Multisystem Imaging Manifestations of Kidney Failure

Kidney failure (KF) refers to a progressive decline in glomerular filtration rate to below 15 ml/min per 1.73 m2, necessitating renal replacement therapy with dialysis or renal transplant. The hemodynamic and metabolic alterations in KF combined with a proinflammatory and coagulopathic state leads to complex multisystemic complications. The imaging hallmark of systemic manifestations of KF is bone resorption caused by secondary hyperparathyroidism. Other musculoskeletal complications include brown tumor, osteosclerosis, calcinosis, soft-tissue calcification, and amyloid arthropathy. Cardiovascular complications and infections are the leading causes of death in KF. Cardiovascular complications include accelerated atherosclerosis, cardiomyopathy, pericarditis, myocardial calcinosis, and venous thromboembolism. Neurologic complications such as encephalopathy, osmotic demyelination, cerebrovascular disease, and opportunistic infections are also frequently encountered. Pulmonary complications include edema and calcifications. Radiography and CT are used in assessing musculoskeletal and thoracic complications, while MRI plays a key role in assessing neurologic and cardiovascular complications. CT iodinated contrast material is generally avoided in patients with KF except in situations where the benefit of contrast-enhanced CT outweighs the risks and in patients already undergoing maintenance dialysis. At MRI, group II gadolinium-based contrast material can be safely administered in patients with KF. The authors discuss the extrarenal systemic manifestations of KF, the choice of imaging modality in their assessment, and imaging findings of complications. ©RSNA, 2024 Supplemental material is available for this article.

Cerebral Venous Thrombosis in Pediatric Age: Risk Factors and Prognosis

INTRODUCTION

 Cerebral venous thrombosis (CVT) is a rare but potentially fatal disease in pediatric age with an important morbimortality. In adults several factors have been associated with worse outcomes, however there are still few studies in children. This study aims to identify risk factors associated with clinical manifestations and long-term sequelae in pediatric CVT.

METHODS

 Retrospective analysis of pediatric inpatients admitted to a tertiary-care hospital due to CVT between 2008 and 2020.

RESULTS

 Fifty-four children were included, 56% male, median age of 6.5 years (9 months-17.3 years). Permanent risk factors were identified in 13 patients (malignancy, 8; hematologic condition, 5) and transient risk factors in 47, including head and neck infections (57%) and head trauma (15%). Multiple venous sinuses involvement was present in 65% and the deep venous system was affected in four patients. Seventeen percent had intracranial hemorrhage and 9% cerebral infarction. Sixty-four percent of patients with multiple venous sinuses involvement presented with severe clinical manifestations: impaired consciousness, intracranial hypertension, acute symptomatic seizures or focal deficits. Regarding long-term prognosis, six patients had major sequelae: epilepsy (n = 3), sensory motor deficits (n = 2), and cognitive impairment (n = 3). Permanent risk factors were associated with severe clinical manifestations (p = 0.043). Cerebral infarction and intracranial hemorrhage were associated with major sequelae (p = 0.006 and p = 0.03, respectively, adjusted for age and sex).

CONCLUSION

 Permanent risk factors, involvement of multiple venous sinuses, intracranial hemorrhage, and cerebral infarction, were related to worse prognosis. Detection and early management of risk factors may limit CVT extension and reduce its morbimortality.

Uncommon Causes of Nontraumatic Intracerebral Hemorrhage

Nontraumatic intracerebral hemorrhage is an important health issue. Although common causes such as hypertension and cerebral amyloid angiopathy predominantly affect the elderly, there exists a spectrum of uncommon etiologies that contribute to the overall incidence of intracerebral hemorrhage. The identification of these rare causes is essential for targeted clinical management, informed prognostication, and strategic secondary prevention where relevant. This topical review explores the uncommon intracerebral hemorrhage causes and provides practical clues for their clinical and imaging identification. By expanding the clinician's differential diagnosis, this review aims to bridge the gap between standard intracerebral hemorrhage classification systems and the nuanced reality of clinical practice.

Cerebral venous thrombosis

Cerebral venous thrombosis is part of the so-called thrombosis in unusual sites. It is defined as an occlusion in the cerebral venous territory. Its incidence is progressively increasing, especially in developing countries. It is more frequently observed in young women, with hormonal factors such as pregnancy or hormonal contraception being significant risk factors in the development of this condition. The clinical presentation will depend fundamentally on the topography of the thrombosis, with a confirmatory diagnosis based mainly on imaging tests. The treatment generally consists of anticoagulation, and other options may be considered depending on the severity of the case. Overall, the prognosis is better than that of other intracranial vascular disorders. This review describes the current evidence available regarding cerebral venous thrombosis.

Neuroimaging of Neonatal Stroke: Venous Focus

Perinatal venous infarcts are underrecognized clinically and at imaging. Neonates may be susceptible to venous infarcts because of hypercoagulable state, compressibility of the dural sinuses and superficial veins due to patent sutures, immature cerebral venous drainage pathways, and drastic physiologic changes of the brain circulation in the perinatal period. About 43% of cases of pediatric cerebral sinovenous thrombosis occur in the neonatal period. Venous infarcts can be recognized by ischemia or hemorrhage that does not respect an arterial territory. Knowledge of venous drainage pathways and territories can help radiologists recognize characteristic venous infarct patterns. Intraventricular hemorrhage in a term neonate with thalamocaudate hemorrhage should raise concern for internal cerebral vein thrombosis. A striato-hippocampal pattern of hemorrhage indicates basal vein of Rosenthal thrombosis. Choroid plexus hemorrhage may be due to obstruction of choroidal veins that drain the internal cerebral vein or basal vein of Rosenthal. Fan-shaped deep medullary venous congestion or thrombosis is due to impaired venous drainage into the subependymal veins, most commonly caused by germinal matrix hemorrhage in the premature infant and impeded flow in the deep venous system in the term infant. Subpial hemorrhage, an underrecognized hemorrhage stroke type, is often observed in the superficial temporal region, and its cause is probably multifactorial. The treatment of cerebral sinovenous thrombosis is anticoagulation, which should be considered even in the presence of intracranial hemorrhage. ©RSNA, 2024 Test Your Knowledge questions in the supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Clinicoradiological Features and Long-term Cognitive and Functional Outcome in Patients with Deep Cerebral Venous Thrombosis

Background

Deep cerebral venous thrombosis (DCVT) can have long-term functional and cognitive sequelae. Although literature exists on cognitive impairment after arterial stroke, cognitive sequelae after cerebral venous thrombosis (CVT) are much less studied.

Methods

Clinical records of 29 patients diagnosed with DCVT were reviewed. The Modified Telephonic Interview for Cognitive Status (TICS-M) was adapted and validated in the regional language (Kannada) and applied to 18 patients with DCVT, at a mean follow-up duration of 5.32 years. Screening for depression was done via telephonic Patient Health Questionnaire-9 (PHQ-9)-Kannada version, and functional status was screened by applying the modified Rankin Scale (mRS).

Results

DCVT had a mortality rate of 10.34% due to acute complications. mRS scores of 0-1 were achieved at follow-up in all patients who survived. Receiver operating characteristic (ROC) analysis revealed a cutoff of ≤44.5 (maximum score of 49) for the diagnosis of cognitive impairment via TICS-M (Kannada version) in DCVT patients. Evidence of cognitive dysfunction was seen in eight patients (42.10%), and three patients (16.66%) had evidence of depression.

Conclusions

Survivors of acute DCVT can potentially have long-term cognitive sequelae. Screening for cognitive dysfunction, depression, and functional status can be effectively done using telephonically applied scales that are adapted to the local language. Neuropsychological evaluation and early cognitive rehabilitation can be initiated for patients in whom deficits are identified on cognitive screening.

Translabyrinthine Craniotomy Is Associated with Higher Risk of Asymptomatic Dural Venous Sinus Thrombosis in Vestibular Schwannoma Resection

OBJECTIVE

Characterize the incidence, risk factors, and patient outcomes of dural venous sinus thrombosis identified on postoperative imaging after retrosigmoid or translabyrinthine craniotomy for vestibular schwannoma resection.

STUDY DESIGN

Retrospective cohort study.

SETTING

Single tertiary academic referral center.

PATIENTS

Eighty-one patients 19 to 82 years of age with vestibular schwannomas, 58% female.

INTERVENTIONS

Retrosigmoid or translabyrinthine craniotomy with postoperative magnetic resonance imaging/magnetic resonance venography.

MAIN OUTCOME MEASURES

Association between operative approach, age, sex, body mass index, tumor size, dominant sinus, operative time, laterality, and perioperative cerebrospinal fluid (CSF) leaks with rate of thrombosis.

RESULTS

Translabyrinthine craniotomy was associated with the highest relative risk of thrombosis (odds ratios [OR] = 19.82, 95% confidence interval [CI] = 1.75-224, p = 0.007), followed by male sex (OR = 5.53, 95% CI = 1.63-18.8, p = 0.035). Other patient and demographic risk factors were not associated with increased rates of dural venous thrombosis, nor was there an association with postoperative CSF leak. 81% (25/31) of thrombi had resolved within 3 years of surgery.

CONCLUSIONS

Translabyrinthine approach and male sex most strongly predicted postoperative dural venous thrombosis after postauricular craniotomy for vestibular schwannoma resection.

PROFESSIONAL PRACTICE GAP AND EDUCATIONAL NEED

Better understanding of risk factors and management of dural venous thrombosis after vestibular schwannoma surgery.

LEARNING OBJECTIVE

Characterize clinically significant risk factors for dural venous thrombosis in vestibular schwannoma surgery.

DESIRED RESULT

Identification of patient and operative risk factors for dural venous thrombosis.

LEVEL OF EVIDENCE

III.

INDICATE IRB OR IACUC

Exempt.

Venous Pathologies and Interventions of the Head

Intracranial venous pathologies are a historically underrecognized group of disorders that can have a devastating impact on patients. Despite advancements in peripheral venous disorders and arterial neurointerventions, intracranial venous pathologies have received comparatively little attention. Understanding the anatomy, physiology, clinical relevance, and treatment options of intracranial venous pathologies is fundamental to evolving therapies and research priorities. This article provides an overview of major intracranial venous pathologies, the respective pathophysiologies, and treatment options.

Current Evaluation of Intracerebral Hemorrhage

Advanced imaging is currently critical in diagnosing, predicting, and managing intracerebral hemorrhage. MD CT angiography has occupied the first line of evaluating patients with a clinical diagnosis of a stroke, given its rapid acquisition time, high resolution of vascular structures, and sensitivity for secondary causes of ICH.

Increased cerebrospinal fluid pressure and nephrotic syndrome: A case report and literature review

OBJECTIVE

To analyze how nephrotic syndrome (NS) correlates to increased intracranial pressure (ICP), and to present a case of an adult patient whose initial manifestation of NS was cephalalgia, with the later identification of raised ICP.

METHODS

Data were retrospectively retrieved from the patient's record, and a literature search with the keywords "nephrotic syndrome", "intracranial hypertension" and "headache" was conducted in PubMed and Embase.

RESULTS

This is a rare description of co-occurrence of NS and raised ICP in a 48-year-old man, in which ICP normalizes after NS remits. There is no known cause for the raised ICP of our patient. Ten reports (n = 13) of concomitant occurrence of increased ICP and NS were described in the literature, both in children and adults. Cerebral venous thrombosis (CVT) was the most likely underlying cause for the majority of them. For one patient, the underlying cause was meningoencephalitis. Finally, in one case, the cause is unknown, but CVT was not discarded.

CONCLUSION

The early suspicion of elevated ICP is warranted in patients with new-onset headache and NS. It is possible that NS could both directly and indirectly lead to increased ICP through yet unknown mechanisms, although this direct causal relationship cannot be currently established.

D-Dimer Level Associated with Amount of Sinus involvement Using Digital Subtraction Angiography on Cerebral Venous Thrombosis Patients

Background

Cerebral venous sinus thrombosis (CVST) is a form of the cerebrovascular disease characterized by varying degrees of obstruction of veins and cerebral sinuses caused by thrombus. Diagnosis is incredibly challenging due to the wide variety of symptoms and the distinct radiological aspects of affected vessels. In patients with venous thrombosis, the presence of D-Dimer is used as an indicator of the presence of endogenous fibrinolysis. D-Dimer is a by-product of fibrin polymer fragmentation.

Objective

To investigate the relationship between the level of D-Dimer and the number of sinuses in CVST by Digital Subtraction Angiography (DSA).

Methods

Retrospective data from September 2021 to September 2022 were used in this analytical observational with a cross-sectional study design. Chi-Square is used for data processing relationship analysis.

Results

Out of the 54 subjects with elevated levels of D-Dimer, 38 (70.4%) are females, whereas 16 (29.6%) are males. High levels of D-Dimer have been related to a greater risk of sinus thrombosis (p < 0.001). D-Dimer levels were similarly shown to rise in conjunction with the number of sinuses most severely damaged by thrombosis. The most common site for thrombosis to develop in this study were the left sigmoid and left transverse sinuses. Most risk factors were hormonal.

Conclusion

There is a statistically significant relationship between an increase in the D-Dimer level and the greater number of sinuses involved as determined by DSA in individuals diagnosed with CVST.

Association between Dural AVFs and Cerebral Venous Thrombosis

BACKGROUND AND PURPOSE

Recent reports suggest an association between dural AVFs and cerebral venous thrombosis. We aimed to investigate the specific temporal and anatomic association between the 2 conditions.

MATERIALS AND METHODS

A consecutive cohort of adult patients with dural AVFs was seen at Amsterdam University Medical Centers (2007-2020). An experienced neuroradiologist re-evaluated the presence and imaging characteristics of dural AVFs and cerebral venous thrombosis on all available imaging. The temporal (previous/concurrent/subsequent) and anatomic (same/adjacent/unrelated venous sinus or vein) association between dural AVFs and cerebral venous thrombosis was determined.

RESULTS

Among 178 patients with dural AVFs, the mean age was 58.3 (SD, 13.2) years and 85 (48%) were women. Of 55 patients (31%) with cerebral venous thrombosis, 34 (62%) were women. Four patients (7%) had cerebral venous thrombosis before the development of a dural AVF, 33 (60%) had cerebral venous thrombosis at the time of dural AVF diagnosis (concurrent), and 18 (33%) developed cerebral venous thrombosis during follow-up after conservative treatment. The incidence rate of cerebral venous thrombosis after a dural AVF was 79 per 1000 person-years (95% CI, 50-124). In 45 (82%) patients with dural AVFs and cerebral venous thrombosis, the thrombosis was located in the same venous sinus as the dural AVF, whereas in 8 (15%) patients, thrombosis occurred in a venous sinus adjacent to the dural AVF.

CONCLUSIONS

One-third of patients with a dural AVF in this study were diagnosed with cerebral venous thrombosis. In almost two-thirds of patients, cerebral venous thrombosis was diagnosed prior to or concurrent with the dural AVF. In 97% of patients, there was an anatomic association between the dural AVF and cerebral venous thrombosis. These data support the hypothesis of a bidirectional association between the 2 diseases.

Neuroimaging findings in hospitalized patients with COVID-19

Background

Variable neuroimaging findings have been reported in patients with coronavirus disease 2019 (COVID-19). In addition to respiratory symptoms, many neurologic manifestations of COVID-19 are increasingly reported and variable neuroimaging findings have been observed in patients with COVID-19. Our aim was to describe findings observed in hospitalized patients with COVID-19, presenting with acute neurologic manifestations and undergoing computed tomography (CT) or magnetic resonance imaging (MRI) of the brain.

Methods

We performed a retrospective study involving patients with laboratory-confirmed SARS-COV-2 infection, admitted to our hospital between July 1 and December 30, 2020. Patients who presented with acute neurologic symptoms and required neuroimaging were only included in the study. Neuroimaging examinations were evaluated for the presence of, infarction, hemorrhage and encephalopathy. The frequency of these findings was correlated with clinical variables, including presence of comorbidities, requirement for intensive care unit admission, and duration between admission and onset of neurologic signs and symptoms as documented in the hospital medical records.

Results

A total of 135 patients underwent at least one cross-sectional imaging of the brain, the median age of these patients was 63 years, and 72% were men. Disturbed level of consciousness was the most common neurologic symptom (80.7%). Acute neuroimaging findings were found in 34 patients (25.2%) including; acute ischemic infarcts (16/135; 11.9%), intracranial hemorrhages (9/135, 6.7%), cerebral venous thrombosis (2/135; 1.5%), posterior reversible encephalopathy syndrome (1/135; 0.7%), and hypoxic-ischemic encephalopathy (6/135, 4.4%). There was no statistically significant difference in patient age (p = 0.062), sex (0.257), presence of comorbidities (p = 0.204), intensive care unit admission (p = 0.326) and duration between admission and onset of neurologic signs and symptoms (p = 0.755), in patients with positive versus negative neuroimaging studies.

Conclusions

Our study showed that cerebrovascular complications, ischemic and hemorrhagic were the most frequent imaging finding in hospitalized patients with COVID-19. Knowledge about these potentially serious complications can help optimize management for these patients.

Cerebral venous sinus thrombosis in pregnancy and puerperium: A comprehensive review

Cerebral venous sinus thrombosis (CVST) is a distinct neurological emergency caused by occlusion, either partial or complete, of the dural venous sinus and/or the cerebral veins. It occurs more frequently in women during pregnancy and puerperium as compared to the general population. The clinical diagnosis is difficult in some cases due to its variable clinical presentation with numerous causes and risk factors. The diagnosis can be made at an early stage if clinical suspicion is high with the help of advanced neuroimaging techniques that were developed recently. Early therapeutic intervention using anticoagulants allows for preventing complications and improving outcomes. In this article, we review the topic of CVST in pregnancy and the postpartum period with an emphasis on its epidemiology, pathophysiology, clinical presentation, and treatment. We also elaborate on several practical points that are important to the treating team. This review will help obstetricians, neurologists, and emergency physicians diagnose affected pregnant women as early as possible to provide prompt treatment and avoid adverse outcomes.

Sinovenous outflow in lateral sinus dural arteriovenous fistulas after stereotactic radiosurgery: a retrospective longitudinal imaging study

PURPOSE

To investigate sinovenous outflow restriction (SOR) in lateral sinus dural arteriovenous fistulas (LSDAVFs) after Gamma Knife radiosurgery (GKRS) and its association with complete obliteration.

METHODS

We retrospectively (1995-2019) enrolled 39 patients with LSDAVFs who had undergone GKRS alone and evaluated their angiography and magnetic resonance imaging (MRI) before and after GKRS. The LS conduits ipsilateral and contralateral to the DAVFs were scored using a 5-point scoring system, with scores ranging from 0 (total occlusion) to 4 (fully patent). SOR was defined by a conduit score < 2. Demographics, imaging features, and outcomes were compared between patients with and without ipsilateral SOR after GKRS. Logistic regression analysis was performed to estimate the odds ratio (OR) for obliteration with the imaging findings.

RESULTS

After a median angiographic follow-up of 28 months for the 39 patients, the ipsilateral LS became more restrictive (median conduit score before and after GKRS: 2 vs. 1, p = .011). Twenty-one patients with ipsilateral SOR after GKRS had a significantly lower obliteration rate (52.4% vs. 94.4%, p = .005) than those without SOR. Follow-up SOR was independently associated with a lower obliteration rate (OR 0.05, p = .017) after adjustment for age, cortical venous reflux, and absent sinus flow void on MRI.

CONCLUSION

This study demonstrates a restrictive change of outflow in LSDAVFs after GKRS and a lower obliteration rate in patients with SOR. Follow-up imaging for SOR may help predict outcomes of these patients.

Deep venous sinus thrombosis with right thalamic infarction in a young patient after COVID-19 vaccination

Cerebral venous thrombosis is a rare illness, it compromises 0.5% of cases of cerebrovascular diseases globally. The condition can be treated if discovered and treated properly and quickly. With many known risk factors and in recent times with invent of the COVID-19 vaccine, there have been reported incidences of vaccination being implicated in cerebral venous sinus thrombosis. We report an unusual case of an adolescent female with imaging findings of deep cerebral venous sinus thrombosis and right thalamic infarction after recent vaccination against COVID-19. Laboratory results revealed microcytic hypochromic anemia. Further imaging was done which included a non-contrast CT head, magnetic resonance imaging, and magnetic resonance venography leading to a diagnosis of thrombosis of deep venous (galenic) system with vasogenic edema in bilateral thalami and left caudate nucleus with areas of infarction in the right thalamus. She was treated with subcutaneous low molecular weight heparin (Enoxaparin) and discharged on the third day under oral dabigatran and oral iron.

Imaging of Cerebral Venous Thrombosis

Cerebral venous thrombosis is a rare cause of stroke. Imaging is essential for diagnosis. Although digital subtraction angiography is still considered by many to be the gold standard, it no longer plays a significant role in the diagnosis of cerebral venous thrombosis. MRI, which allows for imaging the parenchyma, vessels and clots, and CT are the reference techniques. CT is useful in case of contraindication to MRI. After presenting the radio-anatomy for MRI, we present the different MRI and CT acquisitions, their pitfalls and their limitations in the diagnosis of cerebral venous thrombosis.

Reversible cerebral vasoconstriction syndrome: review of neuroimaging findings

Reversible cerebral vasoconstriction syndrome (RCVS) is a group of disorders characterized by segmental narrowing and dilatation of medium-to-large cerebral arteries, clinically presenting with recurrent episodes of sudden-onset thunderclap headaches, with or without focal neurological deficits. Cerebral vasoconstriction is typically reversible, with spontaneous resolution within 3 months. Although the syndrome has generally a benign course, patients with neurological deficits may experience worse outcome. The main imaging finding is segmental constriction of intracranial arteries, which can be associated with subarachnoid hemorrhage and/or ischemic foci. Other possible findings are intracranial hemorrhage, subdural bleeding and cerebral edema. The latter may have a pattern which can resemble that of posterior reversible encephalopathy syndrome, a condition that can overlap with RCVS. New imaging techniques, such as vessel wall imaging and arterial spin labeling, are proving useful in RCVS and are giving new insights into the pathophysiology of this condition. In this paper, we aim to review neuroimaging findings of RCVS.

Imaging of Headache Attributed to Vascular Disorders

Imaging is essential in the diagnosis of vascular causes of headaches. With advances in technology, there are increasing options of imaging modalities to choose from, each with its own advantages and disadvantages. This article will focus on imaging pearls and pitfalls of vascular causes of headaches. These include aneurysms, vasculitides, vascular malformations, and cerebral venous thrombosis.

Common and uncommon neuroimaging manifestations of ataxia: an illustrated guide for the trainee radiologist. Part 1 – acquired diseases

Abstract Ataxia is defined as a lack of coordination of voluntary movement, caused by a variety of factors. Ataxia can be classified by the age at onset and type (chronic or acute). The causative lesions involve the cerebellum and cerebellar connections. The correct, appropriate use of neuroimaging, particularly magnetic resonance imaging, can make the diagnosis relatively accurate and facilitate implementation of the appropriate clinical management. The purpose of this pictorial essay is to describe the imaging findings of ataxia, based on cases obtained from the archives of a tertiary care hospital, with a review of the most important findings. We also review and discuss the imaging aspects of infectious, toxic, vascular, and inflammatory diseases.

The diagnostic utility of unenhanced computed tomography of the brain and D-dimer levels in acute cerebral venous sinus thrombosis: A quantitative study

Objectives

(1) To calculate the sensitivity and specificity of the Hounsfield Unit (HU), the HU to hematocrit (H:H) ratio, and the D-dimer level in the diagnosis of acute CVST. (2) To assess the D-dimer level's linear relationship with the HU and the H:H ratio.

Materials and Methods

A single-center retrospective case-control study was conducted from 2005 to 2020. The inclusion criteria for the thrombosed and control groups were specified. A region of interest (ROI) was plotted on the respective sinuses to calculate the HU. The H:H ratio was calculated by dividing the HU value by the hematocrit value. The receiver operating characteristic curve was used to calculate the sensitivity and specificity of the HU and the H:H ratio at different cutoff values. The Pearson correlation was used to assess the linear relationship between the D-dimer level and the HU and H:H ratio.

Results

There were 19 patients in the thrombosed group and 28 patients in the control group. There were significant differences in the mean HU (71 ± 6.3 vs. 45 ± 4.8, P < 0.001) and the mean H:H ratio (2.11 ± 0.38 vs. 1.46 ± 0.63,P < 0.001). An optimal HU value of 56 yielded 100% sensitivity and specificity. An H:H value of 1.48 yielded a sensitivity of 100% and a specificity of 65%, an H:H ratio of 1.77 demonstrated a sensitivity of 85% and a specificity of 90%, and an H:H ratio of 1.88 yielded a sensitivity of 79% and a specificity of 93%. D-dimer levels had a 95% and 71% sensitivity and specificity, respectively. There was a significant moderately positive linear correlation between the D-dimer level and the HU (r = 0.52, P < 0.001) and the H:H ratio (r = 0.61, P < 0.001).

Conclusion

Unenhanced CT of the brain can be a valuable objective diagnostic tool for acute CVST diagnosis. Hounsfield blood density and its normalized ratio with hematocrit are positively correlated with D-dimer levels, which may indicate active blood coagulation in a cerebral venous sinus.

Head CT for the intensivist: 10 tips and pearls

Head imaging is an essential diagnostic tool for the management of patients with most acute neurological emergencies involving the brain. While numerous modalities including magnetic resonance imaging and catheter angiography play a role, computed tomography (CT) of the brain is far and away the most widely utilized technique because of its widespread availability and the fact that it is usually easier to implement in critically ill and potentially unstable patients. CT is particularly useful in identifying acute intracranial hemorrhage and this makes it often indispensable in the management of patients with traumatic brain injury and hemorrhagic stroke. However, shortcomings in identifying early ischemia on non-contrast CT mean that care must be taken in considering findings early after symptom onset, with newer CT sequences such as CT angiography and CT perfusion adding value. The critical role played by intensivist in managing neurocritical care patients necessitates familiarity and ability with viewing and understanding the advantages and shortcomings of head CT imaging and under which circumstances other modalities may be appropriate to obtain. This manuscript provides ten different circumstances commonly encountered in neurocritical care and how intensivists can use CT for the benefit of their patients.

Cerebral venous thrombosis: imaging patterns

Cerebral venous thrombosis (CVT) is an uncommon condition that is potentially reversible if properly diagnosed and promptly treated. Although CVT can occur at any age, it most commonly affects neonates and young adults. Clinical diagnosis is difficult because the clinical manifestations of CVT are nonspecific, including headache, seizures, decreased level of consciousness, and focal neurologic deficits. Therefore, imaging is crucial for the diagnosis. Radiologists should be able to identify the findings of CVT and to recognize potential imaging pitfalls that may lead to misdiagnosis. Thus, the appropriate treatment (anticoagulation therapy) can be started early, thereby avoiding complications and unfavorable outcomes.

Endovascular treatment for cerebral venous thrombosis: current status, challenges, and opportunities

Cerebral venous thrombosis (CVT) mostly affects young people. So far, endovascular treatment (EVT) has not been shown to be beneficial in CVT, partially because venous EVT tools are not yet fully optimized, and therefore EVT is only used as a rescue treatment in rare cases. Identifying a subgroup of CVT patients that could benefit from EVT is challenging, given the milder course of disease compared with acute ischemic stroke, the paucity of data on prognostic factors (both in the clinical and imaging domain), and the lack of consensus on what constitutes 'technical success' in CVT EVT. In this review, we discuss the major obstacles that are encountered when trying to identify CVT patients that may benefit from EVT, and propose a roadmap that could help to overcome these challenges in the near future.

Acute cerebral venous thrombosis - still an underdiagnosed pathology in emergency computed tomography of the brain

Purpose

Acute cerebral venous thrombosis (CVT) is a rare condition that can lead to a serious clinical state; thus, prompt diagnosis and treatment are mandatory. Head computed tomography (CT) plays a crucial role in the initial prompt diagnosis in the emergency setting. The aim of the study was to retrospectively analyse emergency head CT studies and the rate of incorrect diagnoses and main sources of pitfalls.

Material and methods

Retrospective analysis of 31 emergency CT studies (22 without contrast, 19F/12M, age range: 4-94 years) of patients with confirmed acute CVT.

Results

Thrombosed dural sinuses were found in 24/31 (77.4%) cases, thrombosed veins in 7/31 (22.6%) cases, no lesions within vessels in 2/31 (6.5%) cases. Haemorrhagic brain lesions were found in 9/31 (29%) cases, hypodense oedema in 6/31 (19.6%) cases, brain swelling in 1/31 (3.2%) cases, and no parenchymal lesions were revealed in 15/31 (48.4%) cases. Correct diagnosis of CVT was established in 15 cases (48.4%); however, it was incorrect in 16 cases (51.6%). Incorrect cases consist of 4 groups: 1 – with both vascular and parenchymal lesions that were overlooked (50%), 2 – with vascular lesions only, which were either overlooked, misinterpreted, or covered by artefacts (31.3%,), 3 – with parenchymal lesions only, which were misinterpreted (12.5%), and 4 – with no lesions present in the emergency head CT (6.2%).

Conclusions

The high rate of incorrect diagnoses of acute CVT based on emergency head CT requires constant training of radiologists and their close cooperation with clinicians because a delayed diagnosis may be lethal to the patient.

Central Nervous System Injury in Patients With Severe Acute Respiratory Syndrome Coronavirus 2: MRI Findings

Due to the presence of a new and rapidly spreading coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the World Health Organization declared the coronavirus disease 2019 (COVID-19) outbreak a pandemic on March 11, 2020. This new disease has a multisystemic effect that predominantly targets the respiratory system; however, neurologic symptoms have been documented in approximately 36% of patients with confirmed COVID-19. During the period of March 2020 to March 2021, 481 brain MRI studies were performed by medical request. Of these, 9.7% (n = 47) were hospitalized with a diagnosis of COVID-19 pneumonia confirmed by SARS-CoV-2 reverse transcriptase-polymerase chain reaction (RT-PCR) test with the following findings: microbleeds, osmotic demyelination, arterial thrombosis, ischemic infarcts, venous thrombosis, metabolic cerebellar syndrome, posterior reversible leukoencephalopathy, abnormal signal intensity in the frontal lobes and olfactory bulbs, microangiopathy, gliosis, and findings consistent with hypoxic-ischemic encephalopathy. In patients with histories of malignant central nervous system (CNS) tumors, the most frequent histological lineage being high-grade glioma, 100% progression was identified with respect to previous imaging studies, without other significant findings. In two patients, a brain MRI was performed due to altered alertness, identifying only involutive changes in the brain parenchyma; MRI was repeated 72 hours later, after a lack of improvement in higher functions, without identifying imaging findings. To date, limited studies have documented CNS abnormalities related to COVID-19 using MRI. Therefore, the purpose of this study is to present abnormal imaging findings in patients with SARS-CoV-2 infection and their clinical correlations.

Isolated cortical vein thrombosis in a young male adult

Isolated cortical vein thrombosis (ICVT) is a rare entity and accounts for only 6.3% of cerebral venous and sinus thrombosis. ICVT is an uncommon cause of seizures in young adults. We present a 27-year-old man with no medical history who presented with dizziness, loss of consciousness and a seizure-like episode. The patient was found to have an elevated D-dimer and brain imaging revealed ICVT. The patient was started on anticoagulation and antiseizure medications. A high index of suspicion for uncommon aetiologies for new-onset seizure, especially in the young, is key to accurate diagnosis of ICVT. Evaluation and work-up should include detailed physical examination, along with appropriate brain imaging and testing for other conditions that predispose venous thrombosis. In the setting of the SARS-CoV-2 pandemic, testing for COVID-19 may also be warranted. Rapid diagnosis and full anticoagulation can help avoid debilitating complications and long-term sequelae.

Imaging of intracranial fat: from normal findings to pathology

The presence of intracranial adipose tissue is often overlooked, although it may be detected in different physiological (dural sinuses or falx deposition of fat) and pathological (lipoma, dermoid cyst, subarachnoid fat dissemination) conditions. In this review, we illustrate various scenarios in which radiologists and neuroradiologists may encounter intracranial fat, providing a list of differential diagnosis.

Non-contrast magnetic resonance venography with Inhance 3D Velocity: diagnostic performance for intracranial venous thrombosis

PURPOSE

The aim of this study was to evaluate the diagnostic performance of Inhance 3D Velocity (I3DV) in intracranial venous thrombosis and investigate the possible impact of venous sinus hypoplasia/aplasia on false thrombosis diagnosis made with I3DV.

METHODS

This study included 540 patients. Contrast-enhanced magnetic resonance venography combined with conventional sequences was considered the gold standard test (GST), while I3DV was considered as diagnostic test. We accessed the diagnostic success of I3DV for intracranial venous thrombosis detection, thrombosed vessel identification, and total/partial thrombus distinction. The possible relationship between false-positive thrombus diagnosed by I3DV and venous sinus hypoplasia or aplasia diagnosed by GST was investigated.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of I3DV in the detection of intracranial venous thrombosis were 95.7%, 92.1%, 64.1%, 99.3%, and 92.6%, respectively. A significant association was observed between I3DV and GST in terms of thrombosis detection and total/partial thrombus distinction (p < 0.001). A significant relationship was observed between false-positive thrombosis diagnosis in I3DV and hypoplasia in the left transverse sinus (p < 0.001).

CONCLUSION

Intracranial venous thrombosis may be diagnosed faster and more accurately than traditional phase contrast magnetic resonance angiography in I3DV. This technique can be used in situations where contrast medium application is contraindicated. As in other non-contrast magnetic resonance venography techniques, left transverse sinus hypoplasia can be diagnosed as a thrombosed vessel in I3DV.

Dural venous sinus tumour thrombus from metastatic thymoma

Thymomas are the most common primary tumours of the anterior mediastinum. While intrathoracic disease progression through local invasion is well described in the literature, extrathoracic extension of disease is uncommon and intracranial metastases have seldom been reported. We present a case of extensive dural venous sinus tumour thrombus in a patient with metastatic invasive thymoma.

Cerebral venous thrombosis: Diagnosis and management in the emergency department setting

INTRODUCTION

Cerebral venous thrombosis (CVT) is an uncommon neurologic emergency associated with significant morbidity and mortality that can be difficult to differentiate from other conditions. It is important for the emergency clinician to be familiar with this disease as it requires a high index of suspicion, and early diagnosis and management can lead to improved outcomes.

OBJECTIVE

This narrative review provides an evidence-based update concerning the presentation, evaluation, and management of CVT for the emergency clinician.

DISCUSSION

CVT is due to thrombosis of the cerebral veins resulting in obstruction of venous outflow and increased intracranial pressure. Early recognition is important but difficult as the clinical presentation can mimic more common disease patterns. The most common patient population affected includes women under the age of 50. Risk factors for CVT include pregnancy, medications (oral contraceptives), inherited thrombophilia, prior venous thromboembolic event, malignancy, recent infection, and neurosurgery. CVT can present in a variety of ways, but the most common symptom is headache, followed by focal neurologic deficit, seizure, and altered mental status. Imaging studies such as computed tomography (CT) venography or magnetic resonance (MR) venography should be obtained in patients with concern for CVT, as non-contrast CT will be normal or have non-specific findings in most patients. Treatment includes anticoagulation, treating seizures and elevated ICP aggressively, and neurosurgical or interventional radiology consultation in select cases.

CONCLUSIONS

CVT can be a challenging diagnosis. Knowledge of the risk factors, patient presentation, evaluation, and management can assist emergency clinicians.

Pearls and Pitfalls in the Magnetic Resonance Diagnosis of Dural Sinus Thrombosis: A Comprehensive Guide for the Trainee Radiologist

Dural sinus thrombosis (DST) is a potentially fatal neurological condition that can be reversed with early diagnosis and prompt treatment. Non-enhanced CT scan is often the first imaging investigation in patients presenting with acute neurological symptoms; however, its poor sensitivity in detecting DST is a major drawback. Magnetic resonance (MR) imaging offers multiple advantages such as excellent contrast resolution and unenhanced venography possibilities, making it the mainstay in the non-invasive diagnosis of DST. However, physiological variations, evolution of thrombi, and incorrect selection/application of MR techniques can lead to false positive and false negative interpretations impacting patient management and outcome. This article discusses the MR techniques useful to diagnose DST and describes pitfalls, with troubleshooting methods, to ensure an accurate diagnosis. We have used multiple diagrammatic illustrations and MR images to highlight pertinent take-home points and to serve as an easy guide for day-to-day clinical practice.

Acute subdural haemorrhage complicating cerebral venous thrombosis in a patient with protein C deficiency

Cerebral venous thrombosis (CVT) directly causing subdural haemorrhage (SDH) is a rare entity. We present a case of an 18-year-old female patient who presented with severe occipital headache. Neuroimaging showed acute SDH and CVT. She was eventually discovered to have underlying protein C deficiency. She was treated with anticoagulation and made an uneventful recovery. We aim to highlight the epidemiology, risk factors and aetiopathogenesis of CVT. We have included a literature review of previously described 13 case studies/reports describing SDH associated with CVT and a brief discussion of the dilemmas associated with management.

Management and outcomes of newborns at risk for inherited antithrombin deficiency

BACKGROUND

As levels of antithrombin (AT) are low at birth, diagnosing inherited AT deficiency in newborns is challenging. In Stockholm, Sweden, pregnant women with known AT deficiency are referred to the Karolinska University Hospital, where local guidelines for management of newborns at risk of inherited AT deficiency have been established. Data on pregnancy, obstetric, and neonatal outcomes are recorded in a registry.

OBJECTIVES

We aimed to evaluate the current practice at the Karolinska University Hospital for managing delivery of newborns at risk for AT deficiency, the predictive value of AT levels at birth, and the neonatal outcomes of newborns with AT deficiency.

PATIENTS/METHODS

This was an observational, retrospective study. All children born to mothers with AT deficiency at the Karolinska University Hospital 2003-2018 were identified from the registry and included in the study. Data were collected from the medical records and the registry. AT activity was measured postnatally and after 6 months of age.

RESULTS

The total study cohort included 41 newborns. There was a significant association between low AT values postnatally and after 6 months of age (P = .001). Half (21/41) of the children were diagnosed with AT deficiency; two suffered from sinus thrombosis, which presented at 10 days of age. Both children with sinus thrombosis were delivered using vacuum extraction.

CONCLUSIONS

The current practice of testing newborns can in most cases predict inherited AT deficiency. The risk for thrombosis during the neonatal period is enhanced by the use of instrumental delivery.

Cerebral Venous Thrombosis: Review of Diagnosis, Follow-Up, Late Complications and Potential Pitfalls

Cerebral venous thrombosis is a less common but relevant cause of stroke in adults. The clinical manifestations are nonspecific leading frequently diagnostic delays, so imaging findings are is of vital importance. Conventional imaging modalities, namely computed tomography and magnetic resonance imaging (MRI), allow identification of the thrombus and parenchymal involvement due to venous congestion to a variable degree, but this entity may appears as a nonexpected finding in a nonvenographic study. computed tomography and MRI venographies allow noninvasive confirmation of the diagnosis and adequate characterization of the extent of the thrombus and acute complications, both of them being robust diagnostic techniques. MR venography also can be done without the use of contrast media, which is especially important in certain clinical situations. Cerebral venous thrombosis needs follow-up, and imaging plays a key role in detection of late complications of the disease, including dural arteriovenous fistulas and intracranial hypertension due to veno-occlusive disease. Knowledge of other diseases and conditions that may mimic a thrombus is needed to avoid wrong diagnosis. In this article, we conduct a pictorial comprehensive review of cerebral venous thrombosis, including also the technical aspects of different imaging modalities, diagnosis and acute complications, follow-up, late complications and potential imaging mimics.