276 research outputs found
PREDICTION OF SEPSIS DISEASE BY ARTIFICIAL NEURAL NETWORKS
Sepsis is a fatal condition, which affects at least 26 million people in the world every year that is resulted by an infection. For every 100,000 people, sepsis is seen in 149-240 of them and it has a mortality rate of 30%. The presence of infection in the patient is determined in order to diagnose the sepsis disease. Organ dysfunctions associated with an infection is diagnosed as sepsis. With the increased usage of artificial intelligence in the field of medicine, the early prediction and treatment of many diseases are provided with these methods. Considering the learning, reasoning and decision making abilities of artificial neural networks, which are the sub field of artificial intelligence are inferred to be used in predicting early stages of sepsis disease and determining the sepsis level is assessed. In this study, it is aimed to help sepsis diagnosis by using multi-layered artificial neural network.In construction of artificial neural network model, feed forward back propagation network structure and Levenberg-Marquardt training algorithm were used. The input and output variables of the model were the parameters which doctors use to diagnose the sepsis disease and determine the level of sepsis. The proposed method aims to provide an alternative prediction model for the early detection of sepsis disease
MOBİL HİDROLİK TELESKOBİK VİNÇLERDE YÜK SALINIM KONTROLÜ
Bu çalışmada, mobil hidrolik teleskobik bir vincin öncelikle tasarımı yapılmış ve burada bir yük ile vinç tanımlanmıştır. Tasarlanan teleskopik vinç gerçek sistemdeki veriler dahil edilerek Matlab/Simulink programında modellenmiştir. Giriş sinyalleri etkisiyle oluşan salınım ölçülüp bu salınımı kabul edilebilir toleranslar dahiline düşürebilecek kontrolcü tasarlanmıştır. Çalışmanın ana hedefi, mobil teleskobik vinçlerin kaldırma silindirleri ve dönme merkezindeki tork tahriki ile hareket etmesi sonucu teleskobik vince bir halat vasıtasıyla bağlı olan yükün x, y, z referans eksenlerine göre açılı bir şekilde oluşan salınımını kontrolcü kullanarak minimize etmektir. Sistemin başarı kriteri, uygulamada ergonomik bir çalışma zemini hazırlayacak şekilde salınımı azaltmak olacaktır. Göz önüne alınması gereken bir diğer nokta ise vinci kullanacak operatörden bağımsız bir şekilde bu kontrolü sağlamak olacaktır.
MOBİL HİDROLİK TELESKOBİK VİNÇLERDE YÜK SALINIM KONTROLÜ
Bu çalışmada, mobil hidrolik teleskobik bir vincin öncelikle tasarımı yapılmış ve burada bir yük ile vinç tanımlanmıştır. Tasarlanan teleskopik vinç gerçek sistemdeki veriler dahil edilerek Matlab/Simulink programında modellenmiştir. Giriş sinyalleri etkisiyle oluşan salınım ölçülüp bu salınımı kabul edilebilir toleranslar dahiline düşürebilecek kontrolcü tasarlanmıştır. Çalışmanın ana hedefi, mobil teleskobik vinçlerin kaldırma silindirleri ve dönme merkezindeki tork tahriki ile hareket etmesi sonucu teleskobik vince bir halat vasıtasıyla bağlı olan yükün x, y, z referans eksenlerine göre açılı bir şekilde oluşan salınımını kontrolcü kullanarak minimize etmektir. Sistemin başarı kriteri, uygulamada ergonomik bir çalışma zemini hazırlayacak şekilde salınımı azaltmak olacaktır. Göz önüne alınması gereken bir diğer nokta ise vinci kullanacak operatörden bağımsız bir şekilde bu kontrolü sağlamak olacaktır
Utility of Hounsfield unit in the diagnosis of tandem occlusion in acute ischemic stroke
Background Tandem occlusions can complicate medical and endovascular stroke treatment. To identify these occlusions,
computed tomography angiography (CTA) represents the best imaging modality. However, CTA is still not initially performed
in some patients not admitted directly to stroke centers. Early identification of an additional occlusion of the proximal extracranial
internal carotid artery may improve the best suitable treatment strategy. The purpose of this study was to find a valuable threshold
of thrombus attenuation in a non-contrast head CT (NCCT) scan to facilitate a safe diagnosis of tandem occlusions.
Materials and methods Consecutive patients with acute middle cerebral artery (MCA) occlusions who underwent endovascular
treatment were identified from our registry of neuroendovascular interventions. Thrombus attenuations of the affected MCA and
contralateral vessel were measured by NCCT. To compare individual baseline blood attenuations, the difference between the
thrombus attenuation and the contralateral MCA attenuation (referred to as ΔTM) was calculated.
Results Three hundred and twenty-five patients were included. There was a highly significant difference between mean thrombus
attenuation with isolated MCA occlusion and additional extracranial internal carotid artery (ICA) occlusion (49.9 ± 8 vs. 56.2 ±
10 Hounsfield units (HU); P < 0.001). The area under the receiver operating characteristic curve of ΔTM was 0.72. The optimal
threshold value was 13.5 HU, with a sensitivity of 67.5% and a specificity of 68.6%.
Conclusion Despite a significant difference in thrombus attenuation in MCA occlusions with an additional extracranial ICA
occlusion compared with isolated MCA occlusions, a relevant threshold of thrombus attenuation was not found
Recurrent reversible in-stent-stenosis after flow diverter treatment
Flow diverter stents (FDS) are well established in the treatment of intracranial aneurysms which are difcult to treat with
conventional endovascular techniques. However, they carry a relatively high risk of specifc complications compared to
conventional stents. A minor but frequent fnding is the occurrence of reversible in-stent-stenosis (ISS) that tend to resolve
spontaneously over time. Here, we report the case of a patient in their 30s who was treated with FDS for bilateral paraophthalmic internal carotid artery (ICA) aneurysms. ISS were found at the respective early follow-up examinations on both sides and
had resolved at the 1-year follow-up examinations. Surprisingly ISS reoccurred at both sides in later follow-up examinations
and again resolved spontaneously. The recurrence of ISS after resolution is a fnding that has not been described previously.
Its incidence and further development should be investigated systematically. This might contribute to our understanding of
the mechanisms underlying the efect of FDS
Acute stroke treatment and outcome in the oldest old (90 years and older) at a tertiary care medical centre in Germany-a retrospective study showing safety and efficacy in this particular patient population
Background
Stroke is among the most common causes of death and disability worldwide. Despite the relevance of stroke-related disease burden, which is constantly increasing due to the demographic change in industrialized countries with an ageing population and consecutively an increase in age-associated diseases, there is sparse evidence concerning acute stroke treatment and treatment-related outcome in the elderly patient group. This retrospective study aimed at analysing patient characteristics, therapy-related complications and functional outcome in stroke patients aged 90 years or older who underwent acute stroke treatment (i.e. intravenous thrombolysis, mechanical thrombectomy, or both).
Methods
We identified files of all inpatient stays at the Department of Neurology at Saarland University Medical Center (tertiary care level with a comprehensive stroke unit) between June 2011 and December 2018 and filtered for subjects aged 90 years or older at the time of admission. We reviewed patient files for demographic data, symptoms upon admission, (main) diagnoses, comorbidities, and administered therapies. For patients admitted due to acute stroke we reviewed files for therapy-related complications and functional outcome. We compared the modified Rankin scale (mRS) scores upon admission and at discharge for these patients.
Results
We identified 566 inpatient stays of subjects aged 90 years or older. Three hundred sixty-seven of the 566 patients (64.8%) were admitted and discharged due to symptoms indicative of stroke. Two hundred eleven patients received a diagnosis of ischaemic stroke. These 211 patients were analysed subsequently. Sixty-four patients qualified for acute stroke treatment (intravenous thrombolysis n = 22, mechanical thrombectomy n = 26, intravenous thrombolysis followed by mechanical thrombectomy n = 16) and showed a significant improvement in their functional status as measured by change in mRS score (admission vs. discharge, p 0.001) with 7 (10.9%) observed potentially therapy-related complications (relevant drop in haemoglobin n = 2, subarachnoidal haemorrhage n = 1, cerebral haemorrhage n = 3, extracranial bleeding n = 1). One intravenous thrombolysis was stopped because of an uncontrollable hypertensive crisis. Patients who did not qualify for these treatments (including those declining acute treatment) did not show a change of their functional status between admission and discharge (p 0.064).
Conclusion
Our data indicate that acute stroke treatment is effective and safe in the oldest old. Age alone is no criterion to withhold an acute intervention even in oldest old stroke patients
Treatment of experimental aneurysms with a GPX embolic agent prototype: preliminary angiographic and histological results
Background Recently, liquid embolic agents have
emerged for the endovascular treatment of cerebral
aneurysms. Here we describe the in vivo performance of
a novel liquid embolization agent (GPX Embolic Device).
Methods Elastase-induced aneurysms were embolized
with a GPX prototype under balloon assistance. Digital
subtraction angiography was performed pre-deployment
and immediately after, and at 5, 10, and 30min postdeployment in 10 rabbits and at 1month in 8 rabbits. The
early post-deployment intra-aneurysmal flow was graded
as unchanged, moderately diminished, or completely
absent. At 1month the status of aneurysm occlusion was
evaluated. Adhesion to catheter material and migration
of GPX was assessed.
Results The mean aneurysm neck diameter, width, and
height were 3.6±1.0mm, 3.0±0.8mm, and 7.4±1.4mm,
respectively. The mean dome-to-neck ratio was 0.9±0.2.
Complete stagnation of intra-aneurysmal flow was
observed in 9 of 10 aneurysms (90%) within 30min of
device deployment. One aneurysm showed moderately
diminished intra-aneurysmal flow at 30min. At 1month,
8 aneurysms were completely occluded. There was no
evidence of GPX adhesion to the catheter material.
Histologically, a leukocyte and foreign body reaction to
GPX was detectable 28 days after embolization.
Conclusions This is the first preclinical study reporting
the performance of a protype version of the GPX Embolic
Device in a wide-neck aneurysm model. GPX showed
promising results by achieving and maintaining high
rates of complete angiographic occlusion, but may
induce an inflammatory reaction
Pott's puffy tumor: a need for interdisciplinary diagnosis and treatment
Pott’s puffy tumor (PPT) is an infection of the frontal sinus with subperiosteal and intracranial abscess formation and one of the rare entities in pediatrics. We present a series of four cases of PPT that occurred in two children (6 and 9 years) and in two young adults (17 and 19 years). All patients were treated by an interdisciplinary team of pediatric, neurosurgical, ENT, radiological, and neuroradiological specialists. Antibiotic treatment was combined with single endoscopic surgery in one case and combined endoscopic sinus surgery with an open transcranial approach to drain intracranial abscess formation in three cases. It is important to be aware that PPT occurs in children with the finding of intracranial abscess formation. Therefore, a close interdisciplinary cooperation for successful treatment is needed in this rare disease
Why we fail: mechanisms and co-factors of unsuccessful thrombectomy in acute ischemic stroke
Purpose Mechanical thrombectomy (MT) is an effective treatment for patients suffering from acute ischemic stroke. However,
recanalization fails in about 16.5% of interventions. We report our experience with unsuccessful MT and analyze technical
reasons plus patient-related parameters for failure.
Methods Five hundred ninety-six patients with acute ischemic stroke in the anterior circulation and intention to perform MT with
an aspiration catheter and/or stent retriever were analyzed. Failure was defined as 0, 1, or 2a on the mTICI scale. Patients with
failing MT were analyzed for interventional progress and compared to patients with successful intervention, whereby parameters
included demographics, medical history, stroke presentation, and treatment.
Results One hundred of the 596 (16.8%) interventions failed. In 20 cases, thrombus could not be accessed or passed with the
device. Peripheral arterial occlusive disease is common in those patients. In 80 patients, true stent retriever failure occurred. In this
group, coagulation disorders are associated with poor results, whereas atrial fibrillation is associated with success.
The administration of intravenous thrombolysis and intake of nitric oxide donors are associated with recanalization success.
Intervention duration was significantly longer in the failing group.
Conclusion In 20% of failing MT, thrombus cannot be reached/passed. Direct carotid puncture or surgical arterial access could be
considered in these cases.
In 80% of failing interventions, thrombus can be passed with the device, but the occluded vessel cannot be recanalized. Rescue
techniques can be an option. Development of new devices and techniques is necessary to improve recanalization rates.
Assessment of pre-existing illness could sensitize for occurring complications
Different Rescue Approaches of Migrated Woven Endobridge (WEB) Devices: an Animal Study
Purpose Treatment of wide-necked intracranial aneurysms using the Woven Endobridge (WEB) device has become
broadly accepted. Feared complications with the potential of increased poor clinical outcome include dislocations and
migration of the device. This study was carried out to determine the effectiveness of a variety of different strategies to
rescue migrated WEB devices.
Methods In a porcine model, WEB devices of different sizes (SL [single layer] 3.5 × 2mm and SL 4.0 × 3mm, SL 8 × 5mm
and SLS 8mm [single layer spherical]) were placed into both the subclavian and axillary arteries. A total of 32 rescue
maneuvers (8 per rescue device) were performed. Small WEBs were rescued using reperfusion catheters (RC) (SOFIA Plus
and JET 7), larger WEBs were rescued using dedicated rescue devices (Microsnare and Alligator). Rescue rates, times,
attempts and complications were assessed.
Results Rescue attempts of migrated WEBs were successful in all cases (100%). Rescue time (p= 0.421) and attempts
(p= 0.619) of small WEBs using RCs were comparable without significant differences. Aspiration alone was not successful
for larger WEBs. Rescue of larger WEBs was slightly faster (122.75 ± 41.15 s vs. 137.50 ± 54.46 s) with fewer attempts (1
vs. 1.37) when using the Microsnare compared to the Alligator device. Complications such as entrapment of the WEB in
the RCs, vasospasm, perforation, or dissection were not observed.
Conclusion Rescue of migrated WEB devices is a feasible and effective method and 100% successful rescue rates and
appropriate rescue times can be achieved for small WEBs using RCs and for larger WEBs using dedicated rescue devices
(Microsnare and Alligator)
- …