Bridging thrombolysis improves survival rates at 90 days compared with direct mechanical thrombectomy alone in acute ischemic stroke due to basilar artery occlusion: a systematic review and meta-analysis of 1096 patients

BACKGROUND

Mechanical thrombectomy (MT) is an effective treatment for patients with acute ischemic stroke (AIS) from basilar artery occlusion (BAO).

OBJECTIVE

To compare the clinical outcomes of MT, with and without bridging intravenous thrombolysis (IVT), in acute BAO through a systematic review and meta-analysis of the current literature.

METHODS

Systematic searches of Medline, EMBASE, and Cochrane Central were undertaken on August 1, 2022. Good functional outcome defined as 90-day modified Rankin Scale score 0-2 was the primary outcome measure. Secondary outcome measures were 90-day mortality, successful post-thrombectomy recanalization (modified Thrombolysis in Cerebral Infarction score ≥2b), symptomatic intracranial hemorrhage (sICH), and subarachnoid hemorrhage (SAH).

RESULTS

Three studies reporting 1096 patients with BAO AIS were included in the meta-analysis. No significant differences in good functional outcome were detected between the two groups (RR=1.28 (95% CI 0.86 to 1.92); p=0.117). However, specifically patients with large artery atherosclerosis (LAA) benefited from bridging IVT (OR=2.52 (95% CI 1.51 to 4.22); p<0.001) with better functional outcomes. There was a significantly lower 90-day mortality rate for patients who underwent bridging IVT compared with MT alone (RR=0.70 (95% CI 0.62 to 0.80); p=0.008). No significant differences were detected in rates of post-treatment recanalization (RR=1.01 (95% CI 0.35 to 2.91); p=0.954), sICH (RR=0.96 (95% CI 0.66 to 1.42); p=0.724), and SAH (RR=0.93 (95% CI 0.31 to 2.83); p=0.563).

CONCLUSIONS

In patients with AIS due to BAO, bridging IVT was associated with lower mortality rates at 90 days, compared with direct MT. There were no improved functional outcomes or increased sICH or SAH between both arms, However, patients with LAA benefited from bridging IVT, with better functional outcomes.

Safety and clinical outcomes in endovascular treatment for symptomatic cerebral venous thrombosis: a single-center experience with meta-analysis

The role of mechanical thrombectomy (MT) in cerebral venous sinus thrombosis (CVT) is ambiguous. This study aims to share our experience with MT in CVT, supplemented by a meta-analysis on this treatment. All patients who had MT for CVT at our institution, between 2016 and 2021, were retrospectively reviewed for treatment indications, the technique used, success and complication rates, and clinical outcomes. A meta-analysis was performed for clinical and safety outcomes from published literature with > 10 patients. A total of 15 patients were included in this study. All had a venous hemorrhage or deteriorating despite anticoagulation. MT was performed using aspiration (with wide bore catheters) in 7 patients: aspiration with stent retriever in 5 and transjugular Fogarty-balloon thrombectomy in 3 patients. Adjunctive intra-sinus thrombolysis (IST) was used in 4 cases and venoplasty in 3. Technical success (restoring antegrade venous flow on arterial injection) was 100% with no procedure-related major complication. The direct transjugular approach was cheaper and faster. At 3-month follow-up, 86% of patients had good outcomes (MRS < 2). Meta-analysis of clinical and safety outcomes from 22 and 20 studies, respectively, demonstrated a positive association between MT and good outcomes as well as no significant association with hazardous periprocedural events. EVT via mechanical means for CVT is feasible in our series and meta-analysis. From our experience, trans-jugular Fogarty balloon embolectomy seems to be a potential cost-saving option, at least in a certain part of the world.

World federation of interventional and therapeutic neuroradiology (WFITN) federation assembly neurointerventional surgery safety checklist

Over the last 10 years, there has been a rise in neurointerventional case complexity, device variety and physician distractions. Even among experienced physicians, this trend challenges our memory and concentration, making it more difficult to remember safety principles and their implications. Checklists are regarded by some as a redundant exercise that wastes time, or as an attack on physician autonomy. However, given the increasing case and disease complexity along with the number of distractions, it is even more important now to have a compelling reminder of safety principles that preserve habits that are susceptible to being overlooked because they seem mundane. Most hospitals have mandated a pre-procedure neurointerventional time-out checklist, but often it ends up being done in a cursory fashion for the primary purpose of 'checking off boxes'. There may be value in iterating the checklist to further emphasize safety and communication. The Federation Assembly of the World Federation of Interventional and Therapeutic Neuroradiology (WFITN) decided to construct a checklist for neurointerventional cases based on a review of the literature and insights from an expert panel.

Delayed Presentation of Air Embolism Within Cerebral Arteries Following Computed Tomography-Guided Lung Biopsy

Computed tomography (CT)-guided percutaneous core needle biopsy of the lung is a frequently performed interventional radiological procedure. Most complications are minor and self-resolving. However, a rare but potentially fatal complication is that of systemic air embolism, especially when to the cerebral or coronary arteries. This study reports a case of delayed (12 hours after initial biopsy) air embolism in the cerebral arteries that resulted from an otherwise uncomplicated biopsy of a lung nodule. It is vital for early diagnostic confirmation and appropriate treatment if possible, though maximal efforts at prevention are still recommended.

A Novel Endovascular Treatment for Recurrent Secondary Aorto-Enteric Fistula in a Patient With Prior Infra-Renal Aortic Ligation

This report highlights the use of novel endovascular techniques in a 68-year-old male patient with massive hematemesis from a recurrent secondary aorto-enteric fistula (SAEF). With a prior history of infrarenal aortic ligation and the location of the SAEF being at the aortic sac, we explain the considerations for the techniques used and how we were able to stop the bleeding using percutaneous transarterial embolotherapy.

The Role of Interventional Radiology in the Diagnosis and Treatment of Pulmonary Arteriovenous Malformations

Pulmonary arteriovenous malformations (PAVMs) are uncommon, predominantly congenital direct fistulous connections between the pulmonary arteries and pulmonary veins, resulting in a right to left shunt. Patients with PAVMs are usually asymptomatic with lesions detected incidentally when radiological imaging is performed for other indications. In this review, we discuss the classification and radiological features of PAVMs as well as their treatment and follow-up options, with a particular focus on percutaneous endovascular techniques and the evolution of the available equipment for treatment.

The effectiveness of the Safety in Interventional Radiology (SIR) Shield in reducing droplet transmission and its effect on image quality and radiation dose

Objective:

To evaluate the efficacy of a barrier shield in reducing droplet transmission and its effect on image quality and radiation dose in an interventional suite.

Methods:

A human cough droplet visualisation model in a supine position was developed to assess efficacy of barrier shield in reducing environmental contamination. Its effect on image quality (resolution and contrast) was evaluated via image quality test phantom. Changes in the radiation dose to patient post-shield utilisation was measured.

Results:

Use of the shield prevented escape of visible fluorescent cough droplets from the containment area. No subjective change in line-pair resolution was observed. No significant difference in contrast-to-noise ratio was measured. Radiation dosage to patient was increased; this is predominantly attributed to the increased air gap and not the physical properties of the shield.

Conclusion:

Use of the barrier shield provided an effective added layer of personal protection in the interventional radiology theatre for aerosol generating procedures.

Advances in knowledge:

This is the first time a human supine cough droplet visualisation has been developed. While multiple types of barrier shields have been described, this is the first systematic practical evaluation of a barrier shield designed for use in the interventional radiology theatre.

Clinical predictors of internal carotid artery blowout in patients with radiated nasopharyngeal carcinoma

BACKGROUND

The primary objective is to identify clinical predictors of internal carotid artery (ICA) blowout in radiated nasopharyngeal carcinoma (NPC).

METHODS

Seventeen ICA blowouts, 14 external carotid artery (ECA) bleeds, and 60 controls were identified from January 1, 2007 to July 31, 2020. Multinomial logistic regression was performed to identify features predictive of ICA blowouts.

RESULTS

Headache was significantly more common among ICA blowouts than ECA bleeds and controls (58.8% vs. 7.1% vs. 6.7%, p < 0.001). The petrous skull base and sphenoid sinus lateral wall was eroded in all petrous and cavernous segment blowouts, respectively. Nasoendoscopy showing exposed clivus (OR 20.5, 95%CI 1.3-324.2) and computed tomography demonstrating skull base erosion (OR 17.8, 95%CI 1.0-311.0) were significantly associated with ICA blowouts compared to controls.

CONCLUSIONS

Findings of headache and skull base erosion on nasoendoscopy or imaging during NPC surveillance warrants prophylactic intervention to avoid an ICA blowout.

Thrombectomy for Primary Distal Posterior Cerebral Artery Occlusion Stroke: The TOPMOST Study

Importance

Clinical evidence of the potential treatment benefit of mechanical thrombectomy for posterior circulation distal, medium vessel occlusion (DMVO) is sparse.

Objective

To investigate the frequency as well as the clinical and safety outcomes of mechanical thrombectomy for isolated posterior circulation DMVO stroke and to compare them with the outcomes of standard medical treatment with or without intravenous thrombolysis (IVT) in daily clinical practice.

Design, Setting, and Participants

This multicenter case-control study analyzed patients who were treated for primary distal occlusion of the posterior cerebral artery (PCA) of the P2 or P3 segment. These patients received mechanical thrombectomy or standard medical treatment (with or without IVT) at 1 of 23 comprehensive stroke centers in Europe, the United States, and Asia between January 1, 2010, and June 30, 2020. All patients who met the inclusion criteria were matched using 1:1 propensity score matching.

Interventions

Mechanical thrombectomy or standard medical treatment with or without IVT.

Main Outcomes and Measures

Clinical end point was the improvement of National Institutes of Health Stroke Scale (NIHSS) scores at discharge from baseline. Safety end point was the occurrence of symptomatic intracranial hemorrhage and hemorrhagic complications were classified based on the Second European-Australasian Acute Stroke Study (ECASSII). Functional outcome was evaluated with the modified Rankin Scale (mRS) score at 90-day follow-up.

Results

Of 243 patients from all participating centers who met the inclusion criteria, 184 patients were matched. Among these patients, the median (interquartile range [IQR]) age was 74 (62-81) years and 95 (51.6%) were female individuals. Posterior circulation DMVOs were located in the P2 segment of the PCA in 149 patients (81.0%) and in the P3 segment in 35 patients (19.0%). At discharge, the mean NIHSS score decrease was -2.4 points (95% CI, -3.2 to -1.6) in the standard medical treatment cohort and -3.9 points (95% CI, -5.4 to -2.5) in the mechanical thrombectomy cohort, with a mean difference of -1.5 points (95% CI, 3.2 to -0.8; P = .06). Significant treatment effects of mechanical thrombectomy were observed in the subgroup of patients who had higher NIHSS scores on admission of 10 points or higher (mean difference, -5.6; 95% CI, -10.9 to -0.2; P = .04) and in the subgroup of patients without IVT (mean difference, -3.0; 95% CI, -5.0 to -0.9; P = .005). Symptomatic intracranial hemorrhage occurred in 4 of 92 patients (4.3%) in each treatment cohort.

Conclusions and Relevance

This study suggested that, although rarely performed at comprehensive stroke centers, mechanical thrombectomy for posterior circulation DMVO is a safe, and technically feasible treatment option for occlusions of the P2 or P3 segment of the PCA compared with standard medical treatment with or without IVT.

Significant aortic stenosis associated with poorer functional outcomes in patients with acute ischaemic stroke undergoing endovascular therapy

BACKGROUND AND AIM

Bi-directional feedback mechanisms exist between the heart and brain, which have been implicated in heart failure. We postulate that aortic stenosis may alter cerebral haemodynamics and influence functional outcomes after endovascular thrombectomy for acute ischaemic stroke. We compared clinical characteristics, echocardiographic profile and outcomes in patients with or without aortic stenosis that underwent endovascular thrombectomy for large vessel occlusion acute ischaemic stroke.

METHODS

Consecutive acute ischaemic stroke patients with anterior and posterior circulation large vessel occlusion (internal carotid artery, middle cerebral artery and basilar artery) who underwent endovascular thrombectomy were studied. Patients were divided into those with significant aortic stenosis (aortic valve area <1.5 cm2) and without. Univariate and multivariate analyses were employed to compare and determine predictors of functional outcomes measured by modified Rankin scale at three months.

RESULTS

We identified 26 (8.5%) patients with significant aortic stenosis. These patients were older (median age 76 (interquartile range 68-84) vs. 67 (interquartile range 56-75) years, p = 0.001), but similar in terms of medical comorbidities and echocardiographic profile. Rates of successful recanalisation (73.1% vs. 78.0%), symptomatic intracranial haemorrhage (7.7% and 7.9%) and mortality (11.5% vs. 12.6%) were similar. Significant aortic stenosis was independently associated with poorer functional outcome (modified Rankin scale >2) at three months (adjusted odds ratio 2.7, 95% confidence interval 1.1-7.5, p = 0.048), after adjusting for age, door-to-puncture times, stroke severity and rates of successful recanalisation.

CONCLUSION

In acute ischaemic stroke patients managed with endovascular thrombectomy, significant aortic stenosis is associated with poor functional outcome despite comparable recanalisation rates. Larger cohort studies are needed to explore this relationship further.

Left-sided valvular heart disease associated with poor functional outcomes in patients with acute ischaemic stroke undergoing endovascular thrombectomy

Background

Valvular heart disease (VHD) may be an important comorbidity acute ischemic stroke (AIS), adversely affecting cerebral haemodynamics and consequently limiting functional recovery after endovascular thrombectomy (EVT). We examined the clinical profile and outcomes in patients with or without VHD who underwent EVT for AIS.

Methods

Consecutive patients (n=224) who underwent EVT for AIS were examined. All patients underwent transthoracic echocardiography within 6 months of AIS. The patients were divided into those with left-sided VHD (at least moderate severity of aortic valve or mitral valve stenosis or regurgitation) and those without. Univariate and multivariate analyses were employed to compare clinical profile and outcomes.

Results

There were 47 (20.9%) patients with VHD. Of these, 31 (66.0%) had mitral regurgitation, 15 (31.9%) had aortic stenosis, 8 (17.0%) had aortic regurgitation and 6 (12.8%) had mitral stenosis. VHD patients had a higher prevalence of atrial fibrillation (68.1% vs 43.5%, p=0.003) compared to those without, but stroke severity was similar. They had higher prevalence of pathological left ventricular (LV) remodelling, with larger end-diastolic volume index (77.9±34.5 vs 61.1±19.9ml/m2, p&lt;0.001) and LV mass index (116.4±32.7 vs 99.8±32.2g/m2, p=0.002). Despite similar rates of recanalisation, VHD patients had poorer functional outcomes (mRS&gt;2) at 3 months (68.1% vs 50.3%, p=0.029). On multivariable analyses, VHD remained independently associated with poor functional outcomes (adjusted OR 2.42, 95% CI 1.08–5.43), after adjusting for age, stroke severity and recanalisation rates.

Conclusion

VHD may be associated with poorer functional outcomes in patients with AIS undergoing EVT, despite similar rates of successful recanalisation.

Ordinal shift analyses

Funding Acknowledgement

Type of funding source: None

Can a Stent Retriever Damage the JET 7 Reperfusion Catheter?

We encountered 2 separate instances of damage to JET 7 reperfusion catheters when they were used in conjunction with a stent retriever during mechanical thrombectomy. On both occasions, after 1 or 2 passes with a stent retriever, we found that the distal end of the catheter was frayed and it ballooned up on flushing with saline. This mechanical failure could potentially lead to serious complications; hence, it should be shared with fellow neurointerventionalists.

Left ventricular systolic dysfunction is associated with poor functional outcomes after endovascular thrombectomy

BACKGROUND

Endovascular thrombectomy (ET) has transformed acute ischemic stroke (AIS) therapy in patients with large vessel occlusion (LVO). Left ventricular systolic dysfunction (LVSD) decreases global cerebral blood flow and predisposes to hypoperfusion. We evaluated the relationship between LVSD, as measured by LV ejection fraction (LVEF), and clinical outcomes in patients with anterior cerebral circulation LVO who underwent ET.

METHODS

This multicenter retrospective cohort study examined anterior circulation LVO AIS patients from six international stroke centers. LVSD was measured by assessment of the echocardiographic LVEF using Simpson's biplane method of discs according to international guidelines. LVSD was defined as LVEF <50%. The primary outcome was defined as a good functional outcome using a modified Rankin Scale (mRS) of 0-2 at 3 months.

RESULTS

We included 440 AIS patients with LVO who underwent ET. On multivariate analyses, pre-existing diabetes mellitus (OR 2.05, 95% CI 1.24 to 3.39;p=0.005), unsuccessful reperfusion (Treatment in Cerebral Infarction (TICI) grade 0-2a) status (OR 4.21, 95% CI 2.04 to 8.66; p<0.001) and LVSD (OR 2.08, 95% CI 1.18 to 3.68; p=0.011) were independent predictors of poor functional outcomes at 3 months. On ordinal (shift) analyses, LVSD was associated with an unfavorable shift in the mRS outcomes (OR 2.32, 95% CI 1.52 to 3.53; p<0.001) after adjusting for age and ischemic heart disease.

CONCLUSION

Anterior circulation LVO AIS patients with LVSD have poorer outcomes after ET, suggesting the need to consider cardiac factors for ET, the degree of monitoring and prognostication post-procedure.

SIR HELMET (Safety In Radiology HEalthcare Localised Metrological EnviromenT): a low-cost negative-pressure isolation barrier for shielding MRI frontline workers from COVID-19 exposure

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Low cost reusable acrylic and silicone rubber barrier shield design.

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Localised negative pressure environment simulating isolation rooms.

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Does not affect MRI image quality even on the most sensitive sequences.

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Additional personal protective equipment for frontline healthcare professionals.

How to do it: value-driven sharp recanalization of central vein occlusion

Patients on haemodialysis are susceptible for central vein occlusions, which can result in debilitating clinical consequences. These may be resistant to conventional revascularization with guidewire and catheter technique. Value-driven sharp recanalization of central vein occlusion is depicted as a safe and affordable option.

Challenges in the Management of a Ruptured Bihemispheric Posterior Inferior Cerebellar Artery Aneurysm

BACKGROUND

Bihemispheric posterior inferior cerebellar artery (PICA) is a rare anatomic variant wherein a single PICA supplies both cerebellar hemispheres. Inasmuch as it is the only PICA, treatment of aneurysms arising from this anatomic variant is more complex. We present a case of a ruptured bihemispheric PICA aneurysm and the challenges encountered in its management.

CASE DESCRIPTION

A 54-year-old man presented with giddiness and nausea. Otherwise, he was neurologically intact. Computed tomography of the brain showed a right cerebellar hematoma and intraventricular hemorrhage. Cerebral angiography revealed a dissecting aneurysm in the retromedullary segment of a right bihemispheric PICA with a prominent saccular component. Initially, the patient refused to undergo any invasive treatment. However, when a follow-up angiogram showed an increase in the size of the aneurysm sac, he consented to treatment. Although parent vessel occlusion (PVO) was the clinical recommendation, in view of the patient's apprehensions, only the saccular component of the aneurysm was coil embolized without sacrifice of the parent vessel. Fifteen days after the coiling, there was a rebleed from this dissecting aneurysm, which was treated with PVO followed by suboccipital craniectomy. The patient made a reasonable recovery, and his modified Rankin score was 1 at his 6-month follow-up visit.

CONCLUSIONS

In dissecting aneurysms of a bihemispheric PICA, isolated endosaccular occlusion provides uncertain protection from a rebleed, whereas a more reliable treatment with PVO carries an unpredictable risk of ischemic complications. The risks of a PVO may be rationalized as a life-saving measure; however, the subsequent threshold for posterior fossa decompression should be low.

Solid pseudopapillary neoplasm of the pancreas: CT imaging features and radiologic-pathologic correlation

PURPOSE

We aimed to evaluate the imaging features of solid pseudopapillary neoplasm (SPN) of the pancreas with an emphasis on radiologic-pathologic correlation.

METHODS

Ten patients (all female; mean age, 32 years) with histologic or cytologic diagnosis of SPN encountered between January 2007 and December 2013 were included in this study. Preoperative computed tomography (CT) images were reviewed for location, attenuation, enhancement pattern, margin, shape, size, morphology, presence of capsule and calcification. CT appearances were correlated with histopathologic findings.

RESULTS

Tumors in the distal pancreatic body and tail had a tendency to be larger (mean size 12.6 cm vs. 4.0 cm). Six of the nine tumors that were resected had a fibrous pseudocapsule at histology, five of which could be identified on CT scan. Eight lesions had mixed hypoenhancing solid components and cystic areas corresponding to tumor necrosis and hemorrhage. The two smallest lesions were purely solid and nonencapsulated. Varied patterns of calcification were seen in four tumors. Three of the four pancreatic tail tumors invaded the spleen. At a median follow-up of 53 months, there was no evidence of recurrence in the nine patients who underwent surgical resection of the tumor.

CONCLUSION

A mixed solid and cystic pancreatic mass in a young woman is suggestive of SPN. However, smaller lesions may be completely solid. Splenic invasion can occur in pancreatic tail SPNs; however, in this series it did not adversely affect the long-term outcome.

Preoperative embolization in spinal tumour surgery: Enhancing its effectiveness

We conducted a retrospective review of 221 patients, who underwent spinal oncologic surgery at a tertiary university hospital between 2005 and 2014; in order to identify and validate factors that influence the impact of preoperative embolization of spinal tumours on outcome measures of blood loss and transfusion requirements in spinal oncologic surgery. We also focused on primary tumour type and type of spinal surgery performed. Patients' electronic and physical records were reviewed to provide demographic data, tumour characteristics, embolization techniques and surgical procedure details. These data were analysed against recorded outcome measures of blood loss (absolute volume and haemoglobin reduction) and transfusion requirements. Forty eight patients who received preoperative embolization were compared against 173 patients who did not. There was a tendency towards reduced blood loss and transfusion requirements in embolized spinal metastases from HCC and thyroid; as well as primary spine tumours, though the differences were not significant. Total embolization of arterial supply to spinal tumours resulted in significantly less blood loss as compared to partial or subtotal embolization. In addition, median blood loss was lower in patients receiving a more proximal embolization and in patients who underwent surgery between 13 and 24h post-embolization despite the insignificant difference. To conclude, preoperative spinal tumour embolization is likely to be effective in reducing blood loss if a total embolization is performed 13-24h prior to the surgery. Similarly, the impact of embolization is likely to be more profound in metastases from HCC, thyroid and primary spine tumours.

WEB in Partially Thrombosed Intracranial Aneurysms: A Word of Caution

Despite the proved safety and efficacy of Woven EndoBridge (WEB) flow disruption in conventional intracranial saccular aneurysms, the literature on its use in partially thrombosed intracranial aneurysms is scarce. We report a series of 4 patients in whom partially thrombosed intracranial aneurysms were treated with the WEB. The 2 patients who received additional intraluminal treatment with conventional stents made a good clinical recovery. Meanwhile, those patients who were treated with the WEB alone had fatal rupture of the aneurysm at short- to medium-term follow-up. This small, select case series demonstrates that WEB placement with adjunctive stent placement may be an effective treatment in the management of partially thrombosed intracranial aneurysms, which merits further validation. However, exclusive intrasaccular flow disruption may have an adverse influence on the natural history of this disease.

Post hysterectomy intravenous leiomyomatosis: multimodality imaging appearances

No abstract available.

Expectations from imaging for pre-transplant evaluation of living donor liver transplantation

Living donor liver transplant (LDLT) is a major surgical undertaking. Detailed pre-operative assessment of the vascular and biliary anatomy is crucial for safe and successful harvesting of the graft and transplantation. Computed tomography (CT) and magnetic resonance imaging (MRI) are currently the imaging modalities of choice in pre-operative evaluation. These cross-sectional imaging techniques can reveal the vascular and biliary anatomy, assess the hepatic parenchyma and perform volumetric analysis. Knowledge of the broad indications and contraindications to qualify as a recipient for LDLT is essential for the radiologist reporting scans in a pre-transplant patient. Similarly, awareness of the various anatomical variations and pathological states in the donor is essential for the radiologist to generate a meaningful report of his/her observations. CT and MRI have largely replaced invasive techniques such as catheter angiography, percutaneous cholangiography and endoscopic retrograde cholangiopancreatography. In order to generate a meaningful report based on these pre-operative imaging scans, it is also mandatory for the radiologist to be aware of the surgeon’s perspective. We intend to provide a brief overview of the common surgical concepts of LDLT and give a detailed description of the minimum that a radiologist is expected to seek and report in CT and MR scans performed for LDLT related evaluation.

Multi-detector computed tomography in the diagnosis and management of acute aortic syndromes

Acute aortic syndrome (AAS) is a spectrum of conditions, which may ultimately progress to potentially life-threatening aortic rupture. This syndrome encompasses aortic dissection (AD), intramural haematoma, penetrating atherosclerotic ulcer and unstable thoracic aortic aneurysms. Multi-detector CT (MDCT) is crucial for the diagnosis of AAS, especially in the emergency setting due to its speed, accuracy and ready availability. This review attends to the value of appropriate imaging protocols in obtaining good quality images that can permit a confident diagnosis of AAS. AD is the most commonly encountered AAS and also the one with maximum potential to cause catastrophic outcome if not diagnosed and managed promptly. Hence, this review briefly addresses certain relevant clinical perspectives on this condition. Differentiating the false from the true lumen in AD is often essential; a spectrum of CT findings, e.g., “beak sign”, aortic “cobwebs” that allows such differentiation have been described with explicit illustrations. The value of non enhanced CT scans, especially useful in the diagnosis of an intramural hematoma has also been illustrated. Overlap in the clinical and imaging features of the various conditions presenting as AAS is not unusual. However, on most instances MDCT enables the right diagnosis. On select occasions MRI or trans-esophageal echocardiography may be required as a problem solving tool.

Yttrium-90 radioembolization of liver tumors: what do the images tell us?

Transarterial radioembolization (TARE) with yttrium 90 microspheres is an increasingly popular therapy for both primary and secondary liver malignancies. TARE entails delivery of β-particle brachytherapy and embolization of the tumor vasculature. The consequent biological sequelae are distinct from those of other transarterial therapies for liver tumors, as reflected in the often baffling post-treatment imaging features. As the clinical use of TARE is increasing, more diverse post-treatment radiological findings are encountered with variable overlap among treatment response, residual disease, reactionary changes and complications. Thus, post-TARE image interpretation is challenging. This review provides a comprehensive description of the different findings seen in post-treatment scans, with the aim of facilitating appropriate radiological interpretation of post-TARE pathologic changes, notwithstanding their existing limitations.

Imaging paradigms in assessment of rectal carcinoma: loco-regional and distant staging

The role of imaging in the management of rectal malignancy has progressively evolved and undergone several paradigm shifts. Unlike a few decades ago when the role of a radiologist was restricted at defining the longitudinal extent of the tumour with barium enema, recent advances in imaging techniques permit highly accurate locoregional and distant staging of the disease as well as prognostication on those who are likely to have a postoperative recurrence. Computed tomography (CT) has always been the mainstay of imaging when evaluating for distant metastasis, with the advent of positron emission tomography/CT improving its specificity. In rectal malignancy, it is the local extent of the disease that often influences the surgical decision making and need for neoadjuvant therapy. Although endoscopic ultrasound has been the traditional technique for determining the depth of tumour invasion, over the last decade magnetic resonance imaging (MRI) has emerged as a very effective tool for accurate T-staging. This review intends to address the status of various imaging modalities and their advantages and limitations in detection, pretreatment staging, and assessment of therapeutic efficacy in rectal cancer, with emphasis on MRI of high spatial resolution.

Endovascular treatment of isolated systemic arterial supply to normal lung with coil and glue embolisation

Surgery is the standard treatment for the extremely rare pathology of isolated anomalous systemic arterial supply to normal lung (ISSNL). We describe our experience with this anomaly in a 29-year-old male presenting with recurrent haemoptysis that was successfully treated with a combination of metallic coils and cyanoacrylate glue. In addition to contributing to the extremely limited data on endovascular therapeutic options in ISSNL, we also intend to raise the awareness among endovascular therapists of the need to be cautious ofand preserve the radiculomedullary/pial branches arising from an anomalous artery before embolising it.

Fluoroscopy-guided, transcervical, selective salpingography and fallopian tube recanalisation

This study is a retrospective review of the transcervical fluoroscopy-guided fallopian tube recanalisation (FTR) procedures done in a multi-ethnic south-east Asian population, over 9 years. A total of 100 patients with infertility and documented proximal tubal obstruction (PTO) were referred for FTR. On-table hysterosalpingography under sedation demonstrated true PTO in 96 patients. At selective-salpingography, the PTO cleared in 16 patients; 78 required FTR and two had fimbrial blockage. The technical success rate of FTR was 86.8% and the post-FTR pregnancy rate was 36.84% at a mean follow-up interval of 12.2 months. There were no major, immediate procedure-related complications. There was an ectopic pregnancy in a single treated patient. Fluoroscopy-guided FTR is a safe treatment option in patients with infertility from PTO, with high technical success rate, low complication rate and increased chances of pregnancy; therefore it should be preferred before attempting more expensive and resource-intensive procedures.

Thyroid nodules: risk stratification for malignancy with ultrasound and guided biopsy

Replacing palpating fingers with an ultrasound (US) probe has resulted in an epidemic of thyroid nodules. Despite the high prevalence of thyroid nodules in the general population, thyroid malignancy is rare. Although no imaging modality can accurately predict the nature of every nodule, high-resolution US is the most sensitive, easily available and cost-effective diagnostic test available to detect thyroid nodules, measure their dimensions and identify their structure. The presence of calcifications, irregular spiculated outline, hypoechogenicity in a solid nodule, chaotic intranodular vascularity and an elongated shape are well-known US features of malignancy in thyroid nodules. Cervical lymph node metastasis and extrathyroidal extension of a thyroid nodule are highly specific for malignancy but seen infrequently. Spongiform nodules, purely or predominantly cystic nodules, nodules with well-defined hypoechoic halo and echogenic as well as isoechoic nodules are usually benign. None of the US characteristics have 100% accuracy in detecting or excluding malignancy. Fine-needle biopsy is currently the best triage test for pre-operative evaluation of a thyroid nodule. There is no significant difference in the risk for malignancy between palpable and non-palpable nodules and size is not a reliable indicator for their malignant potential. The best tool for risk stratification for malignancy in thyroid nodules is US and guided biopsy of nodules with suspicious imaging features. This is especially relevant in patients with multinodular goitre.

Cystic hepatic mesenchymal hamartoma: the role of radiology in diagnosis and perioperative management

A 13-month-old male presented with large hepatic mass that was confirmed diagnostically to be a cystic hepatic mesenchymal hamartoma. The sieve-like appearance of the solid components of the mass, as seen at ultrasonography, and findings of dynamic post-contrast MRI are highlighted here. Beyond diagnostic imaging, we extended our role in patient management through ultrasound-guided intra-operative aspiration of fluid from the cystic components of the tumour to reduce its volume and thereby facilitate surgical resection.

Radiology of osteoporosis

Bone densitometric studies have shown that osteoporosis is a result of prolonged, slow bone loss and that the pattern of loss is different for trabecular and cortical bone. Structurally-insufficient osteoporotic bone is predisposed to fractures. Among the clinically manifest osteoporotic fractures, distal radius leads the list, followed by hip, spine, and proximal humerus. This article examines the use of conventional radiography as well as other imaging-based modalities for the evaluation of osteoporosis and associated fractures in the axial and appendicular skeleton.

Imaging characteristics of schwannoma of the cervical sympathetic chain: a review of 12 cases

BACKGROUND AND PURPOSE

SCSCs are rare. This study reviews our experience with CT and MR imaging of SCSCs.

MATERIALS AND METHODS

We retrospectively reviewed the CT and MR imaging studies as well as clinical data of 12 patients (6 men, 6 women; mean age, 41 years; range, 27-55 years) with surgicopathologic evidence of SCSC, referred to our institution between January 1999 to October 2008. Images were evaluated with respect to the location, number, morphology, attenuation/signal intensity, enhancement characteristics, and patterns of mass effect of the schwannomas.

RESULTS

The schwannomas were solitary, well-circumscribed, and medial to the carotid sheath. Seven were hypoattenuated to skeletal muscle on CT with poor postcontrast enhancement, 4 were isoattenuated, and a single lesion showed intense heterogeneous enhancement. At MR imaging, they were heterogeneously bright on T2WI with intense inhomogeneous postgadolinium enhancement. The ICA was displaced anteriorly in 9 patients with a component of lateral displacement in 8 of these patients. The ICA was in a neutral position in 2 patients and posterolaterally displaced in 1 patient. A single patient demonstrated separation of the ICA and IJV. There was splaying of the carotid bifurcation in 4 patients.

CONCLUSIONS

We present the patterns of mass effect and the spectrum of CT and MR imaging characteristics of SCSC, including certain observations that are infrequently described in the published literature.

Determination of trace concentrations of elements in high purity tellurium by radio frequency glow discharge optical emission spectrometer (RF-GDOES)

A method was established for the determination of trace impurities in high purity tellurium (Te) 99.9999 (6N) by radio frequency glow discharge optical emission spectrometry (RF-GDOES). The optimized parameters are power, argon pressure, pre-integration time, analysis time and selection of wavelength. Nine elements Se, Ca, Mg, Si, Fe, Cr, Cu, Ni and Pb were analysed in 6N Te, out of which only three elemental peaks (Se, Ca, and Mg) were detected and the remaining six elements ( Si, Fe, Cr, Cu, Ni and Pb) were below detection levels. Finally, the method was evaluated by the analysis of the above traces using inductively coupled plasma mass spectrometry (ICP-MS) and was found to be satisfactory. The detection limits for most of the elements were below 10 ng/g and R.S.D. was around 10%, which indicated that this method could fully satisfy the requirements for the trace analysis in high purity Te metal.