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1.
Actas Dermosifiliogr ; 2024 Jul 02.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38964604

RESUMEN

BACKGROUND: Acute radiation dermatitis (ARD) is the most widely reported radiotherapy-induced adverse event. Currently, there is no objective or reliable method to measure ARD. OBJECTIVE: Our main objective was to identify and quantify the effects of radiotherapy with a computational model using optical coherence tomography (OCT) skin scanning. Secondary objectives included determining the ARD impact of different radiotherapeutic schemes and adjuvant topical therapies. METHODS: We conducted a prospective, single-center case series study in a tertiary referral center of patients with breast cancer who were eligible for whole breast radiotherapy (WBRT). RESULTS: A total of 39 women were included and distributed according to the radiotherapeutic schemes (15, 20, and 25 fractions). A computational model was designed to quantitatively analyze OCT findings. After radiotherapy, OCT scanning was more sensitive revealing vascularization changes in 84.6% of the patients (vs 69.2% of the patients with ARD by clinical examination). OCT quantified an increased vascularization at the end of WBRT (P<.05) and a decrease after 3 months (P=.032). Erythematous skin changes by OCT were more pronounced in the 25-fraction regime. CONCLUSION: An OCT computational model allowed for the identification and quantification of vascularization changes on irradiated skin, even in the absence of clinical ARD. This may allow the design of standardized protocols for ARD beyond the skin color of the patients involved.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38924150

RESUMEN

BACKGROUND: Facial (FP) and genital psoriasis (GP) significantly affect patients' quality of life. Despite the advances in treatments, limited data on efficacy and safety are available on these difficult-to-treat areas. Guselkumab is an interleukin (IL)-23 inhibitor which has been proven effective in treating patients with moderate-to-severe plaque psoriasis. OBJECTIVES: The aim of this interim analysis was to report the efficacy and safety of guselkumab in the treatment of patients with FP and/or GP. MATERIALS AND METHODS: GULLIVER is a 52-week Italian observational study to evaluate the effectiveness and safety of guselkumab in a real-life setting in patients with FP and/or GP. Adult patients with facial and/or genital moderate-to-severe psoriasis (sPGA score ≥ 3) were included. The primary endpoint of this analysis was the percentage of patients achieving a facial or genital sPGA score of 0 (clear) or 1 (almost clear), at Week 12. The change in the score of the facial or genital sPGA components in patients with a score ≥3 for each sPGA component was assessed. PASI score in patients with a baseline PASI above or below 10 was evaluated. RESULTS: Overall, 351 patients were included in the study; 83.3% of FP and 76.5% of GP patients achieved the primary endpoint. Similar response rates were observed for the facial or genital sPGA components in patients with a baseline facial or genital sPGA score ≥3 in each component. Among patients with a baseline PASI score >10, mean PASI score improved from 19.0 (SD 8.3) to 2.2 (SD 4.8). Forty-four AEs were observed in 32 patients; two mild and transient AEs (fatigue and nausea) were considered treatment related. No SAEs were observed. CONCLUSIONS: Guselkumab, showing to be effective and safe in treating FP and GP, may be a valid therapeutic option for patients with psoriasis localized in these difficult-to-treat areas.

3.
Actas Dermosifiliogr ; 2024 Mar 28.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38554749

RESUMEN

BACKGROUND: Acute radiation dermatitis (ARD) is the most widely reported radiotherapy-induced adverse event. Currently, there is no objective or reliable method to measure ARD. OBJECTIVE: Our main objective was to identify and quantify the effects of radiotherapy with a computational model using optical coherence tomography (OCT) skin scanning. Secondary objectives included determining the ARD impact of different radiotherapeutic schemes and adjuvant topical therapies. METHODS: We conducted a prospective, single-center case series study in a tertiary referral center of patients with breast cancer who were eligible for whole breast radiotherapy (WBRT). RESULTS: A total of 39 women were included and distributed according to the radiotherapeutic schemes (15, 20, and 25 fractions). A computational model was designed to quantitatively analyze OCT findings. After radiotherapy, OCT scanning was more sensitive revealing vascularization changes in 84.6% of the patients (vs 69.2% of the patients with ARD by clinical examination). OCT quantified an increased vascularization at the end of WBRT (P<.05) and a decrease after 3 months (P=.032). Erythematous skin changes by OCT were more pronounced in the 25-fraction regime. CONCLUSION: An OCT computational model allowed for the identification and quantification of vascularization changes on irradiated skin, even in the absence of clinical ARD. This may allow the design of standardized protocols for ARD beyond the skin color of the patients involved.

4.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): 258-264, Mar. 2024. ilus, tab
Artículo en Español | IBECS | ID: ibc-231399

RESUMEN

La terminología usada para describir los diferentes hallazgos en la microscopía confocal de reflectancia (MCR), tanto en lesiones melanocíticas, como en no melanocíticas se ha consensuado en inglés. En el presente trabajo, se proponen los términos en español que mejor interpretan estos conceptos ya descritos para la MCR, mediante el consenso de expertos de distintas nacionalidades de habla hispana y utilizando el método DELPHI para el acuerdo final. Se obtuvieron 52 términos en total, de los cuales 28 fueron para lesiones melanocíticas y 24 para lesiones no melanocíticas. El uso de la nomenclatura propuesta permitirá una homogeneización y mejor entendimiento de las estructuras; una descripción más estandarizada en los registros clínicos y una mejor interpretación de estos informes por otros dermatólogos.(AU)


The terminology used to describe reflectance confocal microscopy (RCM) findings in both melanocytic and nonmelanocytic lesions has been standardized in English. We convened a panel of Spanish-speaking RCM experts and used the Delphi method to seek consensus on which Spanish terms best describe RCM findings in this setting. The experts agreed on 52 terms: 28 for melanocytic lesions and 24 for nonmelanocytic lesions. The resulting terminology will facilitate homogenization, leading to a better understanding of structures, more standardized descriptions in clinical registries, and easier interpretation of clinical reports exchanged between dermatologists.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Terminología como Asunto , Microscopía Confocal , Hallazgos Morfológicos y Microscópicos , Carcinoma Basocelular/diagnóstico por imagen , Melanoma/microbiología , Traducción
5.
Actas dermo-sifiliogr. (Ed. impr.) ; 115(3): T258-T264, Mar. 2024. ilus, tab
Artículo en Inglés | IBECS | ID: ibc-231400

RESUMEN

La terminología usada para describir los diferentes hallazgos en la microscopía confocal de reflectancia (MCR), tanto en lesiones melanocíticas, como en no melanocíticas se ha consensuado en inglés. En el presente trabajo, se proponen los términos en español que mejor interpretan estos conceptos ya descritos para la MCR, mediante el consenso de expertos de distintas nacionalidades de habla hispana y utilizando el método DELPHI para el acuerdo final. Se obtuvieron 52 términos en total, de los cuales 28 fueron para lesiones melanocíticas y 24 para lesiones no melanocíticas. El uso de la nomenclatura propuesta permitirá una homogeneización y mejor entendimiento de las estructuras; una descripción más estandarizada en los registros clínicos y una mejor interpretación de estos informes por otros dermatólogos.(AU)


The terminology used to describe reflectance confocal microscopy (RCM) findings in both melanocytic and nonmelanocytic lesions has been standardized in English. We convened a panel of Spanish-speaking RCM experts and used the Delphi method to seek consensus on which Spanish terms best describe RCM findings in this setting. The experts agreed on 52 terms: 28 for melanocytic lesions and 24 for nonmelanocytic lesions. The resulting terminology will facilitate homogenization, leading to a better understanding of structures, more standardized descriptions in clinical registries, and easier interpretation of clinical reports exchanged between dermatologists.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Terminología como Asunto , Microscopía Confocal , Hallazgos Morfológicos y Microscópicos , Carcinoma Basocelular/diagnóstico por imagen , Melanoma/microbiología , Traducción
7.
J Eur Acad Dermatol Venereol ; 38(1): 124-135, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37669864

RESUMEN

BACKGROUND: In vivo reflectance confocal microscopy (RCM) enables the study of architectural and cytological aspects in horizontal sections, which closely correlate with histologic features. However, traditional histopathological vertical sections cannot totally reproduce the image of the in vivo RCM horizontal section. OBJECTIVE: To evaluate the concordance between in vivo RCM and histopathologic transverse sections for melanocytic lesions, basal cell carcinoma and seborrheic keratoses. METHODS: Prospectively collected benign melanocytic and non-melanocytic tumours diagnosed by dermoscopy were evaluated for common RCM features and compared to histopathology in horizontal sections with haematoxylin and eosin staining. RESULTS: A total of 44 skin tumours including 19 melanocytic lesions (nine compound, five junctional and five intradermal nevi), 12 basal cell carcinomas and 13 seborrheic keratoses were collected in the Department of Dermatology of Hospital Clinic of Barcelona. The RCM features that had statistically significant agreement with the histopathological horizontal sections were the preserved and visible honeycomb pattern, well defined DEJ, small bright particles, dermal nests, tumour islands and dark silhouettes, clefting, collagen bundles, thickened collagen bundles and cytologic atypia. CONCLUSIONS: Histopathology evaluation of horizontal sections of skin tumours can be correlated with main RCM findings. The results of this study have improved the understanding and interpretation of RCM features in relation to skin tumours, thus reinforcing the utility of RCM as a diagnostic tool.


Asunto(s)
Carcinoma Basocelular , Queratosis Seborreica , Melanoma , Nevo Pigmentado , Neoplasias Cutáneas , Humanos , Melanoma/patología , Queratosis Seborreica/diagnóstico por imagen , Nevo Pigmentado/patología , Dermoscopía/métodos , Microscopía Confocal/métodos , Neoplasias Cutáneas/patología , Carcinoma Basocelular/diagnóstico por imagen , Colágeno
8.
Actas Dermosifiliogr ; 115(3): 258-264, 2024 Mar.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37890615

RESUMEN

The terminology used to describe reflectance confocal microscopy (RCM) findings in both melanocytic and nonmelanocytic lesions has been standardized in English. We convened a panel of Spanish-speaking RCM experts and used the Delphi method to seek consensus on which Spanish terms best describe RCM findings in this setting. The experts agreed on 52 terms: 28 for melanocytic lesions and 24 for nonmelanocytic lesions. The resulting terminology will facilitate homogenization, leading to a better understanding of structures, more standardized descriptions in clinical registries, and easier interpretation of clinical reports exchanged between dermatologists.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/patología , Melanoma/diagnóstico por imagen , Melanoma/patología , Técnica Delphi , Microscopía Confocal/métodos , Consenso , Dermoscopía/métodos
11.
J Eur Acad Dermatol Venereol ; 37(12): 2498-2508, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37611275

RESUMEN

BACKGROUND: Most of large epidemiological studies on melanoma susceptibility have been conducted on fair skinned individuals (US, Australia and Northern Europe), while Southern European populations, characterized by high UV exposure and dark-skinned individuals, are underrepresented. OBJECTIVES: We report a comprehensive pooled analysis of established high- and intermediate-penetrance genetic variants and clinical characteristics of Mediterranean melanoma families from the MelaNostrum Consortium. METHODS: Pooled epidemiological, clinical and genetic (CDKN2A, CDK4, ACD, BAP1, POT1, TERT, and TERF2IP and MC1R genes) retrospective data of melanoma families, collected within the MelaNostrum Consortium in Greece, Italy and Spain, were analysed. Univariate methods and multivariate logistic regression models were used to evaluate the association of variants with characteristics of families and of affected and unaffected family members. Subgroup analysis was performed for each country. RESULTS: We included 839 families (1365 affected members and 2123 unaffected individuals). Pathogenic/likely pathogenic CDKN2A variants were identified in 13.8% of families. The strongest predictors of melanoma were ≥2 multiple primary melanoma cases (OR 8.1; 95% CI 3.3-19.7), >3 affected members (OR 2.6; 95% CI 1.3-5.2) and occurrence of pancreatic cancer (OR 4.8; 95% CI 2.4-9.4) in the family (AUC 0.76, 95% CI 0.71-0.82). We observed low frequency variants in POT1 (3.8%), TERF2IP (2.5%), ACD (0.8%) and BAP1 (0.3%). MC1R common variants (≥2 variants and ≥2 RHC variants) were associated with melanoma risk (OR 1.4; 95% CI 1.0-2.0 and OR 4.3; 95% CI 1.2-14.6, respectively). CONCLUSIONS: Variants in known high-penetrance genes explain nearly 20% of melanoma familial aggregation in Mediterranean areas. CDKN2A melanoma predictors were identified with potential clinical relevance for cancer risk assessment.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/genética , Estudios Retrospectivos , Mutación , Predisposición Genética a la Enfermedad , Melanoma/epidemiología , Melanoma/genética , Melanoma/patología , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Mutación de Línea Germinal , Receptor de Melanocortina Tipo 1/genética
12.
J Endocrinol Invest ; 46(4): 805-814, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36323983

RESUMEN

PURPOSE: To compare the intraoperative and surgical outcomes of normotensive pheochromocytomas and sympathetic paragangliomas (PPGLs), hypertensive PPGLs and non-PPGL adrenal lesions. METHODS: This a retrospective multicenter cohort study of patients with PPGLs from 18 tertiary hospitals. A control group of histologically confirmed adrenocortical adenomas (non-PPGL group) was selected to compare intraoperative and surgical outcomes with of the normotensive PPGLs. RESULTS: Two hundred and ninety-six surgeries performed in 289 patients with PPGLs were included. Before surgery, 209 patients were classified as hypertensive PPGLs (70.6%) and 87 as normotensive PPGLs. A higher proportion of normotensive PPGLs than hypertensive PPGLs did not receive alpha presurgical blockade (P = 0.009). When we only considered those patients who received presurgical alpha blockers (200 hypertensive PPGLs and 76 normotensive PPGLs), hypertensive PPGLs had a threefold higher risk of intraoperative hypertensive crisis (OR 3.0 [95% 1.3-7.0]) and of hypotensive episodes (OR 2.9 [95% CI 1.2-6.7]) than normotensive PPGLs. When we compared normotensive PPGLs (n = 76) and non-PPGLs (n = 58), normotensive PPGLs had a fivefold higher risk of intraoperative complications (OR 5.3 [95% CI 1.9-14.9]) and a six times higher risk of postoperative complications (OR 6.1 [95% CI 1.7-21.6]) than non-PPGLs. CONCLUSION: Although the risk of intraoperative hypertensive and hypotensive episodes in normotensive PPGLs is significantly lower than in hypertensive PPGLs, normotensive PPGLs have a greater risk of intraoperative and postoperative complications than non-PPGL adrenal lesions. Therefore, it is recommended to follow the standard of care for presurgical and anesthetic management of PPGLs also in normotensive PPGLs.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Hipertensión , Paraganglioma , Feocromocitoma , Humanos , Feocromocitoma/cirugía , Feocromocitoma/patología , Estudios de Cohortes , Paraganglioma/cirugía , Paraganglioma/patología , Hipertensión/epidemiología , Neoplasias de las Glándulas Suprarrenales/cirugía , Neoplasias de las Glándulas Suprarrenales/patología , Resultado del Tratamiento
13.
J Eur Acad Dermatol Venereol ; 36(12): 2364-2372, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35882522

RESUMEN

BACKGROUND: Around 0.5% of cutaneous melanoma (CM) patients will present with synchronous melanomas when first seen. Moreover, 26-40% of patients with multiple primary melanomas present with synchronous lesions. OBJECTIVES: To assess the prevalence, clinical and histopathological characteristics, germline mutations and outcome in patients with synchronous melanoma. METHODS: Clinical and histopathological data from 4703 melanoma patients were included. Clinical, histological and genetic mutational status information was analysed. Kaplan-Meier curves were used to investigate survival outcomes. RESULTS: A total of 144 patients (3.06%) presented simultaneously with two or more primary melanomas. During follow-up, 25.7% of patients with synchronous melanoma developed a new primary melanoma compared to 8.6% of patients diagnosed with single melanoma (P < 0.001). Germinal CDKN2A mutations were identified in 10.7% of patients with synchronous melanomas and genetic variants in MC1R in 72%. No significant differences in all survival outcomes between patients with synchronous melanomas and single melanomas were found. CONCLUSION: Synchronous melanomas are more frequent than previously reported and are more frequent in older patients compared to single melanomas. Moreover, these patients have a higher risk of developing a new primary melanoma during follow-up and have higher rates of germline susceptibility variants. Nevertheless, these findings were not associated with worse outcomes.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Anciano , Melanoma/patología , Neoplasias Cutáneas/patología , Mutación de Línea Germinal , Antecedentes Genéticos , Melanoma Cutáneo Maligno
16.
Br J Dermatol ; 185(4): 756-763, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33453061

RESUMEN

BACKGROUND: Some studies have suggested a relationship between type 2 diabetes mellitus (T2DM) and increased incidence of melanoma. Efforts are under way to identify preventable and treatable factors associated with greater melanoma aggressiveness, but no studies to date have examined the relationship between T2DM and the aggressiveness of cutaneous melanoma at diagnosis. OBJECTIVES: To explore potential associations between T2DM, glycaemic control and metformin treatment and the aggressiveness of cutaneous melanoma. METHODS: We conducted a cross-sectional multicentric study in 443 patients diagnosed with cutaneous melanoma. At diagnosis, all patients completed a standardized protocol, and a fasting blood sample was extracted to analyse their glucose levels, glycated haemoglobin concentration and markers of systemic inflammation. Melanoma characteristics and aggressiveness factors [Breslow thickness, ulceration, tumour mitotic rate (TMR), sentinel lymph node (SLN) involvement and tumour stage] were also recorded. RESULTS: The mean (SD) age of the patients was 55·98 (15·3) years and 50·6% were male. The median Breslow thickness was 0·85 mm. In total, 48 (10·8%) patients were diagnosed with T2DM and this finding was associated with a Breslow thickness > 2 mm [odds ratio (OR) 2·6, 95% confidence interval (CI) 1·4-4·9; P = 0·004)] and > 4 mm (OR 3·6, 95% CI 1·7-7·9; P = 0·001), TMR > 5 per mm2 (OR 4·5, 95% CI 1·4-13·7; P = 0·009), SLN involvement (OR 2·3, 95% CI 1-5·7; P = 0·038) and tumour stages III-IV (vs. I-II) (OR 3·4, 95% CI 1·6-7·4; P = 0·002), after adjusting for age, sex, obesity, alcohol intake and smoking habits. No significant associations emerged between glycated haemoglobin levels, metformin treatment and melanoma aggressiveness. CONCLUSIONS: T2DM, rather than glycaemic control and metformin treatment, is associated with increased cutaneous melanoma aggressiveness at diagnosis.


Asunto(s)
Diabetes Mellitus Tipo 2 , Melanoma , Ganglio Linfático Centinela , Neoplasias Cutáneas , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Humanos , Masculino , Melanoma/epidemiología , Persona de Mediana Edad
17.
J Eur Acad Dermatol Venereol ; 35(3): 650-657, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32743829

RESUMEN

BACKGROUND: The anatomical location of atypical melanocytic skin lesion (aMSL) was never combined into an algorithm for discriminating early melanomas (EM) from atypical nevi (AN). AIMS: To investigate the impact of body location on the intuitive diagnosis performed in teledermoscopy by dermatologists of different skill levels. A further aim was to evaluate how the integration of the body location could improve an algorithm-aided diagnosis. METHODS: We retrospectively collected 980 standardized dermoscopic images of aMSL cases (663 AN, 317 EM): data on the anatomical location were collected according to 15 body sites classified into 4 macro-areas of chronically/frequently/seldom/rarely exposure. Through a teledermatology web platform, 111 variously skilled dermoscopists performed either the intuitive diagnosis and 3 algorithm-assisted diagnostic tests (i.e. iDScore, 7-point checklist, ABCD rule) on each case, for a total of 3330 examinations. RESULTS: In the rarely photoexposed area (side, bottom, abdomen), AN were the most tricky (i.e. highest quote of false positives), due to a frequent recognition of dermoscopic features usually considered as suggestive for melanoma in these lesions; the EM at these sites received the highest quote of false negatives, being generally interpreted as 'featureless' according to these traditional parameters, that were more frequently displayed on the chronically photoexposed area. In rarely and seldom photoexposed area, intuitive diagnosis fails to achieve adequate accuracy for all aMSLs, as the ABCD rule and the 7-point checklist; by applying the iDScore algorithm the diagnostic performance was increased by 15% in young and 17% in experts. CONCLUSIONS: The body location of an aMSL can affect the quality of intuitive dermoscopic diagnosis, especially in sun-protected areas. Accuracy can be improved by using the iDScore algorithm that assigns a different partial score of each body site.


Asunto(s)
Melanoma , Nevo , Neoplasias Cutáneas , Dermoscopía , Diagnóstico Diferencial , Humanos , Melanoma/diagnóstico por imagen , Nevo/diagnóstico , Estudios Retrospectivos , Neoplasias Cutáneas/diagnóstico por imagen , Luz Solar
19.
J Eur Acad Dermatol Venereol ; 35(2): 403-410, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32455486

RESUMEN

BACKGROUND: MC1R polymorphisms interact with CDKN2A mutations modulating melanoma risk and contribute to a less suspicious clinical and dermoscopic appearance of melanomas. Different strategies, including dermoscopic comparative approach and digital monitoring, are used for the melanoma diagnosis in this context. OBJECTIVE: To analyse the diagnostic accuracy of the morphologic approach and comparative approach in dermoscopy, and to detect melanoma in familial melanoma (FamMM) patients according to different genetic backgrounds. METHODS: Two independent readers evaluated 415 lesions belonging to 25 FamMM: 26 melanomas (62% in situ, 36% early invasive) and 389 naevi, blinded for dermoscopic and histopathologic diagnosis, following two different steps. First step-Randomized: all lesions were randomly located in one single folder. Second step-Comparative approach: the lesions were clustered by patient. Sensitivity, specificity and number needed to excise (NNE) for melanoma diagnosis were calculated for both diagnostic strategies. Sensitivity and specificity were also assessed regarding the genetic background. RESULTS: The comparative approach showed lower sensitivity compared to the morphologic approach (69.2 and 73.1 vs. 76.9 both readers) but better specificity (95.9 and 95.1 vs. 84.3 and 90.2, respectively). NNE was better in the comparative approach. The readers had more difficulties diagnosing lesions from CDKN2A mutation carriers with red hair colour (RHC) MC1R variants. CONCLUSION: The comparative approach can be useful in high-risk patients to decrease the NNE. Early melanomas in CDKN2A carriers with RHC polymorphisms are more difficult to diagnose even with the comparative approach and benefit from the detection of changes during digital dermoscopy monitoring for early diagnosis.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Dermoscopía , Diagnóstico Precoz , Genotipo , Humanos , Melanoma/diagnóstico , Melanoma/genética , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética
20.
Angew Chem Int Ed Engl ; 60(12): 6791-6798, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33340439

RESUMEN

Hyperpolarization-enhanced magnetic resonance imaging can be used to study biomolecular processes in the body, but typically requires nuclei such as 13 C, 15 N, or 129 Xe due to their long spin-polarization lifetimes and the absence of a proton-background signal from water and fat in the images. Here we present a novel type of 1 H imaging, in which hyperpolarized spin order is locked in a nonmagnetic long-lived correlated (singlet) state, and is only liberated for imaging by a specific biochemical reaction. In this work we produce hyperpolarized fumarate via chemical reaction of a precursor molecule with para-enriched hydrogen gas, and the proton singlet order in fumarate is released as antiphase NMR signals by enzymatic conversion to malate in D2 O. Using this model system we show two pulse sequences to rephase the NMR signals for imaging and suppress the background signals from water. The hyperpolarization-enhanced 1 H-imaging modality presented here can allow for hyperpolarized imaging without the need for low-abundance, low-sensitivity heteronuclei.

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