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Periradicular Infiltration for Sciatica

Jaro Karppinen, Antti Malmivaara, Mauno Kurunlahti, Eero Kyllönen, Tuomo Pienimäki, Pentti Nieminen, Arto Ohinmaa, Osmo Tervonen, Heikki Vanharanta
2001 Spine  
Study Design. A randomized, double-blind trial was conducted. Objectives. To test the efficacy of periradicular corticosteroid injection for sciatica. Summary of Background Data. The efficacy of epidural corticosteroids for sciatica is controversial. Periradicular infiltration is a targeted technique, but there are no randomized controlled trials of its efficacy. Methods. In this study 160 consecutive, eligible patients with sciatica who had unilateral symptoms of 1 to 6 months duration, and
more » ... never underwent surgery were randomized for double-blind injection with methylprednisolone bupivacaine combination or saline. Objective and self-reported outcome parameters and costs were recorded at baseline, at 2 and 4 weeks, at 3 and 6 months, and at 1 year. Results. Recovery was better in the steroid group at 2 weeks for leg pain (P ϭ 0.02), straight leg raising (P ϭ 0.03), lumbar flexion (P ϭ 0.05), and patient satisfaction (P ϭ 0.03). Back pain was significantly lower in the saline group at 3 and 6 months (P ϭ 0.03 and 0.002, respectively), and leg pain at 6 months (13.5, P ϭ 0.02). Sick leaves and medical costs were similar for both treatments, except for cost of therapy visits and drugs at 4 weeks, which were in favor of the steroid injection (P ϭ 0.05 and 0.005, respectively). By 1 year, 18 patients in the steroid group and 15 in the saline group underwent surgery. Conclusions. Improvement during the follow-up period was found in both the methylprednisolone and saline groups. The combination of methylprednisolone and bupivacaine seems to have a short-term effect, but at 3 and 6 months, the steroid group seems to experience a "rebound" phenomenon. [
doi:10.1097/00007632-200105010-00015 pmid:11337625 fatcat:pac47kn3wrerrf4zrozcvdsigq

Independent component analysis of nondeterministic fMRI signal sources

Vesa Kiviniemi, Juha-Heikki Kantola, Jukka Jauhiainen, Aapo Hyvärinen, Osmo Tervonen
2003 NeuroImage  
Neuronal activation can be separated from other signal sources of functional magnetic resonance imaging (fMRI) data by using independent component analysis (ICA). Without deliberate neuronal activity of the brain cortex, the fMRI signal is a stochastic sum of various physiological and artifact related signal sources. The ability of spatial-domain ICA to separate spontaneous physiological signal sources was evaluated in 15 anesthetized children known to present prominent vasomotor fluctuations
more » ... the functional cortices. ICA separated multiple clustered signal sources in the primary sensory areas in all of the subjects. The spatial distribution and frequency spectra of the signal sources correspond to the known properties of 0.03-Hz very-low-frequency vasomotor waves in fMRI data. In addition, ICA was able to separate major artery and sagittal sinus related signal sources in each subject. The characteristics of the blood vessel related signal sources were different from the parenchyma sources. ICA analysis of fMRI can be used for both assessing the statistical independence of brain signals and segmenting nondeterministic signal sources for further analysis.
doi:10.1016/s1053-8119(03)00097-1 pmid:12814576 fatcat:haigxfkjcnfvfnsxd7usphahh4

Magnetic resonance imaging-guided biopsies in children

Mika Hirvonen, Juha-Jaakko Sinikumpu, Osmo Tervonen, Roberto Blanco Sequeiros
2021 Acta Radiologica Open  
Magnetic resonance imaging (MRI) is used far less as an imaging-guided method for percutaneous biopsies than computed tomography (CT) and ultrasound (US), despite its imaging benefits, particularly in children. Purpose To evaluate the feasibility, accuracy and safety of MRI-guided biopsies in paediatric patient population. Material and Methods The retrospective study included 57 consecutive paediatric patients (<18 years old). A percutaneous core needle biopsy (PCNB) or trephine biopsy was
more » ... rmed in 53 cases, and an additional fine-needle aspiration biopsy (FNAB) in 26 cases. In 4 cases, a stand-alone FNAB was taken. Biopsies were performed with 0.23 T open and 1.5 T closed MRI scanners. Statistical methods used for confidence intervals and p-values were Wilson score method and chi-square test. Results The overall diagnostic accuracy of histologic biopsy was 0.94, with sensitivity 0.82, specificity 1.00, positive predictive value (PPV) 1.00 and negative predictive value (NPV) 0.92. In histological bone biopsies, diagnostic accuracy was 0.96, with sensitivity 0.86, specificity 1.00, PPV 1.00 and NPV 0.94. The FNAB sample diagnosis was associated with the histological diagnosis in 79% of cases. There were no major primary complications and only a few late complications. After biopsy, 83% of the children were ambulatory in 6 h. Anti-inflammatory drugs and paracetamol provided satisfactory pain relief in 96% of the patients after biopsy. Most outpatients (71%) were discharged from hospital either on the same day or 1 day later. Conclusion MRI is a technically feasible, accurate and safe guidance tool for performing percutaneous biopsies in children.
doi:10.1177/20584601211053846 pmid:34868661 pmcid:PMC8638078 fatcat:lisdekaq4bbrln6ljuymoj2mku

Unjustified CT examinations in young patients

Heljä Oikarinen, Salme Meriläinen, Eija Pääkkö, Ari Karttunen, Miika T. Nieminen, Osmo Tervonen
2009 European Radiology  
doi:10.1007/s00330-008-1256-7 pmid:19156425 fatcat:gyacctwmnzdrfmp2a4mpnnlgiq

Survey of inappropriate use of magnetic resonance imaging

Heljä Oikarinen, Ari Karttunen, Eija Pääkkö, Osmo Tervonen
2013 Insights into Imaging  
Objective There are concerns that not all costly advanced imaging is appropriate. However, studies about the appropriateness of magnetic resonance imaging (MRI) are sparse. The aim of this study was to review various MRI examinations done at a university hospital to determine whether there is inappropriate use. Methods Altogether 150 common MRIs (upper abdomen or liver, lumbar spine, knee, head and head of children performed under anaesthesia, 30 each) were reviewed consecutively. The referrals
more » ... and corresponding patient files were analysed by senior radiologists and the indications of the examinations were compared to the referral criteria. Results Seven per cent of the examinations were deemed inappropriate. All the MRIs of the head done on children were indicated. One to three examinations in all other subgroups were not indicated. The most common appropriate indications were ambiguous hepatic, pancreatic or adrenal lesions, prolonged lower back pain, suspicion of meniscus rupture, brain malignancy and developmental disorder of a child, respectively. Conclusions Although the proportion of inappropriate examinations was not high; financial issues and the growing number of patients referred for MRI are of concern. Education and regular use of up-to-date referral guidelines could help to further improve appropriateness. Main Messages • Seven per cent of the MRI examinations analysed were inappropriate at a university hospital. • Everyday practices of a hospital may contribute to the level of appropriateness. • A survey of indications for previous MRI examinations might be helpful in various institutions.
doi:10.1007/s13244-013-0276-2 pmid:23949843 pmcid:PMC3781254 fatcat:ze5k5zb2vrehjm3ikp2qfaufjq

Cost Effectiveness of Periradicular Infiltration for Sciatica

Jaro Karppinen, Arto Ohinmaa, Antti Malmivaara, Mauno Kurunlahti, Eero Kyllönen, Tuomo Pienimäki, Pentti Nieminen, Osmo Tervonen, Heikki Vanharanta
2001 Spine  
Study Design. A subgroup analysis of a prospective, randomized controlled trial was performed. Objective. To describe the cost effectiveness of periradicular infiltration with steroid in subgroups of patients with sciatica. Summary of Background Data. A recent trial on periradicular infiltration indicated that a methylprednisolonebupivacaine combination had a short-term effect, as compared with that of saline. This report describes the efficacy and cost effectiveness of steroid in subgroups of
more » ... atients with sciatic. Methods. This study involved 160 patients with unilateral sciatica. Outcome assessments were leg pain (100-mm visual analog scale), disability on the Oswestry Low Back Disability Questionnaire, and the Nottingham Health Profile. Data on medical costs and sick leaves also were gathered. Patients were randomized for periradicular infiltration with either methylprednisolone-bupivacaine or saline. The adjusted between-group treatment differences at each follow-up assessment, the number of patients free of leg pain (responders, cutoff 75%), and efficacy by the area-under-the-curve method were calculated. For the cost-effectiveness estimate, the total costs were divided by the number of responders. The rate of operations in different subgroups was evaluated by Kaplan-Meier analysis. Results. In the case of contained herniations, the steroid injection produced significant treatment effects and short-term efficacy in leg pain and in Nottingham Health Profile emotional reactions. For symptomatic lesions at L3-L4 -L5, steroid was superior to saline for leg pain, disability, and straight leg raising in the short term. By 1 year, steroid seemed to have prevented operations for contained herniations, costing $12,666 less per responder in the steroid group (P Ͻ 0.01). For extrusions, steroid seemed to increase the operation rate, and the steroid infiltration was more expensive, costing $4445 per responder (P Ͻ 0.01). Conclusions. In addition to short-term effectiveness for contained herniations and lesions at L3-L4 -L5, steroid treatment also prevented surgery for contained hernia-tions. However, steroid was countereffective for extrusions. The results of the subgroup analyses call for a verification study. [
doi:10.1097/00007632-200112010-00013 pmid:11725240 fatcat:ls54yliwynaa7nepdpk2er4jwu

Persistent default-mode network connectivity during light sedation

Michael D. Greicius, Vesa Kiviniemi, Osmo Tervonen, Vilho Vainionpää, Seppo Alahuhta, Allan L. Reiss, Vinod Menon
2008 Human Brain Mapping  
The default-mode network (DMN) is a set of specific brain regions whose activity, predominant in the resting-state, is attenuated during cognitively demanding, externally-cued tasks. The cognitive correlates of this network have proven difficult to interrogate, but one hypothesis is that regions in the network process episodic memories and semantic knowledge integral to internally-generated mental activity. Here, we compare default-mode functional connectivity in the same group of subjects
more » ... g rest and conscious sedation with midazolam, a state characterized by anterograde amnesia and a reduced level of consciousness. Although the DMN showed functional connectivity during both rest and conscious sedation, a direct comparison found that there was significantly reduced functional connectivity in the posterior cingulate cortex during conscious sedation. These results confirm that lowfrequency oscillations in the DMN persist and remain highly correlated even at reduced levels of consciousness. We hypothesize that focal reductions in DMN connectivity, as shown here in the posterior cingulate cortex, may represent a stable correlate of reduced consciousness. Hum Brain Mapp 29:839-847, 2008. V V C 2008 Wiley-Liss, Inc. in Wiley InterScience (www. interscience.wiley.com). V V C 2008 Wiley-Liss, Inc. r Human Brain Mapping 29:839-847 (2008) r IMAGE ACQUISTION, PROCESSING, AND ANALYSIS Six oblique axial gradient recalled echo planar (EPI) images (7 mm slice thickness) were acquired with the following parameters: repetition time 2,000 ms, echo time 60 ms, flip angle 908, field of view 24 cm, 128 3 128 matrix. r Greicius et al. r r 840 r
doi:10.1002/hbm.20537 pmid:18219620 pmcid:PMC2580760 fatcat:lvek6xl2ubfbjgenhrrashurgi

Interventional and intraoperative MRI at low field scanner – a review

Roberto T. Blanco, Risto Ojala, Juho Kariniemi, Jukka Perälä, Jaakko Niinimäki, Osmo Tervonen
2005 European Journal of Radiology  
Magnetic resonance imaging (MRI) is a cutting edge imaging modality in detecting diseases and pathologic tissue. The superior soft tissue contrast in MRI allows better definition of the pathology. MRI is increasingly used for guiding, monitoring and controlling percutaneous procedures and surgery. The rapid development of interventional techniques in radiology has led to integration of imaging with computers, new therapy devices and operating room like conditions. This has projected as faster
more » ... d more accurate imaging and hence more demanding procedures have been applied to the repertoire of the interventional radiologist. In combining features of various other imaging modalities and adding some more into them, interventional MRI (IMRI) has potential to take further the interventional radiology techniques, minimally invasive therapies and surgery. The term "Interventional MRI" consists in short all those procedures, which are performed under MRI guidance. These procedures can be either percutaneous or open surgical of nature. One of the limiting factors in implementing MRI as guidance modality for interventional procedures has been the fact, that most widely used magnet design, a cylindrical magnet, is not ideal for guiding procedures as it does not allow direct access to the patient. Open, low field scanners usually operating around 0.2 T, offer this feature. Clumsy hardware, bad patient access, slow image update frequency and strong magnetic fields have been other limiting factors for interventional MRI. However, the advantages of MRI as an imaging modality have been so obvious that considerable development has taken place in the 20-year history of MRI. The image quality has become better, ever faster software, new innovative sequences, better MRI hardware and increased computing power have accelerated imaging speed and image quality to a totally new level. Perhaps the most important feature in the recent development has been the introduction of open configuration low field MRI devices in the early 1990s; this enabled direct patient access and utilization of the MRI as an interventional device. This article reviews the current status of interventional and intraoperative MRI with special emphasis in low field surrounding. (R.T. Blanco). guided procedures is minimal invasiveness, which leads to better patient compliance and often better treatment results. The development of ultrasound and CT boosted the use of interventional image guided procedures to a new level. It is possible to do biopsies, aspirations, drainages, palliative tumour therapies and procedures under imaging guidance [1-3]. Magnetic resonance imaging (MRI) was established as a promising diagnostic tool in the beginning of 1980s, it was soon recognized that MRI was a superior diagnostic imaging modality in diagnosing many pathological conditions and 0720-048X/$ -see front matter
doi:10.1016/j.ejrad.2005.03.033 pmid:15908156 fatcat:ov7awupd3zfkjmyevk73vrb5bi

Structure-symptom relationship with wide-area ultrasound scanning of knee osteoarthritis

Jana Podlipská, Juhani M. Koski, Päivi Kaukinen, Marianne Haapea, Osmo Tervonen, Jari P. Arokoski, Simo Saarakkala
2017 Scientific Reports  
The aetiology of knee pain in osteoarthritis (OA) is heterogeneous and its relationship with structural changes and function is unclear. Our goal was to determine the prevalence of wide-area scanned ultrasound-defined knee OA structural features and their association with pain and functional impairment in 79 symptomatic and 63 asymptomatic subjects. All subjects underwent ultrasound knee wide-area scanning and the severity of articular cartilage degeneration, the presence and size of
more » ... , and meniscal extrusion were evaluated. Subjects filled in a self-administrated questionnaire on present knee pain, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) on clinical symptoms and function over the past week. Cartilage changes were the most prevalent followed by lateral meniscal extrusion, osteophytes and medial meniscal extrusion. The global femoral cartilage grade associated strongly with pain and the WOMAC index. Site-specifically, early medial cartilage changes and thinning in sulcus and lateral site were associated with symptoms. The presence of femoral lateral osteophytes was also associated with both outcomes. Using the novel wide-area ultrasound scanning technique, we were able to confirm the negative impact of femoral cartilage OA changes on clinical symptoms. Presence, not necessarily size, of lateral femoral osteophytes was also associated with increased pain and disability.
doi:10.1038/srep44470 pmid:28295049 pmcid:PMC5353612 fatcat:y6q7yw2cknhmngl2wxuirau5q4

Effect of display type, DICOM calibration and room illuminance in bitewing radiographs

Soili Kallio-Pulkkinen, Sisko Huumonen, Marianne Haapea, Esa Liukkonen, Annina Sipola, Osmo Tervonen, Miika T Nieminen
2016 Dentomaxillofacial Radiology  
Cite this article as: Kallio-Pulkkinen S, Huumonen S, Haapea M, Liukkonen E, Sipola A, Tervonen O, et al. Effect of display type, DICOM calibration and room illuminance in bitewing radiographs.  ... 
doi:10.1259/dmfr.20150129 pmid:26234536 pmcid:PMC5083887 fatcat:xizkugxsxrgd3eqaopyoodpc7q

MRI-guided laser ablation of neuroendocrine tumor hepatic metastases

Jukka Perälä, Rauli Klemola, Raija Kallio, Chengli Li, Ilkka Vihriälä, Pasi I Salmela, Osmo Tervonen, Roberto Blanco Sequeiros
2014 Acta Radiologica Short Reports  
Neuroendocrine tumors (NET) represent a therapeutically challenging and heterogeneous group of malignancies occurring throughout the body, but mainly in the gastrointestinal system. Purpose: To describe magnetic resonance imaging (MRI)-guided laser ablation of NET liver metastases and assess its role within the current treatment options and methods. Material and Methods: Two patients with NET tumor hepatic metastases were treated with MRI-guided interstitial laser ablation (LITT). Three tumors
more » ... ere treated. Clinical follow-up time was 10 years. Results: Both patients were successfully treated. There were no local recurrences at the ablation site during the followup. Both patients had survived at 10-year follow-up. One patient is disease-free. Conclusion: MRI-guided laser ablation can be used to treat NET tumor liver metastases but combination therapy and a rigorous follow-up schedule are recommended.
doi:10.1177/2047981613499753 pmid:24778794 pmcid:PMC4001425 fatcat:tmaqzjlgh5ggvk7bazmtppfn7y

Does bone scintigraphy show Modic changes associated with increased bone turnover?

Jyri Järvinen, Jaakko Niinimäki, Jaro Karppinen, Reijo Takalo, Marianne Haapea, Osmo Tervonen
2020 European Journal of Radiology Open  
Our purpose was to evaluate whether Modic changes (MC) revealed in lumbar MRI are associated with increased tracer uptake shown in bone scintigraphy. To our knowledge, this has not previously been studied. We included patients with MC shown in lumbar MRI and bone scintigraphy performed within six months before or after MRI. Exclusion criteria included metastasis and other specific lesions in the area of interest such as discitis, tumors or fractures. We compared the level and type of MC to the
more » ... egree of tracer uptake shown in bone scintigraphy. Tracer uptake was assessed both visually and quantitatively. We calculated the lesion-to-normal-bone ratios between the MC area with increased tracer uptake and the vertebra with normal tracer uptake. We used linear mixed models in statistical analyses. Our study sample consisted of 93 patients (aged 37-86) with 299 MC (28 Type 1 (M1), 50 mixed Type 1/2 (M1/2), 3 mixed Type 1/3 (M1/3), 211 Type 2 (M2), 6 mixed Type 2/3 (M2/3), and 1 Type 3 (M3)). Of all the MC, 26 (93 %) M1, 34 (64 %) in the combined M1/2 and M1/3 group, and 11 (5 %) in the combined M2, M2/3 and M3 group showed increased tracer uptake. The mean lesion-to-normal-bone ratio was higher for lesions with a Type 1 component (M1, M1/2 and M1/3) than for other types, at 1.55 (SD 0.16) for M1; 1.44 (SD 0.21) for combined M1/2 and M1/3; and 1.28 (SD 0.11) for combined M2, M2/3 and M3; p = 0.001). In most cases, MC with a Type 1 component showed increased tracer uptake in bone scintigraphy. This indicates that bone turnover is accelerated in the M1 area.
doi:10.1016/j.ejro.2020.100222 pmid:32071952 pmcid:PMC7013126 fatcat:vehokkjl7vdlhcgt4md7ipwgvq

Magnetic resonance imaging of avascular necrosis of the femoral head: predictive findings of total hip arthroplasty

Matti Väänänen, Osmo Tervonen, Mika T Nevalainen
2021 Acta Radiologica Open  
Avascular osteonecrosis of the femoral head (AVNFH) is an ischemic condition which despite different treatments often leads to collapse of the femoral head and to total hip arthroplasty. However, the magnetic resonance imaging findings predisposing to disease progression and total hip arthroplasty are somewhat elusive. To evaluate the magnetic resonance imaging findings of AVNFH and to assess the patterns of findings which may predict total hip arthroplasty. A retrospective study was conducted
more » ... ith a total of 18 diagnosed AVNFH treated with core decompression combined with intraosseous stem cell treatment. After treatment, magnetic resonance imaging follow-ups were done at three-month and one-year follow-up or until total hip arthroplasty. Association Research Circulation Osseous classification and magnetic resonance imaging findings such as the size and the location of the AVNFH, bone marrow edema in femoral neck, effusion and subchondral fracture were evaluated. Hips advancing to total hip arthroplasty have more often bone marrow edema in femoral neck (90% vs. 0%), adjacent to necrotic lesion (100% vs. 43%) and in acetabulum (90% vs. 14%), but also subchondral fractures (70% vs. 0%), effusion (80% vs. 29%), and synovitis (80% vs. 14,3%). The greater size and the lateral weight-bearing location of the necrotic lesion also predicted future total hip arthroplasty. Hips advancing to total hip arthroplasty have often a combination of pathognomonic AVNFH imaging findings compared to hips not advancing to total hip arthroplasty.
doi:10.1177/20584601211008379 pmid:35140984 pmcid:PMC8819766 fatcat:iukvhmtndjhupm3hvgh43k6w3i

MR-guided bone biopsy: Preliminary report of a new guiding method

Risto Ojala, Roberto Blanco Sequeiros, Rauli Klemola, Erkki Vahala, Lasse Jyrkinen, Osmo Tervonen
2002 Journal of Magnetic Resonance Imaging  
Purpose: To evaluate the feasibility of a new MR compatible optical tracking guided bone biopsy system. Materials and Methods: Wireless optical tracker elements were connected to a bone biopsy set. Biopsies of five different anatomic areas and lesions varying from 9 mm to 40 mm (mean 25 mm) in size, were performed. Results: We were able to perform the biopsies in all cases, and the samples allowed for a pathologic diagnosis. The procedure time was limited to less than 40 minutes, and no
more » ... tions occurred. Conclusion: MR-guided bone biopsy with this new guiding system was a feasible and fast procedure that did not compromise the usability of the bone biopsy set.
doi:10.1002/jmri.10041 pmid:11793461 fatcat:vx23hvmi7bdh7fv2vg2ukh7oc4

A Sliding Time-Window ICA Reveals Spatial Variability of the Default Mode Network in Time

Vesa Kiviniemi, Tapani Vire, Jukka Remes, Ahmed Abou Elseoud, Tuomo Starck, Osmo Tervonen, Juha Nikkinen
2011 Brain Connectivity  
Recent evidence on resting-state networks in functional (connectivity) magnetic resonance imaging (fcMRI) suggests that there may be significant spatial variability of activity foci over time. This study used a sliding time window approach with the spatial domain-independent component analysis (SliTICA) to detect spatial maps of resting-state networks over time. The study hypothesis was that the spatial distribution of a functionally connected network would present marked variability over time.
more » ... The spatial stability of successive sliding-window maps of the default mode network (DMN) from fcMRI data of 12 participants imaged in the resting state was analyzed. Control measures support previous findings on the stability of independent component analysis in measuring sliding-window sources accurately. The spatial similarity of successive DMN maps varied over time at low frequencies and presented a 1/f power spectral pattern. SliTICA maps show marked temporal variation within the DMN; a single voxel was detected inside a group DMN map in maximally 82% of time windows. Mapping of incidental connectivity reveals centrifugally increasing connectivity to the brain cortex outside the DMN core areas. In conclusion, SliTICA shows marked spatial variance of DMN activity in time, which may offer a more comprehensive measurement of the overall functional activity of a network.
doi:10.1089/brain.2011.0036 pmid:22432423 fatcat:ritf62iuvrf2bkaxy7lnkghmwu
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