also useful for enabling physicians to push the coil deployed through the flexible Marathon microcatheter.

Correlation Between Low-Density Hematoma at 1-Week Post-Middle Meningeal Artery Embolization and Rapid Resolution of Chronic Subdural Hematoma.

BACKGROUND: Temporal changes in the volume of chronic subdural hematoma (CSDH) following middle meningeal artery (MMA) embolization vary. We aimed to determine whether CSDH density on computed tomography is related to hematoma resolution following particle MMA embolization. METHODS: Patients who underwent MMA embolization for CSDH were enrolled. The CSDHs were quantitatively divided into 2 hematoma groups based on the hematoma density at 1-week postembolization: low-density or high-density. The temporal change in the volume of CSDHs was then analyzed between the groups. RESULTS: Thirty patients were enrolled in this study. Three patients with high-density hematomas required rescue surgery. The hematoma volume was significantly lower in low-density hematomas than in high-density hematoma at 1-week (P = 0.006), 1-month (P = 0.003), and 2-month (P = 0.004) postembolization; although the volume converged to a similar value at 3-month (P > 0.05). There was a positive correlation between hematoma density at 1-week postembolization and percentage hematoma volume at 1-week and 1-month postembolization (P = 0.004 and P < 0.001, respectively), but no correlation was observed between hematoma density before MMA embolization and percentage hematoma volume at 1-week and 1-month postembolization (P = 0.54 and P = 0.17, respectively). CONCLUSIONS: Rapid resolution of CSDH following MMA embolization was associated with low hematoma density at 1-week postembolization. Based on hematoma density on computed tomography at 1-week postembolization, a 1-month follow-up would be sufficient in cases of low density, but a 3-month follow-up would be required in cases of high-density hematoma. Larger studies and clinical trials are needed to confirm our findings.

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.

Endovascular embolization and needle aspiration of a life-threatening cervical hematoma due to a neurofibromatosis type 1-associated arteriovenous fistula: illustrative case.

BACKGROUND: In cases of neurofibromatosis in which the bleeding source is considered strongly related to a neurofibroma, an open surgical approach could risk uncontrollable bleeding from the vascular wall infiltration by neurofibroma. The case of a neurofibromatosis type 1 (NF1)-associated arteriovenous fistula presenting with a life-threatening cervical hematoma that was successfully treated with alternative treatment is described. OBSERVATIONS: A 68-year-old woman diagnosed with NF1 presented with sudden onset of a spontaneous right cervical mass. Neck imaging on admission showed a massive subcutaneous hematoma with tracheal deviation and abnormal vascular structure in the hematoma. Digital subtraction angiography showed that an arteriovenous fistula (AVF) fed from a vertebral artery located within the hematoma cavity was the primary source of bleeding and feeding arteries from the occipital artery to the neurofibroma. Embolization of the cervical neurofibroma, as well as the AVF, was performed to reduce the secondary risk of bleeding, and was accomplished. After endovascular treatment, needle aspiration of the cervical hematoma was performed to reduce the mass effect. LESSONS: When performing open surgery via tissues with neurofibromatosis proliferation, uncontrollable bleeding can occur. Therefore, endovascular embolization and needle aspiration of the hematoma should be considered in this setting.

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.

Transfemoral subclavian artery stenting through a shaped guiding catheter without pull-through technique: A case report.

Transfemoral subclavian artery stenting can be challenging unless the placement of the guiding catheter is secured. Herein, we present a patient with subclavian artery stenosis treated with endovascular stenting using a shaped guiding catheter. A 79-year-old woman was admitted to our department because of a cold sensation and numbness of her left arm. Computed tomography revealed stenosis of the left subclavian artery (SA), located just proximal to the ostium of the left vertebral artery (VA). Doppler ultrasound showed reverse flow in the left VA. We planned to stent for the SA stenosis under the balloon protection of the left VA. The balloon protection device was easily navigated into the left VA through brachial access. After that, a self-expandable stent was successfully placed from just proximal to the VA origin to the ostium of the SA using a highly stable shaped guiding catheter. The patient recovered from the symptoms and was discharged 4 days after the procedure. The high stability of the shaped guiding catheter is advantageous during endovascular treatment of the subclavian artery.

Balloon-hooking technique for stabilizing a guiding catheter in tortuous supra-aortic vessel: A case report.

Objective: When performing endovascular interventions for supra-aortic vessels, the tortuous vascular anatomy observed in patients with atherosclerotic lesions often limits the ability to maintain a stable guiding catheter position. Here, we report a case of right vertebral artery (VA) stenosis treated with transfemoral stenting and discuss the utility of balloon-hooking technique using partially inflated balloon for stabilizing the balloon guiding catheter (BCG) in the supra-aortic vessel. Case presentation: A 74-year-old man who underwent right carotid artery stenting, coronary artery bypass grafting, and bilateral iliac artery stenting was admitted to our emergency department because of dizziness related to head movement. Computed tomography angiography revealed right VA origin stenosis and left subclavian artery (SA) occlusion. The patient underwent stenting of the right VA. After several unsuccessful cannulation attempts into the right VA through transradial access, transfemoral access was obtained through the left iliac stent. A 9-Fr BGC was navigated into the right SA. The balloon was partially inflated just distal to the first curve of the right SA and used as hook by pulling back until the proximal edge of the balloon was pushed distally by the lesser curvature of the SA, resulting in stabilization of the BGC and successful angioplasty and stent deployment at the VA stenosis. The patient's symptoms resolved completely, without any neurological deficits. Conclusions: Balloon-hooking technique using a partially inflated BGC is feasible for stabilizing the guiding catheter in tortuous supra-aortic vessel.

Endovascular intervention for bilateral paramedian thalamic stroke due to occlusion of the unilateral P1 segment of the posterior cerebral artery: illustrative cases.

BACKGROUND: Occlusion of the unilateral P1 segment can result in bilateral paramedian thalamic infarction in patients with anatomical variants of the bilateral paramedian thalamic artery arising from a single P1 segment. Despite the life-threatening presentation of bilateral paramedian thalamic stroke, timely diagnosis is often challenging. OBSERVATIONS: The authors herein describe 3 patients treated with endovascular intervention for occlusion of the unilateral P1 segment wherein the bilateral paramedian thalamic arteries arose. All patients were admitted to the authors' emergency department with sudden-onset coma and respiratory distress; however, initial computed tomography was unremarkable. Despite suspicion of basilar artery occlusion, vertebral and carotid angiography revealed occlusion of the unilateral P1 segment. All patients were successfully treated with endovascular intervention. Overall, 2 patients had favorable outcomes (modified Rankin scale [mRS] scores of 0 and 1), whereas in 1 patient, the mRS score reached a baseline score of 3. LESSONS: In patients with the variant of the bilateral paramedian thalamic artery arising from a single P1 segment, occlusion of the unilateral P1 segment can be life threatening; nevertheless, timely endovascular treatment is effective. Carotid and vertebral angiography, rather than magnetic resonance or computed tomography angiography, is useful for immediate and reliable diagnosis of the relatively small vascular lesions.

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.

Drag-out technique using a large balloon fixed with an aspiration catheter for retrieving residual thrombus on the wall of the superior sagittal sinus: illustrative case.

BACKGROUND: The authors report a patient with sagittal sinus thrombosis that was resistant to reported endovascular treatments but successfully recanalized by dragging out the thrombus using a large balloon fixed with an aspiration catheter. OBSERVATIONS: A 57-year-old man presented with the persistent headache and a simple partial seizure. Diagnostic study with computed tomography and angiography demonstrated the superior sagittal sinus (SSS) thrombosis. Due to the neurological worsening even after systemic heparinization, the patient underwent mechanical thrombectomy. Despite six passes of stent retrievers and a large-bore aspiration catheter, functional recanalization was not achieved. Therefore, the so-called dental floss technique was attempted using a large compliant balloon catheter (Transform 7 × 7 mm). However, the balloon catheter just wobbled along the lesion without recanalization. To restrict the movement of the balloon catheter, the distal shaft of the balloon catheter was fixed with the aspiration catheter, and both the balloon and the aspiration catheter were slowly pulled to drag the thrombus out, resulting in recanalization of cortical veins as well as the SSS. LESSONS: Dragging the thrombus using a large balloon fixed with an aspiration catheter was a useful technique to retrieve sticky thrombus in the patients with the sinus thrombosis.

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.

Impact of external carotid artery occlusion at declamping of the external and common carotid arteries during carotid endarterectomy on development of new postoperative ischemic cerebral lesions.

OBJECTIVE: The external carotid artery (ECA) is inadvertently occluded during carotid endarterectomy (CEA). The importance of ECA occlusion has been emphasized as a loss of extracranial to intracranial collaterals, a source of chronic embolization, or a site for extended thrombosis during wound closure. This study aimed to determine whether ECA occlusion that inadvertently developed during endarterectomy and that was eventually detected using blood flow measurement of the ECA after declamping of all carotid arteries is a risk factor for development of new postoperative ischemic lesions at declamping of the ECA and common carotid artery (CCA) while clamping the internal carotid artery (ICA). This study also aimed to determine whether intraoperative transcranial Doppler (TCD) monitoring predicts the risk for development of such lesions. METHODS: This was a prospective observational study that included patients undergoing CEA for severe stenosis (≥70%) of the cervical ICA. When blood flow through the ECA measured using an electromagnetic flow meter decreased rapidly on clamping of only the ECA before carotid clamping for endarterectomy and was not changed by clamping of only the ECA after carotid declamping following endarterectomy, the patient was determined to have developed ECA occlusion. These patients underwent additional endarterectomy for the ECA. TCD monitoring in the ipsilateral middle cerebral artery was also performed throughout surgery to identify microembolic signals (MESs). Brain magnetic resonance diffusion-weighted imaging (DWI) was performed before and after surgery. RESULTS: There were 104 patients enrolled in the study. Eight patients developed ECA occlusion during surgery. The incidence of intraoperative ECA occlusion was significantly higher in patients without MESs at the phase of ECA and CCA declamping (8/12 [67%]) than in those with MESs (0/92 [0%]; P < .0001). Six patients exhibited new postoperative ischemic lesions on DWI. The incidence of intraoperative ECA occlusion (P < .0001) and the absence of MESs at declamping of the ECA and CCA while clamping the ICA (P <. 0001) were significantly higher in patients with development of new postoperative ischemic lesions on DWI than in those without. Sensitivity and specificity for the absence of MESs at declamping of the ECA and CCA while clamping the ICA for predicting development of new postoperative ischemic lesions on DWI were 100% (6/6) and 94% (92/98), respectively. CONCLUSIONS: ECA occlusion at declamping of the ECA and CCA while clamping the ICA during CEA is a risk factor for development of new postoperative ischemic lesions. Intraoperative TCD monitoring accurately predicts the risk for development of such lesions.

[123I-Iomazenil Single-Photon Emission Computed Tomography Imaging in a Patient with Mild Traumatic Subdural Hematoma Accompanied by Delayed Transient Aphasia].

Early and late images of 123I-iomazenil(IMZ)single-photon emission computed tomography(SPECT)reflect distributions of cerebral blood flow and those of cortical benzodiazepine receptor binding potential, respectively. Crossed cerebellar diaschisis reflects left-to-right asymmetry of metabolism in the cerebral hemispheres. We present a case of a 67-year-old woman who developed transient aphasia 3 days after the onset of a mild acute subdural hematoma. Computed tomography scan and magnetic resonance imaging during aphasia did not show enlargement of the hematoma or any new lesions. Electroencephalography did not show any abnormalities. Early images of 123I-IMZ SPECT 3 days after the onset of aphasia revealed a decrease in radioactivity in the right cerebellar hemisphere relative to that in the left cerebellar hemisphere. Late images of the same 123I-IMZ SPECT displayed a decrease in radioactivity in the left cerebral hemisphere relative to that in the right cerebral hemisphere. Twenty-four days later, the aphasia disappeared and the left-to-right asymmetries of radioactivity in the cerebellar and cerebral hemispheres on the early and late 123I-IMZ SPECT images also resolved.

Transient Symptomatic Downregulation of Cortical Neurotransmitter Receptor Function Due to Cerebral Hyperperfusion after Arterial Bypass Surgery for a Patient with Ischemic Moyamoya Disease.

Cerebral hyperperfusion syndrome following arterial bypass surgery is known as a surgical complication of moyamoya disease (MMD). How cerebral hyperperfusion affects neural function and causes neurological deficits remains unknown. We report here a case with cerebral hyperperfusion syndrome after arterial bypass surgery for ischemic MMD. Chronological changes of brain perfusion and central benzodiazepine receptor biding potential were observed using single-photon emission computed tomography. A 20-year-old woman with ischemic MMD underwent arterial bypass surgery. Six days later, cerebral hyperperfusion syndrome developed. During this syndrome, contralateral-to-ipsilateral cerebellar asymmetry of blood flow and a decrease in central benzodiazepine receptor binding potential in the area with hyperperfusion were observed. Four months later, these two findings resolved and a neurological examination revealed no abnormal signs. Cerebral hyperperfusion after arterial bypass surgery for ischemic MMD may lead to transient, reversible reduction of cerebral metabolism and downregulation of cortical neurotransmitter receptor function, resulting in transient neurological deficits.

Accuracy of brain perfusion single-photon emission computed tomography for detecting misery perfusion in adult patients with symptomatic ischemic moyamoya disease.

OBJECTIVE: The purpose of the present study was to determine how accurately relative cerebral blood flow (RCBF) and relative cerebrovascular reactivity (RCVR) to acetazolamide assessed using brain perfusion single-photon emission computed tomography (SPECT) detected misery perfusion identified on positron emission tomography (PET) in adult patients with ischemic moyamoya disease (MMD). METHODS: Oxygen extraction fraction (OEF), RCBF, and RCVR were assessed using 15O gas PET and N-isopropyl-p-[123I]-iodoamphetamine SPECT without and with acetazolamide challenge, respectively, in 45 patients. Regions of interest (ROIs) were automatically placed in the five middle cerebral artery (MCA) territories in the symptomatic cerebral hemisphere and in the ipsilateral cerebellar hemisphere using a three-dimensional stereotaxic ROI template. For RCBF and RCVR to acetazolamide, the ratio of the MCA ROI to cerebellar ROI was calculated. Of the five MCA ROIs in the symptomatic cerebral hemisphere in each patient, the ROI with the highest and lowest OEF value (two ROIs per patient) was selected for analyses. RESULTS: A significant square or linear correlation was observed between the OEF and RCBF (correlation coefficient, 0.780) or RCVR (correlation coefficient, - 0.345), respectively. The area under the receiver operating characteristic curve for detecting misery perfusion (OEF > 51.3%) was significantly greater for the RCBF than for the RCVR (difference between areas, 0.221; p < 0.0001). Sensitivity, specificity, and positive- and negative-predictive values for the RCBF for detecting misery perfusion were 100, 91, 67, and 100%, respectively. The specificity and positive-predictive value did not differ between the combination of the RCBF and RCVR and the CBF ratio alone. CONCLUSIONS: RCBF assessed using brain perfusion SPECT detects misery perfusion with high sensitivity, a high negative-predictive value, and a low positive-predictive value in adult patients with ischemic MMD. The accuracy of RCVR to acetazolamide assessed using brain perfusion SPECT is lower than that of RCBF.

Crossed Cerebellar Tracer Uptake on Acute-Stage 123I-Iomazenil SPECT Imaging Predicts 3-Month Functional Outcome in Patients With Nonfatal Hypertensive Putaminal or Thalamic Hemorrhage.

PURPOSE: Whereas SPECT images obtained 180 minutes after administration of I-iomazenil (IMZ) (late images) are proportional to the distribution of central benzodiazepine receptor-binding potential, SPECT images obtained within 30 minutes after I-IMZ administration (early images) correlate with regional brain perfusion. The aim of the present study was to determine whether crossed cerebellar tracer uptake on acute-stage I-IMZ SPECT imaging predicts 3-month functional outcome in patients with nonfatal hypertensive putaminal or thalamic hemorrhage. METHODS: Forty-six patients underwent early and late SPECT imaging with I-IMZ within 7 days after the onset of hemorrhage. A region of interest was automatically placed in the bilateral cerebellar hemispheres using a 3-dimensional stereotaxic region-of-interest template, and the ratio of the value in the cerebellar hemisphere contralateral to the affected side to that in the ipsilateral cerebellar hemisphere (ARcbl) was calculated in each patient. Each patient's physical function was measured using the modified Rankin scale (mRS) score 3 months after onset. RESULTS: The ARcbl on early (ρ = -0.511, P = 0.0003) and late (ρ = -0.714, P < 0.0001) images correlated with the mRS 3 months after the onset of hemorrhage. Multivariate analysis showed that only a low ARcbl in late images was significantly associated with a poor functional outcome (mRS score ≥3 at 3 months after onset) (95% confidence interval, 0.001-0.003; P = 0.0212). CONCLUSIONS: Crossed cerebellar tracer uptake on acute-stage I-IMZ SPECT imaging predicts 3-month functional outcome in patients with nonfatal hypertensive putaminal or thalamic hemorrhage.

Apparent diffusion coefficient and arterial spin labeling perfusion of conventional chondrosarcoma in the parafalcine region: a case report.

Intracranial chondrosarcoma is a very rare malignant tumor of the central nervous system, and is difficult to preoperatively distinguish from other tumors using conventional imaging techniques. Here, we report the case of a 24-year-old woman who presented with mild headache due to chondrosarcoma in the frontal lobe. Preoperative conventional images showed findings typical of an oligodendroglial tumor. However, high apparent diffusion coefficient (ADC) value and extreme hypoperfusion on arterial spin labeling (ASL) were inconsistent with oligodendroglial tumor characteristics. The tumor was completely removed using a standard surgical procedure. Histologic diagnosis was a conventional (classic) chondrosarcoma. High ADC and hypoperfusion on ASL represented low cellularity and low vascularity within conventional chondrosarcoma, respectively. We discuss the utility of ADC and ASL for the preoperative diagnosis of conventional chondrosarcoma.

Preoperatively reduced cerebrovascular contractile reactivity to hypocapnia by hyperventilation is associated with cerebral hyperperfusion syndrome after arterial bypass surgery for adult patients with cerebral misery perfusion due to ischemic moyamoya disease.

The present study examined whether preoperatively reduced cerebrovascular contractile reactivity to hypocapnia by hyperventilation is associated with development of cerebral hyperperfusion syndrome after arterial bypass surgery for adult patients with cerebral misery perfusion due to ischemic moyamoya disease. Among 65 adult patients with ischemic moyamoya disease, 19 had misery perfusion in the precentral region on preoperative 15O positron emission tomography and underwent arterial bypass surgery for that region. Brain technetium-99 m-labeled ethyl cysteinate dimer single-photon emission computed tomography (SPECT) was preoperatively performed with and without hyperventilation challenge and relative cerebrovascular contractile reactivity to hypocapnia (RCVCRhypocap) (%/mmHg) was calculated in the precentral region. Development of cerebral hyperperfusion syndrome was determined using perioperative changes of symptoms and brain N-isopropyl-p-[123I]-iodoamphetamine SPECT performed after surgery. RCVCRhypocap was significantly lower in the 6 patients with cerebral hyperperfusion syndrome (-2.85 ± 1.10%/mmHg) than in the 13 patients without cerebral hyperperfusion syndrome (0.18 ± 1.97%/mmHg; p = 0.0050). Multivariate analysis demonstrated low RCVCRhypocap as an independent predictor of cerebral hyperperfusion syndrome (95% confidence interval, 0.04-0.96; p = 0.0433). Preoperatively reduced cerebrovascular contractile reactivity to hypocapnia by hyperventilation is associated with development of cerebral hyperperfusion syndrome after arterial bypass surgery for adult patients with cerebral misery perfusion due to ischemic moyamoya disease.

Optimal Brain 99mTc-Ethyl Cysteinate Dimer SPECT Imaging and Analysis to Detect Misery Perfusion on 15O PET Imaging in Patients With Chronic Occlusive Disease of Unilateral Major Cerebral Artery.

PURPOSE: Misery perfusion is defined as marginally sufficient cerebral blood supply relative to cerebral metabolic demand. The aim of the present study was to determine the optimal brain Tc-ethyl cysteinate dimer (ECD) SPECT imaging and analysis to detect misery perfusion on O PET imaging in patients with chronic occlusive disease of unilateral internal carotid or middle cerebral artery (MCA). METHODS: For 97 patients, cerebral blood flow, cerebral metabolic rate of oxygen, and oxygen extraction fraction were measured using O PET; Tc-ECD SPECT was performed using dynamic scanning with a scan duration of 10 minutes each for 50 minutes after tracer administration. A region of interest was placed in the bilateral MCA territories and in the bilateral cerebellar hemispheres in all standardized images using a 3-dimensional stereotaxic region-of-interest template and affected-to-contralateral asymmetry ratio in the MCA territory (ARMCA) and contralateral-to-affected asymmetry ratio in the cerebellar hemisphere (ARcbl) were calculated. RESULTS: The ARMCA or ARcbl on Tc-ECD SPECT with a scan time of 20 to 30 minutes after tracer administration (ARMCA20-30 or ARcbl20-30) was correlated with ARMCA on PET cerebral blood flow (r = 0.654) or ARMCA on PET cerebral metabolic rate of oxygen (r = 0.576), respectively, more strongly than with other scan times. The area under the receiver operating characteristic curve for detecting abnormally elevated ARMCA on PET oxygen extraction fraction was significantly greater for ARcbl20-30/ARMCA20-30 (0.947) than for ARMCA20-30 alone (0.780) (difference between areas, 0.167; P = 0.0001) on Tc-ECD SPECT. CONCLUSIONS: Combination of asymmetries in the cerebellar and cerebral hemispheres on Tc-ECD SPECT in a scan time of 20 to 30 minutes after tracer administration optimally detects misery perfusion in unilateral internal carotid artery or MCA occlusive disease.