[Anterior odontoid screw fixation using intra-operative cone-beam computed tomography and navigation]. / Atornillado anterior de la odontoides empleando tomografía computarizada de haz cónico intraoperatorio y navegación.

OBJECTIVE: The purpose of this study was to asses the value of intraoperative cone-beam CT (O-arm) and stereotactic navigation for the insertion of anterior odontoid screws. MATERIALS AND METHODS: this was a retrospective review of patients receiving surgical treatment for traumatic odontoid fractures during a period of 18 months. Procedures were guided with O-arm assistance in all cases. The screw position was verified with an intraoperative CT scan. Intraoperative and clinical parameters were evaluated. Odontoid fracture fusion was assessed on postoperative CT scans obtained at 3 and 6 months' follow-up RESULTS: Five patients were included in this series; 4 patients (80%) were male. Mean age was 63.6 years (range 35-83 years). All fractures were acute type ii odontoid fractures. The mean operative time was 116minutes (range 60-160minutes). Successful screw placement, judged by intraoperative computed tomography, was attained in all 5 patients (100%). The average preoperative and postoperative times were 8.6 (range 2-22 days) and 4.2 days (range 3-7 days) respectively. No neurological deterioration occurred after surgery. The rate of bone fusion was 80% (4/5). CONCLUSION: Although this initial study evaluated a small number of patients, anterior odontoid screw fixation utilizing the O-arm appears to be safe and accurate. This system allows immediate CT imaging in the operating room to verify screw position.

[Retro-odontoid pseudotumor in diffuse idiopathic skeletal hyperostosis]. / Pseudotumor retroodontoideo en un paciente con hiperostosis esquelética idiopática difusa.

Retro-odontoid pseudotumors are lesions caused by inflammatory granulation or reactive soft tissue hypertrophy from chronic atlantoaxial subluxation. However, one-third of the cases reported in the medical literature did not show atlantoaxial instability clearly. The authors present the case of a 76-year-old man previously diagnosed with diffuse idiopathic skeletal hyperostosis who presented with severe progressive myelopathy. A magnetic resonance imaging of his cervical spine revealed a retro-odontoid predural mass, which caused a severe compression of the cervical spinal cord. The patient underwent a posterior laminectomy of the atlas and an occipitocervical fusion. After surgery, the pseudotumor was considerably smaller and the neurological symptoms improved.

[Cervical spine osteochondroma presenting with torticollis and hemiparesis]. / Osteocondroma de la columna cervical provocando tortícolis y hemiparesia.

Osteochondromas are slow-growing benign bone tumors that are located frequently in the long bones. Approximately 1-4% of them occur in the spine. Solitary spinal osteochondromas may produce a wide variety of symptoms depending on their location and relationship to associated structures. We report a case of a 74-year old woman who was admitted to our hospital with complaints of progressive left hemibody weakness and cervicalgia. Neurological examination disclosed mild left-sided hemiparesis and left torticollis. Computed tomography and magnetic resonance imaging of the cervical spine revealed an expansive lesion affecting the left C3-C4 facet joint. The patient underwent a posterior C3 and C4 hemilaminectomy, complete excision of the lesion and instrumented posterior cervical fixation. Histological examination confirmed the diagnosis of osteochondroma. After surgery her symptoms improved progressively with no neurological sequels.

[Cryptococcal meningitis associated with hydrocephalus in an immunocompetent patient].

Cryptococcal meningitis is an infrequent infection with high morbidity and mortality. Its presentation in immunocompetent patients is rare. We present the case of a 67-year-old male who was admitted for subacute symptoms of gait disturbance and urinary incontinence. Neurological examination revealed inability to stand and memory impairment. Cranial imaging showed obstructive tetraventricular hydrocephalus with areas of gliosis in the cerebellar peduncles. Endoscopic treatment of hydrocephalus was performed and cerebrospinal fluid samples taken revealing the growth of Cryptococcus neoformans. The patient improved with the endoscopic treatment and after completing intravenous antifungal therapy with liposomal amphotericin B and fluconazole for ten weeks. Antifungals are used to treat cryptococcal meningitis in immunocompetent patients. On rare occasions, it presents with hydrocephalus, a situation that requires surgical treatment using cerebrospinal fluid diversions or endoscopic techniques.

[Anterior cerebral artery aneurism presenting as a third ventricular mass and hydrocephalus. Case report]. / Aneurisma de la arteria cerebral anterior que se presenta como masa del tercer ventrículo e hidrocefalia. A propósito de un caso.

Aneurysms which appear as third ventricular masses are uncommon; most are giant aneurysms arising from the basilar apex. We present the case of a 67-year-old male who was admitted to hospital with a 4-week history of gait instability, urinary incontinence and progressive visual loss. A cranial computed tomography scan revealed a hyperdense mass in the third ventricle with triventricular dilatation. Cerebral magnetic resonance imaging, magnetic resonance-angiography and conventional angiography identified this lesion as a partially thrombosed aneurysm of the anterior cerebral artery. To our knowledge, this is the first report of an anterior cerebral artery aneurysm with these clinical and radiological features.

[Posterior lumbar fusion using the O-arm surgical imaging system: initial experience]. / Fijación lumbar posterior empleando el sistema de imagen quirúrgica O-arm: experiencia inicial.

OBJECTIVES: The use of transpedicular screw fixation has been widely accepted for the treatment of degenerative and traumatic pathology of the lumbar spine. Complications of spinal instrumentation can be serious. Screw misplacement can result in unintended durotomy, nerve root and/or cauda equina injury. In comparison to fluoroscopy-assisted screw placement, computer-assisted image guidance has been shown to achieve overall higher rates of accuracy. The O-arm is able to obtain computed tomography (CT)-type images with multiplanar reconstruction. In this study we evaluated a cohort of patients who underwent posterior lumbar fusion with pedicle screws utilizing the O-arm imaging system. METHODS: A retrospective review of 40 consecutive patients who underwent posterior lumbar fusion surgery with O-arm utilization, was performed. The study population included 14 males and 26 females. Age range was 39-85 years with an average of 63.8 years. Twenty one patients had degenerative lumbar stenosis (52.5%) and 19 had spondylolisthesis (47.5%). Intraoperative CT-images were obtained. The mean time for surgery and screw placement was assessed. RESULTS: A total of 252 pedicle screws were sited using O-arm navigation system, with a mean of 6.3 screws per patient (range 4-10). On the basis of intraoperative CT, 3 screws were redirected, representing a 98.81% accuracy rate. The mean duration of surgery was 157.2 (90-240) minutes and the mean time for screw placement was 7.13 (3.08-15) minutes per screw. Three patients (7.5%) developed superficial wound infections which were treated conservatively. No patients required a return to the operating room because of screw malposition. CONCLUSION: The use of intraoperative O-arm imaging system with computer-assisted navigation significantly increases the surgical accuracy and safety of pedicle screw placement in lumbar fusion surgery.

Craniofacial fibrous dysplasia and aneurismal bone cyst in a patient with McCune-Albright syndrome. A case report and review of the literature.

McCune-Albright syndrome (MAS) is a rare heterogeneous genetic disorder that is characterized by a triad of polyostotic fibrous dysplasia (FD), café au lait spots (CAL), and multiple hyperfunctional endocrinopathies. In general, it is diagnosed clinically. From the triads, 2 of the findings are enough to make the diagnosis. Craniofacial fibrous dysplasia is a term that is used to describe the fibrous dysplasia, which was localized at the craniofacial skeleton and is common in MAS patients. Aneurysmal bone cyst (ABC) is a rare non-neoplastic bone lesion that involves mostly the long bones and vertebrae and may occur very rarely in the craniofacial bones. ABCs may occur as secondary bony pathologies in association with various benign and malignant bone tumors and with fibrous dysplasia. Secondary ABC occurring in craniofacial FD is extremely rare. We present the case of a 21-year-old patient treated at our center for a right orbital aneurysmal bone cyst associated with MAS and provide a review of the relevant literature.

Paravertebral lipomatous ganglioneuroma with intraspinal extension. Case report and literature review. / Ganglioneuroma lipomatoso paravertebral con extensión intraespinal. Descripción de un caso y revisión de la literatura.

Lipomatous ganglioneuromas are a rare variant of ganglioneuromas characterized by a mature adipocytic component admixed with a conventional ganglioneuroma component. We present the case of a 34 year old patient with a paravertebral right lesion L1-L4 with intraspinal extension and secondary neurological deficit, who underwent surgery in our hospital. The pathological anatomy showed a yellowish encapsulated neoplasm, which under microscopic evaluation showed areas of ganglioneuroma admixed with areas of mature fat. In the follow up, the patient was asymptomatic, had recovered paresis in the right lower extremity and in the last image control did not present data of lesion recurrence. Fewer than 10 cases of lipomatous ganglioneuromas have been reported in the literature, being this the first paravertebral case wih intraspinal extension and with neurological deficit, hence the interest of this work.

Choroid plexus papilloma of the third ventricle. A case report. / Papiloma del plexo coroideo del tercer ventrículo. Descripción de un caso.

Choroid plexus papilloma is an uncommon tumour of the central nervous system, accounting for less than 1% of all intracranial neoplasm. The usual locations are the lateral ventricle in infants and children and the fourth ventricle in adults. The third ventricle is a rare location, with few cases reported in the literature. We describe the case of a 3-month-old boy who was admitted to our centre with signs of raised intracranial pressure. Neuroimaging studies showed a third ventricular mass with associated hydrocephalus. The patient underwent complete tumour removal through a transfrontal approach and ventriculo-peritoneal shunt surgery. Postoperative course of the child was uneventful and follow-up magnetic resonance imaging revealed no residual tumour. Histopathology of the resected lesion confirmed the diagnosis of choroid plexus papilloma. We discuss the clinical, radiological and histological features of this infrequent type of tumours.

Meningitis criptocócica asociada a hidrocefalia en un paciente inmunocompetente / Cryptococcal meningitis associated with hydrocephalus in an immunocompetent patient

La meningitis criptocócica es una infección infrecuente y con alta morbimortalidad, cuya presentación en pacientes inmunocompetentes es excepcional. Presentamos el caso de un varón de 67 años que ingresó por un cuadro subagudo de alteración de la marcha e incontinencia urinaria. El examen neurológico reveló incapacidad para mantenerse en pie y deterioro de la memoria. Las pruebas de imagen craneales mostraron hidrocefalia tetraventricular obstructiva con áreas de gliosis en los pedúnculos cerebelosos. Se realizó tratamiento endoscópico de la hidrocefalia, con toma de muestras de líquido cefalorraquídeo en las que se observó crecimiento de Cryptococcus neoformans. El paciente mejoró con el tratamiento endoscópico y tras completar la terapia antifúngica intravenosa con anfotericina B liposomal y fluconazol durante diez semanas. La meningitis criptocócica en pacientes inmunocompetentes se trata con antifúngicos. En raras ocasiones se presenta con hidrocefalia, situación que requiere tratamiento quirúrgico mediante derivaciones del líquido cefalorraquídeo o técnicas endoscópicas. (AU)

Cryptococcal meningitis is an infrequent infection with high morbidity and mortality. Its presentation in immuno-competent patients is rare.We present the case of a 67-year-old male who was admitted for subacute symptoms of gait disturbance and urinary incontinence. Neurological examination revealed inability to stand and memory impairment. Cranial im-aging showed obstructive tetraventricular hydrocephalus with areas of gliosis in the cerebellar peduncles. Endo-scopic treatment of hydrocephalus was performed and cerebrospinal fluid samples taken revealing the growth of Cryptococcus neoformans. The patient improved with the endoscopic treatment and after completing intravenous antifungal therapy with liposomal amphotericin B and flu-conazole for ten weeks.Antifungals are used to treat cryptococcal meningitis in immunocompetent patients. On rare occasions, it presents with hydrocephalus, a situation that requires surgical treat-ment using cerebrospinal fluid diversions or endoscopic techniques. (AU)

Papillary glioneuronal tumor. A case report. / Tumor glioneuronal papilar. Descripción de un caso.

Papillary glioneuronal tumor (PGNT) is a recently described central nervous system neoplasm. In 2007, the World Health Organization classified this tumor as a grade I neuronal-glial neoplasm. Patients are usually juvenile and young adults who commonly present with headache or seizures. We report a case of a 13-year-old boy that was related to our hospital after suffering a mild head injury result of an automobile accident. Emergent CT scan showed a right hypointense temporo-occipital lesion. MRI confirmed the presence of a lesion suggestive of a primary brain tumor. The patient underwent total resection of the tumor, followed by an uneventful recovery. Pathological analysis of the lesion revealed characteristic pseudopapillary structure with astrocytes and neurons, compatible with PGNT. We discuss the clinical, Radiological and histological features of this infrequent type of tumors.

Linfoma primario de base de cráneo presentándose como oftalmoplejia aguda / Primary skull base lynphoma presenting as acute ophtalmoplegia

Primary Skull base lymphoma (PSBL) represents a rare manifestation of extranodal lymphoma. Aggressive non-Hodgkin´s lymphoma such as diffuse large B-cell lymphoma, constitute the most commonly encountered subtype of PBSL. We report the case of a 70-year-oldwoman with acute diplopia and ptosis of the right eye. Neurological examination showed palsy of right III, IV and VI cranial nerves. Brain imaging studies showed a lesion showed invading the floor of the sella turcica, both cavernous sinuses, the clivus and part of the sphenoid sinus. The patient underwent endonasal endoscopic resection of the lesion. The histological diagnosis was diffuse large B-cell lymphoma. No systemic disease was found on staging the patient. (AU)

El linfoma primario de base de cráneo (LPBC) representa una variante poco frecuente del linfoma extranodal. Los linfomas no-Hodgkin agresivos, tales como el linfoma difuso de células grandes B son el subtipo más frecuente que se presentan como LPBC. Describimos el caso de una paciente mujer de 70 años que acude a nuestro centro con una clínica aguda de diplopía y posterior ptosis del ojo derecho. En la exploración neurológica se constató parálisis de III, IV y VI pares derechos. Los estudios de imagen cerebral mostraron una lesión que invadía el suelo de la silla turca, ambos senos cavernosos, el clivus y parte del seno esfenoidal. Se realizó una exéresis endoscópica endonasal de la lesión. El examen histológico de la lesión fue compatible con un linfoma difuso de células grandes B. No se constató enfermedad sistémica en los estudios de extensión. (AU)

Obesity-hypoventilation syndrome: increased risk of death over sleep apnea syndrome.

AIM: To study whether mortality and cardiovascular morbidity differ in non-invasive ventilation (NIV)-treated patients with severe obesity-hypoventilation syndrome (OHS) as compared with CPAP-treated patients with obstructive sleep apnea syndrome (OSAS), and to identify independent predictors of mortality in OHS. MATERIAL AND METHODS: Two retrospective cohorts of OHS and OSAS were matched 1:2 according to sex, age (± 10 year) and length of time since initiation of CPAP/NIV therapy (± 6 months). RESULTS: Three hundred and thirty subjects (110 patients with OHS and 220 patients with OSAS) were studied. Mean follow-up time was 7 ± 4 years. The five year mortality rates were 15.5% in OHS cohort and 4.5% in OSAS cohort (p< 0.05). Patients with OHS had a 2-fold increase (OR 2; 95% CI: 1.11-3.60) in the risk of mortality and 1.86 fold (OR 1.86; 95% CI: 1.14-3.04) increased risk of having a cardiovascular event. Diabetes, baseline diurnal SaO2 < 83%, EPAP < 7 cmH2O after titration and adherence to NIV < 4 hours independently predicted mortality in OHS. CONCLUSION: Mortality of severe OHS is high and substantially worse than that of OSAS. Severe OHS should be considered a systemic disease that encompasses respiratory, metabolic and cardiovascular components that require a multimodal therapeutic approach.

Displasia fibrosa craneofacial y quiste óseo aneurismático en una paciente con síndrome de McCune-Albright. Presentación de un caso y revisión de la literatura / Craniofacial fibrous dysplasia and aneurismal bone cyst in a patient with McCune-Albright syndrome. A case report and review of the literature

El síndrome de McCune-Albright (SMA) es un trastorno genético heterogéneo que se caracteriza por la tríada de displasia fibrosa (DF) poliostótica, manchas café con leche y múltiples endocrinopatías hiperfuncionales. En general, se diagnostica clínicamente. De la tríada, 2 de los hallazgos son suficientes para hacer el diagnóstico. La DF craneofacial es un término que se usa para describir la displasia fibrosa, que se localizaba en el esqueleto craneofacial y es común en pacientes con SMA. El quiste óseo aneurismático (QOA) es una lesión ósea no neoplásica infrecuente que afecta principalmente a los huesos largos y las vértebras, y puede ocurrir muy raramente en los huesos craneofaciales. Los QOA pueden ocurrir como enfermedades óseas secundarias en asociación con varios tumores óseos benignos y malignos y con displasia fibrosa. El QOA secundario que ocurre en la DF craneofacial es excepcional. Presentamos el caso de una paciente de 21 años tratada en nuestro centro de un quiste óseo aneurismático orbitario derecho asociado a SMA y realizamos una revisión de la literatura relevante (AU)

McCune-Albright syndrome (MAS) is a rare heterogeneous genetic disorder that is characterized by a triad of polyostotic fibrous dysplasia (FD), café au lait spots (CAL), and multiple hyperfunctional endocrinopathies. In general, it is diagnosed clinically. From the triads, 2of the findings are enough to make the diagnosis. Craniofacial fibrous dysplasia is a term that is used to describe the fibrous dysplasia, which was localized at the craniofacial skeleton and is common in MAS patients. Aneurysmal bone cyst (ABC) is a rare non-neoplastic bone lesion that involves mostly the long bones and vertebrae and may occur very rarely in the craniofacial bones. ABCs may occur as secondary bony pathologies in association with various benign and malignant bone tumors and with fibrous dysplasia. Secondary ABC occurring in craniofacial FD is extremely rare. We present the case of a 21-year-old patient treated at our center for a right orbital aneurysmal bone cyst associated with MAS and provide a review of the relevant literature (AU)

[Subependymoma of the lateral ventricle. A case report]. / Subependimoma del ventriculo lateral. A proposito de un caso.

INTRODUCTION. Intracranial subependymomas are rare, slow-growing, noninvasive, benign tumors. They are most often located in the fourth ventricle. Most of these tumors are discovered incidentally during autopsy. Routine medical checkups using neuroimaging techniques have increased their diagnosis. Subependymomas may present with symptoms related to cerebrospinal fluid obstruction or mass effect. CASE REPORT. A 52-year-old man presented with severe headache and mental deterioration with memory disturbances and bradypsychia. Computed tomography and magnetic resonance imaging revealed a mass in the right lateral ventricle causing obstructive hydrocephalus. The tumour was totally removed through a right frontal transcortical approach. Histological examination showed a typical subependymoma. A complete neurological recovery was achieved after surgery. CONCLUSIONS. Subependymomas are rare low-grade glial neoplasm that commonly arise in the ventricular system. They have a low-proliferative potential but in these locations they can cause symptomatic hydrocephalus. Surgical removal of the mass and the restoration of the normal cerebrospinal fluid pathways constitute the optimal management strategy.

Pneumosinus dilatans frontal en niña de 9 años. Presentación de un caso y revisión de la literatura / Pneumosinus dilatans frontalis in 9-year-old child. Case report and review of the literature

El pneumosinus dilatans (PD) representa una enfermedad infrecuente en adultos, y verdaderamente excepcional en niños. Existen aproximadamente 100 casos descritos en adultos en la literatura, de los cuales menos de 10 han sido descritos en chicos con edades comprendidas entre los 12-16 años, y ninguno en niños. Se describe como una aireación anómala de un seno paranasal más allá del límite normal del hueso con mucosa normal. Puede producir alteraciones cosméticas o funcionales. Su etiología permanece siendo desconocida. Afecta fundamentalmente al seno frontal. Presentamos el caso de una niña de 9 años con diagnóstico de PD frontal desde los 3 años, intervenida quirúrgicamente por alteración cosmética relevante. La intervención quirúrgica fue practicada mediante abordaje endocraneal a través de incisión coronal con resultados cosméticos excelentes (AU)

Pneumosinus dilatans (PD) is a rare condition in adults and truly exceptional in children. There are approximately 100 reported cases in adults, with fewer than 10 in adolescents aged 12-16, and none in children. It is described as a benign airfilled expansion of a paranasal sinus beyond the normal osseous boundaries. It could result in cosmetic and functional complications. The precise etiology of the condition remains unknown. The frontal sinus is the most commonly affected. It is reported the case of a 9-year-old female diagnosed with PD frontalis at 3 years of age. She underwent surgery for significant cosmetic alterations. The surgical plan included an intracranial approach through coronal incision with excellent cosmetic results (AU)