Publications by authors named "S S Karhula"
Purpose: Effects of clinical radiotherapy are often studied between or after irradiations. The current study's aim was to monitor an immediate irradiation response in cerebral water and hemodynamics in patients treated with whole brain radiotherapy (WBRT) and to assess the response's individuality.
Methods: We used functional near-infrared spectroscopy (fNIRS) to monitor changes in cerebral water, oxyhemoglobin (HbO), and deoxyhemoglobin (HbR) during the irradiation of 31 patients (age 69.
Article Synopsis
- The study evaluates two synthetic computed tomography (sCT) algorithms—bulk-density-method (BM) and artificial intelligence (AI)—for generating CT images from MRI data in prostate radiotherapy.
- It involved 44 patients who underwent both MRI and treatment planning CT (TPCT), with the sCT images analyzed for their accuracy in dose coverage and alignment accuracy compared to TPCT.
- Results indicated that while AI-sCT had slightly better dose coverage and alignment accuracy, both methods performed similarly in clinical relevance, with differences in dose coverage and gamma-analysis passing rates being insignificant overall.
Purpose: Clinical cone-beam computed tomography (CBCT) devices are limited to imaging features of half a millimeter in size and cannot quantify the tissue microstructure. We demonstrate a robust deep-learning method for enhancing clinical CT images, only requiring a limited set of easy-to-acquire training data.
Methods: Knee tissue from five cadavers and six total knee replacement patients, and 14 teeth from eight patients were scanned using laboratory CT as training data for the developed super-resolution (SR) technique.
Significance: Cancer therapy treatments produce extensive changes in the physiological and morphological properties of tissues, which are also individual dependent. Currently, a key challenge involves developing more tailored cancer therapy, and consequently, individual biological response measurement during therapy, such as tumor hypoxia, is of high interest. This is the first time human cerebral haemodynamics and cerebral tissue oxygenation index (TOI) changes were measured during the irradiation in clinical radiotherapy and functional near-infrared spectroscopy (fNIRS) technique was demonstrated as a feasible technique for clinical use in radiotherapy, based on 34 online patient measurements.
View Article and Find Full Text PDFIn this study, we aimed to precisely localize the hyperintense signal that is generated at the osteochondral junction when using ultrashort echo time magnetic resonance imaging (MRI) and to investigate the osteochondral junction using sweep imaging with Fourier transformation (SWIFT) MRI. Furthermore, we seek to evaluate what compositional properties of the osteochondral junction are the sources of this signal. In the study, we obtained eight samples from a tibial plateau dissected from a 68-year-old male donor, and one additional osteochondral sample of bovine origin.
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