Normal Computed Tomography Angiography Research Articles

Morphometric CT angiographic study of the SSS and its adjacent structures: A comparative analysis between elderly and nonelderly individuals of a Han Chinese population

ObjectiveThe superior sagittal sinus (SSS) is an important structure, but few studies have analyzed it using computed tomography angiography (CTA). MethodsThis study was performed to examine the angiographic anatomy of the SSS and its adjacent structures using CTA in Han Chinese participants. According to age, participants were divided into elderly and nonelderly groups. The parameters of the SSS and adjacent structures were measured, recorded and analyzed statistically. ResultsA total of 500 Han Chinese participants were enrolled in this study, including 346 in the elderly group and 154 in the nonelderly group. In the elderly group, regarding inferior sagittal sinus (ISS) development, 187 ISSs were absent, 85 were visible, and 74 were clear. In the nonelderly group, 62 ISSs were absent, 54 were visible, and 38 were clear. In the elderly group, the Rolandic bridging vein diameter was 3.6 ± 0.8 mm; in the nonelderly group, the diameter was 3.9 ± 1.1 mm. The statistical results showed a difference in ISS development between the elderly and nonelderly groups (P < 0.05). The relationship of age with ISS development was assessed using linear regression analysis, and the results indicated that ISS became gradually occluded with age (P < 0.05). The statistical results also showed a difference in the Rolandic bridging vein diameter between the elderly and nonelderly groups (P < 0.05). The relationship of age with the Rolandic bridging vein diameter was assessed using linear regression analysis, and the results indicated that the Rolandic bridging vein tended to become thinner with age (P < 0.05). ConclusionThis study found that more ISSs may become occluded and that the Rolandic bridging vein may become thinner with age. Other parameters of the SSS and its adjacent structures may not be affected by aging. In addition, our study also provided normal CTA parameters of the SSS and its adjacent structures in Han Chinese people.

A Case-Control Study of Distinguishing Between Stroke Mimics and True Strokes.

This study was conducted with the primary aim to distinguish patients with a true stroke versus a stroke mimic based on clinical features and imaging. We conducted a retrospective case–control study on 116 adult patients who received alteplase (tPA) to treat acute stroke at our hospital. We further analyzed 79 patients with a normal computed tomography angiography (CTA). Based on their magnetic resonance imaging (MRI) of the brain, they were divided into cases (stroke mimics) and controls (true strokes).Data were collected retrospectively by reviewing individual medical charts on the electronic medical record (EMR), including age, gender, history of stroke, seizure, hypertension, diabetes, atrial fibrillation, hyperlipidemia, presenting NIH Stroke Scale/Score, hemorrhagic conversion, history of migraine, history of depression, sidedness of symptoms and aphasia. Data were categorized to separate those who were later diagnosed to be stroke mimics by being-postictal, encephalopathic, in acute migraine, suffered post-stroke recrudescence (PSR) due to metabolic insult, or had conversion disorder when symptoms could not be attributed to any medical condition or mental illness.Of the 79 study subjects, 48 (60%) were stroke mimics. The mean age of the cohort was 68.67 years, and 46.8% of the study subjects were females. Based on the multivariate logistic regression analysis, factors associated with being a stroke mimic were older age, history of migraine, and a history of prior stroke. In conclusion, increased attention to history and clinical examination as the first step can aid in the proper diagnosis of strokes versus stroke mimics.Identifying stroke mimics early could help expedite hospital workup and prevent inadvertent investigations, reducing hospital occupancy during the ongoing COVID-19 pandemic. We could potentially avoid the administration of tPA to such patients, reducing both the cost and adverse effects of it. Every stroke can cause neurological deficits, but every deficit need not be a stroke.

Artificial Intelligence Algorithm-Based CTA Imaging for Diagnosing Ischemic Type Biliary Lesions after Orthotopic Liver Transplantation.

The study focused on the clinical application value of artificial intelligence-based computed tomography angiography (CTA) in the diagnosis of orthotopic liver transplantation (OLT) after ischemic type biliary lesions (ITBL). A total of 66 patients receiving OLT in hospital were selected. Convolutional neural network (CNN) algorithm was used to denoise and detect the edges of CTA images of patients. At the same time, the quality of the processed image was subjectively evaluated and quantified by Hmax, Ur, Cr, and other indicators. Then, the digital subtraction angiography (DSA) diagnosis and CTA diagnosis based on CNN were compared for the sensitivity, specificity, positive predictive value, negative predictive value, and patient classification results. It was found that CTA can clearly reflect the information of hepatic aorta lesions and thrombosis in patients with ischemic single-duct injury after liver transplantation. After neural network algorithm processing, the image quality is obviously improved, the lesions are more prominent, and the details of lesion parts are also well displayed. ITBL occurred in 40 (71%) of 56 patients with abnormal CTA at early stage. ITBL occurred in only 8 (12.3%) of 65 patients with normal CTA at early stage. Early CTA manifestations had high sensitivity (72.22%), specificity (87.44%), positive predictive value (60.94%), and negative predictive value (92.06%) for the diagnosis of ITBL. It was concluded that artificial intelligence-based CTA had high clinical application value in the diagnosis of ITBL after OLT.

Diagnostic Value of Pulmonary Artery Hypodense and Hyperdense Luminal Sign in Non-Contrast Thoracic CT Scan for Detection of Pulmonary Embolism

This study evaluates the diagnostic value of hyperdense and hypodense foci in the lumen of pulmonary arteries and their branches for pulmonary embolism in thoracic CT Scan without contrast. In this study, imaging data of 171 patients who underwent both Non-contrast thoracic CT Scan and CT angiography were assessed. First, non-contrast thoracic CTs done by a multidetector CT machine were evaluated for abnormal intraluminal densities in pulmonary arteries and their branches. Then, the results were compared with the results of pulmonary CT angiography. In 58 patients (43/92%), the intraluminal signs (including hyperdense and hypodense) were seen in non-enhanced CT. According to the obtained results, 18 (31%) cases had normal CT Angiography, 24 patients (37/41%) had evidence of central emboli, and 16 patients (58/27%) had evidence of peripheral embolism. For the hyperdense luminal sign, false-negative rate, false-positive rate, sensitivity, specificity, PPV, and NPV for pulmonary embolism were 13/5%, 4/1%, 48/89%, 98/44%, 75/86%, and 83/80%, respectively. For the hypodense luminal sign, false-negative rate, false-positive rate, sensitivity, specificity, PPV, and NPV for pulmonary embolism were 15/8%, 6/4%, 40%, 91/27%, 62/07%, and 80/99% respectively. The results indicate that the hyperdense luminal sign has a high specificity and NPV for the diagnosis of PE, especially for central embolism. However, the sensitivity and PPV of this sign are not significant. Also, the hypodense luminal sign has a high specificity and PPV for the diagnosis of PE, but its sensitivity and PPV are not substantial.

The role of computed tomography angiogram in intracranial hemorrhage. Do the benefits justify the known risks in everyday practice?

BackgroundIntracranial hemorrhage is a commonly encountered medical problem frequently evaluated by computed tomography angiography (CTA). In CTA, there is radiation exposure and possible adverse effects of intravenous contrast administration. Therefore, the yield of this diagnostic tool needs to be explored in a heterogeneous group of daily encountered patients to provide insight into the risks and benefits of CTA. ObjectiveTo evaluate the role of cerebral CTA in patients with CT-confirmed or clinically suspected intracranial hemorrhage. MethodsThis retrospective study included all patients who underwent cerebral CTA for evaluation of intracranial hemorrhage that was diagnosed by a plain CT scan or suspected clinically from January 1, 2010, to May 30, 2018. All the scans were evaluated for abnormalities of the cerebral arteries in the CTA. ResultsOne hundred twenty patients were included, 74 % were males, and the mean age was 46 years. Approximately 18 % were trauma patients. Overall, CTA was abnormal in 52 % of cases, aneurysms were found in 27 %, and arteriovenous malformation (AVM) in 8 %. Among 82 patients who had a hemorrhage on the plain CT scans, 54 % had normal CTA, 28 % showed aneurysm, and 11 % showed AVM. In trauma patients, the most common CTA finding was normality (48 %), followed by aneurysms (19 %) and dissection (14 %). In non-trauma patients, the most common CTA finding was normality (49 %), followed by aneurysms (28 %) and AVM (10 %). ConclusionsCTA is a valuable diagnostic tool for intracranial hemorrhage because it detected abnormalities related to the hemorrhage in 42 % of patients. However, because more than half (58 %) of the patients had normal CTAs or showed CTA findings that were not relevant to the hemorrhage, clinical judgment should be exhausted before exposing them to radiation and intravenous contrast risks.

Assessment of Cerebral Collateral Flow With Single-Phase Computed Tomography Angiography-Based Multimodal Scales in Patients With Acute Ischemic Stroke.

Assessing collateral status is important in acute ischemic stroke (AIS). The purpose of this study was to establish an easy and rapid method for evaluating collateral flow. A total of 60 patients with AIS were enrolled. The patients were aged 18 to 85 years with endovascular therapy treatment within 10 hours after the appearance of stroke symptoms, prestroke modified Rankin Scale ≤1, Alberta Stroke Program Early CT Score ≥6, and the occlusion of large vessels in anterior circulation. We reformed imaging strategies by conducting a small-dose group-injection test before normal computed tomography angiography (CTA) scanning and selected the visual collateral score and the regional leptomeningeal score scales as the single-phase CTA collateral flow assessment scales with the replacement of the parasagittal anterior cerebral artery territory by anterior cerebral artery regions adjacent to the longitudinal fissure and then verified, respectively, the consistencies between the 2 single-phase CTA-based collateral scales and the digital subtraction angiography (DSA)-based American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology scale and compared the prognosis of endovascular therapy between the AIS patients in the poor-collateral-flow group and the other patients' group assessed by 2 single-phase CTA-based collateral scales. There was a high consistency between the 2 single-phase CTA-based collateral flow scales with DSA-based American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology scale. The assessment by using CTA-based collateral flow assessment methods generated consistent results. The single-phase CTA-based visual collateral score scale and regional leptomeningeal score scale can be used as the imaging evidence for the evaluation of collateral flow in AIS patients in the majority of grassroots hospitals where DSA is difficult to carry out.

Atrial myxoma with cerebellar signs: a case report

BackgroundAtrial myxoma remains a rare clinical entity with an incidence of surgically resected cases of 0.5–0.7 per million population and prevalence of < 5 per 10,000. It typically manifests in woman after third decade of life; symptoms vary greatly and may present with arrhythmia, intracardiac flow obstruction, embolic phenomenon, and associated constitutional symptoms. Neurological complications associated with atrial myxoma most frequently include cerebral infarct due to embolus. Cerebellar involvement is very rare and only a few cases have been reported in the literature.Case presentationA 55-year-old Brahmin man with no history of diabetes mellitus and hypertension, presented with complaints of dizziness, headache, vomiting, double vision, and unsteadiness of gait for 2 weeks. His headache was sudden in onset, of a pulsating type and localized on left temporal side. Vomiting was projectile and bilious. Double vision was present in all directions of gaze and he had uncoordinated movement of his body and tilting to the left side. On examination, his cerebellar functions were impaired. He was thoroughly investigated for the cause of stroke after abnormal magnetic resonance imaging results with normal computed tomography angiography of his brain. Echocardiography and computed tomography of his chest showed a mass attached to intra-atrial septum and prolapsing through mitral valve, which was suggestive of left atrial myxoma. Five days following admission, he developed abdominal pain due to thromboembolism causing splenic and renal infarct.ConclusionAlthough rare, atrial myxoma has to be considered a cause of stroke and other embolic phenomenon causing multiorgan infarctions. Early and timely diagnosis of the condition can prevent further recurrence and inappropriate anticoagulant therapy. It would be pertinent to have echocardiography done in patients who present with a stroke, arrhythmias, and other constitutional symptoms. The tumor once detected must be removed surgically as early as possible, which not only reduces serious thromboembolic complications but can be potentially curative.

A Unique Signature of Cardiac-Induced Cranial Forces During Acute Large Vessel Stroke and Development of a Predictive Model.

Cranial accelerometry is used to detect cerebral vasospasm and concussion. We explored this technique in a cohort of code stroke patients to see whether a signature could be identified to aid in the diagnosis of large vessel occlusion (LVO) stroke. A military-grade three-axis accelerometer was affixed to a headset. Accelerometer and electrocardiogram (ECG) outputs were digitized at 1.6kHz. We call the resulting digitized signals the "headpulse." Three-minute recordings were performed immediately after computed tomography (CT) angiography (CTA) and/or immediately before and after attempted mechanical thrombectomy in patents with suspected stroke. The resulting waveforms were inspected by eye and then subjected to supervised machine learning (MATLAB Classification Learner R2018a) to train a model using fivefold cross-validation. Of 42 code stroke subjects with recordings, 19 (45%) had LVO and 23 (55%) had normal CTAs. In patients without LVO, ECG-triggered waveforms followed a self-similar time course revealing that the headpulse is highly coupled to the cardiac contraction. However, in most patients with LVO, headpulses showed little cardiac contraction correlation. We term this abnormality "chaos" and parameterized it with 156 measures of trace-by-trace variation from the ECG-signal-averaged mean for machine learning model training. Selecting the best model, using biometric data only, we properly classified 15/19 LVOs and 20/23 non-LVO patients, with receiver operating characteristic curve area = 0.79, sensitivity of 73%, and specificity of 87%, P < 0.0001. Headpulse waveforms following thrombectomy showed return of cardiac contraction correlation. Headpulse recordings performed on patients with suspected acute stroke significantly identify those with LVO. The lack of temporal correlation of the headpulse with cardiac contraction and resolution to normal may reflect changes in cerebral blood flow and may provide a useful technique to triage stroke patients for thrombectomy using a noninvasive device.

P6158Prognostic value of non-obstructive coronary artery disease detected on coronary computed tomography angiography among subjects with suspected coronary artery disease

Abstract Introduction Coronary Computed Tomography Angiography (CTA) is an established technique for the detection of coronary artery disease (CAD). However, the prognostic value of non-obstructive CAD is not well defined. Thus, the aim of this analysis is to determine the prognostic value of non-obstructive CAD detected on CTA. Methods In the Multi-Center Multi-Ethnic Coronary Computed Tomography Angiography (MECCA) Study, 3209 subjects without known CAD underwent CTA. Patients with obstructive CAD were excluded from this analysis. Patients with ≤70% luminal coronary artery stenosis in vessels other than the left main were classified to have non-obstructive CAD while patients without any plaque were considered to have normal CTA. Patients were followed up for a median duration of 3.4 years for all-cause mortality (ACM). Multivariable Cox models were used to determine the independent predictors of event-free survival. Results A total of 1455 subjects had non-obstructive CAD and 1382 subjects had normal coronary arteries. Subjects with non-obstructive CAD were older (55.9±11 vs 46.2±11 years, p&lt;0.001) and more likely to be males (56.8% vs 50.5%, p=0.001) and had more prevalent traditional risk factors. A total of 83 ACM were observed (4.4% in the non-obstructive group and 1.3% in the normal group, p&lt;0.001). Patients with clinical events were older (61.8±14 vs 50.9±12 years, p&lt;0.001) and have more prevalence of DM (42.2% vs 31.4%, p=0.031) and HTN (72.3% vs 54.3%, p=0.001). In Multivariable Cox models, non-obstructive CAD was associated with increased event rate (Hazard ratio 1.75, 95% CI 1.01–3.01, p=0.45). Kaplan-Meier Survival Curves Conclusions Patients with non-obstructive CAD on CTA have a higher rate of all-cause mortality. Non-obstructive CAD on CTA enhances risk stratification among subjects suspected with CAD and should call for more aggressive guidelines directed medical therapy. Acknowledgement/Funding None

Can vessel diameters, diameter ratios, and vessel angles predict the development of anterior communicating artery aneurysms: A morphological analysis

The anterior communicating artery (AcomA) junction is the most common location for cerebral aneurysms. This might because of increased vascular wall stress due to the complex structure of the junction. The aim of this study investigate the effect of morphological parameters in the development of AcomA aneurysms.This retrospective study was approved by the institutional ethics committee. A retrospective analysis of our hospital database was performed to identify patients with AcomA aneurysms. Patients with normal computed tomography angiography (CTA) examinations were enrolled in the study as the control group. The control group was similar to the patient group in gender and age. Morphological parameters (vessel diameters, vessel diameter ratios, and vessel angles) on the same side (ipsilateral) and on the opposite side (contralateral) of the patients with aneurysm, and morphological parameters of the control group were compared. A total of 171 subjects were involved in the study (86 patients with aneurysms and 85 patients in the control group). Multivariate regression analysis revealed that the ipsilateral A1–A2 angle (OR: 0.932; 95% CI: 0.903–0.961; p < 0.001), the ipsilateral A1/A2 vessel diameter ratio (OR: 27.725; 95% CI: 1.715–448.139; p = 0.019), and the contralateral internal carotid artery (ICA)/A1 ratio (OR: 11.817; 95% CI: 2.617–53.355; p = 0.001) were significant morphological predictors for developing an aneurysm.An increased contralateral ICA/A1 ratio, an increased ipsilateral A1/A2 vessel diameter ratio, and a narrow bifurcation angle are significant predictors for developing an aneurysm. Therefore, in patients with clinical risk factors these parameters may be interpreted as additional morphological risk factors for developing an aneurysm.

Revised CT angiography venous score with consideration of infratentorial circulation value for diagnosing brain death.

BackgroundComputed tomography angiography (CTA) is largely performed in European countries as an ancillary test for diagnosing brain death. However, CTA suffers from a lack of sensitivity, especially in patients who have previously undergone decompressive craniectomy. The aim of this study was to assess the performance of a revised four-point venous CTA score, including non-opacification of the infratentorial venous circulation, for diagnosing brain death.MethodsA preliminary study of 43 control patients with normal CTAs confirmed that the infratentorial superior petrosal vein (SPV) was consistently visible. Therefore, 76 patients (including ten with decompressive craniectomy) who were investigated with 83 CTAs to confirm clinical brain death were consecutively enrolled between July 2011 and July 2013 at a university centre. The image analysis consisted of recording non-opacification of the cortical segment of the middle cerebral artery and internal cerebral vein (ICV), which were used as the reference CTA score, as well as non-opacification of the SPV. The diagnostic performance of the revised four-point venous CTA score based on the non-opacification of both the ICV and SPV was assessed and compared with that of the reference CTA score.ResultsThe revised four-point venous CTA score showed a sensitivity of 95 % for confirming clinical brain death versus a sensitivity of 88 % with the reference CTA score. Non-opacification of the SPV was observed in 95 % of the patients. In the decompressive craniectomy group, the revised four-point CTA score showed a sensitivity of 100 % compared with a sensitivity of 80 % using the reference CTA score.ConclusionCompared with the reference CTA score, the revised four-point venous CTA score based on ICV and SPV non-opacification showed superior diagnostic performance for confirming brain death, including for patients with decompressive craniectomy.

Preoperative Computed Tomography Angiography for Evaluation of Feasibility of Free Flaps in Difficult Reconstruction of Head and Neck.

Free tissue transfer has been advocated for anatomic and functional reconstruction of soft tissue defects after surgical removal of an extensive recurrent tumor and/or arising from previous irradiation in the head and neck. We report a case series of difficult reconstruction in the head and neck in which preoperative computed tomography (CT) angiography was utilized to evaluate the feasibility of free flap reconstruction. The preoperative radiological evaluation was performed to determine the availability of reliable vessels for anastomosis in free flap reconstruction. If none was found, regional pedicle flap or palliative treatment was applied instead. The use of CT angiography allows the clinical surgeon to perform precise surgical planning with greater confidence. This may improve surgical results, thereby potentially reducing perioperative morbidity. Twenty CT angiograms were obtained from 20 patients. All patients were men with a mean age of 57.2 years (range, 42-72 years) and were scheduled to undergo difficult reconstruction in the head and neck. All patients (20/20 [100%]) suffered from oral squamous cell carcinoma. They had all received extensive operations and radiation therapy. Eighteen patients (18/20 [90%]) had completed a course of perioperative irradiation. The CT angiography reports were used to perform detailed preoperative surgical planning accordingly. The findings of CT angiography were classified into 3 groups: group I: normal CT angiography (patent recipient arteries) (Fig. 3); group II: abnormal CT angiography (recipient vessels were present but stenosis or atherosclerotic lesions were noted) (Fig. 4); group III: abnormal CT angiography with no patent recipient arteries in bilateral sides of the neck (Fig. 5); CT angiography results were correlated to the operative findings. The patients were classified into 3 groups based on the angiographic findings. Six patients (6/20 [30%]) were assigned to group I, 8 patients (8/20 [40%]) to group II, and 6 patients (6/20 [30%]) to group III. In groups I and III, all patients (12/12 [100%]) underwent the treatment according to the original preoperative detailed planning. No flap failure was noted in these 2 groups. In group II, 4 patients' recipient vessels (4/8 [50%]) possessed adequate blood flow intraoperatively; hence, microvascular free flaps were transplanted. Venous congestion in 1 case (1/4 [25%]) was noted. The remaining patients in this group (4/8 [50%]) underwent reconstruction with pedicle flaps rather than free flaps because of the lack of suitable target vessels intraoperatively. All flaps (4/4 [100%]) survived. Among the patients who were treated surgically, intraoperative findings were in accordance with those predicted by CT angiography. The total abnormality rate of CT angiography was 70%. Vascular abnormalities detected as a result of preoperative CT angiography led to changes in the operative plan in 50% (10/20) of the patients. The use of CT angiography should be considered for difficult microsurgical reconstructions in the head and neck. When an abnormality in vascular anatomy is detected by CT angiography, the surgeon is advised to consider altering the operative plan accordingly. This allows precise operation, thereby maximizing the possibility of an optimal outcome. Changing the operative plan based on results of CT angiography may also help to avoid the difficult situation in which the surgeon finds that there are no suitable recipient vessels for free flap reconstruction during the operation. In addition, CT angiography enables surgeons to conduct the preoperative surgical planning with greater confidence, thereby potentially enhancing the success rate of difficult reconstructions in the head and neck, which in turn would tend to improve the perioperative course for the patient and consequently to improve results by decreasing vascular complication rates.

Tuberculomas Mimicking Posterior-Circulation Stroke

Dear Editor, Posterior-circulation stroke is of grave concern to any physician versed with the mortality and morbidity associated with the condition. Various nonvascular neurological and nonneurological conditions may mimic posterior-circulation stroke. We report a 29-year-old male with no prior comorbidities who presented to the emergency room of a tertiary-care hospital in northern India with sudden-onset alteration in consciousness following severe vertigo with multiple episodes of vomiting and gait imbalance. Detailed history-taking revealed the presence of pain in the nape of the neck and low-grade fever for the previous 10 days and a history of chiropractic neck manipulation for the previous 7 days. The possibility of acute posterior-circulation stroke following vertebral artery dissection was considered, and a computed tomography (CT) scan of the head was performed on an emergency basis. The CT scan revealed a large hypodensity in the midbrain, pons, and cerebellum (Fig. 1A). However, CT angiography of the neck and the intracranial vessels did not show any evidence of vertebral artery dissection. Routine hemogram, biochemistry, and chest X-ray findings were normal. The possibility of an alternative diagnosis was considered, based specifically on the history of preceding fever and the normal CT angiography findings. Magnetic resonance imaging (MRI) of the brain revealed multiple ring enhanced lesions in the cerebellum with significant surrounding perilesional edema (Fig. 1B and C). Cerebral spinal fluid (CSF) analysis showed a total count of 250 cells/mm3, predominantly lymphocytes, with proteins 90 at mg/dL and sugar at 35 mg/dL. Cryptococcal antigen, acid fast bacilli stain, and fungal smear findings were negative in the CSF. The blood sugar level was 121 mg/dL. The possibility of multiple infratentorial tuberculomas was considered, and the patient was started on antitubercular therapy with steroids. The patient was completely asymptomatic after 6 months of treatment. Fig. 1 A: Contrast enhanced CT head showing hypodensity of pons and cerebellum. B and C: Shows multiple ring enhancing lesions in cerebellum on contrast enhanced, T1 weighted MRI brain. Posterior-circulation stroke is associated with grave mortality and morbidity statistics.1 A population-based case-control study2 found that chiropractic manipulation was positively correlated with vertebrobasilar accidents, specifically in subjects aged <45 years. There are abundant data in the Western literature that have increased public concern about the safety of chiropractic manipulation, but the situation is different in developing countries. Various nonvascular neurological and nonneurological conditions may mimic posterior-circulation stroke, including acute peripheral vestibular dysfunction, acute intracranial hemorrhage, subarachnoid hemorrhage, basilar migraine, hypoglycemia, central pontine myelinosis, postinfectious disorders, tumors, and many toxic and metabolic disturbances.3 Although chronic infectious and inflammatory disorders may also simulate this condition, a hyperacute presentation should always be addressed immediately. Tuberculosis is a imitator. In 1961, Sievers4 termed tuberculosis as the second great imitator after syphilis, based on his observations in the Indian population of southwestern United States suffering from tuberculosis. Tuberculomas of the brain account for 20–30% of lesions occupying the intracranial space in India, and multiple such lesions are present in 15–30% cases.5 Tuberculomas can affect any part of brain, but those with an infratentorial origin are rare. There are isolated cases of brainstem or cerebellar tuberculomas reported in the literature. Though uncommon, infratentorial tuberculomas can be life-threatening.6 Gadolinium-enhanced MRI of the brain is a more sensitive modality for detecting tuberculomas. A retrospective analysis after performing brain MRI in the present patient produced consistent findings. While CT can be performed in most centers, it is not the diagnostic modality of choice, specifically when considering infratentorial lesions. Though clinically hyperacute presentations always warrant consideration of a vascular event, it must be remembered that tuberculosis is a great mimic, and can present with hyperacute presentations as described in the present case.

The negative predictive value of CT angiography in the setting of perimesencephalic subarachnoid hemorrhage

BackgroundPerimesencephalic subarachnoid hemorrhage (PMSAH) is only rarely associated with a ruptured cerebral aneurysm and CT angiography (CTA) has very good sensitivity and specificity for aneurysm detection. The necessity for invasive...

Is higher body temperature beneficial in ischemic stroke patients with normal admission CT angiography of the cerebral arteries?

BackgroundLow body temperature is considered beneficial in ischemic stroke due to neuroprotective mechanisms, yet some studies suggest that higher temperatures may improve clot lysis and outcomes in stroke patients treated with tissue plasminogen activator (tPA). The effect of increased body temperature in stroke patients treated with tPA and with normal computed tomography angiography (CTA) on admission is unknown. We hypothesized a beneficial effect of higher body temperature in the absence of visible clots on CTA, possibly due to enhanced lysis of small, peripheral clots.MethodsPatients with ischemic stroke admitted to our Stroke Unit between February 2006 and April 2013 were prospectively registered in a database (Bergen NORSTROKE Registry). Ischemic stroke patients treated with tPA with normal CTA of the cerebral arteries were included. Outcomes were assessed by the modified Rankin Scale (mRS) after 1 week. An excellent outcome was defined as mRS=0, and a favorable outcome as mRS=0–1.ResultsA total of 172 patients were included, of which 48 (27.9%) had an admission body temperature ≥37.0°C, and 124 (72.1%) had a body temperature <37.0°C. Body temperature ≥37.0°C was independently associated with excellent outcomes (odds ratio [OR]: 2.8; 95% confidence interval [CI]: 1.24–6.46; P=0.014) and favorable outcomes (OR: 2.8; 95% CI: 1.13–4.98; P=0.015) when adjusted for confounders.ConclusionWe found an association between higher admission body temperature and improved outcome in tPA-treated stroke patients with normal admission CTA of the cerebral arteries. This may suggest a beneficial effect of higher body temperature on clot lysis in the absence of visible clots on CTA.

Likelihood of aneurysmal subarachnoid haemorrhage in patients with normal unenhanced CT, CSF xanthochromia on spectrophotometry and negative CT angiography

Patients with suspected subarachnoid haemorrhage, a normal noncontrast computed tomography (CT) and cerebrospinal fluid (CSF) evidence of haemoglobin breakdown products often undergo CT angiography (CTA). If this is normal, then invasive catheter angiography may be offered. In current clinical practice, haemoglobin breakdown products are detected by spectrophotometry rather than visible xanthochromia, and CTA is performed on multidetector scanners. The aim of this study was to determine if such patients should still have a catheter angiography, given the associated risks. Patients positive for CSF spectrophotometry (n=26) were retrospectively identified from the clinical biochemistry information system and imaging data from the electronic radiology records were reviewed. Discharge letters were consulted to relate the biochemistry and radiology results to the final diagnosis. 15 patients with CT angiography were found. Nine patients had normal CT angiography. No causative aneurysms had been missed. One patient had small, coincidental aneurysms missed on initial reading of the CTA. The likelihood of a clinically significant aneurysm in a patient who is CT negative, lumbar puncture positive and CTA negative is low. Double reporting of negative CT angiograms may be advisable.

Dilated cardiomyopathy in patients with mutations in anoctamin 5

BackgroundHomozygous mutations in ANO5, a gene encoding anoctamin 5, a putative calcium-activated chloride channel, have recently been reported in patients with adult-onset myopathies or isolated high-CK levels. Cardiomyopathy has not previously been reported in these populations despite a proven expression of anoctamin 5 in the cardiac muscle. MethodsPatients presenting for the management of high-CK levels or overt myopathy with proven ANO5 mutations were prospectively investigated between June 2010 and March 2012 in Pitié Salpêtrière Hospital, according to a standardised protocol. Neurological and cardiological clinical examinations, CK assessment, electrocardiogram (ECG), and echocardiography were performed, as well as cardiac MRI and coronary CT angiography in patients with left ventricular (LV) dysfunction. ResultsOur study included 19 consecutive patients (male=15, age=46.2±12.7years) from 16 families. Five had asymptomatic high-CK levels and 14 had overt myopathy. One patient had a personal history of stable coronary artery disease with normal ventricular function. ECG showed ventricular premature beats in one patient. Echocardiography displayed LV dilatation in two patients, LV dysfunction in one, and both abnormalities in two who fulfilled criteria for dilated cardiomyopathy which was confirmed by cardiac MRI and normal CT angiography. ConclusionsDilated cardiomyopathy is a potential complication in patients with myopathies due to mutations in the ANO5 gene whose screening requires specific procedures.

Multi-detector CT angiographic imaging in the follow-up of patients after endovascular abdominal aortic aneurysm repair (EVAR)

BackgroundMultidetector computed tomography (MDCT) angiography represents the standard of reference in the follow-up of patients after endovascular abdominal aortic aneurysm repair (EVAR), being effective in the detection of the full spectrum of possible complications on both axial and 3D images.MethodsThe purpose of this article is to review the normal CT angiography findings of the different types of stent-grafts and to describe the radiological findings of early and late complications after EVAR on axial and reconstructed images. A selection of cases of post-EVAR MDCT angiography is presented to learn the techniques most commonly used for endovascular treatment, the correct CT scanning technique to acquire the data, the full gamut of possible procedure-related complications and how these complications usually appear on CT images.ConclusionMDCT angiography is an effective and specific technique in both the pre- and postoperative settings of EVAR procedures. A better understanding of the procedure, the devices, the normal postoperative imaging features and the possible procedure-related complications ensures optimal planning and follow-up of patients undergoing an EVAR procedure.

Abstract 2539: Evaluation of Emergency Department Acute Ischemic Stroke Patients With and Without Blockage on Computed Tomography Angiography

Background: CT angiography (CTA) provides early assessment of cerebral vasculature in ED patients presenting with Acute Ischemic Stroke (AIS). Prior studies using 4 row detector CT scanners have suggested that results may be used to determine who receives thrombolytics (tPA). We sought to evaluate the rate of normal CTA and the use of tPA in AIS patients with and without blockages using modern CT technology. Methods: We conducted a retrospective cohort study of all code stroke patients presenting to our ED over a 3 year period ending in February 2011. Inclusion criteria included an ED and neurology diagnosis of AIS with a CTA performed at presentation. All patients had a NIHSS score recorded at presentation and underwent imaging using a 64 row detector scanner (Phillips) with 50cc of non-ionic contrast. Demographic, imaging, and clinical data were collected. Modified Rankin Scores (mRS) were assigned at presentation and hospital discharge. Good clinical outcome was defined as a mRS of 0-2. Data are reported as frequencies and medians with interquartile ranges (IQR) as appropriate. Rates of tPA use were evaluated using χ 2 testing. Changes in mRS were evaluated with the paired t-test. Results: A total of 209 subjects met inclusion for analysis of which 104 (50%) were male and 116 (55%) had no blockage on CTA. The median NIHSS score and mortality rates were 14 (IQR 8-19), 14 (15%) with CTA blockage, and 4 (IQR 2-7), 3 (3%) for those without. The use of tPA occurred in 46(50%) with 29 patients receiving intra-arterial therapy, and 14 (12%) patients with and without blockage respectively. Post tPA bleeding occurred in 12 (13%) patients with blockage on CTA and in 0 patients without blockage. Use of tPA was significantly more frequent in patients with a blockage on CTA, P &lt;0.001. As a group, patients without a blockage had a significant decrease in mRS at discharge, however the overall difference was greater in the tPA group, difference = 0.4 (0.2-0.7) P&lt;0.0002 and 1.9 (1.2-2.6) P&lt;0.0001 respectively. Only AIS patients with a blockage and given tPA had a significant reduction of mRS, difference = 0.6 (0.2-1.0) P&lt;0.005 compared with no tPA, difference = -0.1 (-0.4-0.3) P&lt;0.7. Conclusion: More than half of our AIS patients presenting through our ED have no blockage on CTA. Patients with AIS and no blockage on CTA have less severe strokes and are less likely to receive tPA. Both AIS patients with and without a blockage on CTA appear to derive benefit from tPA.

3-Dimensional reconstruction of the venous system in patients suffering from pulsatile tinnitus

Conclusions: An abrupt change in the venous caliber, producing turbulent flow, may be a cause of pulsatile tinnitus (PT). The largest area/smallest area (L/S) ratio >4.75 may be a criterion indicating abrupt caliber change and causing PT. Objectives: Contrast-enhanced CT is recommended as an initial work-up modality in PT. But, in the majority of cases, no definite pathology can be found, even after extensive work-up. In these cases, the unilateral dominant venous system may be the cause of PT. The aim of this study was to compare, through 3D-reformatted images of the intracranial venous system, the volume, cross-sectional area, and caliber changes in patients with PT and normal controls. Methods: This was a cross-sectional study set in a tertiary referral center. Eleven patients (11 unilateral PT ears) and 12 normal control ears were enrolled. All the subjects were confirmed with normal CT angiography findings. The intracranial venous structure was three-dimensionally reconstructed. Three areas with the largest and the smallest dimension were selected for further analysis: the transverse sinus (T), isthmus (I), and the jugular bulb (B). The total volume, cross-sectional area, and cross-sectional area ratios of the three areas were compared in the PT group and the normal control group. Results: The L/S ratio was significantly increased in the PT group (5.01), compared with the control group (3.42). When the threshold value of the L/S ratio was assessed by the ROC method, 4.75 seemed to be the significant dissecting point. The sensitivity of this method was 0.64 and the specificity was 0.83.