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1.
J Intern Med ; 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973251

RESUMEN

BACKGROUND: Spinocerebellar ataxia 4 (SCA4), characterized in 1996, features adult-onset ataxia, polyneuropathy, and linkage to chromosome 16q22.1; its underlying mutation has remained elusive. OBJECTIVE: To explore the radiological and neuropathological abnormalities in the entire neuroaxis in SCA4 and search for its mutation. METHODS: Three Swedish families with undiagnosed ataxia went through clinical, neurophysiological, and neuroimaging tests, including PET studies and genetic investigations. In four cases, neuropathological assessments of the neuroaxis were performed. Genetic testing included short read whole genome sequencing, short tandem repeat analysis with ExpansionHunter de novo, and long read sequencing. RESULTS: Novel features for SCA4 include dysautonomia, motor neuron affection, and abnormal eye movements. We found evidence of anticipation; neuroimaging demonstrated atrophy in the cerebellum, brainstem, and spinal cord. [18F]FDG-PET demonstrated brain hypometabolism and [11C]Flumazenil-PET reduced binding in several brain lobes, insula, thalamus, hypothalamus, and cerebellum. Moderate to severe loss of Purkinje cells in the cerebellum and of motor neurons in the anterior horns of the spinal cord along with pronounced degeneration of posterior tracts was also found. Intranuclear, mainly neuronal, inclusions positive for p62 and ubiquitin were sparse but widespread in the CNS. This finding prompted assessment for nucleotide expansions. A polyglycine stretch encoding GGC expansions in the last exon of the zink finger homeobox 3 gene was identified segregating with disease and not found in 1000 controls. CONCLUSIONS: SCA4 is a neurodegenerative disease caused by a novel GGC expansion in the coding region of ZFHX3, and its spectrum is expanded to include dysautonomia and neuromuscular manifestations.

2.
Eur J Radiol ; 177: 111557, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38954912

RESUMEN

PURPOSE: When treating Lung Cancer, it is necessary to identify early treatment failure to enable timely therapeutic adjustments. The Aim of this study was to investigate whether changes in tumor diffusion during treatment with chemotherapy and bevacizumab could serve as a predictor of treatment failure. MATERIAL AND METHODS: A prospective single-arm, open-label, clinical trial was conducted between September 2014 and December 2020, enrolling patients with stage IV non-small cell lung cancer (NSCLC). The patients were treated with chemotherapy-antiangiogenic combination. Diffusion weighted magnetic resonance imaging (DW-MRI) was performed at baseline, two, four, and sixteen weeks after initiating treatment. The differences in apparent diffusion coefficient (ADC) values between pre- and post-treatment MRIs were recorded as Delta values (ΔADC). We assessed whether ΔADC could serve as a prognostic biomarker for overall survival (OS), with a five year follow up. RESULTS: 18 patients were included in the final analysis. Patients with a ΔADC value ≥ -3 demonstrated a significantly longer OS with an HR of 0.12 (95 % CI; 0.03- 0.61; p = 0.003) The median OS in patients with a ΔADC value ≥ -3 was 18 months, (95 % C.I; 7-46) compared to 7 months (95 % C.I; 5-9) in those with a ΔADC value < -3. CONCLUSION: Our findings suggest that early changes in tumor ADC values, may be indicative of a longer OS. Therefore, DW-MRI could serve as an early biomarker for assessing treatment response in patients receiving chemotherapy combined with antiangiogenic therapy.


Asunto(s)
Inhibidores de la Angiogénesis , Bevacizumab , Carcinoma de Pulmón de Células no Pequeñas , Imagen de Difusión por Resonancia Magnética , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Femenino , Masculino , Estudios Prospectivos , Persona de Mediana Edad , Anciano , Pronóstico , Bevacizumab/uso terapéutico , Inhibidores de la Angiogénesis/uso terapéutico , Estadificación de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
3.
NEJM Evid ; 3(8): EVIDoa2400056, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39023393

RESUMEN

BACKGROUND: Operative treatment is widely used for acute proximal hamstring avulsions, but its effectiveness compared with that of nonoperative treatment has not been shown in randomized trials. METHODS: In this noninferiority trial at 10 centers in Sweden and Norway, we enrolled patients 30 to 70 years of age with a proximal hamstring avulsion in a randomized trial and a parallel observational cohort. Treatments were operative reinsertion of the tendons or nonoperative management. The primary end point was the Perth Hamstring Assessment Tool (PHAT) at 2 years of follow-up. Secondary outcomes included scores on the Lower Extremity Functional Scale (LEFS). RESULTS: A total of 119 patients were enrolled in the randomized trial and 97 patients in the observational cohort. In the per-protocol analysis of the randomized trial, the mean (±standard deviation) PHAT scores were 79.9±19.5 and 78.5±19.4 in the operative and nonoperative groups, respectively (PHAT scores range from 0 to 100, with higher scores indicating higher function). The prespecified noninferiority limit of 10 points was not crossed (mean difference, -1.2; 95% confidence interval [CI], -8.6 to 6.2; P=0.009 for noninferiority). Analyses of secondary outcomes, including a mean difference in the LEFS score of -1.6 (95% CI, -5.2 to 2.0), aligned with the primary outcome. The observed numbers of adverse events in the randomized trial were nine in the operative group versus three in the nonoperative group (odds ratio, 0.3; 95% CI, 0.1 to 1.2). In the analysis of the observational cohort, the mean PHAT score difference between the nonoperative and operative treatment groups was -2.6 (95% CI, -9.9 to 4.6). CONCLUSIONS: In patients 30 to 70 years of age with proximal hamstring avulsions, nonoperative treatment was noninferior to operative treatment. (Funded by Afa Försäkring and others; ClinicalTrials.gov number, NCT03311997.).


Asunto(s)
Músculos Isquiosurales , Traumatismos de los Tendones , Humanos , Persona de Mediana Edad , Masculino , Femenino , Anciano , Músculos Isquiosurales/lesiones , Adulto , Traumatismos de los Tendones/terapia , Traumatismos de los Tendones/rehabilitación , Traumatismos de los Tendones/cirugía , Resultado del Tratamiento , Noruega , Suecia
4.
Pain Rep ; 9(2): e1148, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38500565

RESUMEN

Introduction: In many pain conditions, there is lingering pain despite healed tissue damage. Our previous study shows that individuals who underwent surgery for lumbar disk herniation (LDH) during adolescence have worse health, more pain, and increased disk degeneration mean 13 years after surgery compared with controls. It is unclear if walking patterns segregate surgically treated LDH adolescents and controls at mean 13-year follow-up. Objectives: Here, we analyzed the relationship between gait, back morphology and other health outcomes in a cohort of individuals treated surgically because of lumbar disk herniation compared with controls. Methods: We analyzed gait during a walking paradigm, back morphology at the site of surgery, and standardized health outcomes, among individuals who received surgery for LDH as adolescents, "cases" (n = 23), compared with "controls" (n = 23). Results: There were gait differences in head (P = 0.021) and trunk angle (P = 0.021) between cases and controls in a direction where cases exhibited a posture associated with sickness. The gait variance was explained by subjective pain and exercise habits rather than objective disk degeneration. Conclusion: Over a decade after surgery for LDH during adolescence, health among cases is worse compared with controls. The head and trunk angles differ between cases and controls, indicating that the residual pain lingers and may cause changes in movement patterns long after a painful episode in early life. Gait may be a useful target for understanding maintenance of pain and disability among individuals treated surgically for LDH during adolescence.

5.
Acta Orthop ; 95: 92-98, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38305634

RESUMEN

BACKGROUND AND PURPOSE: Adults treated surgically for lumbar disc herniation in adolescence have a higher degree of lumbar disc degeneration than controls. We aimed to establish whether the degree of lumbar degeneration differs at diagnosis or at follow-up between surgically and non-surgically treated individuals. METHODS: We identified individuals with a lumbar disc herniation in adolescence diagnosed with magnetic resonance imaging (MRI) and contacted them for follow-up MRI. Lumbar degeneration was assessed according to Pfirrmann, Modic, and total end plate score (TEP score). Patient-reported outcome measures at follow-up comprised the Oswestry Disability Index (ODI), EQ-5D-3-level version, 36-Item Short Form Health Survey (SF-36), and Visual Analogue Scale (VAS) for back and leg pain. Fisher's exact test, Mann-Whitney U tests, Wilcoxon tests, and logistic regression were used for statistical analysis. RESULTS: MRIs were available at diagnosis and after a mean of 11.9 years in 17 surgically treated individuals and 14 non-surgically treated individuals. Lumbar degeneration was similar at diagnosis (P = 0.2) and at follow-up, with the exception of higher TEP scores in surgically treated individuals at levels L4-L5 and L5-S1 at follow-up (P ≤ 0.03), but this difference did not remain after adjustment for age and sex (P ≥ 0.8). There were no significant differences in patient-reported outcome measures between the groups at follow-up (all P ≥ 0.2). CONCLUSION: Adolescents with a lumbar disc herniation have, irrespective of treatment, a similar degree of lumbar degeneration at the time of diagnosis, and similar lumbar degeneration and patient-reported outcomes at long-term follow-up.


Asunto(s)
Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral , Adulto , Adolescente , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico , Desplazamiento del Disco Intervertebral/cirugía , Estudios de Seguimiento , Resultado del Tratamiento , Calidad de Vida , Degeneración del Disco Intervertebral/cirugía , Estudios de Casos y Controles , Vértebras Lumbares/cirugía
6.
J Orthop Surg Res ; 18(1): 114, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36797740

RESUMEN

BACKGROUND: Proximal hamstring tendon avulsions (PHAs) may be treated nonoperatively or operatively. Little is known about the result of the injury, and its treatment, on the quality and function of the hamstring muscle after healing and rehabilitation. We hypothesized that the injured leg would have greater fatty infiltration and atrophy than the uninjured leg at follow-up and that these findings would correlate to muscle weakness. METHODS: In a cross-sectional cohort study, 48 patients treated for PHA, either operatively or nonoperatively, were re-examined 2-11 years post-treatment. We measured muscle strength with isokinetic strength tests, and muscle volume and fatty infiltration with MRI. Primary outcomes were hamstring muscle quality, quantified by outlining the cross-sectional area slice-by-slice, and the degree of fatty infiltration estimated using the Goutallier grading method. Secondary outcome was concentric isokinetic hamstring muscle strength measured using BioDex at 60°/sec and tendon attachment assessed on MRI. Comparisons with the outcomes of the uninjured leg were made. RESULTS: The total hamstring muscle volume was on average reduced by 9% (SD ± 11%, p < 0.001) compared to that of the uninjured leg. Fatty infiltration was significantly more severe in the injured hamstrings than in the uninjured hamstrings (p < 0.001). This was also true when only analyzing operatively treated patients. The reduction in muscle volume and increase in fatty infiltration correlated significantly (r = 0.357, p = 0.013), and there was also a statistically significant correlation with muscle atrophy and reduction in isokinetic strength (r = 494, p < 0.001). CONCLUSION: PHA injuries result in fatty infiltration and muscle atrophy and the muscle quality impairment correlates with residual muscle weakness.


Asunto(s)
Músculos Isquiosurales , Tendones Isquiotibiales , Traumatismos de los Tendones , Humanos , Músculos Isquiosurales/diagnóstico por imagen , Músculo Esquelético/fisiología , Estudios de Seguimiento , Pierna , Estudios Transversales , Tendones , Atrofia Muscular/diagnóstico por imagen , Atrofia Muscular/etiología , Traumatismos de los Tendones/cirugía , Debilidad Muscular , Fuerza Muscular/fisiología
7.
Bone Joint J ; 104-B(12): 1343-1351, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36453045

RESUMEN

AIMS: The aims of this study were first, to determine if adding fusion to a decompression of the lumbar spine for spinal stenosis decreases the rate of radiological restenosis and/or proximal adjacent level stenosis two years after surgery, and second, to evaluate the change in vertebral slip two years after surgery with and without fusion. METHODS: The Swedish Spinal Stenosis Study (SSSS) was conducted between 2006 and 2012 at five public and two private hospitals. Six centres participated in this two-year MRI follow-up. We randomized 222 patients with central lumbar spinal stenosis at one or two adjacent levels into two groups, decompression alone and decompression with fusion. The presence or absence of a preoperative spondylolisthesis was noted. A new stenosis on two-year MRI was used as the primary outcome, defined as a dural sac cross-sectional area ≤ 75 mm2 at the operated level (restenosis) and/or at the level above (proximal adjacent level stenosis). RESULTS: A total of 211 patients underwent surgery at a mean age of 66 years (69% female): 103 were treated by decompression with fusion and 108 by decompression alone. A two-year MRI was available for 176 (90%) of the eligible patients. A new stenosis at the operated and/or adjacent level occurred more frequently after decompression and fusion than after decompression alone (47% vs 29%; p = 0.020). The difference remained in the subgroup with a preoperative spondylolisthesis, (48% vs 24%; p = 0.020), but did not reach significance for those without (45% vs 35%; p = 0.488). Proximal adjacent level stenosis was more common after fusion than after decompression alone (44% vs 17%; p < 0.001). Restenosis at the operated level was less frequent after fusion than decompression alone (4% vs 14%; p = 0.036). Vertebral slip increased by 1.1 mm after decompression alone, regardless of whether a preoperative spondylolisthesis was present or not. CONCLUSION: Adding fusion to a decompression increased the rate of new stenosis on two-year MRI, even when a spondylolisthesis was present preoperatively. This supports decompression alone as the preferred method of surgery for spinal stenosis, whether or not a degenerative spondylolisthesis is present preoperatively.Cite this article: Bone Joint J 2022;104-B(12):1343-1351.


Asunto(s)
Estenosis Espinal , Espondilolistesis , Humanos , Femenino , Anciano , Masculino , Estenosis Espinal/diagnóstico por imagen , Estenosis Espinal/cirugía , Constricción Patológica , Estudios de Seguimiento , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/cirugía , Imagen por Resonancia Magnética , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Descompresión
8.
Arch Orthop Trauma Surg ; 142(8): 1985-1994, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34585303

RESUMEN

INTRODUCTION: Discerning whether range of motion (ROM) is restricted by morphology or other pain sources is challenging in patients with femoroacetabular impingement syndrome (FAIS). Computed tomography (CT) motion simulation provides a hypothetical ROM based on morphology. This study aimed to explore associations between ROM measured using CT motion simulation and maximum passive ROM measured clinically using three dimensional (3D) motion analysis in patients with FAIS, prior to and post arthroscopic hip surgery. MATERIALS AND METHODS: Eight males with FAIS (in total 12 hip joints) were included in this explorative feasibility study. Participants were examined using CT according to a low-dose protocol prior to and 7-months post arthroscopic surgery. Software was used to simulate at which ROM the impingement would occur. With the hip in 90 degrees' flexion, maximum passive range of internal hip rotation, and maximum passive internal hip rotation coupled with adduction was examined clinically using 3D motion analysis pre- and postoperatively. Spearman rank correlation coefficients and linear regressions examined associations between methods. RESULTS: Preoperatively, the correlation between maximum internal hip rotation measured using CT motion simulation and 3D motion analysis was strong (r = 0.71, p = 0.009). Linear regressions demonstrated that maximal internal rotation measured using CT motion simulation was predominantly larger than when measured using 3D motion analysis. Postoperatively, and when maximum internal rotation was coupled with adduction, no correlations were found between the two methods. CONCLUSIONS: The hypothetical morphology restricted ROM is larger than clinically assessed pain restricted ROM, both prior to and post hip arthroscopy. These findings suggest that ROM is restricted by pain rather than mechanical, morphology-based impingement in individuals with FAIS.


Asunto(s)
Pinzamiento Femoroacetabular , Artroscopía , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/cirugía , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/cirugía , Humanos , Masculino , Dolor , Rango del Movimiento Articular
9.
Artículo en Inglés | MEDLINE | ID: mdl-34841186

RESUMEN

BACKGROUND: The purpose of this study was to describe the prevalence of lumbar spine degeneration in adult individuals who had undergone lumbar disc herniation surgery during adolescence. METHODS: Twenty-three individuals who had been surgically treated for lumbar disc herniation as adolescents (≤18 years of age) participated in this study at a mean of 13.8 years (range, 8.6 to 20.4 years) after the surgery; they were matched for age and sex to 23 controls without any known previous disc herniation or spinal surgery. Magnetic resonance imaging included sagittal T1-weighted, T2-weighted, and short tau inversion recovery (STIR) sequences of the lumbar spine. Disc degeneration was assessed with the Pfirrmann grading system. Changes in the vertebral end plate and body were assessed according to Modic changes and total end plate (TEP) score. Patient-reported outcome measures included the Oswestry Disability Index, a visual analog scale (VAS) for leg and back pain, the EuroQol-5 Dimension-3 Level (EQ-5D-3L) questionnaire, and the mental and physical component summary scores of the Short Form (SF)-36. Statistical analyses were made with the chi-square test and the Welch-Satterthwaite t test. RESULTS: Compared with the controls, the cases that underwent surgery had a higher prevalence of the following: severe degeneration according to the Pfirrmann grading system at the L4-L5 (p = 0.007) and L5-S1 (p = 0.002) levels, Modic changes at the L4-L5 (p = 0.022) and L5-S1 (p = 0.026) levels, and a TEP score of ≥6 at the L5-S1 level (p = 0.001). The surgical cases had a significantly worse patient-reported outcome compared with the controls (all p ≤ 0.010), with the exception of the VAS for leg pain (p = 0.093) and the mental component summary score of the SF-36 (p = 0.844). CONCLUSIONS: Lumbar disc herniation surgery that was performed during adolescence was associated with more frequent lumbar spine degeneration and lower health-related quality of life in adulthood when compared with the control group. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

11.
Magn Reson Med ; 86(4): 2025-2033, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34056750

RESUMEN

PURPOSE: Tensor-valued diffusion encoding provides more specific information than conventional diffusion-weighted imaging (DWI), but has mainly been applied in neuroimaging studies. This study aimed to assess its potential for the imaging of prostate cancer (PCa). METHODS: Seventeen patients with histologically proven PCa were enrolled. DWI of the prostate was performed with linear and spherical tensor encoding using a maximal b-value of 1.5 ms/µm2 and a voxel size of 3 × 3 × 4 mm3 . The gamma-distribution model was used to estimate the mean diffusivity (MD), the isotropic kurtosis (MKI ), and the anisotropic kurtosis (MKA ). Regions of interest were placed in MR-defined cancerous tissues, as well as in apparently healthy tissues in the peripheral and transitional zones (PZs and TZs). RESULTS: DWI with linear and spherical encoding yielded different image contrasts at high b-values, which enabled the estimation of MKA and MKI . Compared with healthy tissue (PZs and TZs combined) the cancers displayed a significantly lower MD (P < .05), higher MKI (P < 10-5 ), and lower MKA (P < .05). Compared with the TZ, tissue in the PZ showed lower MD (P < 10-3 ) and higher MKA (P < 10-3 ). No significant differences were found between cancers of different Gleason scores, possibly because of the limited sample size. CONCLUSION: Tensor-valued diffusion encoding enabled mapping of MKA and MKI in the prostate. The elevated MKI in PCa compared with normal tissues suggests an elevated heterogeneity in the cancers. Increased in-plane resolution could improve tumor delineation in future studies.


Asunto(s)
Próstata , Neoplasias de la Próstata , Anisotropía , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora , Humanos , Masculino , Clasificación del Tumor , Próstata/diagnóstico por imagen , Neoplasias de la Próstata/diagnóstico por imagen
12.
Phys Imaging Radiat Oncol ; 17: 117-123, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33898790

RESUMEN

BACKGROUND AND PURPOSE: In locally advanced prostate cancer (PC), androgen deprivation therapy (ADT) in combination with whole prostate radiotherapy (RT) is the standard treatment. ADT affects the prostate as well as the tumour on multiparametric magnetic resonance imaging (MRI) with decreased PC conspicuity and impaired localisation of the prostate lesion. Image texture analysis has been suggested to be of aid in separating tumour from normal tissue. The aim of the study was to investigate the impact of ADT on baseline defined MRI features in prostate cancer with the goal to investigate if it might be of use in radiotherapy planning. MATERIALS AND METHODS: Fifty PC patients were included. Multiparametric MRI was performed before, and three months after ADT. At baseline, a tumour volume was delineated on apparent diffusion coefficient (ADC) maps with suspected tumour content and a reference volume in normal prostatic tissue. These volumes were transferred to MRIs after ADT and were analysed with first-order -and invariant Haralick -features. RESULTS: At baseline, the median value and several of the invariant Haralick features of ADC, showed a significant difference between tumour and reference volumes. After ADT, only ADC median value could significantly differentiate the two volumes. CONCLUSIONS: Invariant Haralick -features could not distinguish between baseline MRI defined PC and normal tissue after ADT. First-order median value remained significantly different in tumour and reference volumes after ADT, but the difference was less pronounced than before ADT.

15.
Diagn Cytopathol ; 49(1): 46-53, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32786062

RESUMEN

BACKGROUND: Clear-cell chondrosarcomas (CCCSs) constitute a very rare subtype of chondrosarcoma. CCCS may radiologically mimic chondroblastoma, and given the difference in surgical approach, it is important to distinguish these two entities preoperatively. DESIGN: Using the institutional digital records, we identified histologically verified CCCS between 1996 and 2013, where preoperative fine-needle aspiration (FNA) cytology was available. Clinical characteristics were categorized and described, and FNAs were reviewed by a panel of senior cytopathologists. In addition, corresponding radiological imaging was reviewed by senior radiologists, and a literature review on CCCS and chondroblastoma was conducted. RESULTS: A total of seven CCCS FNAs were identified from six patients. The cytomorphology showed low to intermediate cellular smears of clusters and single round or oval tumor cells. Tumor cells had rounded (sometimes binucleated) nuclei with limited pleomorphism and rich vacuolated cytoplasm. Chondroid background matrix was always found. While CCCS patients had a significantly higher age at diagnosis compared to chondroblastoma, no age cut-off would distinctly separate the two. CONCLUSIONS: CCCS has distinguished cytomorphological features on FNA smears. CCCS should be considered as a possible differential diagnosis in adults (>25 years) with a radiological suspicion of chondroblastoma. Since radiology and patient age cannot conclusively distinguish CCCS from chondroblastoma, FNA may prove an important tool for correct preoperative diagnosis of CCCS.


Asunto(s)
Neoplasias Óseas/diagnóstico , Neoplasias Óseas/patología , Condrosarcoma/diagnóstico , Condrosarcoma/patología , Adolescente , Adulto , Biopsia con Aguja Fina/métodos , Condroblastoma/diagnóstico , Condroblastoma/patología , Citodiagnóstico/métodos , Demografía/métodos , Diagnóstico Diferencial , Femenino , Humanos , Masculino
16.
Magn Reson Med ; 85(3): 1468-1480, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33090529

RESUMEN

PURPOSE: To describe a new method for encoding chemical shift using asymmetric readout waveforms that enables more SNR-efficient fat/water imaging. METHODS: Chemical shift was encoded using asymmetric readout waveforms, rather than conventional shifted trapezoid readouts. Two asymmetric waveforms are described: a triangle and a spline. The concept was applied to a fat/water separated RARE sequence to increase sampling efficiency. The benefits were investigated through comparisons to shifted trapezoid readouts. Using asymmetric readout waveforms, the scan time was either shortened or maintained to increase SNR. A matched in-phase waveform is also described that aims to improve the SNR transfer function of the fat and water estimates. The sequence was demonstrated for cervical spine, musculoskeletal (MSK), and optic nerve applications at 3T and compared with conventional shifted readouts. RESULTS: By removing sequence dead times, scan times were shortened by 30% with maintained SNR. The shorter echo spacing also reduced T2 blurring. Maintaining the scan times and using asymmetric readout waveforms achieved an SNR improvement in agreement with the prolonged sampling duration. CONCLUSIONS: Asymmetric readout waveforms offer an additional degree of freedom in pulse sequence designs where chemical shift encoding is desired. This can be used to significantly shorten scan times or to increase SNR with maintained scan time.


Asunto(s)
Imagen por Resonancia Magnética , Nervio Óptico
17.
Ugeskr Laeger ; 182(42)2020 10 12.
Artículo en Danés | MEDLINE | ID: mdl-33046199

RESUMEN

Infection has been proposed as a cause of back pain in individuals with Modic changes. This review summarises the knowledge on this topic in Scandinavia. A Norwegian randomized controlled trial could not replicate results in favor of antibiotic treatment for such patients. A Danish study demonstrated that patients with low back pain and Modic changes had similar physical disability-scores and less sick leave due to back pain than individuals without Modic changes at long-term follow-up (>10 years). A Swedish study displayed equal bacterial presence in discs of patients operated for lumbar disc herniation and in control patients, indicating that the presence of bacteria is caused by contamination during the surgical procedure and is not related to back pain.


Asunto(s)
Antibacterianos , Desplazamiento del Disco Intervertebral , Antibacterianos/uso terapéutico , Dolor de Espalda/tratamiento farmacológico , Humanos , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/tratamiento farmacológico , Vértebras Lumbares/diagnóstico por imagen , Imagen por Resonancia Magnética , Países Escandinavos y Nórdicos , Resultado del Tratamiento
18.
Lakartidningen ; 1172020 09 23.
Artículo en Sueco | MEDLINE | ID: mdl-32969480

RESUMEN

This report is based on results from three research groups in Sweden (Fritzell et al), Denmark (Udby et al), and Norway (Bråten et al). The groups have conducted studies published in international journals in 2019 [8-10]. The results complement each other and strongly suggest that antibiotics, in the absence of clear signs of a clinically relevant infection (discitis/spondylitis), should not be used for back pain with or without leg pain. The Swedish study showed that bacteria found in the disc/vertebra during surgery are very likely due to contamination [8], the Danish study showed that patients with Modic Changes (MC) on MR in the long term were not associated with more back pain or functional impairment than in patients without MC [9], and the Norwegian study showed that antibiotics for residual back pain after previous disc herniation had no better clinical effect than placebo [10]. Antibiotic resistance is one of the biggest threats to public health today and in the future.


Asunto(s)
Desplazamiento del Disco Intervertebral , Dolor de la Región Lumbar , Antibacterianos/uso terapéutico , Dolor de Espalda/tratamiento farmacológico , Humanos , Pierna , Vértebras Lumbares , Noruega , Suecia/epidemiología
19.
Eur Spine J ; 29(1): 196-197, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31664566

RESUMEN

Unfortunately, the 5th author name was incorrectly published in the original paper. The complete correct name is given below.

20.
Eur Spine J ; 28(12): 2981-2989, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31576463

RESUMEN

PURPOSE: To compare bacterial findings in pain-generating degenerated discs in adults operated on for lumbar disc herniation (LDH), and mostly also suffering from low back pain (LBP), with findings in adolescent patients with non-degenerated non-pain-generating discs operated on for scoliosis, and to evaluate associations with Modic signs on magnetic resonance imaging (MRI). Cutibacterium acnes (Propionibacterium acnes) has been found in painful degenerated discs, why it has been suggested treating patients with LDH/LBP with antibiotics. As multidrug-resistant bacteria are a worldwide concern, new indications for using antibiotics should be based on solid scientific evidence. METHODS: Between 2015 and 2017, 40 adults with LDH/LBP (median age 43, IQR 33-49) and 20 control patients with scoliosis (median age 17, IQR 15-20) underwent surgery at seven Swedish hospitals. Samples were cultured from skin, surgical wound, discs and vertebrae. Genetic relatedness of C. acnes isolates was investigated using single-nucleotide polymorphism analysis. DNA samples collected from discs/vertebrae were analysed using 16S rRNA-based PCR sequencing. MRI findings were assessed for Modic changes. RESULTS: No bacterial growth was found in 6/40 (15%) LDH patients, compared with 3/20 (15%) scoliosis patients. Most positive samples in both groups were isolated from the skin and then from subcutis or deep within the wound. Of the four disc and vertebral samples from each of the 60 patients, 235/240 (98%) were DNA negative by bacterial PCR. A single species, C. acnes, was found exclusively in the disc/vertebra from one patient in each group. In the LDH group, 29/40 (72%) patients had at least one sample with growth of C. acnes, compared to 14/20 (70%) in the scoliosis group. Bacterial findings and Modic changes were not associated. CONCLUSIONS: Cutibacterium acnes found in discs and vertebrae during surgery for disc herniation in adults with degenerated discs may be caused by contamination, as findings in this group were similar to findings in a control group of young patients with scoliosis and non-degenerated discs. Furthermore, such findings were almost always combined with bacterial findings on the skin and/or in the wound. There was no association between preoperative Modic changes and bacterial findings. Antibiotic treatment of lumbar disc herniation with sciatica and/or low back pain, without signs of clinical discitis/spondylitis, should be seriously questioned. These slides can be retrieved under Electronic Supplementary Material.


Asunto(s)
Desplazamiento del Disco Intervertebral , Dolor de la Región Lumbar , Vértebras Lumbares/cirugía , Adolescente , Adulto , Humanos , Desplazamiento del Disco Intervertebral/complicaciones , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Desplazamiento del Disco Intervertebral/epidemiología , Desplazamiento del Disco Intervertebral/cirugía , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/epidemiología , Dolor de la Región Lumbar/etiología , Imagen por Resonancia Magnética , Persona de Mediana Edad , Propionibacterium acnes/aislamiento & purificación , Escoliosis/diagnóstico por imagen , Escoliosis/epidemiología , Escoliosis/cirugía , Piel/microbiología , Herida Quirúrgica/microbiología , Adulto Joven
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