• The AGES-Reykjavik study atlases: Non-linear multi-spectral template and atlases for studies of the ageing brain

      Forsberg, Lars; Sigurdsson, Sigurdur; Fredriksson, Jesper; Egilsdottir, Asdis; Oskarsdottir, Bryndis; Kjartansson, Olafur; van Buchem, Mark A.; Launer, Lenore J.; Gudnason, Vilmundur; Zijdenbos, Alex; et al. (Elsevier Science, 2017-07)
      Quantitative analyses of brain structures from Magnetic Resonance (MR) image data are often performed using automatic segmentation algorithms. Many of these algorithms rely on templates and atlases in a common coordinate space. Most freely available brain atlases are generated from relatively young individuals and not always derived from well-defined cohort studies. In this paper, we introduce a publicly available multi-spectral template with corresponding tissue probability atlases and regional atlases, optimised to use in studies of ageing cohorts (mean age 75 ± 5 years). Furthermore, we provide validation data from a regional segmentation pipeline to assure the integrity of the dataset.
    • Extramedullary Cavernous Hemangioma with Intradural and Extradural Growth and Clinical Symptoms of Brown-Séquard Syndrome: Case Report and Review of the Literature.

      Baldvinsdóttir, Bryndís; Erlingsdóttir, Gígja; Kjartansson, Ólafur; Ólafsson, Ingvar Hákon; 1 Department of Neurosurgery, Landspítali University Hospital, Reykjavík, Iceland. Electronic address: bryndisbaldvins@gmail.com. 2 Department of Pathology, Landspítali University Hospital, Reykjavík, Iceland. 3 Department of Radiology, Landspítali University Hospital, Reykjavík, Iceland. 4 Department of Neurosurgery, Landspítali University Hospital, Reykjavík, Iceland; Faculty of Medicine, University of Iceland, Reykjavík, Iceland. (Elsevier Science, 2017-02)
      Primary spinal tumors are rare. Symptoms depend on the size and location of the tumor.
    • Fabry Disease in Families With Hypertrophic Cardiomyopathy: Clinical Manifestations in the Classic and Later-Onset Phenotypes.

      Adalsteinsdottir, Berglind; Palsson, Runolfur; Desnick, Robert J; Gardarsdottir, Marianna; Teekakirikul, Polakit; Maron, Martin; Appelbaum, Evan; Neisius, Ulf; Maron, Barry J; Burke, Michael A; et al. (Lippincott Williams & Wilkins, 2017-08)
      The screening of Icelandic patients clinically diagnosed with hypertrophic cardiomyopathy resulted in identification of 8 individuals from 2 families with X-linked Fabry disease (FD) caused by GLA(α-galactosidase A gene) mutations encoding p.D322E (family A) or p.I232T (family B).
    • Incidence of Brain Infarcts, Cognitive Change, and Risk of Dementia in the General Population

      Sigurdsson, Sigurdur; Aspelund, Thor; Kjartansson, Olafur; Gudmundsson, Elias F.; Jonsdottir, Maria K.; Eiriksdottir, Gudny; Jonsson, Palmi V.; van Buchem, Mark A.; Gudnason, Vilmundur; Launer, Lenore J.; et al. (Lippincott Williams & Wilkins, 2017-09)
      BACKGROUND AND PURPOSE: The differentiation of brain infarcts by region is important because their cause and clinical implications may differ. Information on the incidence of these lesions and association with cognition and dementia from longitudinal population studies is scarce. We investigated the incidence of infarcts in cortical, subcortical, cerebellar, and overall brain regions and how prevalent and incident infarcts associate with cognitive change and incident dementia. METHODS: Participants (n=2612, 41% men, mean age 74.6±4.8) underwent brain magnetic resonance imaging for the assessment of infarcts and cognitive testing at baseline and on average 5.2 years later. Incident dementia was assessed according to the international guidelines. RESULTS: Twenty-one percent of the study participants developed new infarcts. The risk of incident infarcts in men was higher than the risk in women (1.8; 95% confidence interval, 1.5-2.3). Persons with both incident and prevalent infarcts showed steeper cognitive decline and had almost double relative risk of incident dementia (1.7; 95% confidence interval, 1.3-2.2) compared with those without infarcts. Persons with new subcortical infarcts had the highest risk of incident dementia compared with those without infarcts (2.6; 95% confidence interval, 1.9-3.4). CONCLUSIONS: Men are at greater risk of developing incident brain infarcts than women. Persons with incident brain infarcts decline faster in cognition and have an increased risk of dementia compared with those free of infarcts. Incident subcortical infarcts contribute more than cortical and cerebellar infarcts to incident dementia which may indicate that infarcts of small vessel disease origin contribute more to the development of dementia than infarcts of embolic origin in larger vessels.
    • Late-life brain volume: a life-course approach. The AGES-Reykjavik study.

      Muller, Majon; Sigurdsson, Sigurdur; Kjartansson, Olafur; Gunnarsdottir, Ingibjorg; Thorsdottir, Inga; Harris, Tamara B; van Buchem, Mark; Gudnason, Vilmundur; Launer, Lenore J; [ 1 ] NIA, Intramural Res Program, Lab Epidemiol & Populat Sci, Bethesda, MD 20892 USA [ 2 ] Vrije Univ Amsterdam, Med Ctr, Dept Internal Med, Amsterdam, Netherlands [ 3 ] Iceland Heart Assoc, Kopavogur, Iceland [ 4 ] Landspitali Univ Hosp, Dept Neurol, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 5 ] Landspitali Univ Hosp, Dept Radiol, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 6 ] Univ Iceland, Unit Nutr Res, Reykjavik, Iceland [ 7 ] Landspitali Univ Hosp, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 8 ] Leiden Univ, Med Ctr, Dept Radiol, Leiden, Netherlands (Elsevier Science Inc, 2016-05)
      The "fetal-origins-of-adult-disease" hypothesis proposes that an unfavorable intrauterine environment, estimated from small birth size, may induce permanent changes in fetal organs, including the brain. These changes in combination with effects of (cardiovascular) exposures during adult life may condition the later risk of brain atrophy. We investigated the combined effect of small birth size and mid-life cardiovascular risk on late-life brain volumes. Archived birth records of weight and height were abstracted for 1348 participants of the age, gene/environment susceptibility-Reykjavik study (RS; 2002-2006) population-based cohort, who participated in the original cohort of the RS (baseline 1967). Mid-life cardiovascular risk factors (CVRF) were collected in the RS. As a part of the late-life age, gene/environment susceptibility-RS examination, a brain magnetic resonance imaging was acquired and from it, volumes of total brain, gray matter, white matter, and white matter lesions were estimated. Adjusting for intracranial volume, demographics, and education showed small birth size (low ponderal index [PI]) and increased mid-life cardiovascular risk had an additive effect on having smaller late-life brain volumes. Compared with the reference group (high PI/absence of mid-life CVRF), participants with lower PI/presence of mid-life CVRF (body mass index >25 kg/m(2), hypertension, diabetes, "ever smokers") had smaller total brain volume later in life; B (95% confidence interval) were -10.9 mL (-21.0 to -0.9), -10.9 mL (-20.4 to -1.4), -20.9 mL (-46.9 to 5.2), and -10.8 mL (-19.3 to -2.2), respectively. These results suggest that exposure to an unfavorable intrauterine environment contributes to the trajectory toward smaller brain volume, adding to the atrophy that may be associated with mid-life cardiovascular risk.
    • A population-based study on epidemiology of intensive care unit treated traumatic brain injury in Iceland.

      Jonsdottir, G M; Lund, S H; Snorradottir, B; Karason, S; Olafsson, I H; Reynisson, K; Mogensen, B; Sigvaldason, K; [ 1 ] Natl Univ Hosp Iceland, Dept Anesthesia & Intens Care Med, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 2 ] Univ Iceland, Ctr Publ Hlth Sci, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 3 ] Univ Iceland, Fac Med, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 4 ] Natl Univ Hosp Iceland, Dept Neurosurg, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 5 ] Natl Univ Hosp Iceland, Dept Radiol, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 6 ] Natl Univ Hosp Iceland, Dept Emergency, Reykjavik, Iceland (Wiley, 2017-04)
      Traumatic brain injury is a worldwide health issue and a significant cause of preventable deaths and disabilities. We aimed to describe population-based data on intensive care treated traumatic brain injury in Iceland over 15 years period.
    • Primary aldosteronism: from case detection to histopathology with up to 6 years of follow-up.

      Jonsdottir, Gudbjörg; Gudmundsson, Jon; Birgisson, Gudjon; Sigurjonsdottir, Helga Agusta; 1Faculty of Medicine, University of Iceland, Reykjavik, Iceland. 2Division of Interventional Radiology, Department of Radiology, Landspitali University Hospital, Reykjavik, Iceland. 3Department of Surgery, Landspitali University Hospital, Reykjavik, Iceland. 4Division of Endocrinology, Department of Medicine, Landspitali University Hospital, Reykjavik, Iceland. (Wiley Periodicals Inc., 2016-11-23)
      The authors aimed to investigate the clinical characteristics, accuracy of diagnostic tests, and long-term outcomes after interventions in patients diagnosed with primary aldosteronism (PA) in Iceland throughout 5 years. A retrospective chart review was performed for all patients diagnosed with PA during the years 2007-2011 at Landspitali Hospital in Iceland, a referral center for the whole country. Workup after detection included salt loading test, positional test, computed tomography, and adrenal vein sampling. Patients with unilateral disease were offered treatment with adrenalectomy. A total of 33 patients were diagnosed with PA during the study period: 17 patients with bilateral disease and 16 with unilateral disease. Results from salt loading test were positive in 90% of patients. In patients with adenoma, 36% were responsive on their positional test and computed tomography scan showed a nodule in 73%. All patients with unilateral disease had a lateralization index ≥3. After surgery, patients had lower systolic blood pressure (P<.001) and number of hypertensive medications (P<.01).
    • Thyrotoxicosis in a 13-year-old girl following pituitary adenectomy for Cushing's disease.

      Sigmarsdottir, Arndis Audur; Olafsson, Ingvar Hakon; Kjartansson, Ólafur; Bjarnason, Ragnar; [ 1 ] Landspitali Univ Hosp, Childrens Hosp Iceland, Dept Pediat, IS-101 Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 2 ] Landspitali Univ Hosp, Dept Neurosurg, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 3 ] Landspitali Univ Hosp, Dept Radiol, Reykjavik, Iceland Show the Organization-Enhanced name(s) [ 4 ] Univ Iceland, Fac Med, Reykjavik, Iceland (Wiley, 2017-08)
      Our objective is to report a case of thyrotoxicosis following pituitary adenectomy for Cushing's disease, the only pediatric case to our knowledge. No thyroid antibodies were detected, and the thyrotoxicosis was successfully treated for 3 months with no relapse after 5 years of follow-up. The cause of thyrotoxicosis remains unknown.
    • The value of magnetic resonance cholangiopancreatography for the exclusion of choledocholithiasis.

      Hjartarson, Jón H; Hannesson, Pétur; Sverrisson, Ingvar; Blöndal, Sigurður; Ívarsson, Bjarki; Björnsson, Einar S; [ 1 ] Natl Univ Hosp Iceland, Dept Gastroenterol & Hepatol, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 2 ] Natl Univ Hosp Iceland, Dept Radiol, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 3 ] Natl Univ Hosp Iceland, Dept Surg, Reykjavik, Iceland   Organization-Enhanced Name(s)      Landspitali National University Hospital [ 4 ] Vastmanlands Hosp, Dept Surg, Vasteras 72189, Sweden [ 5 ] Hosp Heden Horsens, Billeddiagnost Afdeling, Sundvej 30, DK-8700 Horsens, Denmark (Taylor & Francis, 2016-10)
      To investigate the ability of Magnetic resonance cholangiopancreatography (MRCP) to exclude choledocholithiasis (CDL) in symptomatic patients.