Browsing by Subject "VOLUME"

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  • Murtola, Tiina; Malinen, Jarmo; Geneid, Ahmed; Alku, Paavo (2019)
    A multichannel dataset comprising high-speed videoendoscopy images, and electroglottography and free-field microphone signals, was used to investigate phonation onsets in vowel production. Use of the multichannel data enabled simultaneous analysis of the two main aspects of phonation, glottal area, extracted from the high-speed videoendoscopy images, and glottal flow, estimated from the microphone signal using glottal inverse filtering. Pulse-wise parameterization of the glottal area and glottal flow indicate that there is no single dominant way to initiate quasi-stable phonation. The trajectories of fundamental frequency and normalized amplitude quotient, extracted from glottal area and estimated flow, may differ markedly during onsets. The location and steepness of the amplitude envelopes of the two signals were observed to be closely related, and quantitative analysis supported the hypothesis that glottal area and flow do not carry essentially different amplitude information during vowel onsets. Linear models were used to predict the phonation onset times from the characteristics of the subsequent steady phonation. The phonation onset time of glottal area was found to have good predictability from a combination of the fundamental frequency and the normalized amplitude quotient of the glottal flow, as well as the gender of the speaker. For the phonation onset time of glottal flow, the best linear model was obtained using the fundamental frequency and the normalized amplitude quotient of the glottal flow as predictors.
  • FINNAKI Study Grp (2019)
    Background Injury to endothelium and glycocalyx predisposes to vascular leak, which may subsequently lead to increased fluid requirements and worse outcomes. In this post hoc study of the prospective multicenter observational Finnish Acute Kidney Injury (FINNAKI) cohort study conducted in 17 Finnish intensive care units, we studied the association of Syndecan-1 (SDC-1), Angiopoetin-2 (Ang-2), soluble thrombomodulin (sTM), vascular adhesion protein-1 (VAP-1) and interleukin-6 (IL-6) with fluid administration and balance among septic critical care patients and their association with development of acute kidney injury (AKI) and 90-day mortality. Results SDC-1, Ang-2, sTM, VAP-1 and IL-6 levels were measured at ICU admission from 619 patients with sepsis. VAP-1 decreased (p <0.001) and IL-6 increased (p <0.001) with increasing amounts of administered fluid, but other biomarkers did not show differences according to fluid administration. In linear regression models adjusted for IL-6, only VAP-1 was significantly associated with fluid administration on day 1 (p <0.001) and the cumulative fluid balance on day 5/ICU discharge (p = 0.001). Of 415 patients admitted without AKI, altogether 112 patients (27.0%) developed AKI > 12 h from ICU admission (AKI(>12 h)). They had higher sTM levels than patients without AKI, and after multivariable adjustment log, sTM level was associated with AKI(>12 h) with OR (95% CI) of 12.71 (2.96-54.67), p = 0.001). Ninety-day non-survivors (n = 180; 29.1%) had higher SDC-1 and sTM levels compared to survivors. After adjustment for known confounders, log SDC-1 (OR [95% CI] 2.13 [1.31-3.49], p = 0.002), log sTM (OR [95% CI] 7.35 [2.29-23.57], p <0.001), and log Ang-2 (OR [95% CI] 2.47 [1.44-4.14], p = 0.001) associated with an increased risk for 90-day mortality. Finally, patients who had high levels of all three markers, namely, SDC-1, Ang-2 and sTM, had an adjusted OR of 5.61 (95% CI 2.67-11.79; p <0.001) for 90-day mortality. Conclusions VAP-1 and IL-6 associated with fluid administration on the first ICU day. After adjusting for confounders, sTM was associated with development of AKI after 12 h from ICU admission. SDC-1, Ang-2 and sTM were independently associated with an increased risk for 90-day mortality.
  • Kangas, Annika; Raty, Minna; Korhonen, Kari T.; Vauhkonen, Jari; Packalen, Tuula (2019)
    Forest information is needed at global, national and local scales. This review aimed at providing insights of potential of national forest inventories (NFIs) as well as challenges they have to cater to those needs. Within NFIs, the authors address the methodological challenges introduced by the multitude of scales the forest data are needed, and the challenges in acknowledging the errors due to the measurements and models in addition to sampling errors. Between NFIs, the challenges related to the different harmonization tasks were reviewed. While a design-based approach is often considered more attractive than a model-based approach as it is guaranteed to provide unbiased results, the model-based approach is needed for downscaling the information to smaller scales and acknowledging the measurement and model errors. However, while a model-based inference is possible in small areas, the unknown random effects introduce biased estimators. The NFIs need to cater for the national information requirements and maintain the existing time series, while at the same time providing comparable information across the countries. In upscaling the NFI information to continental and global information needs, representative samples across the area are of utmost importance. Without representative data, the model-based approaches enable provision of forest information with unknown and indeterminable biases. Both design-based and model-based approaches need to be applied to cater to all information needs. This must be accomplished in a comprehensive way In particular, a need to have standardized quality requirements has been identified, acknowledging the possibility for bias and its implications, for all data used in policy making.
  • Turunen, Antti; Partanen, Anu; Valtola, Jaakko; Ropponen, Antti; Siitonen, Timo; Kuittinen, Outi; Kuitunen, Hanne; Putkonen, Mervi; Sankelo, Marja; Keskinen, Leena; Savolainen, Eeva-Riitta; Pyörälä, Marja; Kuittinen, Taru; Silvennoinen, Raija; Penttilä, Karri; Sikiö, Anu; Vasala, Kaija; Mäntymaa, Pentti; Pelkonen, Jukka; Varmavuo, Ville; Jantunen, Esa (2020)
    BACKGROUND Autologous stem cell transplantation is an established treatment option for patients with multiple myeloma (MM) or non-Hodgkin?s lymphoma (NHL). STUDY DESIGN AND METHODS In this prospective multicenter study, 147 patients with MM were compared with 136 patients with NHL regarding the mobilization and apheresis of blood CD34+ cells, cellular composition of infused blood grafts, posttransplant recovery, and outcome. RESULTS Multiple myeloma patients mobilized CD34+ cells more effectively (6.3???106/kg vs. 3.9???106/kg, p?=?0.001). The proportion of poor mobilizers (peak blood CD34+ cell count 100?days) nonrelapse mortality (NRM; 6% vs. 0%, p?=?0.003). CONCLUSIONS Non-Hodgkin?s lymphoma and MM patients differ in terms of mobilization of CD34+ cells, graft cellular composition, and posttransplant recovery. Thus, the optimal graft characteristics may also be different.
  • Söderström, Henna K.; Rasanen, Jari; Saarnio, Juha; Toikkanen, Vesa; Tyrväinen, Tuula; Rantanen, Tuomo; Valtola, Antti; Ohtonen, Pasi; Pääaho, Minna; Kokkola, Arto; Kallio, Raija; Karttunen, Tuomo J.; Pohjanen, Vesa-Matti; Ristimäki, Ari; Laine, Simo; Sihvo, Eero; Kauppila, Joonas H. (2020)
    Purpose The Finnish National Esophago-Gastric Cancer Cohort (FINEGO) was established to combine the available registry data with detailed patient information to form a comprehensive, retrospective, population-based research platform of surgically treated oesophageal and gastric cancer in Finland. This cohort profile describes the 2045 surgically treated patients with oesophageal cancer included in the FINEGO cohort. Participants Registry data were collected from the National Cancer, Patient, Education and Death Registries from 1 January 1987 to 31 December 2016. All patients over 18 years of age, who had either curative surgery, palliative surgery or salvage surgery for primary cancer in the oesophagus are included in this study. Findings to date 2045 patients had surgery for oesophageal cancer in the selected time period. 67.2% were man, and the majority had only minor comorbidities. The proportions of adenocarcinomas and squamous cell carcinomas were 43.1% and 44.4%, respectively, and 12.5% had other or missing histology. Only about 23% of patients received neoadjuvant therapy. Oesophagectomy was the treatment of choice and most patients were treated at low-volume centres, but median annual hospital volume increased over time. Median overall survival was 23 months, 5-year survival for all patients in the cohort was 32.9% and cancer-specific survival was 36.5%. Future plans Even though Finland only has a population of 5.5 million, surgery for oesophageal carcinoma has not been centralised and therefore previously reported results have mostly been small, single-centre cohorts. Because of FINEGO, we now have a population-based, unselected cohort of surgically treated patients, enabling research on national trends over time regarding oesophageal cancer, including patient characteristics, tumour histology, stage and neoadjuvant treatment, surgical techniques, hospital volumes and patient mortality. Data collection is ongoing, and the cohort will be expanded to include more detailed data from patient records and national biobanks.
  • Satopaa, Jarno; Mustanoja, Satu; Meretoja, Atte; Putaala, Jukka; Kaste, Markku; Niemela, Mika; Tatlisumak, Turgut; Strbian, Daniel (2017)
    Background and aims: We evaluated the accuracy of 19 published prognostic scores to find the best tool for predicting mortality after intracerebral hemorrhage (ICH). Methods: A retrospective single-center analysis of consecutive patients with ICH (n = 1013). After excluding patients with missing data (n = 131), we analyzed 882 patients for 3-month (primary outcome), in-hospital, and 12-month mortality. We analyzed the strength of the individual score components and calculated the c-statistics, Youden index, sensitivity, specificity, negative and positive predictive value (NPV and PPV) for the scores. Finally, we included every score component in a multivariable model to analyze the maximum predictive value of the data elements combined. Results: Observed in-hospital mortality was 23.6%, 3-month mortality was 31.0%, and 12-month mortality was 35.3%. For in-hospital mortality, the National Institutes of Health Stroke Scale (NIHSS) performed equally good as the best score for the other outcomes, the ICH Functional Outcome Score (ICH-FOS). The c-statistics of the scores varied from 0.6293 (95% CI 0.587-0.672) to 0.8802 (0.855-0.906). With all variables from all the scores in a multivariable regression model, the c-statistics did not improve, being 0.89 (0.867-0.913). Using the Youden index cutoff for the ICH-FOS score, the sensitivity (73%), specificity (90%), PPV (76%), and NPV (88%) for the primary outcome were good. Conclusions: A plethora of scores exists to help clinicians estimate the prognosis of an acute ICH patient. The NIHSS can be used to quantify the risk of in-hospital death while the ICH-FOS performed best for the other outcomes. (C) 2017 Elsevier B.V. All rights reserved.
  • Budtz-Lilly, Jacob; Bjorck, Martin; Venermo, Maarit; Debus, Sebastian; Behrendt, Christian-Alexander; Altreuther, Martin; Beiles, Barry; Szeberin, Zoltan; Eldrup, Nikolaj; Danielsson, Gudmundur; Thomson, Ian; Wigger, Pius; Khashram, Manar; Loftus, Ian; Mani, Kevin (2018)
    Objectives: Current management of ruptured abdominal aortic aneurysms (RAAA) varies among centres and countries, particularly in the degree of implementation of endovascular aneurysm repair (EVAR) and levels of vascular surgery centralisation. This study assesses these variations and the impact they have on outcomes. Materials and methods: RAAA repairs from vascular surgical registries in 11 countries, 2010-2013, were investigated. Data were analysed overall, per country, per treatment modality (EVAR or open aortic repair [OAR]), centre volume (quintiles IV), and whether centres were predominantly EVAR (>= 50% of RAAA performed with EVAR [EVAR(p)]) or predominantly OAR [OAR(p)]. Primary outcome was peri-operative mortality. Data are presented as either mean values or percentages with 95% CI within parentheses, and compared with chi-square tests, as well as with adjusted OR. Results: There were 9273 patients included. Mean age was 74.7 (74.5-74.9) years, and 82.7% of patients were men (81.9-83.6). Mean AAA diameter at rupture was 7.6 cm (7.5-7.6). Of these aneurysms, 10.7% (10.0-11.4) were less than 5.5 cm. EVAR was performed in 23.1% (22.3-24.0). There were 6817 procedures performed in OAR(p) centres and 1217 performed in EVAR(p) centres. Overall peri-operative mortality was 28.8% (27.9-29.8). Peri-operative mortality for OAR was 32.1% (31.0-33.2) and for EVAR 17.9% (16.3-19.6), p <.001, and the adjusted OR was 0.38 (0.31-0.47), p <.001. The peri-operative mortality was 23.0% in EVAR(p) centres (20.6-25.4), 29.7% in OAR(p) centres (28.6-30.8), p <.001; adjusted OR = 0.60 (0.46-0.78), p <.001. Perioperative mortality was lower in the highest volume centres (QI > 22 repairs per year), 23.3% (21.2-25.4) than in QII-V, 30.0% (28.9-31.1), p <.001. Peri-operative mortality after OAR was lower in high volume centres compared with the other centres, 25.3% (23.0-27.6) and 34.0% (32.7-35.4), respectively, p <.001. There was no significant difference in peri-operative mortality after EVAR between centres based on volume. Conclusions: Peri-operative mortality is lower in centres with a primary EVAR approach or with high case volume. Most repairs, however, are still performed in low volume centres and in centres with a primary OAR strategy. Reorganisation of acute vascular surgical services may improve outcomes of RAAA repair. (C) 2018 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.
  • Karalis, Elina; Gissler, Mika; Tapper, Anna-Maija; Ulander, Veli-Matti (2016)
    Objective: To evaluate the influence of delivery unit size and on-call staffing in the performance of low-risk deliveries in Finland. Study design: A population-based study of hospital size and level based on Medical Birth Register data. Population was all hospital births in Finland in 2005-2009. Inclusion criteria were singleton births (birth weight 2500 g or more) without major congenital anomalies or birth defects. Additionally, only intrapartum stillbirths were included. Birthweights and maternal background characteristics were adjusted for by logistic regression. Main outcome measures were intrapartum or early neonatal mortality, neonatal asphyxia and newborns' need for intensive care or transfer to other hospital and longer duration of care. On-call arrangements were asked from each of the hospitals. Results: Intrapartum mortality was higher in units where physicians were at home when on-call (OR 1.25; 95% CI 1.02-1.52). A tendency to a higher mortality was also recorded in non-university hospitals (OR 1.18; 95% CI 0.99-1.40). Early neonatal mortality was twofold in units with less than 1000 births annually (OR 2.11; 95% CI 0.97-4.56) and in units where physicians were at home when on-call (OR 1.85; 95% CI 0.91-3.76). These results did not reach statistical significance. No differences between the units were found regarding Apgar scores or umbilical cord pH. Conclusion: The differences in mortality rates between different level hospitals suggest that adverse outcomes during delivery should be studied in detail in relation to hospital characteristics, such as size or level, and more international studies determining obstetric patient safety indicators are required. (C) 2016 Elsevier Ireland Ltd. All rights reserved.
  • Huhtakangas, Juha; Tetri, Sami; Juvela, Seppo; Saloheimo, Pertti; Bode, Michaela K.; Hillbom, Matti (2011)
  • Zhou, P.; Luukkanen, O.; Tokola, T.; Nieminen, Juhana (2008)
  • Taskinen, Seppo; Leskinen, Outi; Lohi, Jouko; Koskenvuo, Minna; Taskinen, Mervi (2019)
    Purpose: To evaluate the association between Wilms tumor histology at diagnosis and the change in Wilms' tumor volume during preoperative chemotherapy. Methods: We included all the 52 patients operated for Wilms tumor at 1988-2015, who had both pathology samples and either CT or MRI-images before and after preoperative chemotherapy, available for reevaluation. Results: The median tumor volume was 586 ml (IQR 323-903) at diagnosis. The median change in tumor volume was -68% (IQR -85 to -40, p <0.001) and the proportion of tumor necrosis 85% (IQR 24-97), after preoperative chemotherapy. There was a correlation between blastemal cell content in prechemotherapy cutting needle biopsy (CNB) sample and the reduction in tumor volume (Rho = -0.452, p = 0.002). High stromal and epithelial cell contents in CNB samples were associated with the lesser change in tumor volume (Rho = 0.279, p = 0.053 and Rho = 0.300, p = 0.038 respectively). Reduction of tumor volume and the proportion of tumor necrosis after chemotherapy were associated (Rho = -0.502, p <0.001). The actual viable tumor volume decreased in median by 97% (IQR 65-100), and the decrease could be seen in all cellular components. In three patients, the tumor volume increased more than 10% during the preoperative chemotherapy. Two of them had anaplastic tumor in the nephrectomy specimen. Conclusion: Wilms tumor total and viable tumor volumes were reduced by 68% and 97% with preoperative chemotherapy, respectively. High proportion of blastemal cells in CNB was associated with greatest decrease in Wilms tumor volume. Increase in tumor volume during preoperative chemotherapy may indicate anaplastic tumor and prolonging of preoperative therapy should be avoided. Type of study: Retrospective review. (C) 2018 Elsevier Inc. All rights reserved.
  • McInerney, Daniel; Barrett, Frank; McRoberts, Ronald E.; Tomppo, Erkki (2018)
  • Luoma, Ville; Vastaranta, Mikko; Eyvindson, Kyle; Kankare, Ville; Saarinen, Ninni; Holopainen, Markus; Hyyppa, Juha (Springer International Publishing AG, 2017)
    Lecture Notes in Geoinformation and Cartography
    Currently the forest sector in Finland is looking towards the next generation's forest resource information systems. Information used in forest planning is currently collected by using an area-based approach (ABA) where airborne laser scanning (ALS) data are used to generalize field-measured inventory attributes over an entire inventory area. Inventories are typically updated at 10-year interval. Thus, one of the key challenges is the age of the inventory information and the cost-benefit trade-off between using the old data and obtaining new data. Prediction of future forest resource information is possible through growth modelling. In this paper, the error sources related to ALS-based forest inventory and the growth models applied in forest planning to update the forest resource information were examined. The error sources included (i) forest inventory, (ii) generation of theoretical stem distribution, and (iii) growth modelling. Error sources (ii) and (iii) stem from the calculations used for forest planning, and were combined in the investigations. Our research area, Evo, is located in southern Finland. In all, 34 forest sample plots (300 m(2)) have been measured twice tree-by-tree. First measurements have been carried out in 2007 and the second measurements in 2014 which leads to 7 year updating period. Respectively, ALS-based forest inventory data were available for 2007. The results showed that prediction of theoretical stem distribution and forest growth modelling affected only slightly to the quality of the predicted stem volume in short-term information update when compared to forest inventory error.
  • Kelaranta, A.; Mäkelä, T.; Kaasalainen, T.; Kortesniemi, M. (2017)
    Purpose: To determine fetal doses in different stages of pregnancy in three common computed tomography (CT) examinations: pulmonary CT angiography, abdomino-pelvic and trauma scan with Monte Carlo (MC) simulations. Methods: An adult female anthropomorphic phantom was scanned with a 64-slice CT using pulmonary angiography, abdomino-pelvic and trauma CT scan protocols. Three different sized gelatin boluses placed on the phantom's abdomen simulated different stages of pregnancy. Intrauterine dose was used as a surrogate to a dose absorbed to the fetus. MC simulations were performed to estimate uterine doses. The simulation dose levels were calibrated with volumetric CT dose index (CTDIvol) measurements and MC simulations in a cylindrical CTDI body phantom and compared with ten point doses measured with metal-oxide-semiconductor field-effect-transistor dosimeters. Intrauterine volumes and uterine walls were segmented and the respective dose volume histograms were calculated. Results: The mean intrauterine doses in different stages of pregnancy varied from 0.04 to 1.04 mGy, from 4.8 to 5.8 mGy, and from 9.8 to 12.6 mGy in the CT scans for pulmonary angiography, abdomino-pelvic and trauma CT scans, respectively. MC simulations showed good correlation with the MOSFET measurement at the measured locations. Conclusions: The three studied examinations provided highly varying fetal doses increasing from sub-mGy level in pulmonary CT angiography to notably higher levels in abdomino-pelvic and trauma scans where the fetus is in the primary exposure range. Volumetric dose distribution offered by MC simulations in an appropriate anthropomorphic phantom provides a comprehensive dose assessment when applied in adjunct to point-dose measurements.
  • Pesonen, Eero; Silvasti-Lundell, Marja; Niemi, Tomi T.; Kivisaari, Riku; Hernesniemi, Juha; Makinen, Marja-Tellervo (2019)
  • Pirinen, Jani; Järvinen, Vesa; Martinez-Majander, Nicolas; Sinisalo, Juha; Pöyhönen, Pauli; Putaala, Jukka (2020)
    BACKGROUND: Ischemic stroke in young individuals often remains cryptogenic. Some of these strokes likely originate from the heart, and atrial fibrosis might be one of the etiological mechanisms. In this pilot study, we investigated whether advanced echocardiography findings of the left atrium (LA) of young cryptogenic stroke patients differ from those of stroke--free controls. METHODS AND RESULTS: We recruited 30 cryptogenic ischemic stroke patients aged 18 to 49 years and 30 age--and sex-matched stroke--free controls among participants of the SECRETO (Searching for Explanations for Cryptogenic Stroke in the Young: Revealing the Etiology, Triggers, and Outcome) study (NCT01934725). We measured basic left ventricular parameters and detailed measures of the LA, including 4--dimensional volumetry, speckle tracking epsilon, strain rate, and LA appendix orifice variation. Data were compared as continuous parameters and by tertiles. Compared with controls, stroke patients had smaller LA reservoir volumes (10.2 [interquartile range, 5.4] versus 13.2 [5.4] mL; P= 0.030) and smaller positive epsilon values (17.8 [8.5] versus 20.8 [10.1]; P= 0.023). In the tertile analysis, stroke patients had significantly lower left atrial appendage orifice variation (3.88 [0.75] versus 4.35 [0.90] mm; P=0.043), lower LA cyclic volume change (9.2 [2.8] versus 12.8 [3.5] mL; P=0.023), and lower LA contraction peak strain rate (-1.8 [0.6] versus -2.3 [0.6]; P=0.021). We found no statistically significant differences in left ventricular measures. CONCLUSIONS: This preliminary comparison suggests altered LA dynamics in young patients with cryptogenic ischemic stroke, and thus that LA wall pathology might contribute to these strokes. Our results await confirmation in a larger sample.
  • Falconer, Christian; Altman, Daniel; Poutakidis, Georgios; Rahkola-Soisalo, Päivi; Mikkola, Tomi; Morcos, Edward (2021)
    Purpose The aim of this study was to compare long-term effects of high-volume surgery at a single-center to multicenter use when using a mesh-capturing device for pelvic organ prolapse (POP) repair. Methods Five years after surgery 101 (88%) at the single center were compared with 164 (81.2%) in the multicenter trial. Outcome measurements included clinical examination, prolapse-specific symptom questionnaires [Pelvic Floor Distress Inventory 20 (PFDI-20), Pelvic Floor Impact Questionnaire-short form (PFIQ-7), Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire (PISQ-12)] and pain estimation by VAS (0-10). Results Optimal apical segment outcome was 95% in the single- compared to 83.3% in the multicenter study (p <0.001). POP recurrence in the anterior and posterior walls (POP-Q, Ba and Bp >= 0) was more common at the multicenter as compared to the single center [(19.8% vs 5.4%) and (26% vs 2.7%), (p <0.001)]. Reoperations for POP and mesh-related complications were more frequent in the multicenter study [31/202 (15.3%) vs 7/116 (6.1%),p <0.001]. Total PFDI-20, PFIQ-7 and PISQ-12 scores were comparable between the cohorts. There were no significant differences in overall pain scores in-between the cohorts during follow-up. At the single center, 1/81 patients (1.2%) had VAS 7/10, i.e. severe pain, as compared to 3/131 (2.3%) in the multicenter study (p = 0.277). Conclusions Despite the high objective and subjective long-term effectiveness of the procedure in both regular use, and at a high-volume center, centralizing the use of a standardized capturing-device guided transvaginal mesh for POP repair reduced secondary interventions by more than half.
  • Ludtka, Christopher; Schwan, Stefan; Friedmann, Andrea; Brehm, Walther; Wiesner, Ingo; Goehre, Felix (2017)
    The primary goal of this study is to clearly define and evaluate new intervertebral disc height parameters in analysing the morphological pathology of disc degeneration for application in damage model and regeneration therapy development, as well as applying traditional variables to 3-D characterization methods. A posterolateral surgical approach was used to induce disc degeneration in an ovine model. At 12-months post-operation, sheep vertebral segments were removed and characterized using micro-CT to evaluate disc height parameters in regard to injury localization. Statistically significant differences between the disc height loss of the left and right side of the disc, consistent with the lateral surgical approach used were seen using the modified average disc height method by Dabbs et al. However, convexity index and the newly proposed Cross Tilt Index did not conclusively demonstrate a difference. Two-dimensional morphological evaluations can be applied in 3-D to provide a more complete picture of disc height loss for injury models. New 3-D parameters that are tailored to the type of surgical approach used should be investigated, with the 9-point system described herein providing a useful basis for derived values. Additionally, the surgical approach chosen when artificially injuring the disc can result in asymmetrical degeneration, as indicated by uneven disc height loss.
  • MRI-GENIE & GISCOME Investigators; Int Stroke Genetics Consortium; Bretzner, Martin; Bonkhoff, Anna K.; Schirmer, Markus D.; Strbian, Daniel; Tatlisumak, Turgut; Worrall, Bradford B. (2021)
    Objective: Neuroimaging measurements of brain structural integrity are thought to be surrogates for brain health, but precise assessments require dedicated advanced image acquisitions. By means of quantitatively describing conventional images, radiomic analyses hold potential for evaluating brain health. We sought to: (1) evaluate radiomics to assess brain structural integrity by predicting white matter hyperintensities burdens (WMH) and (2) uncover associations between predictive radiomic features and clinical phenotypes. Methods: We analyzed a multi-site cohort of 4,163 acute ischemic strokes (AIS) patients with T2-FLAIR MR images with total brain and WMH segmentations. Radiomic features were extracted from normal-appearing brain tissue (brain mask-WMH mask). Radiomics-based prediction of personalized WMH burden was done using ElasticNet linear regression. We built a radiomic signature of WMH with stable selected features predictive of WMH burden and then related this signature to clinical variables using canonical correlation analysis (CCA). Results: Radiomic features were predictive of WMH burden (R-2 = 0.855 +/- 0.011). Seven pairs of canonical variates (CV) significantly correlated the radiomics signature of WMH and clinical traits with respective canonical correlations of 0.81, 0.65, 0.42, 0.24, 0.20, 0.15, and 0.15 (FDR-corrected p-values(CV1-6) < 0.001, p-value(CV7) = 0.012). The clinical CV1 was mainly influenced by age, CV2 by sex, CV3 by history of smoking and diabetes, CV4 by hypertension, CV5 by atrial fibrillation (AF) and diabetes, CV6 by coronary artery disease (CAD), and CV7 by CAD and diabetes. Conclusion: Radiomics extracted from T2-FLAIR images of AIS patients capture microstructural damage of the cerebral parenchyma and correlate with clinical phenotypes, suggesting different radiographical textural abnormalities per cardiovascular risk profile. Further research could evaluate radiomics to predict the progression of WMH and for the follow-up of stroke patients' brain health.