Automated evaluation of collateral circulation for outcome prediction in acute ischemic stroke

INTRODUCTION

The assessment of collateral circulation in acute ischemic stroke management is essential. Modern tools, such as Brainomix's e-CTA, powered by artificial intelligence, provide detailed insights into collateral assessment. This retrospective study aims to identify factors contributing to favorable collateral status and compare outcomes between patients with good collaterals (grade 3) and fair collaterals (grade 0-2).

METHOD

This retrospective study included 97 patients admitted to the Stroke Unit at the Hospital de Clínicas of the Federal University of Paraná, Brazil, from September 2021 to January 2023. Comparative analyses involved demographic factors, cardiovascular risk factors, and the combined outcome of mortality and moderate to severe disability at discharge, 30-day, and 90-day follow-ups.

RESULTS

Among the 97 cases, 58.8 % showed 'good collaterals' with a grade 3 status. Variables affecting collateral status included age (p = 0.042), neutrophil-lymphocyte ratio (p = 0.005), and initial NIHSS scores (p<0.001). The presence of good collaterals according to e-CTA reduced the odds of death and moderate-severe disability at discharge (p = 0.003; OR 0.27) and at 30 days (p = 0.015; OR 0.33), although this effect diminished at the 90-day mark after multivariate analysis.

DISCUSSION

Automated collateral assessment through e-CTA is a valuable tool in acute ischemic stroke evaluation. Good e-CTA collateral score serve as a promising imaging biomarker, guiding informed clinical decisions during Stroke Unit hospitalizations. This study highlights the relationship between collaterals and stroke outcomes and underscores the potential for AI-driven tools to enhance stroke care management.

Retrosigmoid Craniotomy and Intradural Variations: Role of Patient-specific Preoperative Imaging to Identify Landmarks and Relevant Structures

OBJECTIVE

There are several landmarks to safely identify the limits of the retrosigmoid approach and its intradural variations, however, little has been discussed about how those landmarks may vary among patients.

METHOD

We provided a review of patient positions, surface landmarks for the retrosigmoid craniotomy, and structures to recognize for transmeatal, suprameatal, suprajugular and transtentorial extensions.

RESULTS

The position of the dural sinuses in relation with the zygomatic-inion line, and digastric notch line is readily identified on MRI. For transmeatal drilling, the position of the semicircular canals, vestibular aqueduct and jugular bulb is best evaluated on CT. For suprameatal drilling, the labyrinth and the position and integrity of the carotid canal are relevant to plan the anterior extension of the approach. For transtentorial extension, it is desirable to identify incisural structures. For suprajugular drilling, the position of the jugular bulb, invasion of venous structures, and integrity of the roof of the jugular foramen must be checked preoperatively.

CONCLUSION

The retrosigmoid approach is the workhorse of posterior skull base surgery. By recognizing patient-specific variations in known landmarks, the approach may be tailored prevent complications.

Carotid artery aneurysm and hypomelanosis of Ito

INTRODUCTION

Hypomelanosis of Ito is a rare neurocutaneous syndrome characterized by hypopigmented skin lesions, abnormalities of the central nervous system, skeletal system, eyes and teeth.

CASE PRESENTATION

We present a case of a 4-year-old boy with hypomelanosis of Ito and neck pulsatile mass due to a giant left common carotid dissecting aneurysm.

DISCUSSION

To our knowledge, this is the first report of association of hypomelanosis of Ito with carotid aneurysm.

CONCLUSION

For children with hypomelanosis of Ito and abnormal neurologic findings, vascular neuroimaging should be considered.

Prevertebral Inflammatory Myofibroblastic Tumor Following COVID Vaccine Booster Dose

We report a case of a 30-year-old previously higid female presenting with dorsal pain and persistent fever after COVID-19 vaccine booster dose. CT and MR revealed a prevertebral heterogeneous and infiltrating mass, with spontaneous regression in control imaging which biopsy confirmed an inflammatory myofibroblastic tumor.

Perfusion-weighted imaging in vestibular schwannoma: the influence that cystic status and tumor size have on perfusion profiles

Objective

The perfusion profile of vestibular schwannomas (VSs) and the factors that influence it have yet to be determined.

Materials and Methods

Twenty patients with sporadic VS were analyzed by calculating parameters related to the extravascular extracellular space (EES)-the volume transfer constant between a vessel and the EES (Ktrans); the EES volume per unit of tissue volume (Ve); and the rate transfer constant between EES and blood plasma (Kep)-as well as the relative cerebral blood volume (rCBV), and by correlating those parameters with the size of the tumor and its structure (solid, cystic, or heterogeneous).

Results

Although Ktrans, Ve, and Kep were measurable in all tumors, rCBV was measurable only in large tumors. We detected a positive correlation between Ktrans and rCBV (r = 0.62, p = 0.031), a negative correlation between Ve and Kep (r = -0.51, p = 0.021), and a positive correlation between Ktrans and Ve only in solid VSs (r = 0.64, p = 0.048). Comparing the means for small and large VSs, we found that the former showed lower Ktrans (0.13 vs. 0.029, p < 0.001), higher Kep (0.68 vs. 0.46, p = 0.037), and lower Ve (0.45 vs. 0.83, p < 0.001). The mean Ktrans was lower in the cystic portions of cystic VSs than in their solid portions (0.14 vs. 0.32, p < 0.001), as was the mean Ve (0.37 vs. 0.78, p < 0.001). There were positive correlations between the solid and cystic portions for Ktrans (r = 0.71, p = 0.048) and Kep (r = 0.74, p = 0.037).

Conclusion

In VS, tumor size appears to be consistently associated with perfusion values. In cystic VS, the cystic portions seem to have lower Ktrans and Ve than do the solid portions.

Incomplete hippocampal inversion: diagnostic criteria and effect on epilepsy, seizure localization and therapeutic outcome in children

PURPOSE

Elaborate a simple Magnetic Resonance Imaging (MRI)-based score to define Incomplete Hippocampal Inversion (IHI) in children (Phase 1), and evaluate the relation of IHI with (A) epilepsy, (B) seizure localization and (C) therapeutic response in a paediatric population (Phase 2).

METHODS

In Phase 1, incompletely inverted hippocampi were matched to completely inverted hippocampi. Multiple qualitative and quantitative hippocampal and extra-hippocampal features were evaluated in coronal-oblique T1-weighted (T1W) and coronal T2-weighted (T2W) images. Multivariate analysis was performed to elaborate the MRI-based score to define IHI. In Phase 2, epilepsy patients were matched to controls, and the T1W and T2W scores were applied. Multivariate analysis was performed to assess the relation of IHI and epilepsy, seizure localization and therapeutic response.

RESULTS

The hippocampal diameter ratio and parahippocampal angle in the coronal-oblique T1-weighted images, and the hippocampal diameter ratio and collateral sulcus depth in the coronal T2-weighted images predicted IHI in Phase 1. Simple and practical imaging-based scores were developed and are available on the website: https://ihiscore.netlify.app/. The Area Under the Receiver Operating Characteristic Curve of the T1W and T2W scores were, respectively, 0.965 and 0.983. In Phase 2, IHI independently predicted epilepsy (OR = 3.144, 95% CI = 1.981-4.991, p < 0.001), temporal lobe epilepsy (OR = 4.237, 95% CI = 1.586-11.318, p = 0.004), and drug resistant epilepsy (OR = 7.000, 95% CI = 2.800-17.500, p < 0.001).

CONCLUSION

The association between IHI and temporal lobe epilepsy (and the lack of association with extra-temporal epilepsy) favours the possibility of a relation between IHI and the pathophysiology of seizures in epileptic patients. Furthermore, IHI is a potential prognostic marker for therapeutic response in epilepsy.

Relationship between Signal Intensity of the Labyrinth and Cochleovestibular Testing and Morphologic Features of Vestibular Schwannoma

Objectives The aim of this article was to evaluate the relationship between signal intensity of the labyrinth and vestibulocochlear function and morphologic features of vestibular schwannoma (VS).

Design Cross-sectional Study.

Setting Tertiary referral center.

Participants Fifty-four patients with sporadic, untreated VS.

Main Outcome Measure Signal intensity of the cochlea and vestibule (SIRc and SIRv: signal intensity of cochlea/vestibule compared with cerebellar signal intensity; AURc and AURv: SIRc/SIRv of the affected side compared with the unaffected side) in 1.5T T2-weighted images was correlated with size (Hannover classification), cystic status, distance from the fundus of the internal auditory canal, video head impulse test (vHIT), and audiometry.

Results Signal intensity of the vestibule was higher than that of the cochlea (p < 0.01). Large tumors had lower SIRc than smaller tumors (p = 0.03); Hannover T1 tumors had higher SIRc (p < 0.01), SIRv (p < 0.01), AURc (p < 0.01) and AURv (p < 0.01) than the rest; heterogenous and cystic tumors had higher SIRv than solid large tumors (p = 0.02); superior vestibular nerve pattern on vHIT had higher SIRv and AURv than inferior vestibular nerve and mixed patterns (p = 0.03 and 0.004, respectively); and there was a weak correlation between AURv and speech discrimination (r = 0.33, p = 0.04).

Conclusion A more abnormal signal intensity of the labyrinth is associated with larger size and solid status of VS. There was a positive relationship between signal intensity of the labyrinth and speech discrimination scores on audiogram.

From the inside out: oculocerebrocutaneous syndrome without dermatological manifestations

Delleman-Oorthuys or oculocerebrocutaneous syndrome (OCCS) is an extremely rare condition which relies on three pillars of manifestations: ophthalmological, neurological, and dermatological. It was first described by Delleman and Oorthuys in 1981, and since then, very few other cases have been reported. We report the case of a 13-month-old boy, referred to an ophthalmological tertiary service for investigation of a microglobe with a cystic retrobulbar mass on translucency test. MRI revealed a left microphthalmia, with extensive retrobulbar cystic lesions occupying the remaining orbit and protruding anteriorly the microglobe. Cerebral findings included polymicrogyria, subependymal nodular heterotopia at the level of the left occipital horn of the lateral ventricle, and an importantly enlarged mesencephalic tectum observed in association with an absent cerebellar vermis. The ensemble of malformations met the criteria for definite OCCS. Being a tremendously rare syndrome, OCCS will always represent a diagnostic challenge. However, its emblematic cutaneous manifestations might be an important part of the road map leading to its correct interpretation. Thus, when absent, diagnosis can be harder than usual, and, on these cases, neurologists, ophthalmologists, and radiologists play a crucial role.

Brainstem hyperintensity in patients with vestibular schwannoma is associated with labyrinth signal on magnetic resonance imaging but not vestibulocochlear tests

OBJECTIVES

Focal hyperintensity in the dorsal brainstem (HDB) has been described in large cerebellopontine angle tumours and is thought to represent vestibular nuclei degeneration, but its functional significance has not been thoroughly investigated. Our aim was to analyse its relationship to imaging characteristics of the tumour and inner-ear structures and to vestibulocochlear functional tests.

METHODS

We retrospectively reviewed 54 patients with a histological diagnosis of vestibular schwannoma (VS). Magnetic resonance imaging tumour characteristics (size, cystic composition and distance from the cochlear aperture), signal intensity ratio of the cochlea and vestibule in fluid-attenuated inversion recovery (FLAIR) and fast imaging employing steady-state acquisition (FIESTA)/fast spin-echo imaging with variable flip angles (CUBE) and vestibulocochlear function tests (audiometry, auditory brainstem response (ABR) and video head impulse testing (vHIT)) were obtained. Statistical analyses were performed to evaluate their relation to focal HDB.

RESULTS

Focal HDB was found in 22% of VS. It was significantly associated with large (p < 0.001) and cystic (p = 0.004) tumours and also with tumours located further from the cochlear aperture (p = 0.039). The signal intensity ratio of the cochlea on FLAIR was higher in patients with HDB (p < 0.014), but this difference was not observed in FIESTA/CUBE (p = 0.981). Audiometry, ABR and vHIT results did not significantly differ in patients with HDB, but ABR results were worse in patients with higher cochlear signal intensity on FLAIR sequences (p = 0.026).

CONCLUSIONS

Focal HDB in patients with VS was associated with increased signal intensity ratio of the cochlea on FLAIR in patients with VS but not directly to the results of vestibulocochlear function tests.

Carotid-Esophageal Fistula Treated By Endovascular Approach

The carotid-esophageal fistula is a rare and serious complication of the metallic esophageal prosthesis. A high index of suspicion is required for early diagnosis and treatment, decreasing the morbidity and mortality rate of this severe complication. We report a case of a 4-year-old boy presenting severe upper gastrointestinal bleeding due to a carotid-esophageal fistula, secondary to deployment of an esophageal metallic prosthesis for treatment of a recurrent stenosis. The carotid pseudo-aneurism was successfully treated with stents and coils. Although endovascular treatment is a safe and effective option, arterial stenting in children needs further studies with long-term follow-up.

Image Fusion in Neurovascular Compression Syndrome Related to Hemifacial Spasm

Neurovascular compression syndromes have well characterized clinical symptoms, but precise identification of the pathologic contact between the nerves and vessels can be challenging at neuroimaging. Considering that neurovascular contacts are frequent imaging findings in asymptomatic patients, correct visualization of pathological contact is crucial for the diagnosis and surgical planning. We have used magnetic resonance imaging fusion by overlaying color-coded T1-weighted postcontrast onto high-resolution T2-weighted images to better delineate imaging findings by enhancing vascular structures.

Turbulent Cerebrospinal Fluid Flow in Enlarging Terminal Myelocystocele

Terminal myelocystocele is a rare type of neural tube malformation, consisting of a skin-covered lumbosacral mass, highly associated with other complex abdominal malformations within the OIES complex (omphalocele, imperforate anus, exstrophy of the cloaca and spinal defects). We present a case of a premature female with an extensive lumbosacral mass at birth, as well as an omphalocele, cloacal exstrophy, renal abnormalities, and sacral agenesis. Lumbar magnetic resonance imaging revealed a meningocele sac herniating through the bone defects and containing a syringocele sac. Advanced imaging techniques showed turbulent cerebrospinal fluid flow. At control, 4 weeks later, the defect doubled in size. The myelocystocele sac was evacuated and closed, and the patient persisted with paraparesis. The role of cerebrospinal fluid flow analysis is well established in Chiari-type malformations, in which turbulent flow within the syrinx is related to a better outcome after surgery. It is possible that the same principle could be applied to other spinal malformations, as shown in this case of terminal myelocystocele.

Matas test revisited: carotid compression for embolization of high-flow pediatric pial arteriovenous fistulas

OBJECTIVE

Cerebral pial arteriovenous fistula (AVF) is a rare vascular malformation and may cause hemorrhage and neurological deficit. The presence of high-flow shunts constitutes a challenge when performing the endovascular technique, due to risk of distal embolization. The authors report a simple maneuver, adapted from the Matas test, that was successfully applied to treat a child with two pial AVFs.

METHODS

An 8-year-old boy presented with headache and vomiting due to two single-channel high-flow intracerebral pial AVFs. He was treated with an endovascular approach using brief, gentle compression of the ipsilateral cervical carotid artery. The temporary flow arrest ensured proper placement of the first coil, allowing definitive obliteration of the shunt.

RESULTS

There were no complications with the procedure, and the patient recovered uneventfully. Throughout the 9-month follow-up, the patient experienced a stable neurological condition, with both fistulas occluded and improvement of local circulation.

CONCLUSIONS

This easy-to-perform maneuver allows precise positioning of embolic material into high-flow shunts to facilitate treatment of pial AVF.

The use of e-ASPECTS in acute stroke care: validation of method performance compared to the performance of specialists

BACKGROUND

The rapid evaluation of non-contrast-enhanced computed tomography (NCCT) brain scans in patients with anterior stroke symptoms saves time and favors optimal and prompt treatment. e-ASPECTS is a tool that automatically calculates the Alberta Stroke Program Early CT Score (ASPECTS) values, leading to a more accurate and timely image evaluation.

OBJECTIVE

To determine the ability of e-ASPECTS in differentiating images with and without injury.

METHODS

One-hundred sixteen patients admitted to a stroke unit in a Brazilian tertiary hospital underwent a CT scan at admission and at least one control brain imaging (NCCT or magnetic resonance imaging - MRI) 24 hours after admission. ASPECTS evaluation was performed by three neuroradiologists, three neurologists, and three neurology residents, all blinded to the symptoms and the injury side. The scores were compared to the ground truth, and an ASPECTS score was provided by two independent non blinded evaluators. Sensitivity and specificity were analyzed, and receiver operating characteristic curves, Bland-Altman plots with mean error score, and Matthews correlation coefficients (MCCs) were obtained for ASPECTS scores, assuming values equal to 10 for images without injury and values other than 10 for images with ischemic injury.

RESULTS

e-ASPECTS demonstrated similar performance to that of neuroradiologists and neurologists, with an area under the curve of 0.78 and an MCC value of 0.48 in the dichotomous analysis. The sensitivity and specificity of e-ASPECTS were 75% and 73%, respectively.

CONCLUSION

e-ASPECTS is a validated and reliable tool for determining early signs of ischemia in NCCT.

Video Head Impulse Test to Preoperatively Identify the Nerve of Origin of Vestibular Schwannomas

BACKGROUND

Identification of the nerve of origin in vestibular schwannoma (VS) is an important prognostic factor for hearing preservation surgery. Thus far, vestibular functional tests and magnetic resonance imaging have not yielded reliable results to preoperatively evaluate this information. The development of the video head impulse test (vHIT) has allowed a precise evaluation of each semicircular canal, and its localizing value has been tested for some peripheral vestibular diseases, but not for VS.

OBJECTIVE

To correlate patterns of semicircular canal alteration on vHIT to intraoperative identification of the nerve of origin of VSs.

METHODS

A total 31 patients with sporadic VSs were preoperatively evaluated with vHIT (gain of vestibule-ocular reflex, overt and covert saccades on each semicircular canal) and then the nerve of origin was surgically identified during surgical resection via retrosigmoid approach. vHIT results were classified as normal, isolated superior vestibular nerve (SVN) pattern, isolated inferior vestibular nerve (IVN) pattern, predominant SVN pattern, and predominant IVN pattern. Hannover classification, cystic component, and distance between the tumor and the end of the internal auditory canal were also considered for analysis.

RESULTS

Three patients had a normal vHIT, 12 had an isolated SVN pattern, 5 had an isolated IVN pattern, 7 had a predominant SVN pattern, and 4 had a predominant IVN pattern. vHIT was able to correctly identify the nerve of origin in 89.7% of cases (100% of altered exams).

CONCLUSION

The pattern of semicircular canal dysfunction on vHIT has a localizing value to identify the nerve of origin in VSs.

Video Head Impulse Test in Vestibular Schwannoma: Relevance of Size and Cystic Component on Vestibular Impairment

OBJECTIVES

Tumor factors that influence vestibular function in vestibular schwannoma (VS) have not been properly described. We evaluated whether cystic VSs have different vestibular function than solid VS. Tumor size on vestibular function was also evaluated.

STUDY DESIGN

Cross-sectional study.

SETTING

Tertiary referral center.

PATIENTS

Forty-one cases of sporadic, untreated VS.

INTERVENTION

Evaluation with video head impulse test and MRI.

MAIN OUTCOME MEASURES

Tumors were classified as solid, heterogeneous, or cystic and by size using the Hannover classification. Vestibulo-ocular reflex (VOR) gain was correlated to tumor size and cystic status.

RESULTS

Large VS had worse VOR gain than small lesions (p < 0.001). Cystic lesions had lower VOR gain than all other tumors (p = 0.001), Hannover T3 and T4 (p = 0.014), Hannover T4 (p = 0.015), solid tumors (p < 0.001), solid Hannover T3 and T4 (p = 0.003), and solid Hannover T4 (p = 0.008). Heterogeneous VSs had lower VOR gain compared to solid tumors (p = 0.02), solid Hannover T3 and T4 (p = 0.08), and solid Hannover T4 (p = 0.14). Heterogeneous and cystic VSs had lower VOR gain than solid tumors (p < 0.001), solid Hannover T3 and T4 (p = 0.004), and solid Hannover T4 (p = 0.02). VOR gain of solid T4 lesions was not significantly lower than solid Hannover T1-T3 (p = 0.33).

CONCLUSION

Cystic status is directly associated with a worse vestibular dysfunction. Size did not significantly impact vestibular function in solid VS.

Cerebellopontine angle schwannomas arising from the intermediate nerve: a scoping review

Intermediate nerve schwannomas (INS) are extremely rare lesions in literature. They have been described mimicking facial nerve schwannomas, but not vestibular schwannomas (VS). We aimed to review the previously published cases, as well as the evidence to believe that they are far more common, though usually misdiagnosed as facial or VS. We performed a review of PubMed/Medline and Embase of "intermediate nerve schwannoma," "facial nerve schwannoma," "greater superficial petrosal nerve schwannoma," "geniculate ganglion schwannoma," and "chorda tympani schwannoma" to identify all cases of INS, following the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) statement. Furthermore, 2 cases operated at our center are shown to exemplify the proposed hypotheses. No article was excluded from review. Thirteen cases of INS, 11 cases of chorda tympani schwannoma, and 18 cases of greater superficial petrosal nerve schwannoma were found in literature. In facial nerve schwannomas, the predilection of schwannomas for sensory nerves, and the ability to preserve the motor facial nerve during tumor resection support the hypothesis of intermediate nerve as the nerve of origin. For VSs, the different arachnoidal arrangement of medial VS, the sharing of pia mater by the intermediate nerve and vestibular nerve, and the medial Obersteiner-Redlich zone of the intermediate nerve, support the hypothesis of intermediate nerve origin of some VS. The correct identification of the intermediate nerve as a nerve of origin of cerebellopontine angle schwannomas is of uttermost importance, especially when mistaken for VS, as this may account for the heterogeneity of facial and cochlear outcomes after surgery.

ACOUSTIC RADIATION FORCE IMPULSE IS EQUIVALENT TO LIVER BIOPSY TO EVALUATE LIVER FIBROSIS IN PATIENTS WITH CHRONIC HEPATITIS C AND NONALCOHOLIC FATTY LIVER DISEASE

BACKGROUND

Liver biopsy is recommended as the gold standard method for assessing the stage of liver fibrosis in patients with chronic liver disease. However, it is invasive, with potential risks and complications. Elastography is an ultrasound technique that provides information of changes in the liver tissue, evaluating tissue elasticity and acoustic radiation force impulse is one of the available techniques.

OBJECTIVE

The main objective of this study was to evaluate the sensitivity and specificity of acoustic radiation force impulse comparing to liver biopsy to evaluate fibrosis in patients with chronic hepatitis C virus and nonalcoholic fatty liver disease.

METHODS

Twenty four patients were included, everyone underwent liver biopsy and acoustic radiation force impulse, and the results were compared with values described in the literature by several authors.

RESULTS

In the population of patients with chronic hepatitis C, our data were better correlated with data published by Carmen Fierbinteanu-Braticevici et al., with an accuracy of 82.4%, sensitivity of 71.4% and specificity of 90%. For nonalcoholic fatty liver disease, our data were better correlated with data published by Masato Yoneda et al., with an accuracy of 85.7%, sensitivity 80% and specificity of 100%.

CONCLUSION

Acoustic radiation force impulse is a method with good accuracy to distinguish initial fibrosis from advanced fibrosis in hepatitis C virus and nonalcoholic fatty liver disease and can replace biopsy in most cases.