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2.
Artigo em Inglês | MEDLINE | ID: mdl-38485833

RESUMO

Irrespective of whether they are intended for collectors or for the fetish market, dolls are being produced to look more and more realistic with such a degree of life-like detail that they can be mistaken for a real person. This paper reports two cases of misidentification due to this increasing similarity: In the first case, a sex doll was mistaken for a corpse; in the second case, a corpse was mistaken for a doll. While in the latter case, only medical laypersons were at the discovery site, in the first case, an emergency doctor had issued a medical certificate of death for the purported corpse. The medicolegal examiner who was subsequently called to the scene could still rectify the misconception on-site. Mistakes of this nature are likely rare phenomena. It, however, remains to be seen if the increasingly life-like appearance of dolls on the one hand, and the increasingly doll-like appearance of some people, e.g., through cosmetic surgery, will lead to a rise in such cases. To avoid misidentification as in the first reported case, it is essential to prepare medical students well for the task of performing a primary external postmortem examination; it is equally important that fully-trained doctors regularly refresh their expertise in this respect.

3.
Clin Infect Dis ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214897

RESUMO

BACKGROUND: Advancements in access to antiretroviral therapy (ART) and human immunodeficiency virus (HIV) care have led to a decline in acquired immunodeficiency syndrome (AIDS)-related deaths among people with HIV (PWH) in Switzerland. However, data on the ongoing changes in causes of death among PWH over the past 15 years is scarce. METHODS: We investigated all reported deaths in the Swiss HIV Cohort Study between 2005-2022. Causes of death were categorized using the Coding Causes of Death in HIV protocol. The statistical analysis included demographic stratification to identify time trends and logistic regression models to determine associated factors for the underlying cause of death. RESULTS: In total, 1630 deaths were reported, with 23.7% of individuals assigned female at birth. Out of these deaths, 147 (9.0%) were HIV/AIDS-related, 373 (22.9%) due to non-AIDS, non-hepatic (NANH) cancers, 166 (10.2%) liver-related, and 158 (9.7%) cardiovascular-related. The median age at death increased from 45.0 [40.0,53.0] years in 2005-2007 to 61.0 [56.0,69.5] years in 2020-2022. HIV/AIDS and liver-related causes of death decreased, whereas deaths from NANH cancers increased, and cardiovascular-related deaths remained relatively stable. CONCLUSION: The proportionally decreasing HIV/AIDS and liver-related deaths showcase the effectiveness of ART, comprehensive HIV patient care, and interventions targeting hepatitis C virus co-infection. Future research should focus on managing cancer and cardiovascular-related conditions as the new leading causes of death among PWH. Comprehensive healthcare strategies focusing on non-AIDS-related comorbidities, cancer management, and sustaining liver and cardiovascular health are needed to bridge the ongoing health disparities between PWH and the general population.

4.
Eur J Radiol ; 170: 111234, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042021

RESUMO

OBJECTIVE: Pseudolesions of joints are known as focal irregularities of chondral or subchondral bone in typical joint areas and occur frequent but without clinical relevance. This study aims to report the prevalence and describe MRI findings of a previously unreported chondral, mostly posterior located pseudolesion of the distal tibia, and to define criteria to distinguish it from pathologic osteochondral lesions, as well as from another known pseudolesion of this area - the so called "Notch of Harty". MATERIAL AND METHODS: A tri-centric retrospective case-control study included a total of 2,428 patients with ankle MRI examinations performed over a period of 6 years. MRI scans were evaluated by three radiologists in consensus for any cartilage irregularity of the distal tibial articular surface. For this purpose, the tibial articular surface was divided into 9 topographic regions. Proton-density weighted, fat-suppressed sequences in sagittal and coronal acquisition were used to assess the postero-medial articular surface of the tibia. Imaging features such as size and localization of cartilage irregularity and/or a cortical mould as well as presence of associated edema and/or subchondral cysts were reported. Demographic data (sex, age, and weight) was also recorded. Clinical data comprised presence of pain, movement impairment, and concomitant pathologies. RESULTS: A total of 68 patients (34 male, 34 female) with a lesion of the distal tibia were identified that had a new pseudolesion (prevalence of 3%). These lesions occurred most frequently (50 out of 68, 74%) in the postero-medial distal tibia plafond and were more commonly detected in the age group of 9-30 years (47%). In 13 of these 68 cases, the cartilage irregularity was the sole lesion without subchondral abnormalities. By defining these cases as definite pseudolesions, the prevalence was 1% and their age distribution was similar to that of the 55 other lesions with subchondral changes. Here with 11 of the 13 cases the majority (85%) were seen in the posterior part, especially in the postero-medial part (55%) of the distal tibia. The size of the cartilage defect ranged from 1 to 7 mm, and the majority (69%) sized from 2 to 3 mm. In 36 of 68 patients, we have seen subchondral alterations such as edema and/or cysts in addition to cartilage irregularity. 66% (n = 45) of these changes were edema and 37% (n = 25) were cysts. None of these 68 new pseudolesions with or without subchondral changes needed surgical or arthroscopic intervention. In the radiological and orthopaedic reports, clinical symptoms such as pain or instability were never associated with our observed lesions and there was no significant correlation between the presence of motion-related pain and imaging findings of cartilage irregularity, subchondral edema, and subchondral cysts. Thirteen patients had MRI follow-up examinations. Here the lesions did not show any MR morphological changes or clinical deterioration. Besides the new pseudolesion, which occured mainly in the posterior part of the tibia surface, we observed the "Notch of Harty" with a higher prevalence (25%) in our patient cohort. The typical localization was in the antero-medial tibial articular surface, without any edema or cysts. There were no coincidences of patients with both a new pseudolesion and the "Notch of Harty" CONCLUSION: A new pseudolesion is typically seen in the postero-central and postero-medial tibial articular surface with a prevalence of 3% and may be associated with only a small cartilage irregularity. In many cases, however, additional findings such as bone edema and/or an adjacent bone cysts were found, which impairs differentiation of these lesions from pathologic osteochondral lesions. The latter are obviously often associated with a larger cartilage defect and clinical symptoms. Due to the balanced age distribution between those pseudolesions with and without subchondral changes and the lack of clinical symptoms, we conclude that the here reported pseudolesions are not a predilection for a clinically manifest osteochondral lesion (OCL). At the very least, the apparent lack of clinical relevance increases the likelihood that we are dealing with a new true pseudolesion.


Assuntos
Cistos Ósseos , Doenças das Cartilagens , Cartilagem Articular , Cistos , Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Tíbia/patologia , Estudos Retrospectivos , Estudos de Casos e Controles , Doenças das Cartilagens/patologia , Imageamento por Ressonância Magnética/métodos , Cistos Ósseos/patologia , Cistos/patologia , Dor/patologia , Edema/patologia , Cartilagem Articular/patologia
5.
Phys Rev Lett ; 131(12): 120601, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37802949

RESUMO

We use electronic microwave control methods to implement addressed single-qubit gates with high speed and fidelity, for ^{43}Ca^{+} hyperfine "atomic clock" qubits in a cryogenic (100 K) surface trap. For a single qubit, we benchmark an error of 1.5×10^{-6} per Clifford gate (implemented using 600 ns π/2 pulses). For 2 qubits in the same trap zone (ion separation 5 µm), we use a spatial microwave field gradient, combined with an efficient four-pulse scheme, to implement independent addressed gates. Parallel randomized benchmarking on both qubits yields an average error 3.4×10^{-5} per addressed π/2 gate. The scheme scales theoretically to larger numbers of qubits in a single register.

6.
J Fr Ophtalmol ; 2023 Oct 12.
Artigo em Francês | MEDLINE | ID: mdl-37838497

RESUMO

Intravitreal injection (IVI) of a drug allows for immediate intraocular concentrations of active ingredients higher than those obtained by intravenous injection while reducing the risk of systemic side effects. Today, IVI's play a central role in the treatment of many vitreoretinal diseases. With the aging of the population and the advent of vascular endothelial growth factor (VEGF) antagonists, their indications have increased exponentially, creating structural, organizational and economic difficulties. IVI is now one of the most widely performed medical procedures in industrialized countries, and its indications are expected to expand further in the near future with the development of new molecules. Although the overall safety of this practice is proven, an IVI exposes the patient to a 0.05 % risk of endophthalmitis, the consequences of which are often dramatic. This article details the current recommendations, in particular regarding asepsis and antisepsis, and proposes a typical sequence for performing an IVI.

7.
J Nucl Cardiol ; 30(5): 1761-1772, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37592057

RESUMO

BACKGROUND: Although atrial inflammation has been implicated in the pathophysiology of atrial fibrillation (AF), the identification of atrial inflammation remains challenging. We aimed to establish a positron emission tomography/computed tomography (PET/CT) protocol with 18Fluor-labeled fluorodeoxyglucose (18F-FDG) for the detection of atrial hypermetabolism as surrogate for inflammation in AF. METHODS: We included n = 75 AF and n = 75 non-AF patients undergoing three common PET/CT protocols (n = 25 per group) optimized for the detection of (a) inflammation and (b) malignancy in predefined fasting protocols, and (c) cardiac viability allowing for maximized glucose uptake. 18F-FDG-uptake was analyzed in predefined loci. RESULTS: Differences of visual atrial uptake in AF vs non-AF patients were observed in fasting (inflammation [13/25 vs 0/25] and malignancy [10/25 vs 0/25]) protocols while viability protocols showed non-specific uptake in both the groups. In the inflammation protocol, AF patients showed higher uptake in the right atrium [(SUVmax: 2.5 ± .7 vs 2.0 ± .7, P = .01), atrial appendage (SUVmax: 2.4 ± .7 vs 2.0 ± .6, P = .03), and epicardial adipose tissue (SUVmax: 1.4 ± .5 vs 1.1 ± .4, P = .04)]. Malignancy and viability protocols failed to differentiate between AF and non-AF. CONCLUSION: Glucose uptake suppression protocols appear suitable in detecting differential atrial 18F-FDG uptake between AF and non-AF patients. Imaging-based assessment of inflammation might help to stratify AF patients offering individualized therapeutic approaches.


Assuntos
Fibrilação Atrial , Neoplasias , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Fibrilação Atrial/diagnóstico por imagem , Fluordesoxiglucose F18 , Compostos Radiofarmacêuticos , Átrios do Coração/diagnóstico por imagem , Inflamação/diagnóstico por imagem , Glucose , Tomografia por Emissão de Pósitrons
9.
Surg Endosc ; 37(10): 7520-7529, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37418148

RESUMO

BACKGROUND: Delayed bleeding is the most frequent complication after endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR) of large colon polyps. Today, prophylactic clipping with through-the-scope clips (TTSCs) is commonly used to reduce the risk of bleeding. However, the over-the-scope clip (OTSC) system might be superior to TTSCs in achieving hemostasis. This study aims to evaluate the efficacy and safety of prophylactic clipping using the OTSC system after ESD or EMR of large colon polyps. METHODS: This is a retrospective analysis of a prospective collected database from 2009 until 2021 of three endoscopic centers. Patients with large (≥ 20 mm) colon polyps were enrolled. All polyps were removed by either ESD or EMR. After the resection, OTSCs were prophylactically applied on parts of the mucosal defect with a high risk of delayed bleeding or/and perforation. The main outcome measurement was delayed bleeding. RESULTS: A total of 75 patients underwent ESD (67%, 50/75) or EMR (33%, 25/75) in the colorectum. The mean resected specimen diameter was 57 mm ± 24.1 (range 22-98 mm). The mean number of OTSCs placed on the mucosal defect was 2 (range 1-5). None of the mucosal defects were completely closed. Intraprocedural bleeding occurred in 5.3% (ESD 2.0% vs. EMR 12.0%; P = 0.105), and intraprocedural perforation occurred in 6.7% (ESD 8% vs. EMR 4%; P = 0.659) of the patients. Hemostasis was achieved in 100% of cases of intraprocedural bleeding, whereas two patients required surgical conversion due to intraprocedural perforation. Among the remaining 73 patients who received prosphylactic clipping, delayed bleeding occurred in 1.4% (ESD 0% vs. EMR 4.2%; P = 0.329), and delayed perforation occurred in 0%. CONCLUSIONS: The prophylactic partial closure of large post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation. The prophylactic partial closure of large complex post-ESD/EMR mucosal defects using OTSCs could serve as an effective strategy to reduce the risk of delayed bleeding and perforation.


Assuntos
Pólipos do Colo , Ressecção Endoscópica de Mucosa , Humanos , Ressecção Endoscópica de Mucosa/efeitos adversos , Estudos Retrospectivos , Estudos Prospectivos , Resultado do Tratamento , Pólipos do Colo/cirurgia , Colo
10.
Rev Med Interne ; 44(5): 227-252, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37147233

RESUMO

This French National Diagnostic and Care Protocol (NDPC) includes both pediatric and adult patients with non-infectious chronic uveitis (NICU) or non-infectious recurrent uveitis (NIRU). NICU is defined as uveitis that persists for at least 3 months or with frequent relapses occurring less than 3 months after cessation of treatment. NIRU is repeated episodes of uveitis separated by periods of inactivity of at least 3 months in the absence of treatment. Some of these NICU and NIRU are isolated. Others are associated with diseases that may affect various organs, such as uveitis associated with certain types of juvenile idiopathic arthritis, adult spondyloarthropathies or systemic diseases in children and adults such as Behçet's disease, granulomatoses or multiple sclerosis. The differential diagnoses of pseudo-uveitis, sometimes related to neoplasia, and uveitis of infectious origin are discussed, as well as the different forms of uveitis according to their main anatomical location (anterior, intermediate, posterior or panuveitis). We also describe the symptoms, known physiopathological mechanisms, useful complementary ophthalmological and extra-ophthalmological examinations, therapeutic management, monitoring and useful information on the risks associated with the disease or treatment. Finally, this protocol presents more general information on the care pathway, the professionals involved, patient associations, adaptations in the school or professional environment and other measures that may be implemented to manage the repercussions of these chronic diseases. Because local or systemic corticosteroids are usually necessary, these treatments and the risks associated with their prolonged use are the subject of particular attention and specific recommendations. The same information is provided for systemic immunomodulatory treatments, immunosuppressive drugs, sometimes including anti-TNFα antibodies or other biotherapies. Certain particularly important recommendations for patient management are highlighted in summary tables.


Assuntos
Síndrome de Behçet , Esclerose Múltipla , Uveíte , Adulto , Humanos , Criança , Uveíte/diagnóstico , Uveíte/epidemiologia , Uveíte/etiologia , Síndrome de Behçet/complicações , Corticosteroides/uso terapêutico , Imunossupressores/uso terapêutico , Esclerose Múltipla/complicações
11.
J Maxillofac Oral Surg ; 22(Suppl 1): 98-104, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37041957

RESUMO

Introduction: Up to the second half of the twentieth century, pedicled flaps marked the gold standard in reconstructive surgery. Followed by the introduction of microsurgical techniques, these flaps were increasingly abandoned. We conducted a retrospective study to determine the value of two-stage pedicle flaps in modern maxillofacial reconstruction. Material & Methods: A chart review from October 2017 to November 2020 was performed to identify patients who were treated by a two-stage pedicle flap in our Department of Oral and Maxillofacial Surgery. Results: A total of 31 patients, 17 female and 14 males received 36 two-stage pedicle flaps. All patients were in noticeably impaired health condition with a majority of ASA-score 3. The defect location mainly contained extraoral resections (58.3%). A variety of flaps were harvested consisting of buccal flaps, Abbe flaps, forehead flaps, deltopectoral flaps, nasolabial flaps, and a tubed flap. Discussion: The study outlines two indications for the use of two-stage pedicle flaps. Firstly, as a back-up strategy in heavily pre-treated wound beds and secondly in an almost contrarily indication as a first-choice reconstructive option of the facial skin in esthetic demanding cases. Conclusion: The timesaving and straight forward surgical approach as well as their low postsurgical complications and strong long-time success rates secure the two-stage pedicle flap a justified niche role in times of microsurgical maxillofacial reconstruction. Supplementary Information: The online version contains supplementary material available at 10.1007/s12663-021-01635-9.

12.
Phys Rev Lett ; 130(9): 090803, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930909

RESUMO

We integrate a long-lived memory qubit into a mixed-species trapped-ion quantum network node. Ion-photon entanglement first generated with a network qubit in ^{88}Sr^{+} is transferred to ^{43}Ca^{+} with 0.977(7) fidelity, and mapped to a robust memory qubit. We then entangle the network qubit with a second photon, without affecting the memory qubit. We perform quantum state tomography to show that the fidelity of ion-photon entanglement decays ∼70 times slower on the memory qubit. Dynamical decoupling further extends the storage duration; we measure an ion-photon entanglement fidelity of 0.81(4) after 10 s.

13.
Phys Rev Lett ; 130(8): 086704, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36898116

RESUMO

We report the manifestation of field-induced Berezinskii-Kosterlitz-Thouless (BKT) correlations in the weakly coupled spin-1/2 Heisenberg layers of the molecular-based bulk material [Cu(pz)_{2}(2-HOpy)_{2}](PF_{6})_{2}. At zero field, a transition to long-range order occurs at 1.38 K, caused by a weak intrinsic easy-plane anisotropy and an interlayer exchange of J^{'}/k_{B}≈1 mK. Because of the moderate intralayer exchange coupling of J/k_{B}=6.8 K, the application of laboratory magnetic fields induces a substantial XY anisotropy of the spin correlations. Crucially, this provides a significant BKT regime, as the tiny interlayer exchange J^{'} only induces 3D correlations upon close approach to the BKT transition with its exponential growth in the spin-correlation length. We employ nuclear magnetic resonance measurements to probe the spin correlations that determine the critical temperatures of the BKT transition as well as that of the onset of long-range order. Further, we perform stochastic series expansion quantum Monte Carlo simulations based on the experimentally determined model parameters. Finite-size scaling of the in-plane spin stiffness yields excellent agreement of critical temperatures between theory and experiment, providing clear evidence that the nonmonotonic magnetic phase diagram of [Cu(pz)_{2}(2-HOpy)_{2}](PF_{6})_{2} is determined by the field-tuned XY anisotropy and the concomitant BKT physics.

14.
J Fr Ophtalmol ; 46(4): 311-321, 2023 Apr.
Artigo em Francês | MEDLINE | ID: mdl-36804114

RESUMO

INTRODUCTION: The main risk factors for graft failure in penetrating keratoplasty are well known. However, few studies have examined donor characteristics or more precise data on endothelial keratoplasty. MATERIALS AND METHODS: This was a retrospective, single-center study at the Nantes University Hospital, aiming to identify factors predictive of one-year success or failure of eye bank UT-DSAEK endothelial keratoplasty grafts prepared between May 2016 and October 2018. The outcome measure was success or failure at 12months post keratoplasty. RESULTS: One hundred and five grafts were included: 93 successes and 12 failures at 12months. The failure rate was higher in 2016 compared to 2017 and 2018. The characteristics associated with higher failure rate were elderly donor, shorter time between harvesting and grafting, lower endothelial cell density, significant pre-graft endothelial cell loss, re-graft for Fuchs dystrophy, history of corneal transplant. DISCUSSION: Our results are consistent with those in the literature. However, some factors, such as the type of corneal harvesting or pre-graft endothelial cell loss, were not found. UT-DSAEK has demonstrated better results than DSAEK, but still appears to be somewhat inferior to DMEK. CONCLUSION: The main factor for graft failure in our study was an early re-graft within 12months. However, the low incidence of graft failure limits interpretation of these results.


Assuntos
Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior , Distrofia Endotelial de Fuchs , Humanos , Idoso , Estudos Retrospectivos , Bancos de Olhos , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/efeitos adversos , Ceratoplastia Endotelial com Remoção da Lâmina Limitante Posterior/métodos , Distrofia Endotelial de Fuchs/cirurgia , Fatores de Risco , Endotélio Corneano/transplante , Sobrevivência de Enxerto
16.
J Cancer Res Clin Oncol ; 149(7): 2929-2936, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35831764

RESUMO

PURPOSE: The effect of the duration of an educational rotation presented at a palliative care unit on the palliative care knowledge gain and the increase of palliative care self-efficacy expectations are unclear. METHODS: This national prospective multicenter pre-post survey conducted at twelve German University Comprehensive Cancer Centers prospectively enrolled physicians who were assigned to training rotations in specialized palliative care units for three, six, or twelve months. Palliative care knowledge [in %] and palliative care self-efficacy expectations [max. 57 points] were evaluated before and after the rotation with a validated questionnaire. RESULTS: From March 2018 to October 2020, questionnaires of 43 physicians were analyzed. Physicians participated in a 3- (n = 3), 6- (n = 21), or 12-month (n = 19) palliative care rotation after a median of 8 (0-19) professional years. The training background of rotating physicians covered a diverse spectrum of specialties; most frequently represented were medical oncology (n = 15), and anesthesiology (n = 11). After the rotation, median palliative care knowledge increased from 81.1% to 86.5% (p < .001), and median palliative care self-efficacy expectations scores increased from 38 to 50 points (p < .001). The effect of the 12-month rotation was not significantly greater than that of the 6-month rotation. CONCLUSION: An educational rotation presented in a specialized palliative care unit for at least six months significantly improves palliative care knowledge and palliative care self-efficacy expectations of physicians from various medical backgrounds.


Assuntos
Hospitais para Doentes Terminais , Oncologistas , Humanos , Cuidados Paliativos , Hospitais Universitários , Estudos Prospectivos , Atitude do Pessoal de Saúde , Inquéritos e Questionários
17.
Ultrasound Obstet Gynecol ; 61(5): 601-609, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36445348

RESUMO

OBJECTIVE: To investigate human femur development in fetal growth restriction (FGR) by analyzing femur morphometrics and distal epimetaphyseal features on prenatal magnetic resonance imaging (MRI). METHODS: This was a retrospective study of 111 fetuses (mean gestational age (GA), 27 + 2 weeks (range, 19-35 weeks)) with FGR associated with placental insufficiency without other major abnormalities and 111 GA-matched normal controls. On 1.5-Tesla echoplanar MRI, femur morphometrics, including diaphyseal length, epiphyseal length and epiphyseal width, were assessed. Using a previously reported grading system, epimetaphyseal features, including cartilaginous epiphyseal shape, metaphyseal shape and epiphyseal ossification, were analyzed qualitatively. To compare FGR cases and controls, the paired t-test was used to assess morphometrics, generalized estimating equations were used for epimetaphyseal features and time-to-event analysis was used to assess the visibility of epiphyseal ossification. RESULTS: There were significant differences in femur morphometrics between FGR cases and controls (all parameters, P < 0.001), with bone shortening observed in FGR. No significant differences were found in the distribution of epimetaphyseal features between FGR cases and controls (epiphyseal shape, P = 0.341; metaphyseal shape, P = 0.782; epiphyseal ossification, P = 0.85). Epiphyseal ossification was visible at a median of 33.6 weeks in FGR cases and at 32.1 weeks in controls (P = 0.008). CONCLUSIONS: On prenatal MRI, cases with FGR associated with placental insufficiency exhibit diaphyseal and epiphyseal shortening of the femur. However, FGR cases and normal controls share similarly graded distal epimetaphyseal features. Consequently, these features may not be appropriate MRI characteristics for the identification of FGR. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Retardo do Crescimento Fetal , Insuficiência Placentária , Gravidez , Feminino , Humanos , Retardo do Crescimento Fetal/diagnóstico por imagem , Retardo do Crescimento Fetal/patologia , Insuficiência Placentária/diagnóstico por imagem , Placenta/diagnóstico por imagem , Estudos Retrospectivos , Fêmur/diagnóstico por imagem , Idade Gestacional , Imageamento por Ressonância Magnética/métodos , Ultrassonografia Pré-Natal
19.
AJNR Am J Neuroradiol ; 43(12): 1817-1823, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36396336

RESUMO

BACKGROUND AND PURPOSE: Multidynamic multiecho sequence-based imaging enables investigators to reconstruct multiple MR imaging contrasts on the basis of a single scan. This study investigated the feasibility of synthetic MRI-based WM signal suppression (syWMSS), a synthetic inversion recovery approach in which a short TI suppresses myelin-related signals, for the identification of early myelinating brainstem pathways. MATERIALS AND METHODS: Thirty-one cases of neonatal MR imaging, which included multidynamic multiecho data and conventionally acquired T1- and T2-weighted sequences, were analyzed. The multidynamic multiecho postprocessing software SyMRI was used to generate syWMSS data (TR/TE/TI = 3000/5/410 ms). Two raters discriminated early myelinating brainstem pathways (decussation of the superior cerebellar peduncle, medial lemniscus, central tegmental tract, and medial longitudinal fascicle [the latter 3 assessed at the level of the pons]) on syWMSS data and reference standard contrasts. RESULTS: On the basis of syWMSS data, the decussation of the superior cerebellar peduncle (31/31); left/right medial lemniscus (31/31; 30/31); left/right central tegmental tract (19/31; 20/31); and left/right medial longitudinal fascicle (30/31) were reliably identified by both raters. On the basis of T1-weighted contrasts, the decussation of the superior cerebellar peduncle (14/31); left/right medial lemniscus (22/31; 16/31); left/right central tegmental tract (1/31); and left/right medial longitudinal fascicle (9/31; 8/31) were reliably identified by both raters. On the basis of T2-weighted contrasts, the decussation of the superior cerebellar peduncle (28/31); left/right medial lemniscus (16/31; 12/31); left/right central tegmental tract (23/31; 18/31); and left/right medial longitudinal fascicle (15/31; 14/31) were reliably identified by both raters. CONCLUSIONS: syWMSS data provide a feasible imaging technique with which to study early myelinating brainstem pathways. MR imaging approaches that use myelin signal suppression contribute to a more sensitive assessment of myelination patterns at early stages of cerebral development.


Assuntos
Imageamento por Ressonância Magnética , Substância Branca , Recém-Nascido , Humanos , Imageamento por Ressonância Magnética/métodos , Tronco Encefálico/diagnóstico por imagem , Ponte , Bainha de Mielina
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