Significance of the Cerebellopontine Cistern Cross-Sectional Area and Trigeminal Nerve Anatomy in Trigeminal Neuralgia: An Anatomical Study Using Magnetic Resonance Imaging.

AIM: To evaluate the relationship between trigeminal neuralgia (TN) and potential magnetic resonance imaging (MRI)-related measurements in patients with TN. MATERIAL AND METHODS: Retrospective analysis of 104 patients with TN was performed. MRI studies of 98 healthy controls were included in the study to compare the parameters with TN patients’ measurements. MRI measurements of cerebellopontine cistern (CPC) cross-sectional area, trigeminal-pontine angle (TPA) width, and trigeminal nerve cisternal segment length and thickness were assessed on both symptomatic and asymptomatic sides using 1.5T MRI with constructive interference in steady-state sequences. The images were interpreted by two radiologists blinded to the affected sides of the patients. RESULTS: There were significant differences between the symptomatic and asymptomatic sides in terms of mean trigeminal nerve length (8.8 ± 2.34 mm vs. 9.39 ± 2.29 mm; respectively, p=0.001) and thickness (20.9 ± 9.6 mm2 vs. 25 ± 9.98 mm2, respectively; p < 0.001). The median cerebellopontine cistern cross-sectional area was considerably lower on the symptomatic side compared with the asymptomatic side [201 mm2 (interquartile range=93) vs. 224.5 mm2 (interquartile range=77), respectively; p < 0.001]. There were no significant differences between the trigeminal-pontine angle width on either side (38.32 ± 10.38 vs. 38.78 ± 10.9, respectively; p=0.679). There were no statistically significant differences between the right and left sides regarding these parameters in the control group. CONCLUSION: Smaller CPC cross-sectional area, trigeminal nerve length, and trigeminal nerve thickness on MRI were demonstrated to commonly exist on the symptomatic side in patients with TN. We suggest that this narrow space may increase the risk of vascular compression on the nerve.

Developmental venous anomaly of the internal auditory canal in a child with unilateral sensorineural hearing loss--a rare association.

Developmental venous anomalies (DVAs) are extremely unusual in the cerebellopontine angle region and internal auditory canal, and constitute a rare etiology of unilateral sensorineural hearing loss (SNHL) in children. We report, to the best of our knowledge, one of the first documented cases of DVA as a probable cause of unilateral SNHL in a child. Our emphasis is on the radiological features.

Cavernous malformation tumors: a case study and review of the literature.

OBJECTIVE: To summarize the current literature on the surgical management of cavernous malformations of the cerebellopontine angle in accordance with the experience at our institution. METHODS: A systematic literature review on cavernous malformations of the cerebellopontine angle yielded 14 case reports relevant to the disease. In addition, the authors include their own report of a 16-year-old girl with such a lesion cured by surgical resection. RESULTS: The most common clinical signs associated with this tumor are hearing loss (86.7%), followed by facial paresis (53.8%). Symptoms may be rapidly progressive. Cavernous malformations range from isointense to hyperintense to brain on noncontrasted T1 magnetic resonance imaging. In general, outcomes for patients with this tumor are favorable, with most patients cured by surgical resection. CONCLUSION: One of the rarest lesions of the cerebellopontine angle is a cavernous malformation. An understanding of the clinical and radiographic differences between this lesion and a vestibular schwannoma helps to minimize perioperative morbidity. Surgical resection should be performed with special attention to preserving facial nerve function.

Melanocitoma meníngeo del ángulo pontocerebeloso, ¿Un tumor benigno? / Cerebellopontine angle meningeal melanocytoma: a benign tumor?

Se presenta un paciente con un raro melanocitoma meníngeo del ángulo pontocerebeloso que, tras su extirpación quirúrgica radical, evolucionó en el plazo de un año hacia una melanomatosis meníngea fulminante. Se realiza una revisión bibliográfica en busca de las claves para hacer una aproximación diagnóstica preoperatoria de este tipo de tumor y obtener información sobre su tratamiento y manejo postoperatorio (AU)

We report a case of a rare meningeal melanocytoma in the cerebellopontine angle. One year after tumor gross total removal, the patient suffered a sudden and devastating meningeal melanomatosis. The relevant literature is reviewed looking for the keys to establish preoperative diagnosis and to obtain information about its treatment and postsurgical management (AU)

Comentario al trabajo Melanocitoma meníngeo del ángulo pontocerebeloso, ¿Un tumor benigno?de González-Tortosa y cols / No disponible

No disponible

[Pediatric cochlear implants]. / Les implants cochléaires pédiatriques.

Indications for cochlear implants have been widened since 1995. Most implant candidates are children with severe congenital deafness. The cochlear implant must be inserted as early as possible for these children in order to optimize development of perception and language. A cochlear implant can also be discussed in certain particular cases for children with associated diseases, malformation of the inner ear, or severe deafness. The educational project must be realistic and take into account the future difficulties as well as an established set of criteria for successful language acquisition.

Malformaciones arteriovenosas del ángulo pontocerebeloso y del cerebelo / Cerebellopontine angle and cerebellum arteriovenous malformations

Las malformaciones arteriovenosas pueden ser descubiertas fortuitamente durante una evaluación de una patología no relacionada o pueden ser descubiertas en pacientes con signos clínicos. La presentación clínica es variable y los síntomas que incluye son el vértigo recurrente, acúfenos, inestabilidad e hipoacusia neurosensorial. Presentamos dos casos clínicos de malformaciones arteriovenosas del ángulo pontocerebeloso y del cerebelo: La primera en un paciente de 52 años de edad con hipoacusia neurosensorial izquierda y acúfenos y la segunda en una mujer de 34 años de edad con inestabilidad recurrente (AU)

Encephalocraniocutaneous lipomatosis with otolaryngologic manifestations: a rare neurocutaneous syndrome.

Encephalocraniocutaneous lipomatosis (ECCL) is a rare congenital disorder and was first described in 1970. The main clinical features of the syndrome include convulsions beginning in infancy, mental retardation, and unilateral cutaneous and ophthalmologic lesions with ipsilateral cerebral manifestations. A 14-year-old caucasian boy with ECCL associated with otolaryngologic manifestations is reported. To our knowledge, this is the first case of ECCL with otolaryngologic manifestation in the English literature.

Imaging in neurenteric cysts of the posterior cranial fossa.

Neurenteric cysts are cystic masses lined by a columnar epithelium of endodermal origin. They are rare in the central nervous system. We report two neurenteric cysts in the posterior cranial fossa and describe their neuroradiological features. The lesions were of low density on CT and more accurately delineated on MRI. They gave the same signal as cerebrospinal fluid on all sequences. There was no contrast enhancement.

Analysis of aberrant neuronal migrations in the hereditary cerebellar vermis defect (CVD) rat using bromodeoxyuridine immunohistochemistry.

The hereditary cerebellar vermis defect rat (CVD) is a new neurological mutant characterized by cerebellar vermis defect and a dysplastic cerebellum, especially in the cerebello-pontine junctions. In this study, the cytokinetics of neuronal migrations in the CVD were analyzed using 5-bromo-2'-deoxyuridine (BrdU) as a labeling marker. From embryonic day 21, the CVD cerebellum was small in size with retarded foliation, but no significant differences were detected in the migration pattern of the BrdU-labeled cells between the unaffected controls and the CVD during the prenatal period. On postnatal day 0 (P0), heterotopic Purkinje cells, demonstrable by calbindin immunohistochemistry, were seen in the dorsal pons of the CVD. From P4, BrdU-positive external granule cells (EGCs), which were labeled by BrdU injection on P2, began to penetrate the pons. From P5, the EGCs aggregated around the blood vessels, leading to a disturbance of the cerebellar lamination both in the cerebello-pontine junctions and in the cerebellar hemispheres. Thereafter, the BrdU-labeled cells in the perivascularly aggregated EGCs migrated radially, and formed internal granular layers around the vessels, indicating an aberrant perivascular migration of the EGCs. These findings suggest that the EGC dislocation was preceded by an aberrant settlement of the Purkinje cells, and that the perivascularly aggregated EGCs resulted in cerebellar dysplasia in the CVD.

Pontocerebellar hypoplasia with microcephaly and dyskinesia: report of two cases.

We present two clinically diagnosed cases of pontocerebellar hypoplasia with microcephaly and dyskinesia (pontocerebellar hypoplasia type 2) from two different Portuguese families. Both children presented neurological involvement from birth, progressive microcephaly, exuberant chorea and dystonia, myoclonic jerks, pontocerebellar hypoplasia, and progressive cerebral cortical atrophy. One child had consanguineous parents.

Computed tomographic analysis of hemifacial spasm: narrowing of the posterior fossa as a possible facilitating factor for neurovascular compression.

Hemifacial spasm can be caused by vascular compression of the facial nerve at the root exit zone from the brainstem. Several case reports suggest that narrowing of the cerebellopontine angle cistern caused by Paget's disease, abnormal elevation of the petrous bone caused by hyperplasia, or contralateral acoustic neurinoma may increase the chance of vascular compression of the facial nerve. Therefore, posterior fossa narrowness has been evaluated in 34 patients with hemifacial spasm by measuring the petrous angle and pons diameter index to elucidate whether narrowing of the posterior fossa can act as a facilitating factor for neurovascular compression. The petrous angle in the hemifacial spasm group was significantly smaller than that in the control group, which consisted of 33 patients with an unruptured supratentorial aneurysm, and the pons diameter index in the hemifacial spasm group was significantly greater than that in the control group. These results indicate that the cerebellopontine angle cistern of patients with hemifacial spasm is narrower resulting in more crowded cranial nerves and vascular structures compared with patients without hemifacial spasm. The narrowness of the cerebellopontine angle cistern may be a possible factor in facilitating neurovascular compression in hemifacial spasm.