342 research outputs found

    Septic arthritis in Iceland 1990–2002: increasing incidence due to iatrogenic infections

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    To access full text version of this article. Please click on the hyperlink "View/Open" at the bottom on this pageOBJECTIVES: To assess the impact of increased number of diagnostic and therapeutic joint procedures on the incidence and type of septic arthritis (SA). METHODS: All cases of SA in Iceland from 1990-2002 were identified by thorough review of the available medical information. The results of synovial fluid cultures from every microbiology department in Iceland were checked and positive culture results reviewed, as well as patient charts with a discharge diagnosis of septic arthritis (International Statistical Classification of Diseases and Related Health Problems (ICD) code M009). RESULTS: A total of 253 cases of SA (69 children and 184 adults) were diagnosed in Iceland in 1990-2002, giving an average incidence of 7.1 cases/100,000 inhabitants. The incidence of SA increased from 4.2 cases/100,000 in 1990 to 11.0 cases/100,000 in 2002. This rise in SA was primarily observed in adults where the incidence rose by 0.61 cases/100,000 per year (p<0.001). SA was iatrogenic in 41.8% of adults and the number of iatrogenic infections increased from 2.8 cases/year in 1990-1994 to 9.0 cases/year in 1998-2002 (p<0.01). The annual number of arthroscopies increased from 430 in 1990-1994 to 2303 in 1998-2002 (p<0.001) and there was a correlation between the total usage of intra-articular drugs in Iceland and the incidence of SA (p<0.01). The frequency of post-arthroscopy SA was 0.14% and post-arthrocentesis SA 0.037%. CONCLUSIONS: The incidence of SA has increased in recent years due to an increased number of arthroscopies and joint injections. Although the frequency of SA per procedure has not changed, these results emphasise the importance of sterile technique and firm indications for joint procedures

    Incidence and management of ectopic pregnancy in Iceland 2000-2009.

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    Efst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn.Utanlegsþykkt getur verið lífshættulegt sjúkdómsástand og meðhöndlun hennar hefur tekið breytingum undanfarna tvo áratugi. Tilgangur rannsóknarinnar var að meta nýgengi og meðhöndlun utanlegsþykktar á Íslandi á áratugnum 2000-2009. Upplýsinga var aflað um öll greind tilvik utanlegsþykktar, meðferðarstað, meðferðartegund og legutíma. Nýgengi var reiknað miðað við fjölda skráðra þungana á almanaksári (n/1000), fjölda kvenna á frjósemisaldri 15-44 ára (n/10000) og í 5 ára aldurshópum. Breytingar á nýgengi, meðferð, aðgerðartækni og legutíma voru kannaðar. Gerður var samanburður á 5 ára tímabilunum 2000-2004 og 2005-2009. Fjöldi greindra utanlegsþykkta á 10 árum var 836, eða 444 árin 2000-2004 og 392 árin 2005-2009. Meðaltal nýgengis var 15,6/1000 skráðar þunganir, eða 12,9/10000 konur á ári. Lækkun var á nýgengi allt tímabilið og milli 5 ára tímabila úr 17,3 í 14,1/1000 þunganir (p=0,003) og 14,1 í 11,7/10000 konur á ári (p<0,01). Skurðaðgerð var fyrsta meðferð hjá 94,9% kvenna, en 3,2% fengu metótrexat og 1,9% biðmeðhöndlun. Hlutfall aðgerða lækkaði úr 98,0% í 91,3% milli 5 ára tímabila samhliða aukinni notkun lyfjameðferðar (0,4% í 6,4%, p<0,0001). Hlutfall kviðsjáraðgerða jókst milli 5 ára tímabila á öllu landinu úr 80,5% í 91,1% (p<0,0001); á Landspítala úr 91,3% í 98,1% (p<0,001) og á sjúkrastofnunum á landsbyggðinni úr 44,0% í 69,3% (p<0,001). Meðallega eftir opna skurðaðgerð var 3,2 dagar en eftir kviðsjáraðgerð 0,9 dagar. Ályktanir: Nýgengi utanlegsþykktar hefur lækkað eins og í nálægum löndum. Meðhöndlun hefur breyst með aukinni notkun kviðsjáraðgerða í stað opinna skurðaðgerða og tilkomu metótrexat-lyfjameðferðar.----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Ectopic pregnancy can be life-threatening. Its treatment has changed radically during the last two decades. The study objective was to evaluate incidence and treatment of ectopic pregnancy in the Icelandic population during the decade 2000-2009. Material and methods: Information was collected about all diagnosed cases, place and method of treatment and admissions. The annual incidence was calculated with reference to number of pregnancies (n/1000), number of women aged 15-44 years (n/10 000) and by 5-year age groups, comparing the periods 2000-2004 and 2005-2009. Results: The number of ectopic pregnancies during these 10 years was 836, or 444 during the years 2000-2004 and 392 during 2005-2009. The average annual incidence was 15.6/1000 pregnancies and 12.9/10 000 women. There was an annual incidence reduction from 17.3 to 14.1/1000 pregnancies (p<0.01) and 14.1 to 11.7/10 000 women (p<0.01). Surgery was the primary treatment for 94.9% of women, methotrexate in 3.2% and expectant management in 1.9%. Surgical management decreased from 98.0% to 91.3% between 5-year periods as medical treatment increased (0.4% to 6.4%; p<0.0001). The proportion of laparoscopic procedures increased from 80.5% to 91.1% (p<0.0001). In the university referral hospital this changed from 91.3% to 98.1% (p<0.001) and in rural hospitals from 44.0% to 69.3% (p<0.001). Mean hospital stay after open surgery was 3.2 days, but 0.9 days after laparoscopy. The incidence reduction of ectopic pregnancy is comparable to the development in neighbouring countries. Management has changed with increased use of laparoscopic surgery, medical and expectant treatment

    Testicular cancer in Iceland 2000-2009: Incidence and survival

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    Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenIntroduction: Survival of patients with testicular germ cell tumours has improved in recent years, mainly due to new modes of chemotherapy. We analyzed incidence, staging and survival of patients diagnosed during the last ten years in Iceland and compared the results to previous studies. Materials and methods: A retrospective study including all Icelandic males diagnosed during 2000-2009. Pathology reports were reviewed and the tumours staged (Boden-Gibb). Overall survival was estimated and seminomas (ST) and non-seminomas (N-ST) compared. Results: 97 males were diagnosed, age-adjusted incidence being 5.9/100.000 males per year. The number of ST and N-ST was almost equal, and the mean age was 35.6 (range; 15-36), but patients with ST were 11.5 years older compared to N-ST. Symptoms were similar in both groups, also tumor size (4.0 cm), which did not change during the study period. Most of the tumours were in stage I, or 78.4%, 13.4% were in stage II og 8.2% in stage III-IV. ST were diagnosed at a significantly lower stage compared to N-ST (91.7 versus 65.3% in stage I; p=0.003). No distant metastases were diagnosed in patients with ST but in 8 patients with N-ST. Four patients died during the study period, two due to N-ST but no patient died because of ST. Five-year survival for the whole patient group was 95.1%. Conclusion: The incidence of testicular carcinoma in Iceland is similar to neighbouring countries and has remained fairly constant for the last two decades. At the same time the number of patients with localized disease (stage I) as well as the size of the tumours has not changed significantly. Survival in Iceland is comparable to the best results reported elsewhere.Inngangur: Á síðustu áratugum hafa lífshorfur sjúklinga með eistnakrabbamein batnað umtalsvert, aðallega vegna tilkomu öflugra krabbameinslyfja. Markmið rannsóknarinnar var að kanna nýgengi, stigun og lífshorfur sjúklinga síðastliðin 10 ár og bera saman við eldri rannsóknir. Efniviður og aðferðir: Rannsóknin er afturskyggn og nær til allra íslenskra karla sem greindust 2000-2009. Farið var yfir meinafræðisvör og æxlin stiguð með kerfi Boden-Gibb. Heildarlífshorfur voru reiknaðar og borin saman sáðfrumukrabbamein (SFK) og ekki-sáðfrumukrabbamein (E-SFK). Niðurstöður: Alls greindust 97 karlar og var aldursstaðlað nýgengi 5,9/100.000 karla á ári. Hlutfall SFK og E-SFK var jafnt, en meðalaldur við greiningu var 35,6 ± 12,0 ár (bil 15-76 ) og var 11,5 árum hærri fyrir SFK en E-SFK. Einkenni og tímalengd einkenna voru hins vegar svipuð, einnig meðalstærð æxlanna (4,0 cm) sem hélst óbreytt á rannsóknartímabilinu. Flest æxlanna voru á stigi I, eða 78,4%, 13,4% á stigi II og 8,2% á stigum III-IV. SFK greindust á marktækt lægri stigum samanborið við E-SFK (91,7 sbr. 65,3% á stigi I; p=0,003). Engin fjarmeinvörp greindust hjá sjúklingum með SFK en hjá átta sjúklingum með E-SFK. Fjórir sjúklingar létust á rannsóknartímabilinu, tveir úr E-SFK en enginn úr SFK. Fimm ára lífshorfur fyrir allan hópinn voru 95,1%. Ályktun: Miðað við nágrannalönd er nýgengi eistnakrabbameins á Íslandi í meðallagi og hefur haldist stöðugt síðustu tvo áratugi. Á sama tímabili hefur hlutfall sjúklinga með staðbundinn sjúkdóm (stig I) lítið breyst og stærð æxlanna sömuleiðis. Lífshorfur hér á landi hafa haldist mjög góðar síðustu áratugi og eru með því hæsta sem þekkist

    Multi-level Trainable Segmentation for Measuring Gestational and Yolk Sacs from Ultrasound Images

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    As a non-hazardous and non-invasive approach to medical diagnostic imaging, ultrasound serves as an ideal candidate for tracking and monitoring pregnancy development. One critical assessment during the first trimester of the pregnancy is the size measurements of the Gestation Sac (GS) and the Yolk Sac (YS) from ultrasound images. Such measurements tend to give a strong indication on the viability of the pregnancy. This paper proposes a novel multi-level trainable segmentation method to achieve three objectives in the following order: (1) segmenting and measuring the GS, (2) automatically identifying the stage of pregnancy, and (3) segmenting and measuring the YS. The first level segmentation employs a trainable segmentation technique based on the histogram of oriented gradients to segment the GS and estimate its size. This is then followed by an automatic identification of the pregnancy stage based on histogram analysis of the content of the segmented GS. The second level segmentation is used after that to detect the YS and extract its relevant size measurements. A trained neural network classifier is employed to perform the segmentation at both levels. The effectiveness of the proposed solution has been evaluated by comparing the automatic size measurements of the GS and YS against the ones obtained gynaecologist. Experimental results on 199 ultrasound images demonstrate the effectiveness of the proposal in producing accurate measurements as well as identifying the correct stage of pregnancy

    Two cases of spontaneous regression of metastasis secondary to renal cell carcinoma

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    Neðst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinn View/OpenSpontaneous regression of metastatic renal cell carcinoma is a rare but well documented event, most often involving pulmonary metastasis. Two cases involving brain and pleural metastasis are presented. In both cases nephrectomy was the only treatment.Sjálfkrafa hvarf meinvarpa nýrnafrumukrabbameins er sjaldséð fyrirbæri. Hér er lýst tveimur tilfellum sem vitað er með vissu að hafi greinst hér á landi. Annars vegar er um að ræða sjálfkrafa hvarf meinvarpa í heila og hins vegar í fleiðru. Báðir sjúklingarnir eru á lífi í dag við góða heilsu, 17 og 11 árum eftir greiningu meinvarpann

    Early outcome in diabetic patients following coronary artery bypass grafting

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    Efst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinnInngangur: Sykursýki er einn af helstu áhættuþáttum kransæðasjúkdóms. Sykursjúkir einstaklingar þróa gjarnan þriggja æða kransæðasjúkdóm sem er í flestum tilvikum meðhöndlaður með kransæðahjáveituaðgerð. Í þessari rannsókn voru könnuð áhrif sykursýki á snemmkomna fylgikvilla kransæðahjáveituaðgerða. Efniviður og aðferðir: Afturskyggn rannsókn á öllum sjúklingum sem gengust undir kransæðahjáveituaðgerð á Landspítala á árunum 2001-2012. Af 1626 sjúklingum voru 261 greindir með sykursýki (16%) og voru þeir bornir saman við 1365 sjúklinga án sykursýki. Forspárþættir fylgikvilla og dauða innan 30 daga voru metnir með aðhvarfsgreiningu. Niðurstöður: Aldur, kyn, útbreiðsla kransæðasjúkdóms og EuroSCORE voru sambærileg í báðum hópum, einnig hlutfall hjáveituaðgerða á sláandi hjarta (21%). Sjúklingar með sykursýki höfðu hærri líkamsþyngdarstuðul (30 á móti 28 kg/m2, p<0,01) og voru oftar með háþrýsting (82% á móti 60%, p<0,001) og gaukulsíunarhraða undir 60 ml/mín/1,73m2 (22% á móti 15%, p=0,01). Auk þess var aðgerðartími þeirra 16 mín lengri (p<0,001). Tíðni djúpra bringubeinssýkinga, heilaáfalls og hjartadreps var sambærileg í báðum hópum. Bráður nýrnaskaði var metinn samkvæmt RIFLE-skilmerkjum og voru sykursýkissjúklingar oftar í RISK-flokki (14% á móti 9%, p=0,02) og FAILURE-flokki (2% á móti 0,5%, p=0,01). Minniháttar fylgikvillar (gáttatif, lungnabólga, þvagfærasýking og yfirborðssýking í skurðsári) voru hins vegar svipaðir í báðum hópum. Dánartíðni innan 30 daga var marktækt hærri hjá sjúklingum með sykursýki, eða 5% borið saman við 2% í viðmiðunarhópi (p=0,01). Sykursýki reyndist ekki sjálfstæður áhættuþættur fyrir dauða innan 30 daga þegar leiðrétt var fyrir öðrum áhættuþáttum með fjölþáttaaðhvarfsgreiningu (OR=1,98, 95% ÖB: 0,72-4,95). Ályktanir: Sjúklingar með sykursýki eru í aukinni áhættu á að fá bráðan nýrnaskaða eftir kransæðahjáveituaðgerð en sykursýki virðist ekki vera sjálfstæður forspárþáttur 30 daga dánartíðni.Introduction: Diabetes is one of the most important risk factors for coronary artery disease. Diabetics often have severe three vessel disease and coronary bypass surgery is in most cases the preferred treatment of choice in these patients. We investigated early surgical complications and outcomes in diabetic patients following isolated CABG in Iceland and compared them to those of non-diabetic patients. Materials and methods: A retrospective study of 1626 consecutive CABG patients operated in Iceland 2001-2012. Diabetic patients were 261 (16%) and were compared to 1365 non-diabetics in terms of patient demographics, operative data, and postoperative outcomes. Logistic regression was used to identify risk factors for major complications and 30-day mortality. Results: The groups were similar in terms of age, gender and Euro-SCORE. Diabetic patients had a higher BMI (30 vs. 28 kg/m2, p<0.001), were more likely to have hypertension (82% vs. 60%, p<0.01) and glomerular filtration rate <60 ml/min/1.73m2 (22% vs. 15%, p=0.01). The rate of deep sternal wound infections, stroke and perioperative myo-cardial infarction was similar in both goups. Acute kidney injury, classified according to the RIFLE-criteria, was higher in diabetic patients, both in the RISK (14% vs. 9%, p=0.02) and FAILURE category (2% vs. 0.5%, p=0.01). Minor complications, (atrial fibrillation, pneumonia, urinary tract infections and superficial wound infections) were similar in both groups. 30-day mortality was 5.0% vs. 2% for diabetics and non-diabetics patients, respectively (p=0.01). Diabetes was not a significant risk factor for 30-day mortality when adjusted for other risk factors with logistic regression (OR=1.98, 95% CI 0.72-4.95). Conclusions: Diabetic patients that underwent CABG more often suffered acute renal injury but diabetes was not an independent prognostic factor of operative mortality

    Outcome of myocardial revascularisation in patients fifty years old and younger.

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    Efst á síðunni er hægt að nálgast greinina í heild sinni með því að smella á hlekkinnInngangur: Meðalaldur þeirra sem gangast undir kransæðahjáveituaðgerð er nálægt sjötugu. Tilgangur rannsóknarinnar var að kanna árangur kransæðahjáveituaðgerða hjá yngri sjúklingum (≤50 ára), meðal annars snemmkomna fylgikvilla, dánartíðni innan 30 daga og langtímalifun. Efniviður og aðferðir: Afturskyggn rannsókn á 1626 sjúklingum sem gengust undir kransæðahjáveituaðgerð á Landspítala 2001-2012. Bornir voru saman 100 sjúklingar 50 ára og yngri og 1526 sjúklinga yfir fimmtugu. Niðurstöður: Hlutfall karla og áhættuþættir kransæðasjúkdóms voru sambærilegar í báðum hópum, einnig útbreiðsla kransæðasjúkdóms og hlutfall sjúklinga með vinstri höfuðstofnsþrengsli. Útstreymisbrot vinstri slegils yngri sjúklinga fyrir aðgerð var marktækt lægra en þeirra eldri (52% á móti 55%, p=0,004), fleiri þeirra höfðu nýlegt hjartadrep fyrir aðgerð (41% á móti 27%, p=0,003) og aðgerð var oftar gerð með flýtingu (58% á móti 45%, p=0,016). Tíðni minniháttar fylgikvilla var lægri hjá yngri sjúklingum (30% á móti 50%, p<0,001), sérstaklega nýtilkomið gáttatif (14% á móti 35%, p<0,001), en blæðing í brjóstholskera á fyrsta sólarhring eftir aðgerð var einnig minni (853 ml á móti 999 ml, p=0,015) og þeir fengu færri einingar af rauðkornaþykkni (1,3 á móti 2,8 ein, p<0,001). Hins vegar reyndist ekki marktækur munur á alvarlegum fylgikvillum (6% á móti 11%, p=0,13) eða dánartíðni innan 30 daga (1% á móti 3%, p=0,5). Legutími yngri sjúklinga var rúmlega tveimur dögum styttri að meðaltali en þeirra eldri (p<0,001). Sjúkdómasértæk lifun var sambærileg fyrir báða aldurshópana en þó sást tilhneiging í átt að betri lifun fyrir yngri sjúklinga (99% á móti 95% fimm ára lifun, p=0,07). Ályktun: Minniháttar fylgikvillar eru sjaldgæfari hjá yngri sjúklingum en þeim eldri, legutími þeirra er styttri og blóðgjafir fátíðari. Einnig virðast veikindi þeirra bera bráðar að. Sjúkdómasértæk lifun yngri sjúklinga virðist ívið betri en eldri sjúklinga.---------------------------------------------------------------------------------------------------------------------------------------------------------Introduction: Most patients that undergo coronary artery bypass grafting (CABG) are around 70 years of age when operated on. We investigated the outcome of CABG in patients 50 years and younger, focusing on early complications, operative mortality and long-term survival. Material and method: A retrospective study on 1626 patients that underwent CABG in Iceland 2001-2012. One hundred patients aged 50 years or younger were compared to 1526 older patients. Results: The male:female ratio, risk factors and extension of coronary artery disease were comparable in both groups, as was the proportion of patients with left main disease. Left ventricular ejection fraction was significantly lower in the younger patients (52 vs. 55%, p=0.004) and more of them had a recent myocardial infarction (41 vs. 27%, p=0.003). Minor complications were less common in the younger group (30 vs. 50%, p<0.001), especially new onset atrial fibrillation (14 vs. 35%, p<0,001). Chest tube bleeding for the first 24 hours postoperatively was also less in the younger group (853 vs. 999 ml, p=0.015) and they received fewer units of packed red cells (1.3 vs. 2.8 units, p<0.001). However, the incidence of major complications was comparable (6 vs. 11%, p=0.13) and the same was true for 30 day mortality (1 vs. 3%, p=0.5). Mean hospital stay was 2 days shorter for younger patients (p<0.001). There was a non-significant trend for improved disease-specific survival for the younger patients, or 99% vs. 95% 5-year survival (p=0.07). Conclusion: In younger patients undergoing CABG minor complications are less common than in older patients, their hospital stay is shorter and transfusions less common. There was also a trend for improved disease specific survival for the younger patients

    Acute kidney injury and outcome following aortic valve replacement for aortic stenosis.

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    To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files. This article is open access.Most studies on acute kidney injury (AKI) following open-heart surgery have focused on short-term outcome following coronary artery bypass grafting. We reviewed the incidence, risk factors and outcome, including long-term survival, of AKI after aortic valve replacement (AVR) in a population-based cohort.A retrospective review of 365 patients who underwent AVR for aortic stenosis during 2002-2011 was made. AKI was defined according to the RIFLE criteria. All patients requiring dialysis were followed up in a centralized registry. Risk factors for AKI were analysed with univariable and multivariable analysis, and survival was graphically presented with the Kaplan-Meier method.The rate of AKI was 82/365 (22.5%); 40, 28 and 14 patients belonging to the Risk, Injury and Failure groups, respectively. Preoperatively, 37 (45.1%) AKI patients had reduced kidney function. Transfusion of red blood cells, obesity and prolonged cardiopulmonary bypass time were independent risk factors for AKI. Acute postoperative dialysis was required in 15 patients (4.1%), and 1 patient developed dialysis-dependent end-stage renal disease. Major postoperative complications were more common in the AKI group (65 vs 22%, P < 0.001). The 30-day mortality rate in the AKI group was 18%, as opposed to 2% in the non-AKI group (P < 0.001), with a 5-year survival rate of 66 vs 87%, respectively (P < 0.001). In multivariable analysis AKI was an independent predictor of operative mortality [odds ratio = 5.89, 95% confidence interval (CI) = 1.99-18.91] but not of long-term survival (hazard ratio = 1.44, 95% CI = 0.86-2.42).More than 1 in 5 patients (22.5%) who underwent AVR developed AKI postoperatively. AKI was associated with higher morbidity and was an independent predictor of operative mortality. However, AKI was not a determinant of long-term survival.Landspitali University Research Fund, University of Iceland Research Fund, Helga Gudmundsdottir and Sigurlidi Kristjansson Memorial Fund

    Post-eruptive volcano inflation following major magma drainage: Interplay between models of viscoelastic response influence and models of magma inflow at Bárðarbunga caldera, Iceland, 2015-2018

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    &amp;lt;p&amp;gt;Unrest at B&amp;amp;#225;r&amp;amp;#240;arbunga after a caldera collapse in 2014-2015 includes elevated seismicity beginning about six months after the eruption ended, including nine Mw&amp;gt;4.5 earthquakes. The earthquakes occurred mostly on the northern and southern parts of a caldera ring fault. Global Navigation Satellite System (GNSS, in particular, Global Positioning System; GPS) and Interferometric Synthetic Aperture Radar (InSAR) geodesy are applied to evaluate the spatial and temporal pattern of ground deformation around B&amp;amp;#225;r&amp;amp;#240;arbunga caldera outside the icecap, in 2015-2018, when deformation rates were relatively steady. The aim is to study the role of viscoelastic relaxation following major magma drainage versus renewed magma inflow as an explanation for the ongoing unrest.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;The largest horizontal velocity is measured at GPS station KISA (3 km from caldera rim), 141 mm/yr in direction N47&amp;lt;sup&amp;gt;o&amp;lt;/sup&amp;gt;E relative to the Eurasian plate in 2015-2018. GPS and InSAR observations show that the velocities decay rapidly outward from the caldera. We correct our observations for Glacial Isostatic Adjustment and plate spreading to extract the deformation related to volcanic activity. After this correction, some GPS sites show subsidence.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;We use a reference Earth model to initially evaluate the contribution of viscoelastic processes to the observed deformation field. We model the deformation within a half-space composed of a 7-km thick elastic layer on top of a viscoelastic layer with a viscosity of 5 x 10&amp;lt;sup&amp;gt;18&amp;lt;/sup&amp;gt; Pa s, considering two co-eruptive contributors to the viscoelastic relaxation: &amp;amp;#8220;non-piston&amp;amp;#8221; magma withdrawal at 10 km depth (modelled as pressure drop in a spherical source) and caldera collapse (modelled as surface unloading). The other model we test is the magma inflow in an elastic half-space. Both the viscoelastic relaxation and magma inflow create horizontal outward movements around the caldera, and uplift at the surface projection of the source center in 2015-2018. Viscoelastic response due to magma withdrawal results in subsidence in the area outside the icecap. Magma inflow creates rapid surface velocity decay as observed.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;We explore further two parameters in the viscoelastic reference model: the viscosity and the &amp;quot;non-piston&amp;quot; magma withdrawal volume. Our comparison between the corrected InSAR velocities and viscoelastic models suggests a viscosity of 2.6&amp;amp;#215;10&amp;lt;sup&amp;gt;18&amp;lt;/sup&amp;gt; Pa s and 0.36 km&amp;lt;sup&amp;gt;3&amp;lt;/sup&amp;gt; of &amp;amp;#8220;non-piston&amp;amp;#8221; magma withdrawal volume, given by the optimal reduced Chi-squared statistic. When the deformation is explained using only magma inflow into a single spherical source (and no viscoelastic response), the optimal model suggests an inflow rate at 1&amp;amp;#215;10&amp;lt;sup&amp;gt;7&amp;lt;/sup&amp;gt; m&amp;lt;sup&amp;gt;3&amp;lt;/sup&amp;gt;/yr at 700 m depth. A magma inflow model with more model parameters is also a possible explanation, including sill inflation at 10 km together with slip on caldera ring faults. Our reference Earth model and the two end-member models suggest that there is a trade-off between the viscoelastic relaxation and the magma inflow, since they produce similar deformation signals outside the icecap. However, to reproduce details of the observed deformation, both processes are required. A viscoelastic-only model cannot fully explain the fast velocity decay away from the caldera, whereas a magma inflow-only model cannot explain the subsidence observed at several locations.&amp;lt;/p&amp;gt; </jats:p
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