Characterization of carotid plaques using chemical exchange saturation transfer imaging.

PURPOSE: The preoperative assessment of carotid plaques is necessary to render revascularization safe and effective. The aim of this study is to evaluate the usefulness of chemical exchange saturation transfer (CEST)-MRI, particularly amide proton transfer (APT) imaging as a preoperative carotid plaque diagnostic tool. METHODS: We recorded the APT signal intensity on concentration maps of 34 patients scheduled for carotid endarterectomy. Plaques were categorized into group A (APT signal intensity ≥ 1.90 E-04; n = 12) and group B (APT signal intensity < 1.90 E-04; n = 22). Excised plaques were subjected to histopathological assessment and, using the classification promulgated by the American Heart Association, they were classified as intraplaque hemorrhage-positive [type VI-positive (tVI+)] and -negative [no intraplaque hemorrhage (tVI-)]. RESULTS: Of the 34 patients, 22 (64.7%) harbored tVI+- and 12 (35.3%) had tVI- plaques. The median APT signals were significantly higher in tVI+- than tIVI- patients (2.43 E-04 (IQR = 0.98-4.00 E-04) vs 0.54 E-04 (IQR = 0.14-1.09 E-04), p < .001). Histopathologically, the number of patients with tVI+ plaques was significantly greater in group A (100%, n = 12) than group B (45%, n = 22) (p < .01). The number of symptomatic patients or asymptomatic patients with worsening stenosis was also significantly greater in group A than group B (75% vs 36%, p < .01). CONCLUSION: In unstable plaques with intraplaque hemorrhage and in patients with symptoms or progressive stenosis, the ATP signals were significantly elevated. CEST-MRI studies has the potential for the preoperative assessment of the plaques' characteristics.

Utility of Lean Body Mass Equations and Body Mass Index for Predicting Outcomes in Critically Ill Adults with Sepsis: A Retrospective Study.

Lean body mass is a significant component of survival from sepsis. Several equations can be used for calculating lean body mass based on age, sex, body weight, and height. We hypothesized that lean body mass is a better predictor of outcomes than the body mass index (BMI). This study used a multicenter cohort study database. The inclusion criteria were age ≥18 years and a diagnosis of sepsis or septic shock. BMI was classified into four categories: underweight (<18.5 kg/m2), normal (≥18.5-<25 kg/m2), overweight (≥25-<30 kg/m2), and obese (≥30 kg/m2). Four lean body mass equations were used and categorized on the basis of quartiles. The outcome was in-hospital mortality among different BMI and lean body mass groups. Among 85,558 patients, 3916 with sepsis were included in the analysis. Regarding BMI, in-hospital mortality was 36.9%, 29.8%, 26.7%, and 27.9% in patients who were underweight, normal weight, overweight, and obese, respectively (p < 0.01). High lean body mass did not show decreased mortality in all four equations. In critically ill patients with sepsis, BMI was a better predictor of in-hospital mortality than the lean body mass equation at intensive care unit (ICU) admission. To precisely predict in-hospital mortality, ICU-specific lean body mass equations are needed.

Coexistence of anterior choroidal artery and posterior cerebral artery retia mirabilia presenting with subarachnoid hemorrhage: illustrative case.

BACKGROUND: A rete mirabile is a rare vascular anomaly, with posterior cerebral artery (PCA) involvement being especially rare. Its pathogenesis has been speculated as a remnant of "distal annexation" between the primitive anterior choroidal artery (AchA) and the PCA at this site, but the exact mechanisms remain unclear. OBSERVATIONS: A 29-year-old man presented with subarachnoid hemorrhage. Arteriovenous malformation in the medial temporal lobe was initially suspected, but an arteriovenous shunt was not detected. First, conservative treatment was administered; however, rebleeding occurred 1 month later. Carotid angiography revealed a network-like cluster of blood vessels at the choroidal point of the AchA, suggesting a rete mirabile; these vessel clusters led to the persistent temporo-occipital branch of the AchA. Furthermore, an aneurysm was detected at the junction between the rete mirabile and the persistent temporo-occipital branch of the AchA. Additionally, vertebral angiography demonstrated a rete mirabile at the P2 segment. These findings suggested the coexistence of AchA and PCA retia mirabilia. Consequently, the aneurysm was clipped using a subtemporal approach to prevent re-rupture, and the postoperative course was uneventful. LESSONS: This first report of coexisting AchA and PCA retia mirabilia supports the remnant of distal annexation between the primitive AchA and the PCA as the reason for rete formation at this site.

Evaluation of Serial Intra-Arterial Indocyanine Green Videoangiography in the Surgical Treatment of Cranial and Craniocervical Junction Arteriovenous Fistulae: A Case Series.

BACKGROUND AND OBJECTIVES: Intravenous indocyanine green (IV-ICG) videoangiography is commonly performed to detect blood flow in the microscopic view. However, intra-arterial ICG (IA-ICG) videoangiography provides high-contrast imaging, repeatability within a short period of time, and clear-cut separation of the arterial and venous phases compared with IV-ICG. These features are useful for detecting retrograde venous drainage (RVD) and shunt occlusion in arteriovenous fistulae (AVF) surgery. This study aimed to investigate whether IA-ICG videoangiography can be repeatable within a short period of time and be useful for detecting RVD and shunt occlusion in cranial- and craniocervical junction (CCJ)-AVF surgery. METHODS: Between January 2012 and December 2022, 50 patients were treated with endovascular or surgical intervention for cranial- and CCJ-AVF at Tokushima University Hospital. Of these, 5 patients (6 lesions) underwent open surgery with IA-ICG videoangiography in a hybrid operating room. We analyzed the data of these 5 patients (6 lesions). RESULTS: There were 4/patient (median, range 2-12) and 3.5/lesion (median, range 2-10) intraoperative IA-ICG runs. IA-ICG videoangiography detected RVD in all patients. Clearance of IA-ICG-induced fluorescence was achieved within 30 seconds in all patients at each region of interest. After the disconnection of the fistulae, IA-ICG videoangiography and intraoperative digital subtraction angiography (DSA) confirmed the disappearance of RVD in all patients. There were no complications associated with IA-ICG videoangiography. CONCLUSION: This study showed that IA-ICG videoangiography is repeatable within a short period of time before and after obliteration and can be useful for detecting RVD and shunt occlusion in cranial- and CCJ-AVF surgery. IA-ICG videoangiography also allows intraoperative DSA studies in a hybrid operating room. Considering the recent advancements in hybrid operating rooms, combining IA-ICG videoangiography with intraoperative DSA is a useful strategy for cranial- and CCJ-AVF surgery.

Prognostic factors for acute large vessel occlusion with NIHSS 5 or lower.

BACKGROUND: Intravenous recombinant tissue plasminogen activator (IV rt-PA) and endovascular treatment have been performed for severe large vessel occlusion (LVO) and the results have been reported at high levels of evidence. However, acute treatment for LVO with mild symptom remains controversial. We retrospectively examined prognostic factors for LVO with mild symptoms. METHOD: We studied retrospectively the patients within 24 h of onset with large vessel occlusion with NIHSS score ??5. Outcomes were evaluated by modified Rankin Scale (mRS) at 90 days, with 0?2 defined as a good outcome and 3?6 as a poor outcome. Clinical characteristics of each case were examined. RESULT: Participants comprised 76 patients. Of the 76 patients. ICA occlusion showed good outcome in 17?/?19 cases (90%), whereas MCA occlusion showed good outcome in 36?/?54 cases (67%). Among the 14 cases showing positive results for distal intraarterial signal (d-IAS), outcomes were good in 6 cases (43%). On the other hand, the 32 d-IAS-negative cases showed good outcome in 28 cases (88%). Outcomes were thus significantly poorer for d-IAS-positive cases. CONCLUSION: MCA occlusion is associated with poor prognosis, even with NIHSS score ??5, and d-IAS may provide a predictor. J. Med. Invest. 70 : 22-27, February, 2023.

Repetitive postoperative extubation failure due to dynamic inspiratory airway collapse concomitant with subglottic stenosis in a patient who previously underwent tracheostomy.

BACKGROUND: This report describes a case of dynamic inspiratory airway collapse concomitant with subglottic stenosis in a patient who previously underwent tracheostomy that led to repeated post-operative extubation failure. CASE PRESENTATION: A 43-year-old woman who had undergone tracheostomy 25 years previously was admitted to our intensive-care unit (ICU) after coronary artery bypass graft surgery. On postoperative day (POD) 0, she was extubated, but stridor was observed. We suspected upper airway obstruction and she was therefore reintubated. Before reintubation, urgent laryngotracheoscopy revealed dynamic inspiratory airway collapse and obstruction concomitant with subglottic stenosis. Preoperative computed tomography showed mild subglottic stenosis. Although intravenous corticosteroids were administered to prevent tracheal mucosal edema and a cuff leak test was confirmed to be negative, she developed extubation failure on POD6. On POD12, we performed tracheostomy to reduce mechanical irritation from the endotracheal tube. Mechanical ventilation was withdrawn and she discharged from the ICU. On POD33, her tracheostomy tube was removed and she remained clinically asymptomatic. CONCLUSIONS: We should be aware of the history of tracheostomy, especially at high tracheostomy sites, even in the absence of respiratory symptoms as risk factors for dynamic inspiratory airway collapse concomitant with subglottic stenosis contributing to repeated respiratory failure after extubation. J. Med. Invest. 70 : 301-305, February, 2023.

Acquired laryngomalacia as a cause of post-extubation respiratory failure in patient with postoperative seizure and central pontine myelinolysis after craniotomy.

Background : Laryngomalacia is a congenital abnormality of the larynx that commonly occurs in children and rarely in adults. We report the first case of acquired laryngomalacia mainly due to postoperative seizure and central pontine myelinolysis after scheduled craniotomy. Case presentation : A 69-year-old man was admitted to the hospital for elective craniotomy for craniopharyngioma. After the surgery, he developed refractory seizure and required intubation and mechanical ventilation in the intensive-care unit (ICU). After treatment for the seizure, he was extubated. However, immediately after extubation, he developed stridor and respiratory retraction. We performed fiberoptic laryngoscopy and confirmed that the epiglottis had collapsed into the posterior wall of the pharynx during inspiration, which was suspected to be laryngomalacia. He received invasive mechanical ventilation for two days following re-extubation. After the second extubation, he developed stridor again due to acquired laryngomalacia. Six days later, his respiratory condition had worsened, and he received re-intubation and tracheostomy. After ICU discharge, central pontine myelinolysis was diagnosed by magnetic resonance imaging. Conclusions : Adult-onset laryngomalacia is a rare cause of upper airway obstruction but should be considered as a cause of postoperative extubation failure. We should not delay performing fiberoptic laryngoscopy to evaluate this pathology and provide optimal treatment. J. Med. Invest. 69 : 316-319, August, 2022.

Independent lung ventilation for the management of acute allograft rejection after single-lung transplantation for end-stage emphysema.

Background : We herein report the use of independent lung ventilation (ILV) for managing acute allograft rejection after single-lung transplantation (SLT) for end-stage emphysema. Case presentation : A 54-year-old woman was transferred to our hospital with severe hypoxemia and respiratory distress due to unilateral lung disease with diffuse alveolar damage in the right donor lung associated with acute allograft rejection and with hyperinflation of the left native lung due to emphysema. She was unresponsive to immunosuppressive medications and conventional ventilation strategies, so different ventilator settings for each lung were required. A double-lumen endotracheal tube (DLT) was inserted, and ILV was initiated. The right lung was ventilated with high positive end-expiratory pressure (PEEP), intended for lung recruitment, and the left lung was ventilated with lung protective strategies using a low tidal volume and low levels of PEEP to avoid hyperinflation. Two days later, her lung function was dramatically improved, and the DLT was replaced with a single-lumen endotracheal tube. Gas exchange was maintained, and she was successfully weaned from mechanical ventilation on intensive-care unit day 15. Conclusions : ILV appears to be effective and safe for managing acute allograft rejection after SLT for emphysema. J. Med. Invest. 69 : 323-327, August, 2022.

Relationships between double cycling and inspiratory effort with diaphragm thickness during the early phase of mechanical ventilation: A prospective observational study.

BACKGROUND: Increased and decreased diaphragm thickness during mechanical ventilation is associated with poor outcomes. Some types of patient-ventilator asynchrony theoretically cause myotrauma of the diaphragm. However, the effects of double cycling on structural changes in the diaphragm have not been previously evaluated. Hence, this study aimed to investigate the relationship between double cycling during the early phase of mechanical ventilation and changes in diaphragm thickness, and the involvement of inspiratory effort in the occurrence of double cycling. METHODS: We evaluated adult patients receiving invasive mechanical ventilation for more than 48 h. The end-expiratory diaphragm thickness (Tdiee) was assessed via ultrasonography on days 1, 2, 3, 5 and 7 after the initiation of mechanical ventilation. Then, the maximum rate of change from day 1 (ΔTdiee%) was evaluated. Concurrently, we recorded esophageal pressure and airway pressure on days 1, 2 and 3 for 1 h during spontaneous breathing. Then, the waveforms were retrospectively analyzed to calculate the incidence of double cycling (double cycling index) and inspiratory esophageal pressure swing (ΔPes). Finally, the correlation between double cycling index as well as ΔPes and ΔTdiee% was investigated using linear regression models. RESULTS: In total, 19 patients with a median age of 69 (interquartile range: 65-78) years were enrolled in this study, and all received pressure assist-control ventilation. The Tdiee increased by more than 10% from baseline in nine patients, decreased by more than 10% in nine and remained unchanged in one. The double cycling indexes on days 1, 2 and 3 were 2.2%, 1.3% and 4.5%, respectively. There was a linear correlation between the double cycling index on day 3 and ΔTdiee% (R2 = 0.446, p = 0.002). The double cycling index was correlated with the ΔPes on days 2 (R2 = 0.319, p = 0.004) and 3 (R2 = 0.635, p < 0.001). CONCLUSIONS: Double cycling on the third day of mechanical ventilation was associated with strong inspiratory efforts and, possibly, changes in diaphragm thickness.

Single-session hematoma removal and transcortical venous approach for coil embolization of an isolated transverse-sigmoid sinus dural arteriovenous fistula in a hybrid operating room: illustrative case.

BACKGROUND: Dural arteriovenous fistula (DAVF) can present with massive hematoma, which sometimes requires emergent removal. Therefore, a surgical strategy for single-session hematoma removal and shunt occlusion in the same surgical field is important. OBSERVATIONS: A 73-year-old man was transferred to the authors' hospital with a headache. Brain computed tomography (CT) revealed an intracerebral hematoma in the right temporoparietal lobe (hematoma volume 12 ml). A cerebral angiogram revealed a right isolated transverse-sigmoid sinus (TSS)-DAVF fed by the occipital artery and middle meningeal artery. There was cortical venous reflux into the Labbé vein and posterior parietal vein. Percutaneous transarterial and transvenous embolization were unsuccessful. The following day, his consciousness level acutely declined with a headache, and brain CT showed hematoma expansion (hematoma volume 41 ml) with a midline shift. Therefore, the authors performed single-session hematoma removal and a transcortical venous approach for coil embolization of an isolated TSS-DAVF in a hybrid operating room. His postoperative course was uneventful. No recurrence was observed 3 months postoperatively on cerebral angiography. LESSONS: Single-session hematoma removal and a transcortical venous approach for coil embolization of an isolated TSS-DAVF is considered in cases with massive hematoma. This strategy is useful, considering recent developments in hybrid operating rooms.

The claw sign predicts first-pass effect in mechanical thrombectomy for cerebral large vessel occlusion in the anterior circulation.

BACKGROUND: Mechanical thrombectomy (MT) is an effective treatment for acute cerebral large vessel occlusion (LVO). Complete recanalization of vessels in a single procedure is defined as the first-pass effect (FPE) and is associated with good prognosis. In this study, angiographic clot protruding sign termed the "claw sign," was examined as candidate preoperative imaging factor for predicting the FPE. METHODS: We retrospectively analyzed data from 91 consecutive patients treated for acute LVO in the anterior circulation by MT between January 2014 and December 2019. The claw sign was defined as a thrombus that protruded proximally by more than half of the diameter of the parent artery. Radiological findings such as claw sign, clinical and etiological features, and outcomes were compared between groups with and without successful FPE. Multivariate analysis was conducted to evaluate perioperative factors associated with FPE. RESULTS: FPE was achieved in 26 of 91 (28.6%) patients and the claw sign was observed in 34 of 91 (37.4%) patients. The claw sign was significantly more frequent in the successful FPE group than in the failed FPE group (53.8% vs. 30.8%; P = 0.040). After the multivariate analysis, the claw sign was the only pretreatment parameter that could predict FPE (odds ratio, 2.67; 95% confidence interval, 1.01-7.06; P = 0.047). CONCLUSION: The claw sign is an angiographic imaging factor that might predict FPE after MT for anterior circulation acute ischemic stroke.

Chronic subdural hematoma associated with dural metastasis leads to early recurrence and death: A single-institute, retrospective cohort study.

The prevalence of chronic subdural hematoma (CSDH) associated with dural metastasis is uncertain, and appropriate treatment strategies have not been established. This study aimed to investigate the characteristics of and appropriate treatment strategies for CSDH associated with dural metastasis. We retrospectively reviewed the charts of 214 patients who underwent surgery for CSDH. The patients were divided into the dural metastasis group (DMG; n = 5, 2.3%) and no dural metastasis group (No-DMG; n = 209, 97.3%). Patient characteristics, treatment, and outcomes were compared between the two groups. Active cancer was detected in 31 out of 214 patients, 5 of whom (16.1%) had dural metastasis. In-hospital death (80.0% vs. 0%; p < 0.001) and recurrence within 14 days (80.0% vs. 2.9%; p < 0.001) and 60 days (80.0% vs. 13.9%; p = 0.002) were significantly prevalent in the DMG. All patients in the DMG developed subdural hematoma re-accumulation requiring emergent surgery because of brain herniation, and patients in the DMG had significantly worse recurrence-free survival (p < 0.001). This relationship remained significant (p < 0.001) even when the analysis was limited to the active cancer cohort (n = 31). CSDH associated with dural metastasis leads to early recurrence and death because of the difficulty in controlling subdural hematoma re-accumulation by common drainage procedures. Depending on the primary cancer status, withdrawal of active treatment and change to palliative care should be discussed after diagnosing CSDH associated with dural metastasis.

Involvement of Neutrophil Extracellular Traps in Cerebral Arteriovenous Malformations.

BACKGROUND: Cerebral arteriovenous malformations (cAVMs) represent tangles of abnormal vasculature without intervening capillaries. High-pressure vascular channels due to abnormal arterial and venous shunts can lead to rupture. Multiple pathways are involved in the pathobiology of cAVMs including inflammation and genetic factors such as KRAS mutations. Neutrophil release of nuclear chromatin, known as neutrophil extracellular traps (NETs), plays a multifunctional role in infection, inflammation, thrombosis, intracranial aneurysms, and tumor progression. However, the relationship between NETs and the pathobiology of cAVMs remains unknown. We tested whether NETs play a role in the pathobiology of cAVMs. METHODS: We analyzed samples from patients who had undergone surgery for cAVM and immunohistochemically investigated expression of citrullinated histone H3 (CitH3) as a marker of NETs. CitH3 expression was compared among samples from cAVM patients, epilepsy patients, and normal human brain tissue. Expressions of thrombotic and inflammatory markers were also examined immunohistochemically in samples from cAVM patients. RESULTS: Expression of CitH3 derived from neutrophils was observed intravascularly in all cAVM samples but not other samples. Nidi of AVMs showed migration of many Iba-I-positive cells adjacent to the endothelium and endothelial COX2 expression, accompanied by expression of IL-6 and IL-8 in the endothelium and intravascular neutrophils. Unexpectedly, expression of CitH3 was not necessarily localized to the vascular wall and thrombus. CONCLUSIONS: Our results offer the first evidence of intravascular expression of NETs, which might be associated with vascular inflammation in cAVMs.

Elevated Urinary Titin and its Associated Clinical Outcomes after Acute Stroke.

INTRODUCTION: Urinary titin is a biomarker of muscle atrophy, which is a serious complication after stroke. However, there are currently no clinical data regarding urinary titin in stroke patients. METHODS: Consecutive stroke patients admitted to the stroke care unit were included. Spot urine samples were collected immediately after admission, and on days 3, 5, and 7. The primary outcome was the trend of urinary titin in patients after acute stroke. The secondary outcomes included the association between the peak urinary titin level and the modified Rankin Scale (mRS) score, the National Institutes of Health Stroke Scale (NIHSS) score, and the Barthel index (BI) upon hospital discharge. Multivariate analysis was adjusted for age, sex, NIHSS at admission, and the peak urinary titin to predict poor outcome (mRS 3-6). RESULTS: Forty-one patients were included (29 male; age, 68 ± 15 years), 29 had ischemic stroke, 8 had intracerebral hemorrhage, and 4 had subarachnoid hemorrhage. The levels of urinary titin on days 1, 3, 5, and 7 were 9.9 (4.7-21.1), 16.2 (8.6-22.0), 8.9 (4.8-15.2), and 8.7 (3.6-16.2) pmol/mg Cr, respectively. The peak urinary titin level was associated with the mRS score (r = 0.55, p < 0.01), the NIHSS score (r = 0.72, p < 0.01), and the BI (r = -0.59, p < 0.01) upon hospital discharge. In multivariate analysis, the peak urinary titin was associated with poor outcome (p = 0.03). CONCLUSIONS: Urinary titin rapidly increased after stroke and was associated with impaired functional outcomes at hospital discharge.

Improvement of Hemifacial Spasm after Stent-assisted Coil Embolization for Ipsilateral Vertebral Artery Dissecting Aneurysm.

Microvascular decompression (MVD) is the gold standard in the treatment of hemifacial spasm (HFS), and endovascular surgery has been described as a treatment only for aneurysm-induced HFS in several previous cases. We describe symptomatic HFS caused by a normal vertebral artery (VA) trunk adjacent to the ipsilateral dissecting VA aneurysm completely cured after stent-assisted coil embolization. A 52-year-old man presented with a 2-month history of gradually worsening left HFS. Magnetic resonance imaging (MRI) and cerebral angiography revealed a dissecting VA aneurysm on the left side. Based on the findings from preoperative MRI, not the aneurysmal dome itself, but the VA trunk just distal to the aneurysmal dome was considered likely to be compressing the root exit zone (REZ) of the facial nerve. Stent-assisted coil embolization was conducted for the VA aneurysm, and the stent was deployed to cover the wide neck of the aneurysm and offending zone of the VA trunk simultaneously. HFS started to show improvement just after the procedure and complete disappearance within 1 year. HFS was completely resolved by stenting of the offending artery. Stents may show efficacy for "intra-arterial decompression" by reducing pulsatility against the REZ of the facial nerve due to the thickness and rigidity of the stent metal and delayed endothelialization.

Gelatin-thrombin Hemostatic Matrix-related Cyst Formation after Cerebral Hematoma Evacuation: A Report of Two Cases.

The gelatin-thrombin matrix, Floseal, is an excellent novel hemostatic agent that is used in various surgical fields. Thrombin is a serine protease, and the conversion of prothrombin to thrombin is an essential step in the coagulation cascade. However, thrombin can induce blood-brain barrier (BBB) disruption and vasogenic brain edema. This report describes two cases of gelatin-thrombin matrix-related cyst formation after cerebral hematoma evacuation. An 82-year-old man with a gelatin-thrombin matrix-related cyst was treated by cyst drainage and fenestration to the lateral ventricle. Histological evaluation of the cyst wall showed a gelatin-thrombin matrix reserve, marked infiltration of inflammatory cells, and foam cell accumulation. In addition, an 85-year-old woman with a gelatin-thrombin matrix-related cyst was treated with steroids and responded well. In both cases, the post-treatment course was uneventful. Cyst shrinkage and no recurrence were observed. The gelatin-thrombin matrix can cause cyst formation with brain edema. This is the first report demonstrating the cyst wall pathology and the steroid responsivity on cyst shrinkage. The mechanism of cyst formation is thought to be thrombin-induced BBB disruption. Excess gelatin-thrombin matrix should be carefully removed from the surgical beds, particularly those having a blinded space from the neurosurgical microscope.

Effect of High-Flow Nasal Cannula on Sleep-disordered Breathing and Sleep Quality in Patients With Acute Stroke.

Introduction Sleep-disordered breathing (SDB) is common after stroke. Although the standard treatment of SDB is continuous positive airway pressure (CPAP) ventilation, the patient's intolerance and discomfort result in low adherence rates. Alternatively, high-flow nasal cannula (HFNC) may be useful as it reduces upper airway collapse with low level of positive pressure and well tolerability. The aim of this study was to investigate whether HFNC therapy reduces SDB and improves sleep quality with higher compliance rate. Methods We included acute stroke patients with SDB for the assessment of apnea-hypopnea index (AHI) >5/h using WatchPAT 200 (Itamar Medical Ltd, Caesarea, Israel). Patients who met inclusion criteria received HFNC therapy (40 L/min) with monitoring by WatchPAT. AHI, oxygen desaturation index (ODI), sleep efficiency, and rapid eye movement (REM) sleep were compared in patients with and without HFNC therapy. We also evaluated the patient's comfort of HFNC therapy (discomfort or not). Results Among 17 patients assessed for AHI, 12 received HFNC therapy. HFNC therapy was not adhered in two patients due to intolerance. Eight patients remained for final analysis. There were no differences in SDB and sleep quality with and without HFNC therapy as follows: HFNC therapy vs control; AHI 24.9 ± 20.1 vs 21.3 ± 15.0/h (p = 0.63), ODI 16.2 ± 16.5 vs 12.9 ± 12.3/h (p = 0.54), sleep efficiency 80.4 ± 12.9 vs 87.1 ± 6.2 (p = 0.28), percentage of REM sleep 19.4% ± 9.6% vs 27.6% ± 8.9% (p = 0.07). Two patients (17%) complained of discomfort among eight patients. Conclusion HFNC therapy did not improve SDB and sleep quality. Nonadherence and discomfort were observed in HFNC therapy. We need a large trial to confirm this result.

Cone beam-computed tomography angiography by intravenous contrast injection is reliable to evaluate patients with large vessel occlusion.

PURPOSE: Mechanical thrombectomy (MT) for acute ischemic stroke (AIS) patients due to emergent large vessel occlusion (ELVO) is standard treatment, the benefits, however, are highly time-sensitive. After patient eligibility for reperfusion therapy is determined by conventional radiological examinations, the time to be transferred from the department of radiological examination to angiography-suites is critical. We speculated that the time required for the diagnosis of AIS might be reduced if we could determine MT eligibility in patients with ELVO at angiography-suites. Modern angiography-suites with flat panel detectors can perform cone beam (CB)-CT. We performed CB-CTA using intravenous injection of contrast agent to evaluate occlusion sites, collateral score, and construction of vessels distal to occlusion sites and determined if CB-CTA could be useful to evaluate patients with ELVO. METHODS: We included 15 patients with ELVO diagnosed by conventional MRI or CT/CTA, and investigated whether CB-CTA was reliable to diagnose occlusion sites. We also studied if collateral score on CB-CTA was associated with prognosis after successful reperfusion by MT by comparison between favorable (modified Rankin scale (mRS) 0-2), and unfavorable outcome group (mRS 3-6). RESULTS: There was strong agreement of occlusion sites between CB-CTA and conventional radiological examination (κ = 0.80). Collateral score determined by CB-CTA was significantly different between favorable outcome and unfavorable outcome group (median collateral score 2.3 v.s. 1.3, p = 0.040). CONCLUSIONS: Although prospective study of AIS patients at a radiography department is indispensable, CB-CTA performed in an angiography-suite might be useful to evaluate patients with ELVO.

[A Case of Spontaneous Intracranial Hypotension Successfully Treated with Repetitive Epidural Blood Patch after Warfarin Reversal].

We report a case of spontaneous intracranial hypotension successfully treated with repetitive epidural blood patch after warfarin reversal. A 75-year-old man presented with a 2-week history of headache. He was being treated with warfarin for atrial fibrillation. Neurological examination on admission showed mild disorientation. Prothrombin time-international normalized ratio(PT-INR)was elevated to 2.43. Initial magnetic resonance images of the brain demonstrated bilateral subdural hematomas, distortion of midbrain and diffuse pachymeningeal enhancement. Conservative treatments with bed rest and hydration were administered. On the third posthospital day, he became lethargic and emergently underwent epidural blood patch(EBP)at lumbar level. Consciousness disturbance improved immediately but reappeared 12 hours after the EBP. The second EBP was performed but consciousness level decreased again 12 hours later. The effect of warfarin was reversed by administration of vitamin K and fresh frozen plasma before the third EBP. After the procedure, he became alert. The findings of neurological examination did not change but a CT on day 12 revealed increase in volume of left-sided subdural hematoma. He underwent EBP and evacuation of hematoma. The neurological findings remained unchanged. A CT on the 17th posthospital day showed increase of right-sided subdural hematoma, and EBP and evacuation of hematoma were then performed. After the 5th EBP, the clinical course was uneventful. Predictors for successful EBP are not fully clarified. In patients who undergo anticoagulation therapy, EBP may be ineffective and normalization of coagulability required.

Plaque Characteristics of Patients with Symptomatic Mild Carotid Artery Stenosis.

BACKGROUND: Carotid revascularization may be considered for severe stenosis, but its use for symptomatic mild stenosis (<50%) with vulnerable plaque or ulcer remains uncertain. The characteristics of patients with symptomatic mild stenosis who underwent revascularization are reviewed. METHODS: The subjects of this study were 18 patients with symptomatic mild stenosis (<50%) on angiography from among 175 patients who underwent revascularization in our department. The plaques were evaluated by black-blood magnetic resonance imaging (BB-MRI) and ultrasonography (US) and classified into 2 types: type 1 (n = 15), a lesion with an ulcer or mobile plaque or thrombosis on angiography or US; and type 2 (n = 3), a lesion without any of the above. Fourteen patients underwent carotid endarterectomy (CEA), and 4 patients underwent carotid artery stenting. RESULTS: The stenosis on angiography was 27.2% ± 10.7 (5%-41%), and the area carotid artery stenosis rate on US was 69.8 ± 14.5% (44.5%-97%). The stenosis rate of these 2 methods was not at all correlated. In type 1 plaque that underwent CEA, 10 of 11 patients had vulnerable plaque by histopathology, and 1 patient had thrombus on the plaque by operative findings. In type 2 plaque that underwent CEA, all patients had vulnerable plaque by histopathology. During the follow-up period, none of the patients had restenosis or stroke. CONCLUSIONS: The findings of US and BB-MRI in patients with symptomatic mild stenosis (<50%) on angiography are important for determining treatment. If BB-MRI or US shows the findings of vulnerable plaque in mild stenosis, surgical treatment may be considered for these patients.