Aneurisma trombosado de arteria comunicante anterior asociado a síntomas visuales / Thrombosed anterior communicating artery aneurysm associated with visual symptoms

Introducción: Los aneurismas de la arteria comunicante anterior (AComA) se presentan frecuentemente como causa de hemorragia subaracnoidea espontánea (HSAE), en casos raros se asocian a síntomas visuales por compresión mecánica o ruptura y su tratamiento quirúrgico a menudo representa un desafío. Descripción del caso: Se presenta el caso clínico de una paciente adulta con disminución de la agudeza visual del ojo derecho a predominio temporal, y hallazgos en RMN cerebral y angiografía compatibles con un aneurisma grande de AcomA, asociado a trombosis parcial; se realizó clipaje y trombectomía del aneurisma, la panangiografia de control evidenció exclusión completa de la lesión con posterior resolución del déficit visual. Discusión: El déficit visual por un aneurisma de la AcoA se puede generar por varios mecanismos, uno de ellos es la ruptura del aneurisma hacia el nervio óptico, con la subsecuente formación de un hematoma, adherencias y fibrosis; el otro mecanismo es la compresión mecánica de un aneurisma gigante no roto. El manejo quirúrgico a menudo implica técnicas complejas microquirúrgicas para intentar resolver el efecto de masa y excluir el aneurisma. La terapia endovascular es otra alternativa de tratamiento, pero tiene desventajas respecto a la cirugía. Conclusión: Los aneurismas de la AComA en raros casos se pueden asociar a síntomas visuales, debido a que por lo general se romepen cuando son pequeños, y no alcanzan a tener el tamaño suficiente para generar compresión de la vía óptica. Las técnicas microquirúrgicas ofrecen un método efectivo para disminuir el efecto de masa y mejorar los síntomas visuales

Introduction: Aneurysms of the anterior communicating artery (AComA) frequently present as a cause of spontaneous subarachnoid hemorrhage (HSAE), in rare cases they are associated with visual symptoms due to mechanical compression or rupture and their surgical treatment often represents a challenge. Description of the case: We present the clinical case of an adult patient with a decrease in visual acuity due to the right eye with a temporal predominance and findings on brain MRI and angiography compatible with a large AcomA aneurysm associated with partial thrombosis; clipping and thrombectomy of the aneurysm were performed, the control panangiography showed complete exclusion of the lesion. With subsequent resolution of the visual deficit. Discussion: The visual deficit due to an AcoA aneurysm can be generated by several mechanisms, one of them is the rupture of the aneurysm towards the optic nerve, with the subsequent formation of a hematoma, adhesions and fibrosis; The other mechanism is mechanical compression of a giant, unruptured aneurysm. Surgical management often involves complex microsurgical techniques to try to resolve the mass effect and exclude the aneurysm. Endovascular therapy is another treatment alternative, but it has disadvantages compared to surgery. Conclusion: AComA aneurysms in rare cases can be associated with visual symptoms, because they generally rupture when they are small, and are not large enough to generate compression of the optic pathway. Microsurgical techniques offer an effective method to alleviate the mass effect and improve visual symptoms

Neurofibromatosis tipos 1 y 2 / Neurofibromatosis type 1 and 2

La neurofibromatosis (NF) comprende un grupo de enfermedades genéticas de herencia autosómica dominante, que se clasifican de la siguiente manera: neurofibromatosis tipo 1 (NF1), neurofibromatosis tipo 2 (NF2) y schwannomatosis (también conocida como neurofibromatosis tipo 3). Esta última es una enfermedad muy infrecuente, con una prevalencia aproximada de 1/126 000 personas, por lo que solo profundizaremos las dos primeras. La NF1, también conocida como la enfermedad de Von Recklinghausen, es la más frecuente de las tres y afecta principalmente la piel y el sistema nervioso periférico. Se caracteriza por la presencia de máculas "café con leche", pecas axilares o inguinales, nódulos de Lisch (hamartomas en el iris) y neurofibromas (tumores de la vaina de nervios periféricos). Otras manifestaciones menos frecuentes, aunque de mayor gravedad, incluyen gliomas del nervio óptico, meningiomas, neurofibromas malignos, escoliosis y displasia de la tibia. Su diagnóstico se suele realizar al nacimiento o durante los primeros años de vida, y se estima que un 50% de quienes la padecen presenta dificultades cognitivas. No hay datos concluyentes sobre la mortalidad en los pacientes con NF1, aunque se sabe que la expectativa de vida es menor que en la población general. La NF2 tiene una prevalencia considerablemente menor que la NF1 y su inicio es más tardío, afectando principalmente a adultos jóvenes. La presentación clínica típica se caracteriza por acúfenos, hipoacusia y ataxia en contexto de la presencia de schwannomas vestibulares bilaterales. Otros hallazgos menos frecuentes incluyen schwannomas de nervios periféricos, meningiomas, ependimomas o astrocitomas. La esperanza de vida es de unos 36 años, con una supervivencia media desde el momento del diagnóstico de 15 años. (AU)

Neurofibromatosis (NF) includes a group of genetic diseases with an autosomal-dominant inheritance pattern, and they are classified as follows: Neurofibromatosis type 1 (NF1), neurofibromatosis type 2 (NF2) and Schwannomatosis (also known as neurofibromatosis type 3). This last one is a very rare disease, with an approximate prevalence of 1/126000, so we will only deepen in the first two. NF1, also known as von Recklinghausen disease, is the most frequent, and mainly affects the skin and peripheral nervous system. Its typical manifestations are the presence of café-au-lait macules, axillary or inguinal freckles, Lisch nodules (hamartomas in the iris) and neurofibromas (peripheral nerve sheath tumors). Less frequent manifestations, although more serious, include optic nerve gliomas, meningiomas, malignant neurofibromas, scoliosis and tibial dysplasia. The diagnosis is usually made at birth or during the first years of life, and approximately 50% of patients present cognitive difficulties. There is no conclusive data on mortality in patients with NF1, although it is known that life expectancy is lower than in general population. NF2 has a considerably lower prevalence than NF1, and its onset is later in life, mainly affecting young adults. Its typical clinical presentation is characterized by tinnitus, hearing loss and ataxia in the context in the presence of bilateral vestibular schwannomas. Less frequent findings include peripheral nerve schwannomas, meningiomas, ependymomas or astrocytomas. Life expectancy is about 36 years old, with a median survival from the moment of diagnosis of 15 years. (AU)

Correlation of MRI Findings in Optic Pathway Glioma with the Presence of Neurofibromatosis

Background: Optic nerve glioma (also known as optic pathway glioma) is the  most common primary neoplasm of the optic nerve. The tumor can arise anywhere along the optic pathway from behind the globe to the occipital cortex. Optic pathway gliomas (OPGs) are associated with high rate of visual morbidity and mortality. Studies have shown no specific clinical histologic or neuro imaging features to differentiate aggressive from non-aggressive OPGs. Purpose: The biological behaviour of optic pathway glioma is unpredictable and it is not clear if specific anatomical patterns may be of use in prognosis of the OPGs. The prognosis is reportedly better in OPGs associated with neurofibromatosis (NF). The purpose of the study was to compare the MRI findings between patients with NF, with those without NF and to determine prognostic imaging signs if any. Material and Methods - MRI studies of 41 patients with OPG (21 with NF and 20 without NF)  were reviewed at presentation and at follow up. Statistical bivariate analysis was used to compare the size and extension of tumor between patients with and those without NF.  Results: Orbital component of the optic nerve was most commonly involved in patients with NF (65%) with optic chiasma being the most common site of involvement (90%) in the non NF group. Extension beyond the optic pathway at diagnosis was more frequent in the non-NF group. In patients with NF, the morphological appearance of the optic nerve was preserved with the tumor being of limited size as compared to the patients in the non-NF group. Statistically significant correlation between MRI features and growth pattern of glioma was absent. Conclusion: As per our study we found that more than half the NF patient’s tumor size  remained stable in contrast to less than 5% of the non-NF group. Although no statistical correlation was found between MRI imaging and the biological behaviour of the tumor, we can infer that NF OPG is a separate entity from non-NF OPG with different prognostic features requiring a customised approach as per the type.

Optochiasmatic Cavernous Angioma with Rapid Progression after Biopsy Despite Radiation Therapy

We present a rare case of optochiasmatic cavernous angioma (CA) that progressed despite radiation therapy. A 31-year-old female patient presented with sudden loss of left visual acuity and right homonymous hemianopsia. Magnetic resonance imaging (MRI) revealed a suprasellar mass and findings compatible with a craniopharyngioma or an optic glioma with bleeding. An open biopsy was conducted using the transcranial approach, and histological examination revealed gliosis. During the one-year follow-up period, imaging suggested intratumoral bleeding and the mass continued to grow. We recommended re-operation, but the patient refused due to fear of surgery. Consequently, the patient received fractionated radiation therapy (3,000 cGy) to the parasellar area. Despite the radiotherapy, the mass continued to grow for the following 6 years. The final MRI before definitive treatment revealed a multilobulated, multistage hematoma with calcification in the parasellar area, extending into the third ventricle and midbrain. The patient ultimately underwent reoperation due to the growth of the tumor. The mass was completely removed with transcranial surgery, and the pathologic findings indicated a cavernous angioma (CA) without evidence of glioma. As shown in our case, patients may suffer intratumoral hemorrhage after biopsy and radiotherapy. This case places the value of biopsy and radiotherapy for a remnant lesion into question. It also shows that reaching the correct diagnosis is critical, and complete surgical removal is the treatment of choice.

Anterior Communicating Artery Aneurysm Related to Visual Symptoms

OBJECTIVE: Intracranial aneurysms are sometimes presented with visual symptoms by their rupture or direct compression of the optic nerve. It is because their prevalent sites are anatomically located close to the optic pathway. Anterior communicating artery is especially located in close proximity to optic nerve. Aneurysm arising in this area can produce visual symptoms according to their direction while the size is small. Clinical importance of visual symptoms presented by aneurysmal optic nerve compression is stressed in this study. METHODS: Retrospective analysis of ruptured anterior communicating artery aneurysms compressing optic apparatus were carried out. Total 33 cases were enrolled in this study. Optic nerve compression of the aneurysms was confirmed by the surgical fields. RESULTS: In 33 cases among 351 cases of ruptured anterior communicating artery aneurysms treated surgically, from 1991 to 2000, the dome of aneurysm was compressed in optic pathway. In some cases, aneurysm impacted into the optic nerve that deep hollowness was found when the aneurysm sac was removed during operation. Among 33 cases, 10 cases presented with preoperative visual symptoms, such as visual dimness (5), unilateral visual field defect (2) or unilateral visual loss (3), 20 cases had no visual symptoms. Visual symptoms could not be checked in 3 cases due to the poor mental state. In 6 cases among 20 cases having no visual symptoms, optic nerve was deeply compressed by the dome of aneurysm which was seen in the surgical field. Of 10 patients who had visual symptoms, 8 showed improvement in visual symptoms within 6 months after clipping of aneurysms. In 2 cases, the visual symptoms did not recover. CONCLUSION: Anterior communicating artery aneurysm can cause visual symptoms by compressing the optic nerve or direct rupture to the optic nerve with focal hematoma formation. We emphasize that cerebral vascular study is highly recommended to detect intracranial aneurysm before its rupture in the case of normal CT findings with visual symptoms and frequent headache.

The Role of Adjunctive Therapy of Optic Pathway Glioma in Children

OBJECTIVE: This study is performed in order to compare the outcomes of surgical management and to define the role of adjunctive therapy in the management of optic pathway glioma in children. METHODS: Sixteen children with optic pathway glioma had been managed in various treatment methods during the last 8 years. The patients aged from 5 months to 14 years. The patients presented with progressive visual loss, increased ICP symptoms, endocrine dysfunction, seizure, and motor weakness. Optic pathway glioma associated with neurofibromatosis was excluded. Tumor involved chiasmatico-hypothalamus(12 patients), optic chiasm(3), and optic nerve(1). The extent of surgical resection were radical(3 patients), subtotal(12), and partial(1). RESULTS: Three patients treated with radical resection showed no evidence of tumor recurrence. Among 12 patients treated with subtotal resection and without adjunctive therapy, 6 patients(50%) developed recurrence in the postoperative period of average 20.5 months. Those patients with recurrence were managed by reoperation(3 patients), irradiation therapy(2), and chemotherapy(1). However three patients with residual tumors after subtotal(2), or partial(1) resection were treated with adjunctive chemotherapy in the postoperative period showed no evidence of recurrence. CONCLUSION: Although radical resection of optic pathway glioma might offer long-term control of tumor, adjunctive chemotherapy could be effective to prevent tumor recurrence in children with subtotally or partially resected optic pathway glioma. More experience is necessary to determine the optimal method of treatment of optic pathway gliomas in children.

Management of Chiasmatic-Hypothalamic Gliomas in Children

OBJECTIVE: Management strategies for pediatric chiasmatic-hypothalamic gliomas(CHG) include surgery, irradiation, chemotherapy and a combination of these modalities. This study was performed in order to compare the efficacy of various methods of treatment and to describe its optimal management. MATERIAL AND METHOD: We have reviewed the results of management of 6 children with a diagnosis of CHG, who were observed closely during the last 8 years. The patients were aged 7 months to 15 years. Our patients presented with diencephalic syndrome, endocrine dysfunction, and progressive visual loss. None of these had evidence of neurofibromatosis-1. Treatment consisted of surgery alone(2), surgry and irradiation(2), surgery, irradiation and chemotherapy(1), and surgery and chemotherapy(1). RESULTS: Four children had large exophytic suprasellar tumors and two showed diffuse midline lesions. Obstructive hydrocephalus was present in all patients. Pathologic examination revealed anaplastic astrocytoma in 1 and low-grade astrocytoma in 5. Two patients, recently treated with radiation therapy following radical subtotal resection, showed significant tumor reductions and good clinical status. Four patients had partial tumor resection. Of these patients, two developed disease stabilization during follow-up period of 7 and 8 years, respectively. Life-threatening complications were noted in remaining two patients. CONCLUSION: CHG may follow an unpredicatable course and show a various reponse to each treatment modality. Further studies are indicated to define the optimal method of treatment of CHG in childhood.

Gamma Knife Radiosurgery for Craniopharyngioma

OBJECTIVE: The purpose of this study are to evaluate the effectiveness of Gamma Knife radiosurgery(GKS) as a treatment of craniopharyngioma and to investigate the proper dose planning technique in GKS for craniopharyngioma. METHOD: Between May 1992 and March 1999, seven Gamma Knife radiosurgical procedures were done for residual tumor mass of 6 patients with craniopharyngioma after microsurgical resection. Conventional radiation therapy was not performed. In this study, their clinical, radiological and radiosurgical data were analyzed and the radiation dosage to the optic pathway, hypothalamus, pituitary stalk, and cavernous sinus were calculated and correlation with clinical outcome was evaluated. The mean follow-up period was 33.5 months(12.3-55.2 months). RESULT: The mean tumor volume was 4.4cc(0.4-18.0cc) and the maximum radiation dose ranged from 14 to 32 Gy(mean 20.9Gy). The radiation was given with isodose curve, 50-90% and the marginal dose varied within 8-22.4Gy(mean 12.7Gy). The mean number of isocenter was 4.3(1-12). The tumor was well controlled in all cases. In 5 of 7 cases, the size of tumor decreased to 10-50% of pre-GKS volume and remaining two showed no volume change. The mean dose to optic pathway was 5.7Gy(5.1-11.2Gy) and there were no complications. CONCLUSION: GKS seems to be effective for control of craniopharyngioma as an adjuvant treatment after microsurgical resection and even suboptimal dose for tumor margin is considered to be enough for tumor control. It is safe with careful dose planning to protect surrounding important structures, especially optic pathway. We believe conventional radiation therapy should be avoided because it has limitation for dose planning of additional treatments such as radiosurgery or intracystic instillation of radioisotope in case of recurrence.

TRANSECTION OF THE OPTIC NERVE INDUCES EXPRESSION OF THE SMALL HEAT SHOCK PROTEIN HSP27 IN THE OPTIC PATHWAY OF GOLDEN HAMSTER / 解剖学报

Objective To observe the expression of the small heat shock protein (HSP27) in the optic chiasma (OC), optic tract (OT), dorsal lateral geniculate body(LG) and superior colliculus (SC) of the adult golden hamster after intraorbital transection of the left optic nerve (ON). Methods The experimental animals were left to survive for l, 2, 3, 4, 5, 6, 8 weeks following ON transection. The animals were perfused with formol-saline and brains were excised, sectioned and stained with the immunohistochemistry. The sections were observed under the light microscope, the optical density (A) was measured and the data were analysed statistically. Results Immunohistochemical results indicated that the HSP27-expressions were not different between the right and left side of the OC, OT, LG and SC in normal or sham-operation controls. However, following transection of the left ON, HSP27 immunohistochemical stainings in the right site of OC, OT,LG and SC were increased, comparing with the left side. The maximum difference of HSP27 immunostaining between the right and left side appeared in the lst week following left ON axotomy. The sharply decrease of the A difference occurred at the 2nd week after axotomy with insignificant changes in the subsequent several weeks. And the significant A difference was observed in most time except 6th week. Most of HSP27-positive cells had morphological appearances similar to astrocytes with smaller cell body and numerous processes. Conclusion After the transection of monolateral ON, HSP27 expressions in the contralateral optic pathway of brain increased and persisted up to 8 weeks. This result suggested that the increase of HSP27 expression had something to do with the injury of the optic pathway, but the mechanism and biological significance of the increase in HSP27 expression level required to be studied further.;