Frailty and Humoral Immune Responses Following COVID-19 Vaccination among Patients Undergoing Hemodialysis.

BACKGROUND: Patients with end-stage kidney disease who are undergoing dialysis have reduced immune responses to COVID-19 vaccination. Frailty is extremely common among dialysis patients and may contribute to the impaired immunogenicity. This study aimed to determine the association between frailty and humoral immune responses following COVID-19 vaccination in hemodialysis patients. DESIGN, SETTING, PARTICIPANTS: Adult hemodialysis patients without prior SARS-CoV-2 infection who received a priming dose of ChAdOx1 nCoV-19, an adenovirus-vectored vaccine, were assessed for eligibility. Participants were categorized as robust, pre-frail, or frail using the Fried frailty criteria. Humoral responses were assessed 28 days after vaccination by measuring titers of anti-spike IgG antibodies. The primary outcome was anti-spike antibody seroconversion, defined as antibody levels ≥50 AU/mL. Multivariable-adjusted logistic regression models were used to assess the association between frailty status and the primary outcome. RESULTS: A total of 206 participants (mean age 67 ± 13 years, 50% women) were included in the study, of whom 50 (24%) were characterized as frail, 86 (42%) were characterized as pre-frail, and 70 (34%) were characterized as robust. Anti-spike antibody levels were progressively lower with more advanced stages of frailty (P <0.001). Compared with robust patients, a significantly smaller proportion of pre-frail and frail patients developed anti-spike antibody seroconversion (87%, 66%, and 40%, respectively; P <0.001). Frailty was associated with the absence of humoral responses after adjustment for age, sex, body mass index, diabetes, coronary artery disease, serum albumin, and lymphocyte count (OR=0.25; 95% CI, 0.08-0.80). CONCLUSIONS: Frailty is independently associated with impaired humoral responses following COVID-19 vaccination among hemodialysis patients. Strategies aimed at preventing or attenuating frailty in the dialysis population are warranted.

Infective Endocarditis Presented as Acute Pyelonephritis: A Case Report

ABSTRACT Infective endocarditis is less likely to sparkle out preferentially in our minds when evaluating and making differential diagnosis of patients with fever daily in emergency departments. We describe a case of infective endocarditis. He was initially diagnosed with pyelonephritis of the right kidney at a hospital because of the noted right flank knocking pain. His computed tomography showed two wedge-shaped low-density lesions in the spleen and the right kidney separately. It dropped a hint to the emergency department physician of thinking of the feature of infarct. The previously neglected cardiac murmurs were then an important clue. We then performed transthoracic emergent echocardiography and confirmed the diagnosis of infective endocarditis.

Engorgement of Deep Medullary Veins in Neurosarcoidosis: A Common-Yet-Underrecognized Cerebrovascular Finding on SWI.

We describe the prevalence and potential significance of deep medullary vein engorgement on SWI in patients with neurosarcoidosis, a finding that has not been described previously. Engorgement was evaluated for possible associations with meningeal or perivascular disease, intracranial hemorrhage, and venous thrombosis, as well as with modified Rankin Scale scores at the time of MR imaging and at follow-up. Deep medullary vein engorgement was seen in 7 of 21 patients and was more common in men. Patients with venous engorgement had a significantly increased incidence of microhemorrhages, perivascular disease, and hydrocephalus. There was no association with the degree of leptomeningeal disease, venous dural sinus thrombosis, or modified Rankin Scale scores. In conclusion, deep medullary vein engorgement was common in our patients with neurosarcoidosis. Although its pathophysiology remains uncertain, it could be related to venous or perivenous abnormalities and may represent a useful secondary finding of cerebrovascular disease.

Integrative radiomics expression predicts molecular subtypes of primary clear cell renal cell carcinoma.

AIM: To identify combined positron-emission tomography (PET)/magnetic resonance imaging (MRI)-based radiomics as a surrogate biomarker of intratumour disease risk for molecular subtype ccA and ccB in patients with primary clear cell renal cell carcinoma (ccRCC). MATERIALS AND METHODS: PET/MRI data were analysed retrospectively from eight patients. One hundred and sixty-eight radiomics features for each tumour sampling based on the regionally sampled tumours with 23 specimens were extracted. Sparse partial least squares discriminant analysis (SPLS-DA) was applied to feature screening on high-throughput radiomics features and project the selected features to low-dimensional intrinsic latent components as radiomics signatures. In addition, multilevel omics datasets were leveraged to explore the complementing information and elevate the discriminative ability. RESULTS: The correct classification rate (CCR) for molecular subtype classification by SPLS-DA using only radiomics features was 86.96% with permutation test p=7×10-4. When multi-omics datasets including mRNA, microvascular density, and clinical parameters from each specimen were combined with radiomics features to refine the model of SPLS-DA, the best CCR was 95.65% with permutation test, p<10-4; however, even in the case of generating the classification based on transcription features, which is the reference standard, there is roughly 10% classification ambiguity. Thus, this classification level (86.96-95.65%) of the proposed method represents the discriminating level that is consistent with reality. CONCLUSION: Featured with high accuracy, an integrated multi-omics model of PET/MRI-based radiomics could be the first non-invasive investigation for disease risk stratification and guidance of treatment in patients with primary ccRCC.

Cavitary Plaques in Otospongiosis: CT Findings and Clinical Implications.

BACKGROUND AND PURPOSE: Cavitary plaques have been reported as a manifestation of otospongiosis. They have been related to third window manifestations, complications during cochlear implantation, and sensorineural hearing loss. However, their etiology and clinical implications are not entirely understood. Our purpose was to determine the prevalence, imaging findings, and clinical implications of cavitary plaques in otospongiosis. MATERIALS AND METHODS: We identified patients with otospongiosis at a tertiary care academic medical center from January 2012 to April 2017. Cross-sectional CT images and clinical records of 47 patients (89 temporal bones) were evaluated for the presence, location, and imaging features of cavitary and noncavitary otospongiotic plaques, as well as clinical symptoms and complications in those who underwent cochlear implantation. RESULTS: Noncavitary otospongiotic plaques were present in 86 (97%) temporal bones and cavitary plaques in 30 (35%). Cavitary plaques predominated with increasing age (mean age, 59 years; P = .058), mostly involving the anteroinferior wall of the internal auditory canal (P = .003), and their presence was not associated with a higher grade of otospongiosis by imaging (P = .664) or with a specific type of hearing loss (P = .365). No patients with cavitary plaques had third window manifestations, and those with a history of cochlear implantation (n = 6) did not have complications during the procedure. CONCLUSIONS: Cavitary plaques occurred in one-third of patients with otospongiosis. Typically, they occurred in the anteroinferior wall of the internal auditory canal. There was no correlation with the degree of otospongiosis, type of hearing loss, or surgical complications. Cavitary plaques tended to present in older patients.

Brain MR Imaging Findings of Cardiac-Type Fabry Disease with an IVS4+919G>A Mutation.

BACKGROUND AND PURPOSE: A high incidence of cardiac-type Fabry disease with an α-galactosidase A mutation, IVS4 + 919 G>A, has been identified in the Taiwanese population. The neurologic manifestation has not been understood in this specific cardiac variant. This study aimed to investigate the typical imaging features of classic Fabry disease in patients with IVS4 Fabry disease. MATERIALS AND METHODS: Twenty-six patients with IVS4-type Fabry disease (20 men and 6 women; age range, 43-71 years; median age, 61 years) and 26 age- and sex-matched healthy controls (age range, 44-68 years; median age, 60 years) were analyzed for white matter hyperintensities, the pulvinar sign, and basilar artery diameter. The volumes of white matter hyperintensities were calculated by comparison with an in-house data base of 276 controls. RESULTS: Infarctions were found in 9 patients with IVS4 Fabry disease (35%) and in none of the healthy controls (P = .001). A pulvinar sign was found in 8 patients with IVS4 Fabry disease (30%) and in none of the healthy controls (P = .002). No significant difference was found in Fazekas scale scores for white matter hyperintensities; however, white matter hyperintensity volume in the deep white matter was higher in patients with IVS4 Fabry disease than in those from the healthy control data base (P = .004). CONCLUSIONS: Along with its involvement of the cardiac system, IVS4-type Fabry disease has features similar to those of classic Fabry disease and a higher frequency of deep white matter hyperintensities and a higher incidence of infarctions and pulvinar signs than in healthy controls.

Changes of time-attenuation curve blood flow parameters in patients with and without carotid stenosis.

BACKGROUND AND PURPOSE: From the time-attenuation curves of DSA flow parameters, maximal intensity, maximal slope, and full width at half maximum of selected vascular points are defined. The study explores the reliability of defining the flow parameters by the time-attenuation curves of DSA. MATERIALS AND METHODS: Seventy patients with unilateral carotid artery stenosis (group A) and 56 healthy controls (group B) were retrospectively enrolled. Fixed contrast injection protocols and DSA acquisition parameters were used with all patients. The M1, sigmoid sinus, and internal jugular vein on anteroposterior view DSA and the M2, parietal vein, and superior sagittal sinus on lateral view DSA were chosen as ROI targets for measuring flow parameters. The difference of time of maximal intensity between 2 target points was defined as the circulation time between the target points. RESULTS: The maximal intensity difference of 2 selected points from the ICA to the M1, sigmoid sinus, internal jugular vein, M2, parietal vein, and superior sagittal sinus was significantly longer in group A than in group B. The maximum slope of M1, M2, and the superior sagittal sinus was significantly lower in group A than in group B. The full width at half maximum of M1 and M2 was significantly larger in group A than in group B. The maximal slope of M1 demonstrated the best diagnostic performance. CONCLUSIONS: The maximal intensity difference of 2 selected points derived from DSA can be used as a definitive alternative flow parameter for intracranial circulation time measurement. Maximal slope and full width at half maximum complement the maximal intensity difference of 2 selected points in defining flow characteristics of healthy subjects and patients with carotid stenosis.

Pretreatment diagnosis of suprasellar papillary craniopharyngioma and germ cell tumors of adult patients.

BACKGROUND AND PURPOSE: Suprasellar papillary craniopharyngiomas and germ cell tumors in adults share some clinical and imaging similarities but have different therapeutic strategies and outcomes. This study aimed to evaluate the pretreatment diagnosis of these 2 tumors to improve the therapeutic outcome. MATERIALS AND METHODS: We retrospectively enrolled 18 adults with papillary craniopharyngiomas and 17 with germ cell tumors. The MR imaging findings were evaluated, including signal change and anatomic extension. The medical records were reviewed to collect clinical findings, management, and outcomes. RESULTS: The clinical findings of papillary craniopharyngiomas versus germ cell tumors were as follows: age: 46 ± 13.9 years versus 23 ± 7.1 years (P < .0001); diabetes insipidus: 2/18 (11%) versus 11/17 (65%) (P = .001); recurrence 13/16 (81%) versus 4/17 (24%) (P = .0031). The MR imaging findings of papillary craniopharyngiomas versus germ cell tumors were as follows­pituitary stalk thickening: 1.6 ± 0.4 mm versus 5.4 ± 4.2 mm (P < .0001); vertical infundibular extension: 1/18 (6%) versus 16/17 (94%) (P < .0001); sagittal spheric shape: 17/18 (94%) versus 1/17 (6%) (P < .0001); diffusion restriction: 1/17 (6%) versus 8/12 (67%) (P = .0009). CONCLUSIONS: Younger age, diabetes insipidus, MR imaging characteristics of restricted diffusion, and vertical infundibular extension favor the diagnosis of germ cell tumors. Spheric shape without infundibular infiltration provides clues to papillary craniopharyngiomas, which originate from the pars tuberalis and are located outside the third ventricle. We suggest that suprasellar germ cell tumor is possibly an intraventricular lesion. Appropriate treatment planning can be initiated according to the diagnosis and anatomic location.

Artifact reduction of different metallic implants in flat detector C-arm CT.

BACKGROUND AND PURPOSE: Flat detector CT has been increasingly used as a follow-up examination after endovascular intervention. Metal artifact reduction has been successfully demonstrated in coil mass cases, but only in a small series. We attempted to objectively and subjectively evaluate the feasibility of metal artifact reduction with various metallic objects and coil lengths. MATERIALS AND METHODS: We retrospectively reprocessed the flat detector CT data of 28 patients (15 men, 13 women; mean age, 55.6 years) after they underwent endovascular treatment (20 coiling ± stent placement, 6 liquid embolizers) or shunt drainage (n = 2) between January 2009 and November 2011 by using a metal artifact reduction correction algorithm. We measured CT value ranges and noise by using region-of-interest methods, and 2 experienced neuroradiologists rated the degrees of improved imaging quality and artifact reduction by comparing uncorrected and corrected images. RESULTS: After we applied the metal artifact reduction algorithm, the CT value ranges and the noise were substantially reduced (1815.3 ± 793.7 versus 231.7 ± 95.9 and 319.9 ± 136.6 versus 45.9 ± 14.0; both P < .001) regardless of the types of metallic objects and various sizes of coil masses. The rater study achieved an overall improvement of imaging quality and artifact reduction (85.7% and 78.6% of cases by 2 raters, respectively), with the greatest improvement in the coiling group, moderate improvement in the liquid embolizers, and the smallest improvement in ventricular shunting (overall agreement, 0.857). CONCLUSIONS: The metal artifact reduction algorithm substantially reduced artifacts and improved the objective image quality in every studied case. It also allowed improved diagnostic confidence in most cases.

Stenotic transverse sinus predisposes to poststenting hyperperfusion syndrome as evidenced by quantitative analysis of peritherapeutic cerebral circulation time.

BACKGROUND AND PURPOSE: Hyperperfusion syndrome is a devastating complication of carotid stent placement. The shortening of cerebral circulation time after stent placement is seen as a good indicator of the development of hyperperfusion syndrome. The purpose of our study was to evaluate whether patients with ipsilateral transverse sinus stenosis are prone to having shortened cerebral circulation time after stent placement, subsequently leading to the possible development of hyperperfusion syndrome. MATERIALS AND METHODS: Forty-nine patients with >70% unilateral carotid stenosis undergoing stent placement were recruited for analysis. Group A consisted of patients with a stenotic ipsilateral transverse sinus >50% greater than the diameter of the contralateral transverse sinus; the remaining patients were in group B. Quantitative DSA was used to calculate cerebral circulation time. Cerebral circulation time was defined as the time difference between the relative time to maximal intensity of ROIs in the proximal internal carotid artery and the internal jugular vein. ΔCCT was defined as cerebral circulation time before stent placement minus cerebral circulation time after stent placement. ΔCCT, white matter hyperintensity signals, and sulcal effacement in MR imaging were compared between the 2 groups. RESULTS: ΔCCT was significantly shorter in group A (0.65 ± 1.3) than in group B (-0.12 ± 1.4). Three patients had white matter hyperintensity signals in group A, and 1 developed hyperperfusion syndrome. Group B showed no MR imaging signs of hyperperfusion syndrome. CONCLUSIONS: Ipsilateral hypoplastic transverse sinus was associated with prolonged cerebral circulation time before stent placement and greatly shortened cerebral circulation time after stent placement. Inadequate venous drainage might play a role in impaired cerebral autoregulation and might influence the development of poststenting hyperperfusion syndrome.

Radiation doses of cerebral blood volume measurements using C-arm CT: A phantom study.

BACKGROUND AND PURPOSE: Parenchymal blood volume measurement by C-arm CT facilitates in-room peritherapeutic perfusion evaluation. However, the radiation dose remains a major concern. This study aimed to compare the radiation dose of parenchymal blood volume measurement using C-arm CT with that of conventional CTP using multidetector CT. MATERIALS AND METHODS: A biplane DSA equipped with C-arm CT and a Rando-Alderson phantom were used. Slab parenchymal blood volume (8-cm scanning range in a craniocaudal direction) and whole-brain parenchymal blood volume with identical scanning parameters, except for scanning ranges, were undertaken on DSA. Eighty thermoluminescent dosimeters were embedded into 22 organ sites of the phantom. We followed the guidelines of the International Commission on Radiation Protection number 103 to calculate the effective doses. For comparison, 8-cm CTP with the same phantom and thermoluminescent dosimeter distribution was performed on a multidetector CT. Two repeat dose experiments with the same scanning parameters and phantom and thermoluminescent dosimeter settings were conducted. RESULTS: Brain-equivalent dose in slab parenchymal blood volume, whole-brain parenchymal blood volume, and CTP were 52.29 ± 35.31, 107.51 ± 31.20, and 163.55 ± 89.45 mSv, respectively. Variations in the measurement of an equivalent dose for the lens were highest in slab parenchymal blood volume (64.5%), followed by CTP (54.6%) and whole-brain parenchymal blood volume (29.0%). The effective doses of slab parenchymal blood volume, whole-brain parenchymal blood volume, and CTP were 0.87 ± 0.55, 3.91 ± 0.78, and 2.77 ± 1.59 mSv, respectively. CONCLUSIONS: The dose measurement conducted in the current study was reliable and reproducible. The effective dose of slab parenchymal blood volume is about one-third that of CTP. With the advantages of on-site and immediate imaging availability and saving procedural time and patient transportation, slab parenchymal blood volume measurement using C-arm CT can be recommended for clinical application.

Evaluation of the outcomes of endovascular management for patients with head and neck cancers and associated carotid blowout syndrome of the external carotid artery.

AIM: To evaluate factors related to the technical and haemostatic outcomes of endovascular management in patients with head and neck cancers (HNC) associated with carotid blowout syndrome (CBS) of the external carotid artery (ECA). MATERIALS AND METHODS: Between 2002 and 2011, 34 patients with HNC with CBS involving branches of the ECA underwent endovascular therapy. Treatment included embolization with microparticles, microcoils, or acrylic adhesives. Fisher's exact test was used to examine demographic features, clinical and angiographic severities, and clinical and imaging findings as predictors of endovascular management outcomes. RESULTS: Technical success and immediate haemostasis were achieved in all patients. Technical complications were encountered in one patient (2.9%). Rebleeding occurred in nine patients (26.5%). Angiographic vascular disruption grading from slight (1) to severe (4) revealed that the 18 patients with acute CBS had scores of 2 (2/18, 11.1%), 3 (3/18, 16.7%), and 4 (13/18, 72.2%). The 16 patients with impending and threatened CBS had scores of 1 (1/16, 6.25%), 2 (5/16, 31.25%), and 3 (10/16, 62.5%; p = 0.0003). For the 25 patients who underwent preprocedural computed tomography (CT)/magnetic resonance imaging (MRI) examinations within 3 months of treatment, the agreement between clinical and imaging findings reached the sensitivity, specificity, and kappa values for recurrent tumours (1, 0.7143, 0.7826), soft-tissue defect (0.9091, 0.3333, 0.2424), and sinus tract/fistula (0.4737, 0, 0.4286). CONCLUSION: Endovascular management for patients with CBS of the ECA had high technical success and safety but was associated with high rebleeding rates. We suggest applying aggressive post-procedural follow-up and using preprocedural CT/MRI to enhance the periprocedural diagnosis.

The use of hypoxic cultured mesenchymal stem cell for oncolytic virus therapy.

The safety of oncolytic viruses, such as conditionally replicative adenoviruses (CRAds), has been validated in clinical trials for cancer therapy. Their antitumor efficacy is limited by the presence of preexisting neutralizing antibodies (NAbs). Mesenchymal stem cells (MSCs) are attractive as a cellular vehicle to carry antitumor agents, not only because they are easily obtained and expanded to great numbers in vitro, but also because of their ability to migrate and engraft to tumors. MSCs expanded under hypoxic conditions decrease in replicative senescence and increase in proliferation capacity and differentiation potentials. However it remains to be clarified whether these hypoxic MSCs also are good carriers for the delivery of CRAds to tumor cells in the presence of NAbs. This study firstly demonstrated hypoxic MSCs with an increased ability to migrate toward tumors through the upregulation of chemokine receptors, such as CXCR4 and CX3CR1. It is then demonstrated that hypoxic MSCs has the capacity to carry CRAds, without inducing apoptosis, for up to one week. Using an in vitro coculture with human colon cancer cells and with intraperitoneally (i.p.) and subcutaneously (s.c.) developed human colon cancer xenografts, it is demonstrated that hypoxic MSCs are able to protect CRAds from attack by NAbs, thereby successfully delivering them to the target tumor cells. These results show that hypoxic MSCs can serve as cell carriers for CRAds and may help to develop new strategies against cancer.

Synergistic interaction of benign prostatic hyperplasia and prostatitis on prostate cancer risk.

BACKGROUND: The incidence of prostate cancer is much lower in Asian men than in Western men. This study investigated whether prostate cancer is associated with prostatitis, benign prostatic hyperplasia (BPH), and other medical conditions in the low-incidence population. METHODS: From the claims data obtained from the universal National Health Insurance of Taiwan, we identified 1184 patients with prostate cancer diagnosed from 1997 to 2008. Controls comprised 4736 men randomly selected from a cancer-free population. Both groups were 50 years of age or above. Medical histories between the two groups were compared. RESULTS: Multivariate logistic regression analysis showed that prostatitis and BPH had stronger association with prostate cancer than the other medical conditions tested. Compared with men without prostatitis and BPH, a higher odds ratio (OR) for prostate cancer was associated with BPH (26.2, 95% confidence interval (CI) 20.8-33.0) than with prostatitis (10.5, 95% CI=3.36-32.7). Men with both conditions had an OR of 49.2 (95% CI=34.7-69.9). CONCLUSION: Men with prostate cancer have strong association with prostatitis and/or BPH. Prostatitis interacts with BPH, resulting in higher estimated relative risk of prostate cancer in men suffering from both conditions.

Can iterative reconstruction improve imaging quality for lower radiation CT perfusion? Initial experience.

BACKGROUND AND PURPOSE: Initial results using IR for CT of the head showed satisfactory subjective and objective imaging quality with a 20-40% radiation dose reduction. The aim of our study was to compare the influence of IR and FBP algorithms on perfusion parameters at standard and lowered doses of CTP. MATERIALS AND METHODS: Forty patients with unilateral carotid stenosis post-carotid stent placement referred for follow-up CTP were divided into 2 groups (tube currents were 100 mAs in group A and 80 mAs in group B). Datasets were reconstructed with IR and FBP algorithms; and SNRs of gray matter, white matter, and arterial and venous ROIs were compared. CBF, CBV, and MTT means and SNRs were evaluated by using linear regression, and qualitative imaging scores were compared across the 2 algorithms. RESULTS: The mean effective radiation dose of group B (2.06 mSv) was approximately 20% lower than that of group A (2.56 mSv). SNRs for ROIs in the dynamic contrast-enhanced images were significantly higher than those for the FBP images. Correlations of the SNRs for CBF, CBV, and MTT across the 2 algorithms were moderate (R² = 0.46, 0.23, and 0.44, respectively). ROIs in gray matter rather than the IR algorithm predicted increasing SNRs in all CBF, CBV, and MTT maps. Two cases of significant restenosis were confirmed in both algorithms. CBV, CBF, and MTT imaging scores did not differ significantly across algorithms or groups. CONCLUSIONS: Lower dose CTP (20% below normal dose) without IR can effectively identify oligemic tissue in poststenting follow-up. IR does not alter the absolute values or increase the SNRs of perfusion parameters. Other methods should be attempted to improve SNRs in settings with low tube currents.

Mesenchymal stem cells promote growth and angiogenesis of tumors in mice.

Though the early integration of mesenchymal stem cells (MSCs) into tumor-associated stroma of cancer has been demonstrated, the functional contributions and underlying mechanisms of these cells to tumor growth and angiogenesis remain to be clarified. Using a xenograft model, human colorectal cancer cells, MSCs, and their cell mixture were introduced to a subcutaneous site of immunodeficient mice. The tumor growth rate and angiogenesis of each transplantation was then compared. We demonstrate that a variety of colorectal cancer cells, when mixed with otherwise non-tumorigenic MSCs, increase the tumor growth rate and angiogenesis more than that when mixed with carcinoma-associated fibroblasts or normal colonic fibroblasts. The secretion of interleukin-6 (IL-6) from MSCs increases the secretion of endothelin-1 (ET-1) in cancer cells, which induces the activation of Akt and ERK in endothelial cells, thereby enhancing their capacities for recruitment and angiogenesis to tumor. The IL-6/ET-1/Akt or ERK pathway of tumor-stroma interaction can be targeted by an antibody against IL-6 or Lentiviral-mediated RNAi against IL-6 in MSCs, by inhibition or knockdown of ET-1 in cancer cells, or by inhibition of ERK and Akt in host endothelial cells. These demonstrate that attempts to interrupt the interaction of MSCs and cancer cells help to abrogate angiogenesis and inhibit tumor growth in tumors formed by cancer cells admixed with MSCs. These data demonstrate that the tumor microenvironment, namely, MSCs-secreted IL-6, may enrich the proangiognic factors secreted by cancer cells to increase angiogenesis and tumor growth and that targeting this interaction may lead to novel therapeutic and preventive strategies.

In-room assessment of cerebral blood volume for guidance during intra-arterial thrombolytic therapy.

In acute ischemic stroke, the ability to estimate the penumbra and infarction core ratio helps to triage those who will potentially benefit from thrombolytic therapies. Flat-panel post-contrast DynaCT imaging can provide both vasculature and parenchymal blood volume within the angio room to monitor hemodynamic changes during the endovascular procedures. We report on an 80-year-old woman who suffered from an acute occlusion of the right distal cervical internal carotid artery. She was transferred to the angio room where in-room post-contrast flat-panel DynaCT imaging (syngo Neuro PBV IR) was performed to access the ischemic tissue, followed by successful mechanical thrombolytic therapy.

Monitoring peri-therapeutic cerebral circulation time: a feasibility study using color-coded quantitative DSA in patients with steno-occlusive arterial disease.

BACKGROUND AND PURPOSE: Intracranial hemodynamics are important for management of SOAD. This study aimed to monitor peri-stent placement intracranial CirT of patients with SOAD. MATERIALS AND METHODS: Twenty-five patients received stent placement for extracranial ICA stenosis, and 34 patients with normal CirT were recruited as controls. Their color-coded DSAs were used to define the Tmax of selected intravascular ROI. A total of 20 ROIs of the ICA, OphA, ACA, MCA, FV, PV, OV, SSS, SS, IJV, and MCV were selected. rTmax was defined as the Tmax at the selected region of interest minus Tmax at the cervical segment of the ICA (I1 on AP view and IA on lateral view). rTmax of the PV was defined as intracranial CirT. Intergroup and intragroup longitudinal comparisons of rTmax were performed. RESULTS: rTmax values of the normal cohorts were as follows: ICA-AP, 0.12; ICA-LAT, 0.10; A1, 0.28; A2, 0.53; A3, 0.81; M1, 0.40; M2, 0.80; M3, 0.95; OphA, 0.35; FV, 4.83; PV, 5.11; OV, 5.17; SSS, 6.16; SS, 6.51; IJV, 6.81; and MCV, 3.86 seconds. Before stent placement, the rTmax values of arterial ROIs, except A3 and M3, were prolonged compared with values from control subjects (P < .05). None of the rTmax of any venous ROIs in the stenotic group was prolonged with significance. After stent placement, the rTmax of all arterial ROIs shortened significantly, except A1and M3. Poststenting rTmax was not different from the control group. CONCLUSIONS: Without extra contrast medium and radiation dosages, color-coded quantitative DSA enables real-time monitoring of peri-therapeutic intracranial CirT in patients with SOAD .

Imaging characteristics of primary spinal primitive neuroectodermal tumors. A report of five cases and literature review.

Primary spinal primitive neuroectodermal tumors (PNETs) are rare and classified into peripheral and central types because the treatment strategy and outcome are different. This study describes five cases of primary spinal peripheral type PNETs. Magnetic resonance imaging showed large extradural masses in the cervical and thoracic spine with bony invasion and paraspinal extension in four cases and a transdural mass in the sacral spinal canal in one case. We also briefly summarize the imaging characteristics of 36 peripheral type and six central type primary spinal PNETs in the literature.