Large vessel occlusion detection by non-contrast CT using artificial ıntelligence

INTRODUCTION

Computer vision models have been used to diagnose some disorders using computer tomography (CT) and magnetic resonance (MR) images. In this work, our objective is to detect large and small brain vessel occlusion using a deep feature engineering model in acute of ischemic stroke.

METHODS

We use our dataset. which contains 324 patient's CT images with two classes; these classes are large and small brain vessel occlusion. We divided the collected image into horizontal and vertical patches. Then, pretrained AlexNet was utilized to extract deep features. Here, fc6 and fc7 (sixth and seventh fully connected layers) layers have been used to extract deep features from the created patches. The generated features from patches have been concatenated/merged to generate the final feature vector. In order to select the best combination from the generated final feature vector, an iterative selector (iterative neighborhood component analysis-INCA) has been used, and this selector has chosen 43 features. These 43 features have been used for classification. In the last phase, we used a kNN classifier with tenfold cross-validation.

RESULTS

By using 43 features and a kNN classifier, our AlexNet-based deep feature engineering model surprisingly attained 100% classification accuracy.

CONCLUSION

The obtained perfect classification performance clearly demonstrated that our proposal could separate large and small brain vessel occlusion detection in non-contrast CT images. In this aspect, this model can assist neurology experts with the early recanalization chance.

Arterial blood gas analysis predicts futile recanalization in mechanical thrombectomy-treated acute ischemic stroke patients: a multicenter study

OBJECTIVE: It is known that providing recanalization alone in large vessel occlusions is not sufficient to provide a good 90-day clinical outcome. It is advocated that neuroprotection should be increased before endovascular treatment and that the penumbra should be protected from reperfusion damage after recanalization. However, the effects of blood gas parameters before and after mechanical thrombectomy on clinical outcomes are not clear. The objective of this study is to assess the effectiveness of serial blood gas measures in accurately predicting futile recanalization at an early stage. PATIENTS AND METHODS: This study is a multicenter inquiry that collected data in a prospective manner and analyzed it retrospectively. Patients with a 2b-3 thrombolysis in cerebral infarction (TICI) score after mechanical thrombectomy for recanalization were consecutively analyzed from July 2022 to March 2023. Arterial blood gas parameters, including pH, oxygen saturation (SaO2), partial carbon dioxide pressure (PaCO2), partial oxygen pressure (PaO2), lactate, and bicarbonate (HCO3), were measured at four time points: before mechanical thrombectomy treatment (preoperative), immediately after recanalization (postoperative 1st), during the 3rd hour (postoperative 3rd), and at the 5th hour (postoperative 5th). The patients were categorized into groups based on their modified Rankin Scale (mRS) scores. RESULTS: The study included 136 patients with an average age of 69.71±11.22. The postoperative 1st-hour SaO2 values were lower in the mRS 3-6 group (p=0.038). The postoperative pH and lactate mean were greater in the mRS 3-6 group than in the 0-2 group (p=0.038 and 0.018, respectively). In logistic regression, a unit rise in lactate increased poor functional outcomes 1,632 times (p=0.024). Early neurological recovery was associated with decreased postoperative 3rd-hour lactate (p=0.014). The mean postoperative PaO2 (average of 1, 2, 3 PaO2) was higher in those with symptomatic cerebral bleeding (p=0.044). CONCLUSIONS: Monitoring lactate and pH levels in AIS patients who have had mechanical recanalization can be utilized to predict mortality and morbidity, especially in the first five hours after the procedure.

Graphical Abstract

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Do novel oral anticoagulant drugs used in patients with nonvalvular atrial fibrillation act only as anticoagulants?

OBJECTIVE

Although inflammation has an important role in the pathogenesis of atrial fibrillation (AF), the effect of novel oral anticoagulants (NOAC) used to reduce the risk of ischemic stroke and embolism on inflammation remains unknown. In this study, we aimed to investigate the effects of NOAC, which have been shown to have anticoagulant properties, on inflammation and platelet reactivation, which have an important role in the pathogenesis of AF.

PATIENTS AND METHODS

A total of 530 patients, including 380 patients with nonvalvular AF using NOAC and 150 patients with nonvalvular AF who did not use any NOAC were included in the study. Neutrophil-to-lymphocyte ratio (NLR) was calculated as the ratio of absolute neutrophil count to absolute lymphocyte count. Mean platelet volume (MPV), red cell distribution width (RDW), and neutrophil-to-lymphocyte ratio (NLR) values of both groups were assessed both on admission and at three-month follow-up.

RESULTS

When the complete blood count (CBC) changes of the groups included in the study were compared, the RDW, MPV, and NLR values showed a greater decrease in the NOAC group compared to the non-NOAC group (p=0.000 for all).

CONCLUSIONS

The results indicated that the NOAC used in anticoagulation treatment do not only act as anticoagulants but also reduce inflammation and platelet reactivation, which have an important role in the pathogenesis of AF and thromboembolism.

Retrospective analysis of effectiveness of fingolimod in real life setting in Turkey (REFINE)

BACKGROUND

During multiple sclerosis (MS) treatment different modes of action such as lateral (interferon beta to glatiramer acetate or glatiramer acetate to interferon beta) or vertical (interferon beta/glatiramer acetate to fingolimod) drug switch can be performed. This study aims to investigate the clinical effectiveness of switching from the first-line injectable disease modifying treatments (iDMTs) to fingolimod (FNG) compared to switching between first-line iDMTs.

METHODS

This is a multicenter, observational and retrospective study of patients with relapsing-remitting MS who had lateral and vertical switch. The observation period included three key assessment time points (before the switch, at switch, and after the switch). Data were collected from the MS patients' database by neurologists between January 2018 and June 2019. The longest follow-up period of the patients was determined as 24 months after the switch.

RESULTS

In 462 MS patients that were included in the study, both treatments significantly decreased the number of relapses during the postswitch 12 months versus preswitch one year while patients in the FNG group experienced significantly fewer relapses compared to iDMT cohort in the postswitch 12 months period. FNG cohort experienced fewer relapses than in the iDMT cohort within the postswitch 2 year. The mean time to first relapse after the switch was significantly longer in the FNG group.

DISCUSSION

The present study revealed superior effectiveness of vertical switch over lateral switch regarding the improvement in relapse outcomes. Patients in the FNG cohort experienced sustainably fewer relapses during the follow-up period after the switch compared the iDMT cohort. Importantly, switching to FNG was more effective in delaying time to first relapse when compared with iDMTs.

[A Histopathologically Diagnosed Neurocysticercosis Case from Türkiye]

Cysticercosis is a parasitic tissue infection caused by larval cysts of Taenia solium. Although the disease affects many tissues, it primarily affects the brain and muscles. The most common form is neurocysticercosis, a term used for human central nervous system involvement with T.solium cysts. Neurocysticercosis is an important public health problem in many parts of the world. Its prevalence is particularly high in places where T.solium tapeworms are common, such as Mexico, Central America, South America, Southeast Asia, Africa, China, India, and Nepal. Its incidence has been increasing rapidly in recent years in non-endemic countries, due to both import and local cases, while in some highly endemic areas, numbers appear to have decreased, possibly due to better sanitation and increased public awareness. It is extremely rare in Türkiye. Cysticercosis is usually caused by drinking water or eating food containing tapeworm eggs. Clinical manifestations can range from completely asymptomatic infection to severe illness or death. Although the infection can involve any part of the central nervous system, symptomatic patients mostly have spinal cord involvement, intracerebral lesion, intraventricular cyst or subarachnoid lesion. An intraparenchymal cerebral cyst typically grows slowly and causes minimal symptoms for years or decades after the onset of infection. The site of involvement and the symptoms experienced determine the diagnosis and treatment method. The current general consensus supports antihelmintic and corticosteroid therapy for viable parenchymal lesions. In this report, a neurocysticercosis case with a single brain lesion that was surgically removed and histologically examined was presented. The patient had complaints of lisp in the tongue, numbness in the lips and left face. The patient had no concomitant chronic disease. The patient did not have a travel history or a history of eating pork but had a history of contact with a dead pig two months ago. Upon detection of a central mass in the brain computed tomography examination, surgical procedure was performed on the patient. Based on the identification of a larval stage of T.solium in biopsy material neurocysticercosis was diagnosed. However, histopathologically demonstration of the parasite is not possible in most cases. The patient received an antiparasitic treatment with albendazole 1000 mg/d in combination with dexamethasone. The patient was successfully treated and is still being followed up by calling for controls.

Evaluation of neurological disorders that develop concurrently with COVID-19 pneumonia: a retrospective analysis

BACKGROUND

During the pandemic, many neurological symptoms have been evaluated as complications of COVID-19 pneumonia.

OBJECTIVE

To investigate the frequency and characteristics of neurological findings, and their effects on the prognosis of patients with COVID-19 pneumonia who consulted with the Neurology department.

METHODS

Data on 2329 patients who were hospitalized with the diagnosis of COVID-19 pneumonia in our hospital were scanned. The clinical, laboratory and radiological findings relating to treatment of 154 patients who required neurological consultation were retrospectively evaluated by reviewing the clinical notes.

RESULTS

The number of COVID-19 pneumonia patients who required neurological consultations while hospitalized in the ICU was 94 (61.0%). The most common symptom among these patients was hyperactive delirium. Mean age, ferritin levels and CRP values ​​of those with delirium were higher, while the mean lymphocyte percentage were lower, than those of the patients without delirium. Epileptic seizures were observed in eight patients without an epilepsy diagnosis. Two patients were diagnosed with GBS and one patient with ICU neuropathy. The D-dimer levels of patients with acute hemorrhagic CVD and the thrombocyte levels of patients with acute ischemic CVD were found to be higher than in patients without acute ischemic CVD.

CONCLUSION

The proportion of patients who required neurological consultations was higher in the ICUs. We observed neurological symptoms more frequently in the advanced age group. There were no significant increases in the incidence of other neurological conditions except delirium, in COVID-19 patients. We think that further studies are needed to support our data.

Long-term clinical course and prognosis of hot water epilepsy: 15-Year follow-up

OBJECTIVE

Hot water epilepsy (HWE) is a type of reflex epilepsy triggered by bathing with hot water. Hot water epilepsy is generally considered as a self-limiting benign disease although its long-term course and prognosis remains unknown. In this study, we aimed to determine the long-term clinical course and prognosis of hot water epilepsy and possible factors affecting them.

METHODS

The diagnosis of HWE was made based on the clinical history obtained from patients and their first degree relatives witnessing to the seizures and video recordings of seizures if available; then, the type of seizure was identified. Good prognosis was defined as patients whose seizures were controlled with or without preventive measures and who did not require antiepileptic treatment. The poor prognosis was defined as patients whose seizures continued despite preventive measures and required antiepileptic treatment.

RESULTS

The study included 50 (31 male and 19 female) patients with a mean follow-up of 17.63 ± 10.46 (median, 15.0) years. The age at onset of seizure was 14.52 ± 12.71 (median: 10.0) years. There were 38 (76%) patients in the good prognosis group. 18 (36%) of them achieved complete remission, who did not require preventive measures. In the remaining 20 (40%) patients, seizures could be controlled with only preventive measures. Seizures could be controlled with antiepileptic treatment in only 1 (2%) of 12 (24%) patients in the poor prognosis group. A significant relationship was found between the frequency of hot water seizures (HWSs) and poor prognosis (p = 0.019), as well as the presence of spontaneous seizures outside of bathing and poor prognosis (p = 0.000).

SIGNIFICANCE

Hot water epilepsy, as previously known, is not a self-limiting benign disease. Approximately ¾ of the cases have a good prognosis, but the rest are in the case of chronic epilepsy. The low response rate to antiepileptics' treatment suggests that the pathogenesis of the HWE may differ from other epilepsies.

Increased serum chemerin levels associated with carotid intima-media thickness

BACKGROUND

Elevated levels of chemerin can predict future ischemic cerebrovascular disease. Although chemerin is thought to play a role in atherosclerotic inflammation, whether circulating chemerin levels are associated with the severity of atherosclerosis remains to be determined.

OBJECTIVES

Through the use of carotid Doppler ultrasonography, our aim in this study was to investigate the relationships of serum chemerin levels with carotid intima-media thickness (CIMT) as an indicator of generalized atherosclerosis.

METHODS

This study compared 40 patients with ischemic stroke and 40 healthy subjects. Measurements were made at end-diastole using color Doppler ultrasonography (CDUS) after a 5-min rest interval in a quiet and dark room. CIMT was defined as the distance between the innermost edge of the luminal echo to the innermost edge of the media/adventitia echo. CIMT was measured in the posterior wall of both common carotid arteries within 1 cm proximally to the bulbus. Three measurements were made on both sides and the average measurement was taken as the CIMT. Serum chemerin levels were determined in all patients and healthy subjects.

RESULTS

Serum chemerin levels were significantly higher in the patient group than in the control group (p=0.004). Serum chemerin levels were positively correlated with CIMT (p<0.05). There was a significant difference between the groups with regard to CIMT (p<0.001).

CONCLUSION

Elevated serum chemerin levels appear to be associated with CIMT, thus suggesting that a link exists between chemerin and atherosclerotic ischemic cerebrovascular disease.

S100B and neuron-specific enolase levels in episodic and chronic migraine

OBJECTIVES

In recent years, radiological and biochemical data have emerged regarding the development of cellular damage in the brain of patients with migraine, calling into question what has traditionally been accepted as a benign disorder. In order to investigate whether cellular damage develops in the brain of episodic migraine patient, serum levels of neuron-specific enolase (NSE) and S100B have been evaluated in recent studies. However, contradictory results were obtained in these studies. Moreover, there is no study on NSE and S100B in cases of chronic migraine.

METHODS

Patients with episodic migraine with or without aura and chronic migraine were included. In addition, 27 healthy volunteers were included as a control group. Control group was selected from healthy volunteers of the same age and sex. We investigated serum NSE and S100B levels during the interictal period in 26 patients with episodic migraine and 27 patients with chronic migraine.

RESULTS

The serum NSE and S100B levels were significantly higher in both patients with episodic and chronic migraine than controls. Although there were no significant differences in the serum NSE and S100B levels between the two patients' groups, these markers were found to be higher in cases of chronic migraine.

CONCLUSION

These results suggest that there is both neuronal and glial involvement in the two migraine groups. Elevations in these markers in cases of episodic migraine suggest that cellular damage not only results from headache episodes, but that there may be also an ongoing pathological process during the interictal period.

Epileptic olfactory auras: a clinical spectrum

OBJECTIVE

To investigate the relative frequency of olfactory aura in a large number of patients with focal epilepsy, and examine the full clinical spectrum of epileptic olfactory auras (OAs) and their relationship to hemispheric lateralization and localization of epileptogenic focus.

METHODS

This retrospective study was based on the medical records of 1384 patients with focal epilepsy. Of these, 71 (5.1%) patients were present with OAs, comprising 25 (35.2%) men and 46 (64.8%) women with a mean age of 35.43 ± 12.89 years. These 71 patients were classified according to the clinical features of the OAs, and the electroencephalography and magnetic resonance imaging findings were examined.

RESULTS

The relative frequency of OAs was 5.1% in the focal epileptic patients. The clinical spectrum of OAs in our cases was outlined as follows, complex OAs and elementary OAs. Elementary OAs were divided into three subgroups: elementary neutral OAs, elementary unpleasant OAs, and elementary pleasant OAs. In our cases, there was no difference between the right and left hemispheres in terms of lateralization of the epileptogenic focus. In all the 71 patients, the epileptogenic zone was most commonly localized in the temporal lobe (n = 58; 81.7%).

CONCLUSIONS

The relative frequency of OAs in focal epilepsies is likely to be found higher than expected. Elementary OAs occur much more frequently than complex OAs. Among the elementary OAs, elementary unpleasant OAs and elementary neutral OAs are the most common types, whereas elementary pleasant OAs are extremely rare.

Changes in Neuroendovascular Procedural Volume During the COVID-19 Pandemic: An International Multicenter Study

BACKGROUND AND PURPOSE

The effect of coronavirus disease 2019 (COVID‐19) pandemic on performance of neuroendovascular procedures has not been quantified.

METHODS

We performed an audit of performance of neuroendovascular procedures at 18 institutions (seven countries) for two periods; January‐April 2019 and 2020, to identify changes in various core procedures. We divided the region where the hospital was located based on the median value of total number of COVID‐19 cases per 100,00 population‐into high and low prevalent regions.

RESULTS

Between 2019 and 2020, there was a reduction in number of cerebral angiograms (30.9% reduction), mechanical thrombectomy (8% reduction), carotid artery stent placement for symptomatic (22.7% reduction) and asymptomatic (43.4% reduction) stenoses, intracranial angioplasty and/or stent placement (45% reduction), and endovascular treatment of unruptured intracranial aneurysms (44.6% reduction) and ruptured (22.9% reduction) and unruptured brain arteriovenous malformations (66.4% reduction). There was an increase in the treatment of ruptured intracranial aneurysms (10% increase) and other neuroendovascular procedures (34.9% increase). There was no relationship between procedural volume change and intuitional location in high or low COVID‐19 prevalent regions. The procedural volume reduction was mainly observed in March‐April 2020.

CONCLUSIONS

We provided an international multicenter view of changes in neuroendovascular practices to better understand the gaps in provision of care and identify individual procedures, which are susceptible to change.

Is it possible to detect cerebral dominance via EEG signals by using deep learning?

Each brain hemisphere is dominant for certain functions such as speech. The determination of speech laterality prior to surgery is of paramount importance for accurate risk prediction. In this study, we aimed to determine speech laterality via EEG signals by using noninvasive machine learning techniques. The retrospective study included 67 subjects aged 18-65 years who had no chronic diseases and were diagnosed as healthy based on EEG examination. The subjects comprised 35 right-hand dominant (speech center located in the left hemisphere) and 32 left-hand dominant individuals (speech center located in the right hemisphere). A spectrogram was created for each of the 18 EEG channels by using various Convolutional Neural Networks (CNN) architectures including VGG16, VGG19, ResNet, MobileNet, NasNet, and DenseNet. These architectures were used to extract features from the spectrograms. The extracted features were classified using Support Vector Machines (SVM) and the classification performances of the CNN models were evaluated using Area Under the Curve (AUC). Of all the CNN models used in the study, VGG16 had a higher AUC value (0.83 ± 0.05) in the determination of speech laterality compared to all other models. The present study is a pioneer investigation into the determination of speech laterality via EEG signals with machine learning techniques, which, to our knowledge, has never been reported in the literature. Moreover, the classification results obtained in the study are promising and lead the way for subsequent studies though not practically feasible.

Acute Rhinosinusitis as an Infrequent Cause of Symptomatic Cluster Headache: Report of Seven Cases

Cluster headache (CH) is a primary headache disorder characterized by unilateral headache attacks lasting 15 to 180 minutes, occurring between two and eight times a day, and accompanied by autonomic symptoms ipsilateral to the pain. However, cases of symptomatic CH that occur secondary to an underlying structural pathology have also been reported in the literature. In this report, seven patients are presented who were admitted with signs of CH and diagnosed with acute rhinosinusitis depending on extensive clinical and radiologic examinations. Symptomatic CH, though rarely reported in the literature compared to CH, should be kept in mind in patients presenting with the first attack of CH. Moreover, in such patients, whether the pain becomes worse when bending forward and becomes sensitive on palpation should be questioned, and a radiologic work-up should be performed to rule out secondary causes such as rhinosinusitis. In the present cases, the resolution of CH attacks with acute sinusitis therapy confirmed the diagnosis.

Undifferentiated headache: broadening the approach to headache in children and adolescents, with supporting evidence from a nationwide school-based cross-sectional survey in Turkey

BACKGROUND

Headache is a leading disabler in adults worldwide. In children and adolescents, the same may be true but the evidence is much poorer. It is notable that published epidemiological studies of these age groups have largely ignored headaches not fulfilling any specific set of ICHD criteria, although such headaches appear to be common. A new approach to these is needed: here we introduce, and investigate, a diagnostic category termed "undifferentiated headache" (UdH), defined in young people as recurrent mild-intensity headache of < 1 h's duration.

METHODS

We conducted a nationwide cross-sectional survey in 31 schools in six regions of Turkey selected by mixed convenience-based and purposive modified cluster-sampling. A validated, standardised self-completed structured questionnaire was administered by a physician-investigator to entire classes of pupils aged 6-17 years.

RESULTS

Of the identified sample of 7889 pupils, 7088 (89.8%) participated. The 1-year prevalence of UdH was 29.2%, of migraine (definite and probable) 26.7%, and of tension-type headache (TTH) (definite and probable) 12.9%. UdH differed with respect to almost all headache features and associated symptoms from both migraine and TTH. Burden of headache and use of acute medication were lower in UdH than in migraine and TTH. Headache yesterday was less common in UdH than migraine (OR 0.32; 95% CI 0.28-0.37) and TTH (OR 0.64; 95% CI 0.56-0.77). Quality of life (QoL) was better in UdH (33.6 ± 5.2) than in migraine (30.3 ± 5.6; p < 0.001) and TTH (32.4 ± 5.3; p < 0.001), but worse than in pupils without headache (35.7 ± 4.7; p < 0.001).

CONCLUSIONS

This large nationwide study in Turkey of pupils aged 6-17 years has shown that many children and adolescents have a headache type that does not conform to existing accepted diagnostic criteria. This new diagnostic category of presumably still-evolving headache (undifferentiated headache) is common. UdH differs in almost all measurable respects from both migraine and TTH. Although characterised by mild headaches lasting < 1 h, UdH is associated with significant adverse impact on QoL. Longitudinal cohort studies are needed to evaluate the prognosis of UdH but, meanwhile, recognition of UdH and its distinction from migraine and TTH has implications for epidemiological studies, public-health policy and routine clinical practice.

A case of syncopal convulsions triggered by glossopharyngeal neuralgia

Syncopal convulsions and epileptic seizures are clinically hard to distinguish and differ in terms of treatment approaches. It is important to consider the cardiac arrhythmias that impair cerebral perfusion in the differential diagnosis of antiepileptic treatment-resistant convulsions. Here we offer a 72 year old male patient glossopharengial neuralgia after swallowing associated with recurrent episodes of syncopal convulsions. The patient was successfully treated with temporary pacemaker and carbamazepine. This phenomenon is noteworthy in terms of both asystole triggered by glossopharengial neuralgia and syncopal convulsions which are rare in the differential diagnosis of epileptic seizures.