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PURPOSE: To evaluate the effectiveness of microfragmented adipose tissue (MFAT) for pain relief and improved joint functionality in osteoarthritis (OA) of the knee in a randomized controlled clinical trial with 1-year follow-up. METHODS: Seventy-five patients were stratified by baseline pain level and randomized to 1 of 3 treatment groups: MFAT, corticosteroid (CS), or saline control (C) injection. Patients 18 years of age or older, diagnosed with symptomatic OA of the knee, with radiographic evidence of OA of the knee and a visual analog pain scale score of 3 of 10 or greater were included. Patients were excluded if they had any previous intra-articular knee injection, current knee ligamentous instability, or an allergy to lidocaine/corticosteroid. The visual analog pain scale, Western Ontario and McMaster Universities Osteoarthritis Index, and the Knee Injury and Osteoarthritis Outcome score (KOOS) were recorded preprocedure and at 2 weeks, 6 weeks, 3 and 6 months, and 1-year follow-up. RESULTS: MFAT demonstrated consistent and statistically significant improvements across all primary outcome measures for joint pain and functionality compared with C. For MFAT, there was a significant improvement over baseline at each follow-up, with median (95% confidence interval) KOOS Pain score changes of 18.1 (11.1-26.4) at week 2 to 27.8 (19.4-37.5) at 1 year. For CS, the median KOOS pain score reached a maximum of 22.2 (15.3-30.6) at week 2, only to level off to 13.9 (-2.8 to 29.2), a level not statistically different from baseline, at 1 year. The median changes for C hovered around 6 to 11 points, with statistically significant improvements over baseline indicating a placebo effect. Similar trends were seen for the Western Ontario and McMaster Universities Osteoarthritis Index Pain score and VAS Pain score. CONCLUSIONS: In this study, MFAT demonstrated a clinically significant improvement in primary outcome scores compared with the C group, whereas the CS group only showed statistically significant improvement compared with the C group at 2 and 6 weeks. This finding indicates that MFAT may be a viable alternative treatment for patients with OA of the knee who fall into the orthopaedic treatment gap. LEVEL OF EVIDENCE: Level II, partially blinded, randomized controlled clinical trial.
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Accurate delineation of gross tumor volumes remains a barrier to radiotherapy dose escalation and boost dosing in the treatment of solid tumors, such as prostate cancer. Magnetic resonance imaging (MRI) of tumor targets has the power to enable focal dose boosting, particularly when combined with technological advances such as MRI-linear accelerator. Fibroblast activation protein (FAP) is overexpressed in stromal components of >90% of epithelial carcinomas. Herein, the authors compare targeted MRI of prostate specific membrane antigen (PSMA) with FAP in the delineation of orthotopic prostate tumors. Control, FAP, and PSMA-targeting iron oxide nanoparticles were prepared with modification of a lymphotropic MRI agent (FerroTrace, Ferronova). Mice with orthotopic LNCaP tumors underwent MRI 24 h after intravenous injection of nanoparticles. FAP and PSMA nanoparticles produced contrast enhancement on MRI when compared to control nanoparticles. FAP-targeted MRI increased the proportion of tumor contrast-enhancing black pixels by 13%, compared to PSMA. Analysis of changes in R2 values between healthy prostates and LNCaP tumors indicated an increase in contrast-enhancing pixels in the tumor border of 15% when targeting FAP, compared to PSMA. This study demonstrates the preclinical feasibility of PSMA and FAP-targeted MRI which can enable targeted image-guided focal therapy of localized prostate cancer.
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Nanopartículas , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Próstata , Imageamento por Ressonância Magnética , FibroblastosRESUMO
BACKGROUND: Increasing access and better allocation of organs in the field of transplantation is a critical problem in clinical care. Limitations exist in accurately predicting allograft discard. Potential exists for machine learning to provide a balanced assessment of the potential for an organ to be used in a transplantation procedure. METHODS: We accessed and utilized all available deceased donor United Network for Organ Sharing data from 1987 to 2020. With these data, we evaluated the performance of multiple machine learning methods for predicting organ use. The machine learning methods trialed included XGBoost, random forest, Naïve Bayes (NB), logistic regression, and fully connected feedforward neural network classifier methods. The top two methods, XGBoost and random forest, were fully developed using 10-fold cross-validation and Bayesian optimization of hyperparameters. RESULTS: The top performing model at predicting liver organ use was an XGBoost model which achieved an AUC-ROC of .925, an AUC-PR of .868, and an F1 statistic of .756. The top performing model for predicting kidney organ use classification was an XGBoost model which achieved an AUC-ROC of .952, and AUC-PR of .883, and an F1 statistic of .786. CONCLUSIONS: The XGBoost method demonstrated a significant improvement in predicting donor allograft discard for both kidney and livers in solid organ transplantation procedures. Machine learning methods are well suited to be incorporated into the clinical workflow; they can provide robust quantitative predictions and meaningful data insights for clinician consideration and transplantation decision-making.
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Aprendizado de Máquina , Doadores de Tecidos , Humanos , Teorema de Bayes , Modelos LogísticosRESUMO
BACKGROUND: Gastrectomy with extended (D2) lymphadenectomy is considered standard of care for gastric cancer to provide the best possible outcomes and pathologic staging. However, D2 gastrectomy is a technically demanding operation and reported to be associated with increased complications and mortality. Application of sentinel lymph node (SLN) concept in gastric cancer has the potential to reduce patient morbidity; however, SLN techniques are not established for gastrectomy, in part due to lack of practical tracers. An effective and convenient tracer with enhanced SLN accumulation is critically needed. METHODS: Mannose-labelled magnetic tracer 'FerroTrace' and fluorescent dye indocyanine green (ICG) were injected laparoscopically into the stomach submucosa of 8 healthy swine under general anaesthesia. Intraoperative fluorescence imaging was used to highlight draining lymphatic pathways containing ICG, while preoperative T2-weighted MRI and ex vivo magnetometer probe measurements were used to identify nodes containing FerroTrace. Lymphadenectomy was performed either robotically (n = 2) or via laparotomy (n = 6). RESULTS: Mixing ICG and FerroTrace ensured concurrence of fluorescent and magnetic signals in SLNs. An initial trial with robotic dissection removed all magnetic LNs (n = 4). In the subsequent laparotomy study that targeted all ICG-LNs based on intraoperative fluorescence imaging, dissection removed an average of 4.7 ± 1.2 fluorescent, and 2.0 ± 1.3 magnetic LNs per animal. Both MRI and magnetometer detected 100% of SLNs (n = 7). FerroTrace demonstrated high specificity to SLNs, which contained 76 ± 30% of total lymphotropic iron, and 88 ± 20 % of the overall magnetometer signal. CONCLUSIONS: Through utilisation of this dual tracer approach, SLNs were identified via preoperative MRI, visualised intraoperatively with fluorescence imaging, and confirmed with a magnetometer. This combination pairs the sensitivity of ICG with SLN-specific FerroTrace and can be used for reliable SLN detection in gastric cancer, with potential applications in neoadjuvant therapy.
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Nanopartículas de Magnetita , Linfonodo Sentinela , Neoplasias Gástricas , Animais , Suínos , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/cirurgia , Linfonodo Sentinela/patologia , Verde de Indocianina , Biópsia de Linfonodo Sentinela/métodos , Manose , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Corantes , Excisão de Linfonodo , Corantes Fluorescentes , Linfonodos/diagnóstico por imagem , Linfonodos/cirurgia , Linfonodos/patologiaRESUMO
Sentinel lymph node biopsy in cancers of the head and neck offers demonstrated clinical and diagnostic value, but adoption is limited by concerns about the detrimental consequence to survival of false negative results in a highly curable setting. The aim of this study was to demonstrate potential to overcome this via application of a novel mannose-labeled magnetic iron oxide tracer. In a large animal model, preoperative imaging and intraoperative magnetometer detection were used to identify magnetic lymph nodes. Iron quantification mapped the distribution of tracer within lymphatic levels. Over a 4-week test period, uptake of magnetic tracer in lymph nodes increased in a linear-like fashion, with a substantial percentage of accumulated iron (83%) being retained in the sentinel node. This result indicates a high affinity of mannose-labeled particles to the sentinel node, while providing a means for the magnetometer probe to indicate node status based on intraoperative signal.
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Nanopartículas de Magnetita , Linfonodo Sentinela , Animais , Ferro , Linfonodos , Fenômenos Magnéticos , Manose , Linfonodo Sentinela/diagnóstico por imagem , Linfonodo Sentinela/cirurgia , Biópsia de Linfonodo Sentinela/métodosRESUMO
OBJECTIVE: To determine if the evaluation of the fetal ventricular system and hindbrain herniation (HBH) is associated with motor outcome at birth in prenatally repaired open neural tube defect (NTD). METHODS: Retrospective cohort study of 47 patients with NTD who underwent prenatal repair (17 fetoscopic; 30 open-hysterotomy). At referral and 6 weeks postoperatively, the degree of HBH, ventricular atrial widths and ventricular volume were evaluated by MRI. Head circumference and ventricular atrial widths were measured on ultrasound at referral and during the last ultrasound before delivery. Anatomic level of the lesion (LL) was determined based on the upper bony spinal defect detected by ultrasound. We considered the functional level as worse than anatomical level at birth when the motor level was equal or worse than the anatomical LL. RESULTS: 26% (12/47) of the cases showed worse functional level than anatomical level at birth. Having a HBH below C1 at the time of referral was associated with a worse functional level than anatomical level at birth (OR = 9.7, CI95 [2.2-42.8], p < 0.01). None of the other brain parameters showed a significant association with motor outcomes at birth. CONCLUSIONS: HBH below C1 before surgery was associated with a worse functional level than anatomical level at birth.
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Estado Funcional , Hidrocefalia/complicações , Defeitos do Tubo Neural/cirurgia , Rombencéfalo/anormalidades , Adulto , Estudos de Coortes , Feminino , Humanos , Hidrocefalia/epidemiologia , Hidrocefalia/cirurgia , Recém-Nascido , Imageamento por Ressonância Magnética/métodos , Defeitos do Tubo Neural/complicações , Defeitos do Tubo Neural/epidemiologia , Procedimentos Neurocirúrgicos/efeitos adversos , Procedimentos Neurocirúrgicos/métodos , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Gravidez , Cuidado Pré-Natal/métodos , Estudos Retrospectivos , Rombencéfalo/lesões , Rombencéfalo/cirurgia , Texas/epidemiologiaRESUMO
INTRODUCTION: Paramedian forehead flap for nasal reconstruction may involve the use of a structural graft. The authors hypothesized that the use of structural grafts with paramedian forehead flap is associated with an increased risk of 30-day complications. METHODS: This is a retrospective study of the American College of Surgeon (ACS) National Surgical Quality Improvement Program (NSQIP). We identified all patients undergoing paramedian forehead flap reconstruction from 2007 through 2018 using Current Procedural Terminology code 15731. Patients who had structural graft harvested at the time of paramedian forehead flap were identified using Current Procedural Terminology codes. Groups were defined based on the use of structural grafts. Propensity score matching was performed using preoperative and intraoperative characteristics to produce matched cohorts. The authors further stratified individual graft types to identify differential risks associated with each. Logistic regression was then used to determine whether the use of structural grafts was associated with increased risk for 30-day complications. RESULTS: The authors identified 1198 patients with paramedian forehead flap reconstruction, of whom 325 (27.1%) required structural grafts. Propensity score matching 1:1 yielded 247 patients in each of the matched cohorts. Overall 30-day complications (4.5% versus 5.3%), wound related complications (3.2% versus 4.1%), systemic complications (1.2% versus 2%), unplanned reoperation (6.5% versus 3.2%), and unplanned readmission (6.6% versus 10.2%) were similar between the 2 groups (Pâ>â0.05). Subgroup analysis of different graft types showed that costochondral graft was associated with increased wound related complications (0.9% versus 8.3%, Pâ=â0.03). The odds of having wound related complications with the use of costochondral graft was ORâ=â5.3, CIâ=â1.5-18.8, Pâ=â0.02. CONCLUSIONS: Although the use of structural grafts does not increase risk of overall 30-day complications, there is an increased risk of wound related complications associated with the use of costochondral and rib grafts.
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Testa , Rinoplastia , Testa/cirurgia , Humanos , Morbidade , Estudos Retrospectivos , Retalhos CirúrgicosRESUMO
In this report, the authors describe a child presenting at 6 months old with a rapidly expanding extracranial left temporal mass concerning for malignancy. The mass was successfully treated at 16 months with radical surgical excision. The patient was found to have a tenosynovial giant cell tumor, diffuse type, completely encased by the temporalis muscle. To our knowledge, this is the first report of a case of diffuse type tenosynovial giant cell tumor in the temporalis muscle, without articular involvement, presenting in an infant.
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Tumor de Células Gigantes de Bainha Tendinosa/cirurgia , Feminino , Tumor de Células Gigantes de Bainha Tendinosa/complicações , Humanos , Lactente , Sinovite Pigmentada Vilonodular/etiologiaRESUMO
BACKGROUND: Therapeutic hypothermia is the standard-of-care treatment for infants diagnosed with moderate-to-severe hypoxic-ischemic encephalopathy (HIE). MRI for assessing brain injury is usually performed after hypothermia because of logistical challenges in bringing acutely sick infants receiving hypothermia from the neonatal intensive care unit (NICU) to the MRI suite. Perhaps examining and comparing early cerebral oxygen metabolism disturbances to those after rewarming will lead to a better understanding of the mechanisms of brain injury in HIE and the effects of therapeutic hypothermia. OBJECTIVE: The objectives were to assess the feasibility of performing a novel T2-relaxation under spin tagging (TRUST) MRI technique to measure venous oxygen saturation very early in the time course of treatment, 18-24 h after the initiation of therapeutic hypothermia, to provide a framework to measure neonatal cerebral oxygen metabolism noninvasively, and to compare parameters between early and post-hypothermia MRIs. MATERIALS AND METHODS: Early (18-24 h after initiating hypothermia) MRIs were performed during hypothermia treatment in nine infants with HIE (six with moderate and three with severe HIE). Six infants subsequently had an MRI after hypothermia. Mean values of cerebral blood flow, oxygen extraction fraction, and cerebral metabolic rate of oxygen from MRIs during hypothermia were compared between infants with moderate and severe HIE; and in those with moderate HIE, we compared cerebral oxygen metabolism parameters between MRIs performed during and after hypothermia. RESULTS: During the initial hypothermia MRI at 23.5±5.2 h after birth, infants with severe HIE had lower oxygen extraction fraction (P=0.04) and cerebral metabolic rate of oxygen (P=0.03) and a trend toward lower cerebral blood flow (P=0.33) compared to infants with moderate HIE. In infants with moderate HIE, cerebral blood flow decreased and oxygen extraction fraction increased between MRIs during and after hypothermia (although not significantly); cerebral metabolic rate of oxygen (P=0.93) was not different. CONCLUSION: Early MRIs were technically feasible while maintaining hypothermic goal temperatures in infants with HIE. Cerebral oxygen metabolism early during hypothermia is more disturbed in severe HIE. In infants with moderate HIE, cerebral blood flow decreased and oxygen extraction fraction increased between early and post-hypothermia scans. A comparison of cerebral oxygen metabolism parameters between early and post-hypothermia MRIs might improve our understanding of the evolution of HIE and the benefits of hypothermia. This approach could guide the use of adjunctive neuroprotective strategies in affected infants.
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Hipotermia Induzida , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/terapia , Imageamento por Ressonância Magnética/métodos , Circulação Cerebrovascular , Estudos de Viabilidade , Feminino , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Oxigênio/metabolismoRESUMO
BACKGROUND: Hypoxic-ischemic encephalopathy (HIE) remains a significant cause of mortality and neurodevelopmental impairment despite treatment with therapeutic hypothermia. Magnetic resonance H1-spectroscopy measures concentrations of cerebral metabolites to detect derangements in aerobic metabolism. OBJECTIVE: We assessed MR spectroscopy in neonates with HIE within 18-24 h of initiating therapeutic hypothermia and at 5-6 days post therapeutic hypothermia. MATERIALS AND METHODS: Eleven neonates with HIE underwent MR spectroscopy of the basal ganglia and white matter. We compared metabolite concentrations during therapeutic hypothermia and post-therapeutic hypothermia and between moderate and severe HIE. RESULTS: During therapeutic hypothermia, neonates with severe HIE had decreased basal ganglia N-acetylaspartate (NAA; 0.62±0.08 vs. 0.72±0.05; P=0.02), NAA + N-acetylaspartylglutamate (NAAG; 0.66±0.11 vs. 0.77±0.06; P=0.05), glycerophosphorylcholine + phosphatidylcholine (GPC+PCh; 0.28±0.05 vs. 0.38±0.06; P=0.02) and decreased white matter GPC+PCh (0.35±0.13 vs. 0.48±0.04; P=0.02) compared to neonates with moderate HIE. For all subjects, basal ganglia NAA decreased (-0.08±0.07; P=0.01), whereas white matter GPC+PCh increased (0.03±0.04; P=0.04) from therapeutic hypothermia MRI to post-therapeutic-hypothermia MRI. All metabolite values are expressed in mmol/L. CONCLUSION: Decreased NAA and GPC+PCh were associated with greater HIE severity and could distinguish neonates who might benefit most from targeted additional neuroprotective therapies.
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Hipotermia Induzida , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Hipóxia-Isquemia Encefálica/terapia , Espectroscopia de Prótons por Ressonância Magnética , Biomarcadores/metabolismo , Feminino , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Recém-Nascido , Imageamento por Ressonância Magnética , MasculinoRESUMO
OBJECTIVE: The calculation of HCO3 and base excess in current blood gas analysis is based on the Siggaard-Andersen equation. One of the constants in this equation is dependent on the known buffering capacity of hemoglobin A. We sought to investigate differences in buffering capacity between adult hemoglobin A and fetal hemoglobin F as a potential explanation for the observed poor correlation between calculated base excess in umbilical cord blood and newborn outcomes. Such differences would influence a key constant in the Van Slyke/Siggaard-Andersen equation used to calculate HCO3 and base excess and could be an explanation of these observations. STUDY DESIGN: This was a prospective observational study. We analyzed umbilical cord blood bicarbonate levels both as calculated values from a traditional blood gas analyzer and as measured values in 20 women giving birth at term. Since the calculated value is dependent upon the concentration and known buffering capacity of hemoglobin A, significant differences in these two analyses would imply differences in the buffering capacity of hemoglobins A and F. RESULTS: The mean calculated HCO3 value was 25 mEq/L (25.3 ± 1.9) compared with a mean measured value of 25 mEq/L (24.6 ± 1.7) over a range of pH levels of 7.16 to 7.42. This difference was not significant (p = 0.07). CONCLUSION: The buffering capacity of hemoglobin F, for clinical purposes, is not different than that of hemoglobin A and is not an explanation for the recognized poor correlation between base excess and neonatal outcome.
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Bicarbonatos/sangue , Gasometria , Sangue Fetal/química , Hemoglobina Fetal , Nomogramas , Equilíbrio Ácido-Base , Desequilíbrio Ácido-Base , Adulto , Feminino , Hemoglobina A , Humanos , Concentração de Íons de Hidrogênio , Gravidez , Estudos ProspectivosRESUMO
BACKGROUND: Congenital Zika virus (ZIKV) infection can be detected in both the presence and absence of microcephaly and manifests as a number of signs and symptoms that are detected clinically and by neuroimaging. However, to date, qualitative and quantitative measures for the purpose of diagnosis and prognosis are limited. OBJECTIVES: Main objectives of this study conducted on fetuses and infants with confirmed congenital Zika virus infection and detected brain abnormalities were (1) to assess the prevalence of microcephaly and the frequency of the anomalies that include a detailed description based on ultrasound and magnetic resonance imaging in fetuses and ultrasound, magnetic resonance imaging, and computed tomography imaging postnatally, (2) to provide quantitative measures of fetal and infant brain findings by magnetic resonance imaging with the use of volumetric analyses and diffusion-weighted imaging, and (3) to obtain additional information from placental and fetal histopathologic assessments and postnatal clinical evaluations. STUDY DESIGN: This is a longitudinal cohort study of Zika virus-infected pregnancies from a single institution in Colombia. Clinical and imaging findings of patients with laboratory-confirmed Zika virus infection and fetal brain anomalies were the focus of this study. Patients underwent monthly fetal ultrasound scans, neurosonography, and a fetal magnetic resonance imaging. Postnatally, infant brain assessment was offered by the use of ultrasound imaging, magnetic resonance imaging, and/or computed tomography. Fetal head circumference measurements were compared with different reference ranges with <2 or <3 standard deviations below the mean for the diagnosis of microcephaly. Fetal and infant magnetic resonance imaging images were processed to obtain a quantitative brain volumetric assessment. Diffusion weighted imaging sequences were processed to assess brain microstructure. Anthropometric, neurologic, auditory, and visual assessments were performed postnatally. Histopathologic assessment was included if patients opted for pregnancy termination. RESULTS: All women (n=214) had been referred for Zika virus symptoms during pregnancy that affected themselves or their partners or if fetal anomalies that are compatible with congenital Zika virus syndrome were detected. A total of 12 pregnant patients with laboratory confirmation of Zika virus infection were diagnosed with fetal brain malformations. Most common findings that were assessed by prenatal and postnatal imaging were brain volume loss (92%), calcifications (92%), callosal anomalies (100%), cortical malformations (89%), and ventriculomegaly (92%). Results from fetal brain volumetric assessment by magnetic resonance imaging showed that 1 of the most common findings associated with microcephaly was reduced supratentorial brain parenchyma and increased subarachnoid cerebrospinal fluid. Diffusion weighted imaging analyses of apparent diffusion coefficient values showed microstructural changes. Microcephaly was present in 33.3-58.3% of the cases at referral and was present at delivery in 55.6-77.8% of cases. At birth, most of the affected neonates (55.6-77.8%) had head circumference measurements >3 standard deviations below the mean. Postnatal imaging studies confirmed brain malformations that were detected prenatally. Auditory screening results were normal in 2 cases that were assessed. Visual screening showed different anomalies in 2 of the 3 cases that were examined. Pathologic results that were obtained from 2 of the 3 cases who opted for termination showed similar signs of abnormalities in the central nervous system and placental analyses, including brain microcalcifications. CONCLUSION: Congenital microcephaly is not an optimal screening method for congenital Zika virus syndrome, because it may not accompany other evident and preceding brain findings; microcephaly could be an endpoint of the disease that results from progressive changes that are related to brain volume loss. Long-term studies are needed to understand the clinical and developmental relevance of these findings.
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Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Complicações Infecciosas na Gravidez/epidemiologia , Infecção por Zika virus/epidemiologia , Adolescente , Adulto , Calcinose/diagnóstico por imagem , Líquido Cefalorraquidiano/fisiologia , Estudos de Coortes , Colômbia/epidemiologia , Diagnóstico por Imagem , Potenciais Evocados Auditivos , Potenciais Evocados Visuais , Feminino , Humanos , Hidrocefalia/diagnóstico por imagem , Recém-Nascido , Estudos Longitudinais , Microcefalia/virologia , Gravidez , Espaço Subaracnóideo/fisiologia , Adulto Jovem , Infecção por Zika virus/congênitoRESUMO
A cross-validation analysis evaluating computer model prediction accuracy for a priori planning magnetic resonance-guided laser-induced thermal therapy (MRgLITT) procedures in treating focal diseased brain tissue is presented. Two mathematical models are considered. (1) A spectral element discretisation of the transient Pennes bioheat transfer equation is implemented to predict the laser-induced heating in perfused tissue. (2) A closed-form algorithm for predicting the steady-state heat transfer from a linear superposition of analytic point source heating functions is also considered. Prediction accuracy is retrospectively evaluated via leave-one-out cross-validation (LOOCV). Modelling predictions are quantitatively evaluated in terms of a Dice similarity coefficient (DSC) between the simulated thermal dose and thermal dose information contained within N = 22 MR thermometry datasets. During LOOCV analysis, the transient model's DSC mean and median are 0.7323 and 0.8001 respectively, with 15 of 22 DSC values exceeding the success criterion of DSC ≥ 0.7. The steady-state model's DSC mean and median are 0.6431 and 0.6770 respectively, with 10 of 22 passing. A one-sample, one-sided Wilcoxon signed-rank test indicates that the transient finite element method model achieves the prediction success criteria, DSC ≥ 0.7, at a statistically significant level.
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Hipertermia Induzida/métodos , Terapia a Laser , Modelos Biológicos , Algoritmos , Calibragem , Humanos , Imageamento por Ressonância Magnética , Planejamento de Assistência ao PacienteRESUMO
PURPOSE: A common source of loss in signal-to-noise ratio (SNR) in fetal brain magnetic resonance spectroscopy (MRS) is from fetal movement and temporal magnetic field drift. We investigated the feasibility of using constructive averaging strategies for improving the spectral quality and recovering the SNR loss from these effects. MATERIALS AND METHODS: Eight fetuses, between 20 3/7 and 38 2/7 weeks' gestation, were scanned with MRS at 1.5 T. Single-voxel point-resolved spectroscopy of the fetal brain with TE = 144 ms (in one case additional TE = 288 ms) was performed in a dynamic mode, and individual spectra of 128 acquisitions were saved. With constructive averaging strategy individual acquisitions were corrected for phase variations and frequency drift before averaging. Constructively averaged spectra were compared to those using conventional averaging to evaluate differences in spectral quality and SNR. RESULTS: The definition of key metabolite peaks was qualitatively improved using constructive averaging, including the doublet structure of lactate in one case. Constructive averaging was associated with SNR increases, ranging from 11% to 40%, and the SNR further improved in one case when outliers from severe motion were rejected before averaging. CONCLUSION: Our results demonstrate the feasibility of using constructive averaging for improving SNR in fetal MRS, which is likely to improve the characterization of fetal brain metabolites.
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Espectroscopia de Ressonância Magnética/métodos , Neuroimagem/métodos , Diagnóstico Pré-Natal/métodos , Estudos de Viabilidade , Feminino , Humanos , GravidezRESUMO
INTRODUCTION: This retrospective study aims to describe systematically the fetal cerebral MR morphology in cases with occipital meningoencephaloceles using standard and advanced fetal MRI techniques. MATERIAL AND METHODS: The 1.5-tesla MR examinations (T1- and T2-weighted imaging, echo planar imaging, EPI, diffusion-weighted imaging, DWI) of 14 fetuses with occipital/parietal meningoencephaloceles were retrospectively analyzed for the classification of anatomic characteristics. A diffusion tensor sequence was performed in 5 cases. RESULTS: In 9/14 cases the occipital lobes were entirely or partially included in the encephalocele sac. Typical features of Chiari III malformation were seen in 6/14 cases. The displaced brain appeared grossly disorganized in 6/14. The brainstem displayed abnormal 'kinking'/rotation (3/14), a z-shape (1/14) and/or a molar tooth-like configuration of the midbrain (3/14). Tractography revealed the presence and position of sensorimotor tracts in 5/5 and the corpus callosum in 3/5. DWI was helpful in the identification of a displaced brain (in 8/9). EPI visualized the anatomy of draining cerebral veins in 7/9 cases. Clinical (9/14) and MRI (7/14) follow-up data are presented. DISCUSSION: Encephaloceles show a wide range of morphological heterogeneity. Fetal MRI serves as an accurate tool in the visualization of brainstem, white matter pathway and cerebral venous involvement and facilitates the detection of specific underlying syndromes such as ciliopathies.
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Cérebro/patologia , Encefalocele/patologia , Doenças Fetais/patologia , Diagnóstico Pré-Natal/métodos , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Gravidez , Estudos RetrospectivosRESUMO
OBJECTIVE: To determine if T1ρ magnetic resonance imaging (T1ρ MRI) could assess early articular cartilage changes in knees of asymptomatic female collegiate athletes. It was hypothesized that impact cohort would demonstrate greater changes than nonimpact cohort. DESIGN: An institutional review board-approved prospective cohort study. Blinded MRI analyses. SETTING: Participants from collegiate athletic program. Imaging at university hospital, February 2008 to July 2009. PARTICIPANTS: Inclusion criteria were female collegiate athletes in athletic season and asymptomatic. Exclusion criteria were previous/current knee injuries/surgeries. Twenty-one female NCAA Division I athletes, 11 impact (basketball players) and 10 nonimpact (swimmers) participants were consented and imaged with 3.0-T MRI (Siemens) and T1ρ sequence (University of Pennsylvania). One patient was removed (injury diagnosis). Final roster was 10 impact and 10 nonimpact participants. No difference in cohort body mass index, height, or weight. MAIN OUTCOME MEASURES: Average T1ρ relaxation times (ART) for patellar and femoral cartilage to analyze defined regions and depth and modified International Cartilage Repair Society classification. RESULTS: Statistical analyses showed that ART of radial zone of central third weight-bearing region of cartilage in basketball players was significantly greater (P = 0.041) than swimmers and ART of the superficial zone in basketball players was significantly less (P = 0.003) than that of swimmers. For both groups, the ART of superficial zones were significantly greater than that of radial zones (P < 0.001). Four impact athletes showed macroscopic changes (none in nonimpact cohort). CONCLUSIONS: T1ρ MRI detected early changes in articular cartilage of asymptomatic collegiate female impact athletes, with significant differences between cohorts in radial zone of central third weight-bearing region and superficial zones ART. Both cohorts showed increased ART in superficial zone. Four impact athletes showed macroscopic changes. CLINICAL RELEVANCE: This study demonstrates a quantitative MRI sequence able to detect signal differences in articular cartilage in asymptomatic athletes.
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Basquetebol , Cartilagem Articular/patologia , Artropatias/diagnóstico , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Natação , Adolescente , Doenças Assintomáticas , Feminino , Humanos , Adulto JovemRESUMO
Since the inception of radiosurgery, the management of brain metastases has become a common problem for neurosurgeons. Although the use of stereotactic radiosurgery and/or whole brain radiation therapy serves to control the majority of disease burden, patients who survive longer than 6-8 months sometimes face the problem of symptomatic radiographically regrowing lesions with few treatment options. Here we investigate the feasibility of use of MRI-guided stereotactic laser induced thermotherapy (LITT) as a novel treatment option for these lesions. Six patients who had previously undergone gamma knife stereotactic radiosurgery for brain metastases were selected. All patients had an initial favorable response to radiosurgery but subsequently developed regrowth of at least one lesion associated with recurrent edema and progressive neurological symptoms requiring ongoing steroids for symptom control. All lesions were evaluated for craniotomy, but were deemed unresectable due to deep location or patient's comorbidities. Stereotactic biopsies were performed prior to the thermotherapy procedure in all cases. LITT was performed using the Visualase system and follow-up MRI imaging was used to determine treatment response. In all six patients biopsy results were negative for tumor and consistent with adverse radiation effects also known as radiation necrosis. Patients tolerated the procedure well and were discharged from the hospital within 48 h of the procedure. In 4/6 cases there was durable improvement of neurological symptoms until death. In all cases steroids were weaned off within 2 months. One patient died from systemic causes related to his cancer a month after the procedure. One patient had regrowth of the lesion 3 months after the procedure and required re-initiation of steroids and standard craniotomy for surgical resection. There were no complications directly related to the thermocoagulation procedure. Stereotactic laser induced thermotherapy is a feasible alternative for the treatment of symptomatic regrowing metastatic lesions after radiosurgery. The procedure carries minimal morbidity and, in this small series, shows some effectiveness in the symptomatic relief of edema and neurological symptoms paralleled by radiographic lesional control. Further studies are necessary to elucidate the safety of this technology.
Assuntos
Neoplasias Encefálicas/terapia , Hipertermia Induzida , Terapia a Laser , Recidiva Local de Neoplasia/terapia , Neoplasias/terapia , Complicações Pós-Operatórias , Radiocirurgia/efeitos adversos , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Neoplasias/mortalidade , Neoplasias/patologia , Prognóstico , Lesões por Radiação/etiologia , Lesões por Radiação/terapia , Taxa de SobrevidaRESUMO
We describe an 11-month-old boy with an unusually large presternal mass present since birth. The large size, fluctuant properties, transillumination, compressibility, and imaging of this lesion were characteristic of a lymphatic malformation. Although four treatments with sclerotherapy markedly reduced its size, it was not until definitive treatment with surgical excision and the final pathology report that we arrived at the ultimate diagnosis of dermoid cyst. Dermoid cysts, although appearing along embryologic lines of closure, are rarely presternal. They are usually small, thick walled, and filled with sebaceous or keratinous fluid, which typically allows for clinical diagnosis, and show characteristic features on magnetic resonance imaging (MRI) and ultrasound. However, this case illustrates that dermoid cysts can appear in somewhat atypical locations, and imaging is not always diagnostic, so dermoid cyst should remain a part of the differential diagnosis for any lesion presenting midsternally, regardless of the size and imaging characteristics.
Assuntos
Cisto Dermoide/diagnóstico , Anormalidades Linfáticas/diagnóstico , Escleroterapia/métodos , Neoplasias Cutâneas/diagnóstico , Biópsia por Agulha , Cisto Dermoide/congênito , Cisto Dermoide/tratamento farmacológico , Diagnóstico Diferencial , Seguimentos , Humanos , Imuno-Histoquímica , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Medição de Risco , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/tratamento farmacológico , Esterno , Parede Torácica/patologia , Resultado do TratamentoRESUMO
In this case report, we present a critical situation during an open calvarial reconstruction involving an 11-month-old infant. The patient experienced accidental extubation, requiring immediate intervention while in the prone position. Approximately two hours post-incision, ventilation became increasingly difficult due to a significant leak detected in the system. On closer inspection, it was observed that both the rubber tourniquet responsible for securing the anesthesia circuit and the tape that held the endotracheal tube in place had become loosened. In response to this emergency, the decision was made to remove the displaced endotracheal tube. We successfully introduced a 1.5 laryngeal mask airway (LMA; Unique™, Teleflex Incorporated, Wayne, PA), which restored ventilation. The patient maintained stable oxygen levels throughout this emergency period, displaying no signs of desaturation. An hour post-intervention, the surgical procedure was completed. The process of removing the LMA was uneventful without any complications. In the setting of emergent airway management, especially for patients in the prone position during surgical procedures, accidental extubation presents a challenge for healthcare providers. This case highlights the importance of prompt decision-making and having alternative airway devices on hand, such as an LMA.
RESUMO
We present a case of a four-year-old male with a history of giant omphalocele who underwent ultrasound-guided Botox injection to bilateral anterior abdominal wall musculature in preparation for definitive repair. Botox administration was successfully combined with preoperative subfascial tissue expanders to achieve definitive midline closure of the anterior abdominal wall defect. Our experience suggests that Botox can be safely used as part of the treatment plan for giant omphalocele repair.