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1.
Sensors (Basel) ; 22(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36501887

RESUMEN

In this study, principal component analysis and k-means clustering (PCAKM) methods for synthetic aperture radar (SAR) data are analyzed to reduce the sensitivity caused by changes in the parameters and input images of the algorithm, increase the accuracy, and make an improvement in the computation time, which are advantageous for scoring in the follow-up plan. Although there are many supervised methods described in the literature, unsupervised methods may be more appropriate in terms of computing time, data scarcity, and explainability in order to supply a trustworthy system. We consider the PCAKM algorithm, which is used as a benchmark method in many studies when making comparisons. Error metrics, computing times, and utility functions are calculated for 22 modified PCAKM regarding difference images and filtering methods. Various images with different characteristics affect the results of the configurations. However, it is evident that the PCAKM becomes less sensitive and more accurate for both the overall results and image results. Scoring by utilizing these results and other map information is a gap and innovation. Obtaining a change map in a fast, explainable, more robust and less sensitive way is one of the aims of our studies on scoring points in the follow-up plan.


Asunto(s)
Algoritmos , Radar , Análisis por Conglomerados , Análisis de Componente Principal
2.
Am J Med Genet A ; 185(2): 561-565, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33185983

RESUMEN

Clear cell meningioma (CCM) is a rare variant of meningioma. In recent years, an association between cranial and spinal CCMs and germline loss of function mutations in the SMARCE1 gene (SWI/SNF chromatin remodeling complex subunit gene) has been discovered. We report a family with an incidental large spinal clear cell meningioma in a young adult following reflex screening for a germline loss of function pathogenic variant (PV) in the SMARCE1 gene. The index patient's mother and maternal grandfather were both also tested positive presymptomatically for SMARCE1. His mother developed intracranial and spinal meningiomas and his maternal grandfather developed a spinal CCM 4 years following a clear spinal MRI scan which required surgical excision. In this report we particularly emphasize the importance of genetic counseling and screening in siblings, parents and offspring of patients who are diagnosed with intracranial or spinal CCM in the context of SMARCE1 PVs. We recommend brain and spine Imaging screening of asymptomatic SMARCE1 PV carriers at least every 3 years, even if the baseline scan did not show any tumors.


Asunto(s)
Proteínas Cromosómicas no Histona/genética , Proteínas de Unión al ADN/genética , Predisposición Genética a la Enfermedad , Meningioma/genética , Neoplasias de la Columna Vertebral/genética , Adolescente , Niño , Preescolar , Femenino , Asesoramiento Genético , Pruebas Genéticas , Mutación de Línea Germinal/genética , Humanos , Masculino , Meningioma/diagnóstico , Meningioma/diagnóstico por imagen , Meningioma/patología , Linaje , Neoplasias de la Columna Vertebral/diagnóstico , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/patología , Adulto Joven
3.
Acta Neurochir (Wien) ; 157(9): 1595-600, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26144567

RESUMEN

BACKGROUND: The surgical management of cervical brachialgia utilising anterior cervical discectomy and fusion (ACDF) or posterior cervical foraminotomy (PCF) is a controversial area in spinal surgery. Previous studies are limited by utilisation of non-validated outcome measures and, importantly, absence of pre-operative analysis to ensure both groups are matched. The authors aimed to compare the effectiveness of ACDF and PCF using validated outcome measures. To our knowledge, it is the first study in the literature to do this. METHODS: The authors conducted a 5-year retrospective review (2008-2013) of outcomes following both the above procedures and also compared the effectiveness of both techniques. Patients with myelopathy and large central discs were excluded. The main outcome variables measured were the neck disability index (NDI) and visual analogue scores (VAS) for neck and arm pain pre-operatively and again at 2-year follow-up. The Wilcoxon signed-rank test and Student t-tests were used to test differences. RESULTS: A total of 150 ACDFs and 51 PCFs were performed for brachialgia. There was no differences in the pre-operative NDI, VAS neck and arm scores between both groups (p > 0.05). As expected, both ACDF and PCF delivered statistically significant improvement in NDI, VAS-neck and VAS-arm scores. The degree of improvement of NDI, VAS-neck and VAS-arm were the same between both groups of patients (p > 0.05) with a trend favouring the PCF group. In the ACDF group, two (1.3 %) patients needed repeat ACDF due to adjacent segment disease. One patient (0.7 %) needed further decompression via a foraminotomy. In the PCF group one (2.0 %) patient needed ACDF due to persistent brachialgia. CONCLUSIONS: We found both interventions delivered similar improvements in the VAS and NDI scores in patients. Both techniques may be appropriately utilised when treating a patient with cervical brachialgia.


Asunto(s)
Descompresión Quirúrgica/efectos adversos , Discectomía/efectos adversos , Foraminotomía/efectos adversos , Radiculopatía/cirugía , Fusión Vertebral/efectos adversos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Servicio de Cirugía en Hospital/estadística & datos numéricos , Reino Unido
4.
Br J Neurosurg ; 26(6): 919-20, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22577848

RESUMEN

We report a case of Terson's syndrome diagnosed by a CT head scan. The presence of vitreous haemorrhage may not be appreciated clinically in unwell patients with a subarachnoid haemorrhage. Therefore features of vitreous haemorrhage should be sought on CT head imaging in patients presenting with a subarachnoid haemorrhage.


Asunto(s)
Hemorragia Subaracnoidea/terapia , Hemorragia Vítrea/cirugía , Embolización Terapéutica , Humanos , Masculino , Persona de Mediana Edad , Síndrome , Tomografía Computarizada por Rayos X , Vitrectomía
5.
J Neurointerv Surg ; 12(10): 987-992, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31974281

RESUMEN

BACKGROUND AND PURPOSE: Wide-necked bifurcation aneurysms pose a significant challenge to the treating clinician. The Contour Neurovascular System embolization device is a novel tool for the treatment of such intracranial aneurysms. We report on our experience with this device. METHODS: Prospective clinical and radiological data were collected for all patients treated with the Contour device at our center. All our patients were treated on an elective basis. RESULTS: We have treated 11 patients successfully with the Contour device to date. All patients were women with a mean (SD) age of 65.0 (6.4) years. In total, four basilar tip, two internal carotid artery, three middle cerebral artery, one anterior communicating artery, and one superior cerebellar artery aneurysms were treated. At 1-year follow-up, complete occlusion (Raymond Class 1) was seen in 55.56% (5/9) of cases, with 44.44% (4/9) having small neck remnants (Raymond Class 2). One patient declined 1-year catheter angiography and another had no further follow-up due to an unrelated medical condition. For six patients, 2-year radiological follow-up is available and shows stability. At 6 weeks, nine of the 11 patients had a modifed Rankin Scale score of 0, with two patients scoring 1 for headaches. Two patients had thromboembolic events, but there were no complications leading to permanent neurological disability or death. We additionally had three patients where the Contour device was attempted but was unable to be successfully used. CONCLUSION: Initial results are promising although larger case numbers and longer follow-up are necessary to draw further conclusions on the utility and risk profile of this new device.


Asunto(s)
Procedimientos Endovasculares/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Stents Metálicos Autoexpandibles , Anciano , Embolización Terapéutica/efectos adversos , Embolización Terapéutica/métodos , Procedimientos Endovasculares/efectos adversos , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Stents Metálicos Autoexpandibles/efectos adversos , Resultado del Tratamiento
6.
J Neurosurg ; 126(1): 17-28, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27081907

RESUMEN

OBJECTIVE The Woven EndoBridge (WEB) is an innovative new technique for securing cerebral aneurysms. It is designed particularly for wide-necked bifurcation aneurysms that otherwise would be difficult to treat. There is a paucity of follow-up data in the literature due to the novelty of this technique. The authors reviewed their data from cases involving patients treated at Leeds General Infirmary with the WEB device. They assessed the safety and complication risk associated with the device and clinical and radiological follow-up outcomes in their patients. This is, to their knowledge, the first publication to include the new single-layer sphere device (WEB SLS) in addition to the original dual-layer (WEB DL) and the (nonsphere) single-layer (WEB SL) devices. METHODS Data from 22 patients who underwent 25 WEB treatments were analyzed. Of the 25 WEB procedures, 3 were performed on an acute basis, 1 was performed on a semiacute basis, and the remaining 21 were elective. A novel 6-point scoring system called the Leeds WEB aneurysm occlusion scale was created to ensure accurate assessment based on the morphology of the WEB device. Outcome was assessed at follow-up by MR angiography with or without digital subtraction angiography and the modified Rankin Scale (mRS). RESULTS Deployment of the WEB device was successful in 22 (88%) of 25 procedures; 3 (12%) of the attempts at WEB treatment were abandoned. One of the patients in whom treatment was abandoned underwent a successful second attempt. Immediately after the 22 procedures with successful deployment, 4 (18%) of the patients had a complete occlusion of the aneurysm and WEB device; 10 (45%) had varying degrees of occlusion within the WEB device but no aneurysm neck or remnant; 3 (14%) had a neck remnant; and 5 (23%) had an aneurysm remnant. Of the patients with an aneurysm remnant, 1 had a complete aneurysm occlusion at ≥ 3-months follow-up. In total, 6 (27%) patients had a residual aneurysm at ≥ 3-months radiological follow-up. One of these patients was admitted with hydrocephalus secondary to a recurrent aneurysm and later received a second WEB treatment with additional coiling. Only 1 patient developed new neurological symptoms. This patient went from an mRS score of 0 to a score of 1 and had radiological evidence of a thromboembolic event. Two patients showed radiological evidence of a new thromboembolic event on follow-up MRI but were clinically asymptomatic. CONCLUSIONS The WEB has shown itself to be a promising new device with the potential to increase the scope of treatment for difficult wide-necked bifurcation aneurysms. The technique is safe, and short-term results show effective occlusion of complex aneurysms with minimal complications associated with the procedure. Long-term efficacy, however, still needs to be assessed.


Asunto(s)
Procedimientos Endovasculares/métodos , Aneurisma Intracraneal/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Procedimientos Endovasculares/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Datos Preliminares , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
7.
J Rehabil Assist Technol Eng ; 4: 2055668317744999, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-31186944

RESUMEN

INTRODUCTION: Current methods of assessing the outcomes of intracranial aneurysm treatment for aneurysmal subarachnoid haemorrhage are relatively insensitive, and thus unlikely to detect subtle deficits. Failures to identify cognitive and motor outcomes of intracranial aneurysm treatment might prevent delivery of optimal post-operative care. There are also concerns over risks associated with using intracranial aneurysm treatment as a preventative measure. METHODS: We explored whether our kinematic tool would yield useful information regarding motor/cognitive function in patients who underwent intracranial aneurysm treatment for aneurysmal subarachnoid haemorrhage or unruptured aneurysm. Computerised kinematic motor and learning tasks were administered alongside standardised clinical outcome measures of cognition and functional ability, in 10 patients, as a pilot trial. Tests at post-intracranial aneurysm treatment discharge and six-week follow-up were compared to see which measures detected changes. RESULTS: Kinematic tests captured significant improvements from discharge to six-week follow-up, indexed by reduced motor errors and improved learning. Increased Addenbrooke's Cognitive Examination-Revised scores reflected some recovery of memory function for most individuals, but other standardised cognitive measures, functional outcome scores and a psychological questionnaire showed no changes. CONCLUSIONS: Kinematic measures can identify variation in performance in individuals with only slightly improved abilities post-intracranial aneurysm treatment. These measures may provide a sensitive way to explore post-operative outcomes following intracranial aneurysm treatment, or other similar surgical procedures.

8.
Neurosci Lett ; 504(2): 146-150, 2011 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-21945950

RESUMEN

Neurotrophic factors may be used to improve the growth and repair of injured peripheral nerves. In this study we determined the effectiveness of recombinant human growth hormone on peripheral nerve injury in the Wistar rat. The ulnar nerve of the rat was sectioned and its proximal and distal ends were sutured to either end of a silastic tube, with the aim of encouraging regeneration through the tube. 32 ulnar nerve specimens were randomized into two groups: 18 nerves regenerating under the influence of recombinant growth hormone, and 14 nerves regenerating in its absence. The study was performed over a period of 8 weeks and progression of regeneration was assessed with regular surface electroneurography every 1-2 weeks after surgery. In the group receiving recombinant growth hormone, it comprised a significant improvement in the recovery of conduction velocity, and a more gradual increase in the amplitude of motor potential from the fifth week onwards was observed. Histological analysis of study specimens in the recombinant hormone group revealed an improved architecture of the regenerating nerve, a greater density of nerve fibers, and increased myelination with a lesser degree of endoneural fibrosis. Our work demonstrates the positive effect of the administration of recombinant human growth hormone in obtaining significantly improved conduction velocities, and a greater improvement in nerve regeneration from the fifth week of monitoring when compared to the control group. Histological analysis in the group receiving hormone showed acceptable degree of myelination with little granulation tissue and fibrosis.


Asunto(s)
Hormona del Crecimiento/farmacología , Regeneración Nerviosa/efectos de los fármacos , Nervios Periféricos/efectos de los fármacos , Nervio Cubital/efectos de los fármacos , Animales , Axones/efectos de los fármacos , Estimulación Eléctrica , Electrodos Implantados , Electromiografía , Fenómenos Electrofisiológicos , Potenciales Evocados Motores/fisiología , Humanos , Ratas , Ratas Wistar , Proteínas Recombinantes/farmacología , Programas Informáticos , Tendones/fisiología
9.
Lancet Oncol ; 4(4): 207-14, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12681264

RESUMEN

Although substantial progress has been made in the management of Hodgkin's lymphoma during the past 30 years, the development of secondary malignant diseases has emerged as a serious consequence of treatment. In particular, extended follow-up of patients with Hodgkin's disease has revealed an increased risk of breast cancer. We have systematically reviewed all published literature on breast cancer after treatment for Hodgkin's disease and show that high risk is particularly associated with treatment at a young age, mantle radiotherapy, and chemotherapy. Breast cancers in this context differ from sporadic disease because they develop in younger women, are associated with a high incidence of bilateral disease, and are generally located near the midline of the body. The risk of breast cancer is lower in patients who receive newer, combined modality treatments for Hodgkin's disease. In this review we discuss a protocol for formal follow-up and screening of patients who have recovered from Hodgkin's disease to aid early diagnosis and ensure the possibility of effective management.


Asunto(s)
Neoplasias de la Mama/secundario , Enfermedad de Hodgkin/patología , Enfermedad de Hodgkin/terapia , Neoplasias de la Mama/diagnóstico , Terapia Combinada , Femenino , Humanos , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo
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