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Dive into the research topics where A. Pérez-Núñez is active.

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Featured researches published by A. Pérez-Núñez.


American Journal of Neuroradiology | 2012

The Added Value of Apparent Diffusion Coefficient to Cerebral Blood Volume in the Preoperative Grading of Diffuse Gliomas

Amaya Hilario; Ana Ramos; A. Pérez-Núñez; E. Salvador; José María Millán; Alfonso Lagares; Juan Manuel Sepúlveda; P. González-León; Aurelio Hernández-Laín; J. R. Ricoy

Is it worth doing both DWI and perfusion imaging in gliomas? These authors sought to study if ADC and rCBV improved diagnostic accuracy in the preoperative grading of gliomas by assessing 162 patients who later underwent surgery. rCBV was significantly different between grade II and IV and between grade III and IV gliomas, but not between grades II and III. ADC values were significantly different for all 3 grades. Conclusion: ADC measurements were better than rCBV values for distinguishing the grades of gliomas, and the combination of minimum ADC and maximum rCBV improved the diagnostic accuracy of glioma grading. BACKGROUND AND PURPOSE: In cerebral gliomas, rCBV correlates with tumor grade and histologic findings of vascular proliferation. Moreover, ADC assesses water diffusivity and is inversely correlated with tumor grade. In the present work, we have studied whether combined rCBV and ADC values improve the diagnostic accuracy of MR imaging in the preoperative grading of gliomas. MATERIALS AND METHODS: One hundred sixty-two patients with histopathologically confirmed diffuse gliomas underwent DWI and DSC. Mean rCBV and ADC values were compared among the tumor groups with the Student t test or ANOVA. ROC analysis was used to determine rCBV and ADC threshold values for glioma grading. RESULTS: rCBV had significantly different values between grade II and IV gliomas and between grade III and IV tumors, but there were no significant differences between grade II and III gliomas (P > .05). Grade II and III tumors also did not differ when astrocytomas, oligodendrogliomas, and oligoastrocytomas were considered separately. ADC values were significantly different for all 3 grades. The ADC threshold value of 1.185 × 10−3 mm2/s and the rCBV cutoff value of 1.74 could be used with high sensitivity in the characterization of high-grade gliomas. The area under the ROC curve for the maximum rCBV and minimum ADC was 0.72 and 0.75, respectively. The combination of rCBV and ADC values increased the area under the ROC curve to 0.83. CONCLUSIONS: ADC measurements are better than rCBV values for distinguishing the grades of gliomas. The combination of minimum ADC and maximum rCBV improves the diagnostic accuracy of glioma grading.


Acta Neurochirurgica | 2004

Lhermitte-Duclos disease and Cowden disease: clinical and genetic study in five patients with Lhermitte-Duclos disease and literature review

A. Pérez-Núñez; Alfonso Lagares; J. Benítez; M. Urioste; R.D. Lobato; J. R. Ricoy; Ana Ramos; Pedro Gonzalez

SummaryBackground. Lhermitte-Duclos Disease (LDD) is an infrequent cerebellar disorder characterized by focal or diffuse enlargement of cerebellar folia presenting as a slowly growing mass in the posterior fossa. Over the past decade its association with Cowden disease (CD) has been recognized with increasing frequency. This latter disease is a genetic condition leading to the presence of multiple hamartomas and neoplasias which affect mainly the skin, thyroid, breast and genito-urinary and gastro-intestinal tracts. It has even been hypothesized that LDD and CD constitute a single entity. This work is aimed to analyse to what extent this association was present in patients treated for LDD at our institution. Method. We reviewed the medical records of five patients and performed clinical studies for CD manifestations, among them, genetic investigation for PTEN mutations. The International Cowden Consortium Criteria were applied for the diagnosis of CD. Findings. Four of the five patients treated for LDD were also diagnosed of CD. The genetic study found PTEN mutations in two of them. Interpretation. LDD has been found to be closely related to CD in this series, in accordance with previous literature. However, the absence of CD diagnosis in one of the patients led us to suggest that, despite the strong association between these two diseases, LDD can also appear as an isolated condition.


American Journal of Neuroradiology | 2014

A Prognostic Model Based on Preoperative MRI Predicts Overall Survival in Patients with Diffuse Gliomas

Amaya Hilario; Juan Manuel Sepúlveda; A. Pérez-Núñez; E. Salvador; José María Millán; Aurelio Hernández-Laín; V. Rodriguez-Gonzalez; Alfonso Lagares; Ana Ramos

BACKGROUND AND PURPOSE: Diffuse gliomas are classified as grades II–IV on the basis of histologic features, with prognosis determined mainly by clinical factors and histologic grade supported by molecular markers. Our aim was to evaluate, in patients with diffuse gliomas, the relationship of relative CBV and ADC values to overall survival. In addition, we also propose a prognostic model based on preoperative MR imaging findings that predicts survival independent of histopathology. MATERIALS AND METHODS: We conducted a retrospective analysis of the preoperative diffusion and perfusion MR imaging in 126 histologically confirmed diffuse gliomas. Median relative CBV and ADC values were selected for quantitative analysis. Survival univariate analysis was made by constructing survival curves by using the Kaplan-Meier method and comparing subgroups by log-rank probability tests. A Cox regression model was made for multivariate analysis. RESULTS: The study included 126 diffuse gliomas (median follow-up of 14.5 months). ADC and relative CBV values had a significant influence on overall survival. Median overall survival for patients with ADC < 0.799 × 10−3 mm2/s was <1 year. Multivariate analysis revealed that patient age, relative CBV, and ADC values were associated with survival independent of pathology. The preoperative model provides greater ability to predict survival than that obtained by histologic grade alone. CONCLUSIONS: ADC values had a better correlation with overall survival than relative CBV values. A preoperative prognostic model based on patient age, relative CBV, and ADC values predicted overall survival of patients with diffuse gliomas independent of pathology. This preoperative model provides a more accurate predictor of survival than histologic grade alone.


Neurocirugia | 2005

Utilidad de la TAC secuencial y la monitorización de la presión intracraneal para detectar nuevo efecto masa intracraneal en pacientes con traumatismo craneal grave y lesión inicial Tipo I-II

R.D. Lobato; J.F. Alén; A. Pérez-Núñez; R. Alday; P.A. Gómez; B. Pascual; Alfonso Lagares; P. Miranda; I. Arrese; Ariel Kaen

Utilidad de la TAC secuencial y la monitorizacion de la presion intracraneal para detectar nuevo efecto masa intracraneal en pacientes con traumatismo craneal grave y lesion inicial Tipo I-II


Neurocirugia | 2004

Meningiomas of the basal posterior fossa. Surgical experience in 80 cases

R.D. Lobato; Pedro Gonzalez; R. Alday; Ana Ramos; Alfonso Lagares; J.F. Alén; J.C. Palomino; P. Miranda; A. Pérez-Núñez; I. Arrese

INTRODUCTION Despite recent improvements in microsurgical and radiotherapy techniques, treatment of basal posterior fossa meningiomas still carries an elevated risk of morbidity. We present our results in a series of patients with this type of tumor and review the recent literature looking for the results obtained with different approaches and the new tendencies and algorithms proposed for managing these challenging lesions. MATERIAL AND METHODS We analyzed retrospectively the clinical presentation and outcome of 80 patients consecutively operated between 1979 and 2003 for basal posterior fossa meningioma (foramen magnum tumors excluded). All patients had preoperative CT scans and the majority MRI studies. A total of 114 operations were performed including two-stage operations, reoperation for recurrence, CSF diversion, and XII-VII anastomosis. The most commonly used approaches were lateral suboccipital retrosigmoid, subtemporal-transtentorial, frontotemporal pterional and supra-infratentorial presigmoid. Thirteen patients received postoperative radiotherapy. RESULTS There were 59 (73.7%) women and 21 men (mean age = 51.5 years; range = 18-78 yrs). Most common presenting symptoms were cranial nerve dysfunction, gait disturbances and intracranial hypertension. The mean duration of symptoms was 2.9 years. 70% of the tumors were over 3 cm in size. Fifty patients (62.5%) had a complete resection, 22 (27.5%) subtotal resection (> 90% tumor volume removed), and 8 (10%) only partial resection. Postoperative complications included hematoma, CSF leak, and infection. Fifty four (67.5%) patients developed new or increased cranial nerve deficits and 12.5% somatomotor, somatosensory or cerebellar deficits immediately after surgery with subsequent improvement in most cases. Following initial surgery 67 patients made a good recovery, 10 developed variable degrees of disability and 3 died. Eleven patients died later in the course for tumor recurrence with or without reoperation, malignant meningioma or unrelated causes. There were 9 recurrences in the subgroup of patients having complete resection initially (mean follow-up = 8.6 years). The majority of patients having initial subtotal or partial resections have been managed without reoperation during a mean follow-up period of 6.5 years (radiosurgery and/or observation). DISCUSSION AND CONCLUSION Current microsurgical and radiotherapy techniques allow either a cure or an acceptable control of basal posterior fossa meningiomas. In patients with tumor invasion of the cavernous sinus, extracranial extension, violation of the arachnoidal membranes in front of the brainstem, or encasement and infiltration of major arteries, a subtotal excision seems preferable followed by observation and/ or radiosurgical treatment. Apart from the patients age and the clinical presentation (symptomatic or not), the size and secondary extensions of the tumor must be taken into account for planning treatment in the individual patient.


Acta Neurochirurgica | 2007

Dural arteriovenous fistula presenting as brainstem ischaemia

Alfonso Lagares; A. Pérez-Núñez; R. Alday; Ana Ramos; J. Campollo; R.D. Lobato

SummaryDural arteriovenous fistulas presenting with ascending myelopathy are characterised by the presence of an abnormal retrograde drainage through spinal veins. The authors present a case of cranial dural arteriovenous fistula causing brainstem dysfunction secondary to venous hypertension, treated by surgical interruption of the pial venous drainage which resulted in complete clinical and radiological resolution of the brainstem lesion.


Acta Neurochirurgica | 2005

Lymphocytic hypophysitis with cystic MRI appearance

A. Pérez-Núñez; P. Miranda; I. Arrese; Pedro Gonzalez; Ana Ramos; R.D. Lobato

SummaryLymphocytic hypophysitis (LH) is an infrequent primary inflammatory disorder, which is usually diagnosed after surgery for lesions suspected to be pituitary adenomas. Some radiological features have been described that may allow a preoperative diagnosis, such as a symmetric enlargement of the gland with diffuse contrast enhancement extending to the basal hypothalamus in a tongue-like fashion. We describe the case of a patient with LH presenting with the MR imaging of a cystic lesion with ring contrast enhancement. It seems that this appearance in imaging studies is not unusual, and should be considered among the features suggesting this disease in an appropriate clinical context.


Neurocirugia | 2009

Intradural extramedullary spinal hydatidosis: case report

Ariel Kaen; Alfonso Lagares; A. Pérez-Núñez; Juan J. Rivas; Ana Ramos; R.D. Lobato

The parasitic tapeworm Echinococcus granulosis causes hydatid disease, which is rarely encountered in nonendemic regions. It is a progressive disease with serious morbidity risks. Rarely, these cysts are found in the spine. They are mainly found epidurally, originating from direct extension from pulmonary, abdominal or pelvic infestation. Nevertheless, the main mechanism for intradural involvement is not yet clear. Antihelminthic treatment should be administered for a long period following early decompressive surgery. We report a case of recurrent hydatid disease that presented unusual intradural dissemination. Prognosis for spinal hydatid disease remains very poor and comparable to that of a malignant neoplasm.


Neurocirugia | 2006

Resonancia magnética en trauma craneal moderado y grave: estudio comparativo de hallazgos en TC y RM. Características relacionadas con la presencia y localización de lesión axonal difusa en RM ☆

Alfonso Lagares; R. Alday; A. Pérez-Núñez; I. Arrese; J.F. Alén; B. Pascual; Ariel Kaen; P.A. Gómez; R.D. Lobato; Ana Ramos; Federico Ballenilla

Resumen Introduccion La TC craneal ha sido el metodo mas extendido en la evaluacion de enfermos que han sufrido trauma craneal. Sin embargo, es poco sensible en la identificacion de lesion axonal difusa y lesiones en fosa posterior. La RM craneal es una prueba potencialmente mas sensible pero de dificil realizacion en estos enfermos, hecho que ha impedido la generalizacion de su uso. Objetivos Comparar la capacidad de identificacion de lesiones intracraneales postraumaticas por parte de las dos pruebas diagnosticas en enfermos con TCE grave y moderado, y determinar que caracteristicas radiologicas en la TC se asocian a la presencia de LAD en RM y su gravedad clinica. Material y metodos Se incluyen en el estudio 100 enfermos con TCE moderado y grave a los que se ha realizado RM craneal dentro de los primeros 30 dias tras el trauma craneal. Se recogieron todas las variables clinicas potencialmente relacionadas con el pronostico de los enfermos, asi como los datos del TC inicial segun la clasificacion de Marshall y cols. La RM fue evaluada de manera ciega por dos neurorradiologos que ignoraban al resultado de la TC inicial y la situacion clinica inicial del paciente. Se recogieron todas las lesiones que presentaban, asi como su clasificacion segun la clasificacion de lesiones asociadas con LAD, descrita por Adams. Se compararon los hallazgos en TC y RM, evaluando la sensibilidad de cada prueba con respecto a los diferentes hallazgos. Se estudiaron los hallazgos relacionados con la presencia de LAD en RM, mediante estudio univariable, usando la prueba de χ2 y correlaciones simples. Resultados La RM es mas sensible que la TC para las lesiones en sustancia blanca cerebral, cuerpo calloso y tronco. Ademas, detecta mayor numero de contusiones. La presencia de lesion axonal difusa depende del mecanismo de produccion del trauma, siendo mas frecuente en traumas de mayor energia, sobre todo en los accidentes de trafico, bien sea con automovil o moto/bici. En cuanto a las caracteristicas radiologicas asociadas a LAD la mas claramente relacionada es la hemorragia intraventricular. La presencia de dano cada vez mas profundo y mayor puntuacion en la escala de Adams se asocia a menor puntuacion en la GCS y GCS motora, y por consiguiente peor nivel de conciencia y mayor gravedad del trauma inicial, confirmando el modelo de Ommaya.


Neurosurgery | 2005

Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing syndrome treated with microvascular decompression of the trigeminal nerve: Case report

Alfonso Lagares; P.A. Gómez; A. Pérez-Núñez; R.D. Lobato; Ana Ramos

OBJECTIVE AND IMPORTANCE:Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing syndrome is a very rare disorder characterized by short-lasting neuralgiform unilateral pain affecting the orbital-periorbital area and associated with autonomic phenomena consisting mainly of conjunctival injection, tearing, and rhinorrhea. Treatment of this condition is difficult; many drugs and surgical procedures have been tried with variable results. In the literature, two cases have been described with short-term response to microvascular decompression of the trigeminal root. We present the case of a patient with short-lasting unilateral neuralgiform headache with conjunctival injection and tearing syndrome who remains asymptomatic 2 years after microvascular decompression. CLINICAL PRESENTATION:A 56-year-old woman was referred to our clinic because she had experienced pain in the distribution of the first left trigeminal branch during the previous 2 years. She experienced paroxysms lasting from a few seconds to 1 to 2 minutes superimposed over a dull sensation of pain involving the same territory. The paroxysms had no refractory period and were triggered by touching the eye or the left side of the face, chewing, yawning, washing her hair, and even by light. Although the paroxysms were triggered by light touch or chewing, she was able to talk or touch herself while having the paroxysm. During pain attacks, she experienced tearing and ipsilateral conjunctival injection, eyelid edema and rhinorrhea, as well as intense photophobia. A magnetic resonance imaging scan revealed a vascular structure distorting and compressing the trigeminal root. INTERVENTION:The patient underwent microvascular decompression of the trigeminal root. At surgery, there was clear compression of the trigeminal root by a superior cerebellar artery loop that was resolved by interposing a Teflon patch. The patient awoke from the operation without pain, and all the accompanying signs and symptoms, such as photophobia, disappeared. The postoperative course was uneventful, and 2 years after treatment, the patient remains asymptomatic. CONCLUSION:Microvascular decompression could be an alternative therapeutic approach to this rare syndrome.

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Alfonso Lagares

Complutense University of Madrid

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R.D. Lobato

Complutense University of Madrid

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Ana Ramos

Complutense University of Madrid

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R. Alday

Complutense University of Madrid

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Aurelio Hernández-Laín

Complutense University of Madrid

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P.A. Gómez

Complutense University of Madrid

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Juan Manuel Sepúlveda

University of Texas MD Anderson Cancer Center

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Amaya Hilario

Complutense University of Madrid

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J.F. Alén

Complutense University of Madrid

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