RESUMEN

Subarachnoid haemorrhage (SAH) is a quite rare but serious central nervous system complication of eosinophilic granulomatosis with polyangiitis (EGPA). We report a case of myeloperoxidase antineutrophil cytoplasmic antibody-positive EGPA in which SAH developed during glucocorticoid induction pulse therapy for skin purpura, peripheral neuropathy, and rapidly progressive glomerulonephritis. In addition to high-dose glucocorticoid and intravenous cyclophosphamide, we administered mepolizumab, a humanised anti-interleukin-5 monoclonal antibody, and this resulted in remission of the SAH. Although the pathogenesis of SAH in EGPA is not fully understood, both necrotising vasculitis and eosinophilic inflammation are thought to be involved. In addition to prompt intensive immunosuppressive therapy, mepolizumab should be considered for SAH associated with EGPA.

Asunto(s)

Anticuerpos Anticitoplasma de Neutrófilos , Anticuerpos Monoclonales Humanizados , Ciclofosfamida , Glucocorticoides , Inmunosupresores , Hemorragia Subaracnoidea , Humanos , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Hemorragia Subaracnoidea/etiología , Hemorragia Subaracnoidea/diagnóstico , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Glucocorticoides/administración & dosificación , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Anticitoplasma de Neutrófilos/inmunología , Resultado del Tratamiento , Inmunosupresores/uso terapéutico , Inmunosupresores/administración & dosificación , Síndrome de Churg-Strauss/diagnóstico , Síndrome de Churg-Strauss/complicaciones , Síndrome de Churg-Strauss/tratamiento farmacológico , Peroxidasa/inmunología , Granulomatosis con Poliangitis/tratamiento farmacológico , Granulomatosis con Poliangitis/diagnóstico , Granulomatosis con Poliangitis/complicaciones , Masculino , Quimioterapia Combinada , Persona de Mediana Edad , Femenino

RESUMEN

We report for the first time a case of choroid plexus papilloma (CPP) of the fourth ventricle associated with adrenal pheochromocytoma. A large tumor was found in the fourth ventricle of a 24-year-old man who presented with symptoms of increased intracranial pressure due to obstructive hydrocephalus. A systemic search revealed that the patient also had an asymptomatic left adrenal tumor. Both tumors were resected. The pathological diagnosis of the brain tumor was CPP and that of the adrenal tumor was pheochromocytoma, both of which showed no pathological signs of malignancy. Genetic testing for von Hippel-Lindau disease was negative. There have been no reports of cases of CPP associated with pheochromocytoma. In this report, we discuss the relationship between both tumors.

RESUMEN

BACKGROUND: Understanding of cortico-cortical activity in eloquent areas intraoperatively is crucial for neurosurgical procedures. Here, we used intraoperative near-infrared spectroscopy (iNIRS) during direct cortical stimulation as a robust tool to better understand the cortico-cortical connectivity in language systems. METHODS: We applied iNIRS to 3 patients who underwent epilepsy surgery due to lesions (cavernous angioma, epidermoid cyst, and low-grade glioma) located in language areas. Using iNIRS, we measured the blood concentration changes of oxyhemoglobin (HbO2) and deoxyhemoglobin (HbR) in the lateral temporal cortex during direct cortical stimulation (50Hz) at the inferior frontal area where Broca's area was probabilistically located. RESULTS: In all patients, 50Hz stimulation elicited hemodynamic changes in the superior temporal gyrus (STG). During 0.8-4.8s after stimulation, HbO2 increased and HbR decreased in the posterior part of the STG (Wernicke's area). Similar responses were observed in the anterior part of the STG 1.3-8.0s after stimulation. Finally, these changes were disappeared in the middle temporal gyrus. CONCLUSIONS: Our results suggest that cortical stimulation of Broca's area elicits hemodynamic responses in Wernicke's area via cortico-cortical connectivity. We demonstrated cortico-cortical evoked responses in language systems using iNIRS during direct cortical stimulation. Our iNIRS data will provide useful information about cortico-cortical networks underlying human brain functions intraoperatively and will contribute to neurosurgical treatment in eloquent areas.

Asunto(s)

Área de Broca/fisiología , Lenguaje , Espectroscopía Infrarroja Corta/métodos , Área de Wernicke/fisiología , Adolescente , Adulto , Niño , Estimulación Eléctrica , Epilepsia/cirugía , Femenino , Hemodinámica , Humanos , Masculino , Vías Nerviosas/fisiología

RESUMEN

The authors report the case of a mobile spinal enterogenous cyst in a 2-year-old boy, who was admitted to the hospital several times for intermittent paraplegia. Magnetic resonance imaging and CT revealed an isolated cyst in the lumbar spinal canal. The symptoms were caused by transient myelopathy of the conus medullaris and radiculopathy of the cauda equina due to the changing size and location of the cyst. The cyst was surgically extirpated, after which the symptoms resolved. The histopathological diagnosis was enterogenous cyst. The clinical history of intraspinal enterogenous cyst is usually progressive. Mobility and changes in size are rare pathophysiological findings. The authors speculate that the cyst wall did not adhere to the surrounding structures and had ruptured and quickly reformed. Enterogenous cyst should be considered in the differential diagnosis of spinal intradural cysts in children with radiculomyelopathy.

Asunto(s)

Cauda Equina , Quistes , Vértebras Lumbares/anomalías , Paraplejía/etiología , Enfermedades del Sistema Nervioso Periférico/cirugía , Canal Medular/anomalías , Enfermedades de la Médula Espinal/cirugía , Cauda Equina/diagnóstico por imagen , Preescolar , Quistes/complicaciones , Quistes/diagnóstico por imagen , Quistes/cirugía , Diagnóstico Diferencial , Humanos , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Masculino , Paraplejía/diagnóstico por imagen , Paraplejía/cirugía , Enfermedades del Sistema Nervioso Periférico/complicaciones , Enfermedades del Sistema Nervioso Periférico/diagnóstico por imagen , Canal Medular/diagnóstico por imagen , Canal Medular/cirugía , Enfermedades de la Médula Espinal/complicaciones , Enfermedades de la Médula Espinal/diagnóstico por imagen

RESUMEN

BACKGROUND: Although the superficial middle cerebral vein (SMCV) usually connects with the cavernous sinus, there are several anatomical variations. We determined whether differences in SMCV drainages patterns affected the perioperative management of petroclival meningioma. METHODS: The subjects included 17 patients (4 men; 13 women) who underwent resection of a petroclival meningioma. SMCV drainage patterns were classified into four groups according to angiographic findings: (1) The SMCV connected with the cavernous sinus (Group A); (2) The SMCV was either absent or connected directly with the superior sagittal or transverse sinus through the cortical veins (Group B); (3) The SMCV turned downward and connected with the pterygoid plexus through the sphenobasal vein (SpBV, Group C); and (4) The SMCV ran across the bottom of the middle fossa and connected with transverse sinus via the sphenopetrosal sinus (SpPS, Group D). RESULTS: In all 9 patients in Group A, the SMCV drainage pattern did not affect any aspect of perioperative management. In contrast, SMCV drainage patterns in 3 of 4 patients in Group B and both patients in Groups C and D had an effect on perioperative management, indicating a significant impact of variations in SMCV drainage patterns (P < 0.005). In 2 patients in Group C and 1 in Group D, the operating corridor provided by a transpetrosal approach was small in order to preserve the SpBV or SpPS. In the other patient in Group D, an anterior transpetrosal approach was not selected preoperatively because the SpPS would likely be injured during surgery. CONCLUSIONS: In cases, where the SMCV directly connects with superior sagittal or transverse sinus, SpBV or SpPS, surgeons have to meticulously select a safe and effective approach and take measures to preserve the SpBV or SpPS during surgery.

RESUMEN

BACKGROUND: The aim of this work is to determine if free-running electromyography (frEMG) can detect activity before and after microvascular decompression (MVD) treatment for hemifacial spasm (HFS), and to evaluate correlations of frEMG findings with abnormal muscle responses (AMRs) or facial motor-evoked potentials (FMEPs). METHODS: To elicit nerve responses while carrying out frEMG recording before and after MVD, saline, a lactic solution, or artificial cerebrospinal fluid was injected onto the root exit zone of the facial nerve. RESULTS: Significantly higher frEMG activity was observed following saline injection than for the other solutions (p < 0.01). For frEMG activity ratios of ≥ 50 %, there was a trend towards a greater likelihood of persistent AMRs. When frEMG activity decreased after MVD in the mentalis muscles, FMEP amplitude ratios were significantly smaller than when it did not (65 vs. 94 %, p < 0.05). CONCLUSIONS: Changes in intraoperative frEMG, AMRs, and FMEPs likely reflect a component of the normalization of hyper-excitability of the facial nerve by MVD for HFS.

Asunto(s)

Electromiografía/métodos , Espasmo Hemifacial/cirugía , Cirugía para Descompresión Microvascular/métodos , Adulto , Anciano , Potenciales Evocados Motores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos

RESUMEN

OBJECTIVE: Monitoring pharyngeal motor evoked potential (PhMEP) with a modified endotracheal tube is useful for predicting postoperative swallowing dysfunction. However, the relationship between intraoperative PhMEP findings and recovery from postoperative swallowing dysfunction has not been clarified. The aim of this study was to determine whether PhMEP monitoring predicts swallowing dysfunction not only immediately after surgery but also in the postoperative recovery period. METHODS: We analyzed PhMEPs in 36 patients during treatment for skull base tumors. Recovery from postoperative swallowing dysfunction was evaluated when oral intake was started postsurgery and drip or tube feeding was discontinued. The correlation between the final to baseline PhMEP ratio and postoperative recovery times from swallowing dysfunction was examined. RESULTS: The PhMEP ratio significantly correlated with postoperative swallowing function immediately after surgery (P < 0.001). The period before starting oral intake in patients with a PhMEP ratio >50% (mean ± standard deviation [SD], 3.8 ± 4.3 days) was shorter than those with a PhMEP ratio ≤50% (mean ± SD, 14.7 ± 11.8 days; P < 0.01). Drip or tube feeding was removed from patients with a PhMEP ratio >50% significantly earlier (mean ± SD, 13.7 ± 19.2 days) than those with a PhMEP ratio ≤50% (mean ± SD, 38.3 ± 27.3 days; P < 0.05). Both univariate and multivariate analysis showed that only the PhMEP ratio was predictive of early recovery from swallowing dysfunction. CONCLUSIONS: PhMEP monitoring allowed us to predict not only immediate swallowing dysfunction but also recovery from the dysfunction in the postsurgery period.

Asunto(s)

Trastornos de Deglución/diagnóstico , Trastornos de Deglución/fisiopatología , Potenciales Evocados Motores/fisiología , Monitoreo Intraoperatorio , Músculos Faríngeos/inervación , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/fisiopatología , Neoplasias de la Base del Cráneo/cirugía , Adulto , Anciano , Femenino , Estudios de Seguimiento , Nervio Glosofaríngeo/fisiopatología , Humanos , Intubación Intratraqueal , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Base del Cráneo/cirugía , Estadística como Asunto , Estimulación Transcraneal de Corriente Directa , Nervio Vago/fisiopatología

RESUMEN

BACKGROUND: The supplementary motor area (SMA) makes multiple reciprocal connections to many areas of the cerebral cortices, such as the primary motor cortex (PMC), anterior cingulate cortex, and various regions in the parietal somatosensory cortex. In patients with SMA seizures, epileptic discharges from the SMA rapidly propagate to the PMC. We sought to determine whether near-infrared spectroscopy (NIRS) is able to intraoperatively display hemodynamic changes in epileptic network activities between the SMA and the PMC. CASE DESCRIPTIONS: In a 60-year-old male with SMA seizures, we intraoperatively delivered a 500 Hz, 5-train stimulation to the medial cortical surface and measured the resulting hemodynamic changes in the PMC by calculating the oxyhemoglobin (HbO2) and deoxyhemoglobin (HbR) concentration changes during stimulation. No hemodynamic changes in the lateral cortex were observed during stimulation of the medial surface corresponding to the foot motor areas. In contrast, both HbO2 and HbR increased in the lateral cortex corresponding to the hand motor areas when the seizure onset zone was stimulated. In the premotor cortex and the lateral cortex corresponding to the trunk motor areas, hemodynamic changes showed a pattern of increased HbO2 with decreased HbR. CONCLUSIONS: This is the first reported study using intraoperative NIRS to characterize the epileptic network activities between the SMA and PMC. Our intraoperative NIRS procedure may thus be useful in monitoring the activities of cortico-cortical neural pathways such as the language system.

RESUMEN

OBJECTIVE: To determine whether various clinical factors are related to long-term outcomes of patients with sporadic cerebellar hemangioblastomas. METHODS: Subjects included 36 patients (19 men and 17 women) who underwent resection of sporadic hemangioblastoma in the cerebellum. Age at surgery ranged from 17-79 years (mean, 49.7 years). The tumor size, which was defined as the largest diameter of the lesion including the extratumoral cyst, ranged from 10-67 mm (mean, 36.4 mm). Obstructive hydrocephalus secondary to mass effect on the fourth ventricle was present in 21 (58.3%) patients preoperatively. RESULTS: Total tumor removal was achieved in 31 of 36 patients (86%). In 4 (11%) patients with solid tumors, postoperative hematoma occurred in the removal cavity, and hematoma removal was required immediately after surgery. We followed 30 patients for >12 months after the initial surgery (mean, 72.9 months; range, 12-274 months). Recurrence of hemangioblastoma developed in 4 of 30 patients (13%) at 6 months, 17 months, 6 years, and 22 years after surgery. At the final follow-up examination, 9 (30%) of 30 patients showed some residual neurologic symptoms (poor group), whereas the remaining 21 patients showed no deficits (good group). Using univariate analysis, both age at surgery and tumor characteristics (cystic or solid) were significantly related to long-term patient outcomes (P < 0.05). However, in a multiple logistic regression analysis, only tumor characteristics were correlated with outcomes (P = 0.017). At the final follow-up examination, patients with solid tumors more frequently showed poor outcomes than patients with cystic tumors. CONCLUSIONS: The solid configuration observed on preoperative images of sporadic cerebellar hemangioblastomas is one of the most important clinical factors related to both immediate and long-term outcomes after surgery.

Asunto(s)

Neoplasias Cerebelosas/patología , Neoplasias Cerebelosas/cirugía , Hemangioblastoma/patología , Hemangioblastoma/cirugía , Imagen por Resonancia Magnética/métodos , Procedimientos Neuroquirúrgicos/métodos , Adolescente , Adulto , Anciano , Angiografía de Substracción Digital , Ataxia Cerebelosa/etiología , Neoplasias Cerebelosas/terapia , Angiografía Cerebral , Terapia Combinada , Trastornos de Deglución/etiología , Embolización Terapéutica/métodos , Femenino , Estudios de Seguimiento , Hemangioblastoma/terapia , Humanos , Hidrocefalia/patología , Hidrocefalia/cirugía , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Procedimientos Neuroquirúrgicos/efectos adversos , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Adulto Joven

RESUMEN

BACKGROUND: Swallowing disturbance is among the most burdensome complications suffered by patients with glossopharyngeal and vagus nerve involvement in lesions adjacent the jugular foramen. For monitoring these nerves, we have developed new devices that comprised four contacts adhering to the surface of the cuff of an endotracheal tube, with attachment the posterior pharyngeal wall. To determine whether these devices are useful for monitoring the glossopharyngeal and vagus nerves and predicting postoperative swallowing dysfunction in patients undergoing removal of skull base tumors involving these nerves. METHODS: We studied 10 patients. Compound muscle action potentials (CMAPs) were recorded from the posterior pharyngeal wall by stimulating the glossopharyngeal or vagus nerve in order to identify the nerve course, especially in patients showing severe nerve distortion due to the tumor. Pharyngeal motor evoked potential (PhMEP) elicited by transcranial electrical stimulation were recorded in all patients. The correlation between the final to baseline PhMEP ratio and postoperative swallowing function was examined. RESULTS: Responses were obtained in six of the seven patients in whom CMAP monitoring was performed. Deterioration of swallowing function postoperatively was demonstrated in six of seven (86%) patients with intraoperative PhMEP ratios <50%. None of the three patients with intraoperative PhMEP ratios >50% showed deterioration of swallowing function after surgery, although the one patient already had severe swallowing dysfunction requiring preoperative tracheostomy. CONCLUSIONS: Our novel devices were useful for monitoring the glossopharyngeal and vagus nerves in patients undergoing removal of skull base tumors involving these nerves.

RESUMEN

OBJECT: The authors adopted the infrafloccular approach for microvascular decompression (MVD) surgery to treat hemifacial spasm (HFS). The inferior portion of the flocculus is retracted to observe the root exit zone of cranial nerve (CN) VII between CN IX and the flocculus. During the procedure, the rhomboid lip, a sheetlike layer of neural tissue forming the lateral recess of the fourth ventricle, is sometimes encountered. The existence of the rhomboid lip in cases of HFS was reviewed to determine the importance of the structure during MVD surgery. METHODS: Preoperative imaging and intraoperative observations in 34 consecutive cases of HFS treated in the period from October 2008 through September 2011 were used to assess the frequency of encountering the rhomboid lip. RESULTS: The rhomboid lip was observed during MVD surgery in 9 (26.5%) of the 34 cases but had been demonstrated on preoperative MR images in only 3 cases (8.8%). On T2-weighted images, it appeared as a high-intensity nonstructural area on the ventral side of the flocculus and continued into the fourth ventricle via the foramen of Luschka. CONCLUSIONS: A large rhomboid lip presents an impediment to MVD surgery in a significant minority of patients with HFS. It is seldom observed on preoperative MR images. Proper dissection of the rhomboid lip away from the arachnoid membrane and/or the lower CNs during MVD surgery provides good visualization of the root exit zone of CN VII and reduces injury of CNs IX and X, avoiding postoperative deficits like dysphagia.

Asunto(s)

Nervio Facial/cirugía , Cuarto Ventrículo/cirugía , Espasmo Hemifacial/cirugía , Cirugía para Descompresión Microvascular/métodos , Femenino , Humanos , Persona de Mediana Edad , Monitoreo Intraoperatorio , Resultado del Tratamiento

RESUMEN

OBJECT: In this paper, the authors' goal was to report their novel presurgical simulation method applying interactive virtual simulation (IVS) using 3D computer graphics (CG) data and microscopic observation of color-printed plaster models based on these CG data in surgery for skull base and deep tumors. METHODS: For 25 operations in 23 patients with skull base or deep intracranial tumors (meningiomas, schwannomas, epidermoid tumors, chordomas, and others), the authors carried out presurgical simulation based on 3D CG data created by image analysis for radiological data. Interactive virtual simulation was performed by modifying the 3D CG data to imitate various surgical procedures, such as bone drilling, brain retraction, and tumor removal, with manipulation of a haptic device. The authors also produced color-printed plaster models of modified 3D CG data by a selective laser sintering method and observed them under the operative microscope. RESULTS: In all patients, IVS provided detailed and realistic surgical perspectives of sufficient quality, thereby allowing surgeons to determine an appropriate and feasible surgical approach. Surgeons agreed that in 44% of the 25 operations IVS showed high utility (as indicated by a rating of "prominent") in comprehending 3D microsurgical anatomies for which reconstruction using only 2D images was complicated. Microscopic observation of color-printed plaster models in 12 patients provided further utility in confirming realistic surgical anatomies. CONCLUSIONS: The authors' presurgical simulation method applying advanced 3D imaging and modeling techniques provided a realistic environment for practicing microsurgical procedures virtually and enabled the authors to ascertain complex microsurgical anatomy, to determine the optimal surgical strategies, and also to efficiently educate neurosurgical trainees, especially during surgery for skull base and deep tumors.

Asunto(s)

Simulación por Computador , Imagenología Tridimensional/métodos , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Cuidados Preoperatorios/métodos , Neoplasias de la Base del Cráneo/cirugía , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/cirugía , Cordoma/diagnóstico por imagen , Cordoma/patología , Cordoma/cirugía , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/patología , Meningioma/diagnóstico por imagen , Meningioma/patología , Persona de Mediana Edad , Modelos Anatómicos , Neurilemoma/diagnóstico por imagen , Neurilemoma/patología , Neurilemoma/cirugía , Neoplasias de la Base del Cráneo/diagnóstico por imagen , Neoplasias de la Base del Cráneo/patología , Programas Informáticos , Tomografía Computarizada por Rayos X , Interfaz Usuario-Computador , Adulto Joven

RESUMEN

OBJECTIVE: To determine whether motor evoked potentials(MEPs)provide reliable monitoring of the motor system during resection of gliomas in or adjacent to the motor cortex or pyramidal tract. MATERIALS AND METHODS: MEP recording was performed during 64 operations in 55 patients harboring gliomas. Intraoperative MEP findings were classified into 3 groups:Group A was defined as having no significant MEP changes, Group B as having reversible MEP changes(?50% amplitude decrease or loss), and Group C as having irreversible changes. Postoperative motor function was evaluated according to the presence/absence of deterioration immediately after surgery and 1 month later, as compared to preoperative motor status RESULTS: Immediately after surgery, 13 of 39(33%)patients in Group A, 6 of 17(35%)in Group B, and 7 of 8(88%)in Group C experienced deterioration of motor function. One month after surgery, 4 of 39(10%)patients in Group A, 3 of 17(18%)in Group B, and 4 of 8(50%)showed deterioration of motor function. Both immediately(χ2=8.3, p<0.05)and 1 month(χ2=6.9, p<0.05)after surgery, MEP alterations correlated significantly with postoperative deterioration of motor function. Despite MEPs being stable throughout surgery(Group A), there were some patients with deterioration of motor function initially appearing to represent false negative monitoring. However, these deteriorations were confirmed to have been caused by secondary hemorrhage, venous return dysfunction, postoperative convulsion, or resection of the supplementary motor area. CONCLUSIONS: MEP monitoring provides reliable information on the motor system during glioma surgery. Although false negative MEP results may exist in some patients, most data were not influenced by intraoperative manipulation but rather were attributable to secondary postoperative events.

Asunto(s)

Neoplasias Encefálicas/cirugía , Potenciales Evocados Motores/fisiología , Glioma/cirugía , Monitoreo Intraoperatorio , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos , Tractos Piramidales/cirugía , Resultado del Tratamiento , Adulto Joven

RESUMEN

OBJECTIVE: To evaluate the usefulness of transcranial motor evoked potential(MEP)monitoring for aneurysm surgery. METHODS: Sixty-four patients undergoing aneurysm surgery were included in the study. We recorded MEP responses at craniotomy, when dissecting the aneurysm and surrounding tissue, after clipping, and during temporary clipping of the parent artery. We examined the relations between MEP wave pattern change and postoperative motor function. RESULTS: In all of the patients MEPs were recordable for continuous neurophysiological monitoring of the vascular territory of interest throughout the surgery. In 16 patients, significant intraoperative MEP changes occurred. Of these patients, three patients presented with postoperative transient motor deficit. From the changes in MEP wave recording after aneurismal clipping and temporary occlusion of the parent artery. We speculated that the maximal time allowed for occlusion of the perforating arteries without ischemic damage is five minutes. Intraoperative MEP changes had a sensitivity of 100%(3/3)and specificity of 78.7%(48/61). The positive predictive value of postoperative motor deficit was 18.8%(3/16), and the negative predictive value was 100%(48/48). It was important to carry out MEP monitoring, so as not to produce false-negatives. CONCLUSIONS: Intraoperative transcranial MEP monitoring is useful for predicting motor function after aneurysm surgery.

Asunto(s)

Potenciales Evocados Motores/fisiología , Aneurisma Intracraneal/fisiopatología , Aneurisma Intracraneal/cirugía , Monitoreo Intraoperatorio , Adulto , Anciano , Craneotomía/métodos , Estimulación Eléctrica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Intraoperatorio/métodos

RESUMEN

BACKGROUND: To determine whether the monitoring of abnormal muscle response (AMR) and facial motor evoked potential (FMEP) during microvascular decompression (MVD) for hemifacial spasm (HFS) might be useful for predicting the postoperative clinical course and final outcomes. METHODS: We analyzed 45 HFS patients who underwent both AMR and FMEP monitoring during MVD. Patients were divided into two groups on the basis of post-MVD disappearance (group AMR-A) or persistence (group AMR-B) of AMR. With regard to FMEPs, patients were classified into one of the two groups according to the ratio of the final to baseline FMEP amplitudes recorded for the orbicularis oculi muscle: one group with a ratio of <50% (group FMEP-A), and the other with a ratio of ≥50% (group FMEP-B). RESULTS: Twenty-one of the 26 (81%) patients in group AMR-A were assigned to group FMEP-A, whereas 9 of the 17 (53%) patients in group AMR-B were assigned to FMEP-B (P < 0.05). In 38 of the 40 (95%) patients in whom the AMRs disappeared or persisted at amplitudes <50% that at the baseline, HFS had subsided at the final follow-up. Forty of the 42 (95%) patients whose FMEP amplitude ratios indicated reduction in the amplitudes from the baseline, had complete relief of the symptoms. Nineteen of the 20 (95%) patients whose AMRs disappeared after MVD experienced immediate relief of their symptoms after the operation. With regard to 14 of the 20 (70%) patients whose AMRs persisted at the final recordings, the symptoms of HFS improved over time and eventually subsided (P < 0.001). CONCLUSIONS: Intraoperative monitoring of both AMR and FMEP during MVD may be useful in predicting the postoperative outcomes in HFS patients. The AMR-related findings may help to predict whether HFS disappears immediately after surgery or some time later.

RESUMEN

BACKGROUND: In the surgeries of the upper part of the cerebellopontine angle (CPA), the petrosal vein (PV) is an obstacle, and the resection of the PV sometimes causes postoperative complications such as cerebellar hemorrhagic infarction. On the other hand, it can be an anatomical landmark during the surgery. We have used three-dimensional (3D) CT images for preoperative evaluation. We, herein, report 4 cases of CPA lesions. METHOD: The PV was imaged with neighboring structures using CT and a workstation. We paid attention especially to the vein of the cerebellopontine fissure (VCPF). RESULT: The four cases include one case of trigeminal neuralgia, two meningiomas and one case of acoustic schwannoma. 3D CT images showed (1) the anatomical formation such as course of the PV, (2) relationship to the neighboring structures of the tumors, (3) expectation of complications after sacrificing the PV. By observing the preoperative 3D CT images, we were able to plan safety operative approaches and procedures. CONCLUSION: 3D CT images of the PV are very useful for preoperative evaluation of surgery in CPA lesions.

Asunto(s)

Ángulo Pontocerebeloso/irrigación sanguínea , Ángulo Pontocerebeloso/cirugía , Venas Cerebrales/diagnóstico por imagen , Imagenología Tridimensional/métodos , Periodo Preoperatorio , Tomografía Computarizada por Rayos X/métodos , Cerebelo , Hemorragia Cerebral/prevención & control , Infarto Cerebral/prevención & control , Femenino , Humanos , Imagen por Resonancia Magnética , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/cirugía , Meningioma/diagnóstico por imagen , Meningioma/cirugía , Persona de Mediana Edad , Neuroma Acústico/diagnóstico por imagen , Neuroma Acústico/cirugía , Complicaciones Posoperatorias/prevención & control , Neuralgia del Trigémino/diagnóstico por imagen , Neuralgia del Trigémino/cirugía

RESUMEN

BACKGROUND: Giant distal anterior cerebral artery (DACA) aneurysms are extremely rare, with only 32 cases reported in the literature. Most giant DACA aneurysms have features that make standard neck clipping difficult, and bypass surgery is sometimes required, although this surgery was performed in only three reported cases. This report presents the fourth case treated with bypass surgery. CASE DESCRIPTION: A 69-year-old female presented with an unruptured thrombosed giant DACA aneurysm. She underwent wrapping operation 7 years before, but radiological imaging revealed enlargement of the aneurysm at the left pericallosal artery (PerA)-callosomarginal artery (CMA) junction. Before operation, three different strategies were considered for bypass surgery in case the neck could not be clipped. Aneurysm resection and left proximal PerA-CMA end-to-end anastomosis were successfully performed under intraoperative digital subtraction angiography (DSA) and motor-evoked potential (MEP) monitoring. CONCLUSION: Most DACA aneurysms are located at the PerA-CMA junction. In some cases, adequate retrograde flow to the distal PerA from the posterior or middle cerebral artery can be expected, making distal PerA reconstruction unnecessary. Moreover, when the distal PerA is cut, proximal PerA-CMA end-to-end anastomosis can be easily performed because of reduced tension in both vessels. We therefore conclude that this strategy should be utilized for treating such patients. We also presented here the effectiveness of intraoperative modalities, such as intraoperative DSA and MEP monitoring, for performing a safe operation.

RESUMEN

OBJECTIVE: To assess the usefulness of presurgical simulation of microvascular decompression (MVD) by virtual endoscopy (VE), a new tool to analyze three-dimensionally reconstructed magnetic resonance data sets in patients with trigeminal neuralgia or hemifacial spasm (HFS). METHODS: In 17 patients (10 with trigeminal neuralgia and seven with HFS) determined to be candidates for MVD, we performed presurgical simulation of MVD using VE. We used constructive interference in steady-state imaging and magnetic resonance angiography to obtain the original images. VE findings were compared with surgical findings. RESULTS: The three-dimensional relations between visible structures seen on VE were consistent with intraoperative findings in all patients. In total, 20 (91%) of 22 neurovascular compression sites in all 17 patients were correctly delineated on VE, with the exception of two small branches identified as offending vessel in two patients with HFS. Perforators that were not apparent on VE limited our ability to accomplish transpositioning of the offending vessels as simulated. The positions of structures that can affect individual surgical approaches, such as the petrosal vein, cerebellar flocculus, and vertebral artery, were also adequately predicted on VE. All patients had excellent surgical outcomes. CONCLUSION: Presurgical VE in patients with trigeminal neuralgia or HFS is a novel technique that provides excellent visualization of the three-dimensional relations between neurovascular structures and allows simulation of MVD.

Asunto(s)

Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Síndromes de Compresión Nerviosa/cirugía , Neuroendoscopía/métodos , Enfermedades Vasculares/cirugía , Adulto , Anciano , Descompresión Quirúrgica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes de Compresión Nerviosa/patología , Cuidados Preoperatorios , Neuralgia del Trigémino/patología , Neuralgia del Trigémino/cirugía , Enfermedades Vasculares/patología

RESUMEN

OBJECTIVE: To determine whether monitoring facial nerve motor evoked potentials (FNMEPs) elicited by transcranial electrical stimulation during skull base tumor surgery is useful for predicting facial nerve outcome. METHODS: We analyzed FNMEP findings in 31 patients with skull base tumor. Surgery was performed twice in 2 of the 31 patients because of tumor regrowth. FNMEP monitoring was conducted 33 times in the present study. Corkscrew electrodes positioned at C3 or C4 and Cz were used to deliver supramaximal stimuli (140-550V). FNMEPs were recorded from the orbicularis oculi and oris muscles. Correlation between the final-to-baseline FNMEP ratio and postoperative facial nerve function (House & Brackmann grade) was examined. RESULTS: Valid FNMEPs were obtained in 26 of the 33 (78.8%) recordings from the orbicularis oculi muscle and in 31 of the 33 (93.9%) recordings from the orbicularis oris muscle. Facial nerve function correlated significantly with the FNMEP ratios in the orbicularis oculi (r = -0.52 N=26, p < 0.01) and orbicularis oris (r = -0.60, N=31, p < 0.001) muscles. An FNMEP ratio of -50% consistently predicted immediate postoperative facial palsy, although the degree of palsy differed among the patients. CONCLUSIONS: Intraoperative FNMEP monitoring is useful for predicting facial nerve function after skull base surgery.

Asunto(s)

Potenciales Evocados , Nervio Facial/fisiología , Monitoreo Intraoperatorio/métodos , Estimulación Eléctrica Transcutánea del Nervio/métodos , Adolescente , Adulto , Anciano , Parálisis Facial/prevención & control , Femenino , Predicción , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/prevención & control , Pronóstico , Neoplasias de la Base del Cráneo/cirugía

RESUMEN

OBJECTIVE: We retrospectively analyzed various clinical factors to determine whether or not these factors are etiopathologically related to the development of hydrocephalus in patients with vestibular schwannomas. METHODS: There were 68 patients (29 men, 39 women) in this study who underwent resection of a vestibular schwannoma. The age at the time of surgery ranged from 19 to 76 years (mean age, 51.4 yr). The maximum diameter of the tumor in the cerebellopontine cistern ranged from 0 (localized within the internal auditory canal) to 56 mm (mean, 32.0 +/- 12.9 mm). Cerebrospinal fluid (CSF) protein concentration in the cerebellomedullary cistern was measured intraoperatively in all patients. RESULTS: Sixteen (23.5%) of the 68 patients exhibited radiographic evidence of hydrocephalus. Univariate analysis of various factors revealed that both tumor size and CSF protein concentration were positively related to development of hydrocephalus (P < 0.05 and P < 0.01, respectively). However, in multiple logistic regression analysis, only the CSF protein concentration was predictive for development of hydrocephalus (P = 0.022). There was a trend toward increased CSF protein concentration in patients with a large tumor (> or = 40 mm) compared with those with a small tumor (< 40 mm) (P = 0.06). CONCLUSION: A high CSF protein concentration in fluid from the cerebellomedullary cistern is one of the most important factors contributing to hydrocephalus associated with vestibular schwannoma. It is important to judge whether or not any further treatment is required for hydrocephalus, in addition to tumor resection, especially in patients with communicating hydrocephalus.

Asunto(s)

Neoplasias Encefálicas/complicaciones , Hidrocefalia/etiología , Hidrocefalia/patología , Neuroma Acústico/complicaciones , Adulto , Anciano , Neoplasias Encefálicas/líquido cefalorraquídeo , Femenino , Humanos , Hidrocefalia/líquido cefalorraquídeo , Masculino , Persona de Mediana Edad , Neuroma Acústico/líquido cefalorraquídeo , Neuroma Acústico/genética , Neuroma Acústico/cirugía , Proteínas/metabolismo , Estudios Retrospectivos , Estadística como Asunto , Tomografía Computarizada por Rayos X