Publications by authors named "Ashkan Pakzad"
Article Synopsis
- - This study addresses the challenges of accurately segmenting airway trees in the context of diagnosing and characterizing chronic respiratory diseases, emphasizing the limitations of existing traditional methods requiring manual adjustments due to inconsistent segmentation results.
- - It introduces a novel deep learning approach called Interpolation-Split, which enhances segmentation performance by improving data quality through interpolation and image splitting, while also being efficient in terms of computational resource usage.
- - The results show that this new method significantly outperforms previous models in segmentation accuracy, achieving high dice similarity coefficients while requiring less GPU memory, making it more accessible for various computational environments.
Small airway disease is an important pathophysiological feature of chronic obstructive pulmonary disease (COPD). Recently, "pre-COPD" has been put forward as a potential precursor stage of COPD that is defined by abnormal spirometry findings or significant emphysema on computed tomography (CT) in the absence of airflow obstruction. To determine the degree and nature of (small) airway disease in pre-COPD using microCT in a cohort of explant lobes/lungs.
View Article and Find Full Text PDFBackground: Tremor in Parkinson's disease (PD) has an inconsistent response to levodopa and subthalamic deep brain stimulation (STN-DBS).
Objectives: To identify predictive factors of PD tremor responsiveness to levodopa and STN-DBS.
Material And Methods: PD patients with upper limb tremor who underwent STN-DBS were included.
Background And Objectives: Deep brain stimulation (DBS) of the ventral tegmental area (VTA) is a surgical treatment option for selected patients with refractory chronic cluster headache (CCH). We aimed to identify clinical and structural neuroimaging factors associated with response to VTA DBS in CCH.
Methods: This prospective observational cohort study examines consecutive patients with refractory CCH treated with VTA DBS by a multidisciplinary team in a single tertiary neuroscience center as part of usual care.
Article Synopsis
- Open international challenges are now the main way to evaluate algorithms for computer vision and image analysis, especially in pulmonary airway segmentation.
- A new challenge, ATM'22, was organized to provide a large-scale dataset of 500 annotated CT scans to help improve algorithm performance in this area.
- The results showed that deep learning models that enhanced topological continuity performed best, and the challenge offers an open-call design for accessing data and evaluations.
Objectives: The study examined whether quantified airway metrics associate with mortality in idiopathic pulmonary fibrosis (IPF).
Methods: In an observational cohort study (n = 90) of IPF patients from Ege University Hospital, an airway analysis tool AirQuant calculated median airway intersegmental tapering and segmental tortuosity across the 2nd to 6th airway generations. Intersegmental tapering measures the difference in median diameter between adjacent airway segments.
Bronchiectasis is a radiological diagnosis made using computed tomographic (CT) imaging. Although visual CT assessment is necessary for the diagnosis of bronchiectasis, visual assessment of disease severity and progression is challenging. Computer tools offer the potential to improve the characterization of lung damage in patients with bronchiectasis.
View Article and Find Full Text PDFThe Antikythera Mechanism is an extraordinarily complex ancient Greek astronomical calculating device whose mode of operation is now relatively well understood particularly since imaging studies in 2005 revealed gears and inscriptions which were previously illegible. Unfortunately, the highest resolution X-ray computed tomography image of the largest fragment had some errors which meant that the reconstructed images were not as clear as had been expected. Here, the original X-ray data have been reanalysed and reconstructed.
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