1/14. Surgical indications and microsurgical anatomy of the transchoroidal fissure approach for lesions in and around the ambient cistern.OBJECTIVE: Opening the temporal part of the choroidal fissure (CF) makes it possible to expose the crural cistern, the ambient cistern, and the medial temporal lobe. We examined the microsurgical anatomy and the surgical indications for use of the trans-CF approach. methods: The microsurgical anatomy encountered in the trans-CF approach for lesions in and around the ambient cistern was studied in three cadavers. On the basis of these cadaveric studies, the trans-CF approach was used during surgery in three live patients with such lesions. RESULTS: The angiographic "plexal point," which indicates the entrance of the anterior choroidal artery as it enters the temporal horn of the lateral ventricle, was thought to be a key anatomic landmark of the trans-CF approach. A cortical incision for entry into the temporal horn should be made in the inferior temporal gyrus to minimize the potential damage to the optic radiations and to the speech centers. After the CF is opened posteriorly to the plexal point between the tenia fimbria and the choroid plexus, the posterior cerebral artery (PCA) in the ambient cistern can be observed with minimal caudal retraction of the hippocampus. In this study, surgical procedures using the trans-CF approach were successfully performed on patients with high-positioned P2 aneurysms whose PCA ran close to the plexal point or higher, whose medial temporal arteriovenous malformations were fed mainly by the PCA, and whose tentorial hiatus meningiomas protruded into the temporal horn through the CF, with no resulting postoperative visual or memory disturbances. CONCLUSION: The trans-CF approach is especially useful in surgery for lesions in and around the ambient cistern.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
2/14. Three-year recurrence-free survival in a patient with recurrent medulloblastoma after resection, high-dose chemotherapy, and intrathecal yttrium-90-labeled DOTA0-D-Phe1-Tyr3-octreotide radiopeptide brachytherapy.BACKGROUND: Most medulloblastomas express high levels of somatostatin type 2 receptors (sst2). DOTA0-D-Phe1-Tyr3-octreotide (DOTATOC) specifically binds sst2 in the low nanomolar range. The cytotoxic effect is mediated by the chelated, beta-emitting, metallic radionuclide yttrium 90 (90Y). The authors applied this innovative treatment option in a boy age 8 years who presented with a recurrent medulloblastoma of the cauda equina: a prognostically poor condition. Targeted radiotherapy was administered to treat minimal sst2-expressing tumor remnants, which persisted despite conventional and high-dose chemotherapy and intercurrent resection of the lesion. methods: A medulloblastoma arising from the floor of the fourth ventricle had been removed surgically; then, the patient was treated with standard adjuvant chemotherapy and craniospinal irradiation according to the prospective HIT '91 protocol. Complete remission was achieved for 20 months, when a drop metastasis of the cauda equina manifested with sensorimotor lumbosacral deficits and urinary incontinence. After four cycles of neoadjuvant chemotherapy (which consisted of combined ifosfamide, carboplatinum and etoposide), two cycles of high-dose chemotherapy and autologous stem cell transplantation were performed; in between, the responding residual tumor within the lumbosacral nerve fibers was microscopically removed. Thereafter, an indium-111-DOTATOC test injection indicated sst2-expressing tumor remnants within the cauda equina. Consequently, 4 cycles of [90Y]-DOTATOC (4x562.5 megabecquerels) were injected directly into the cerebrospinal fluid in monthly intervals. RESULTS: The consolidating intrathecal brachytherapy using [90Y]-DOTATOC was tolerated well. A complete remission was achieved for a 3-year period. The only remaining deficit was urinary incontinence. CONCLUSIONS: Intrathecal administration of targeted radiopeptide brachytherapy in combination with conventional and high-dose chemotherapy and surgical removal represents a promising new option to treat recurrent medulloblastoma and should be explored further.- - - - - - - - - - ranking = 25.498082554989keywords = cauda equina, equina, cauda (Clic here for more details about this article) |
3/14. mutism after cerebellar medulloblastoma surgery.The case of a 9-year-old boy is presented, who developed transient mutism after removal of a medulloblastoma in the region of the cerebellar vermis. The mutism disappeared within 6 months. Neither reduction of consciousness nor disturbances of caudal cranial nerves or phonation ever appeared. The case is discussed with regard to its phenomenology, pathogenesis, and etiology, corresponding case reports are also taken into consideration.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
4/14. Outcomes of surgical resection of large solitary hemangioblastomas of the craniocervical junction with limitations in preoperative angiographic intervention: report of three cases.INTRODUCTION: Hemangioblastomas of the central nervous system may occur sporadically, or in association with von Hippel-Lindau (vHL) disease. The treatment of large solitary hemangioblastomas of the posterior cranial fossa mandates a combination of angiographic intervention and surgery. However, large tumors may derive their vascularity from major cerebellar vessels, which can make their embolization hazardous. AIM: To describe the surgical outcomes of three cases of large hemangioblastomas with compression of the medulla oblongata, where the potential for preoperative embolization was extremely limited. CASES: Three patients (all males; 68, 36 and 38 years) presented with a history of chronic headache and caudal cranial nerve deficiencies. diagnostic imaging showed large vascular lesions (4 x 3, 4 x 5 and 5 x 5 cm) at the craniocervical junction, compressing the brainstem. There were no concomitant findings associated with vHL disease. TREATMENT: Staged treatment was administered. Preoperative embolization was attempted at first. One patient (68 yrs) showed a pica occlusion and associated cerebellar infarction after embolization; embolization was deemed hazardous in the other two. In the second phase, the lesions were removed via a midline suboccipital approach with resection of the arch of altas. Complete removal was possible in all three cases. POSTOPERATIVE COURSE AND FOLLOW-UP: The caudal cranial nerve deficiencies deteriorated soon after surgery in all three patients. A tracheotomy was required in two patients, which was removed uneventfully during the rehabilitation phase. Ventriculo-peritoneal shunts were implanted in two patients. MRI follow-up three (1 case) and four years (2 cases) after surgery showed no relapse. The Karnofsky Index scores were 80, 70 and 90 in the three patients aged 68, 36 and 38, respectively. CONCLUSION: Total microneurosurgical removal of large hemangioblastomas at the craniocervical junction with limited preoperative embolization (associated with morbidity) should be seriously considered. Although the early outcome is not encouraging, the long-term outcomes seem favorable.- - - - - - - - - - ranking = 2keywords = cauda (Clic here for more details about this article) |
5/14. Surgical management of anteriorly placed lesions at the craniocervical junction--an alternative approach.Lesions ventral to the neuraxis at the craniocervical junction can pose a significant management problem because of their strategic location. Conventional posterolateral approaches sometimes may not permit adequate visualization of the entire base of the tumor without significant manipulation of the brain stem and spinal cord. The anterior transoral and extrapharyngeal approaches are alternate ways of exposing this region without neural retraction. However, these approaches do not provide adequate exposure of the lateral margins of the tumour, there is no control of the vertebral arteries and cranial nerves and the tumor--brain stem interface is not seen till the end of the operation. A lateral approach is described in this report which involves additional bone removal in the region of the mastoid process and the articular pillars in order to provide a true lateral perspective for the removal of these tumors. The advantages include excellent definition of the interface between the tumor and cord/brain stem without manipulation of the neuraxis, control of the ipsilateral vertrebral artery and caudal cranial nerves, ability to remove the intra- and extradural portions of the tumor in one operation and the ability to perform an immediate bony fusion if necessary. The application of this approach in the management of 9 patients with a variety of intra- and extradural lesions at the clivus and foramen magnum is discussed.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
6/14. cerebellopontine angle epidermoid tumor extending into the upper cervical spinal canal--case report.A 61-year-old male with right facial pain and hearing loss was found to have a cerebellopontine angle epidermoid tumor that extended downward through the foramen magnum into the upper cervical spinal canal. The tumor was removed except for a small fragment of its capsule adherent to the brainstem. Only three such tumors with caudal extension have been reported.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
7/14. Bilateral trochlear nerve palsies. A clinicoanatomic correlate.A patient with bilateral trochlear nerve palsies is presented. Computed tomographic (CT) brain scan localized an anterior cerebellar vermis lesion compressing the area caudal to the inferior colliculi where the fourth nerves decussate and exit the dorsal brain stem. This lesion was probably responsible for the bilateral trochlear nerve dysfunction. Pertinent anatomy and pathologic involvement are discussed.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
8/14. Syrinx of the conus medullaris and filum terminale in association with multiple hemangioblastomas.A patient with multiple hemangioblastomas and syrinxes of the cerebellum and spinal cord is presented. An additional mass imaged at the L-3 vertebral level was identified by percutaneous syringography as a bilobular syrinx extending from the conus medullaris into the filum terminale. At surgery the syrinx was opened into the caudal cerebrospinal fluid space and the several hemangioblastomas excised. These spinal tumors all appeared to arise in juxtaposition to the posterolateral sulcus and dorsal sensory roots.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
9/14. Primary position upbeat nystagmus. A clinicopathologic study.eye movements were studied with electro-oculography in a patient with primary position, large amplitude, upbeat nystagmus. The upbeat nystagmus increased in amplitude on upward gaze, decreased on downward gaze, and was not altered by loss of fixation. The patient could not produce smooth pursuit movements upward or to the left, but had normal saccadic and vestibular induced eye movements in all directions. At necropsy, a low grade glioma was found involving primarily the medulla and caudal pons. The inferior olives and prepositus hypoglossal nuclei were diffusely infiltrated with tumor. These results suggest (1) primary position upbeat nystagmus is due to a defect in the upward smooth pursuit system, (2) the lower brain stem at the level of the inferior olives and nucleus prepositus hypoglossi is important in the mediation of vertical pursuit, and (3) primary position upbeat nystagmus can result from damage to several nuclei and interconnecting pathways in the caudal brain stem and midline cerebellum involved in control of vertical smooth pursuit.- - - - - - - - - - ranking = 2keywords = cauda (Clic here for more details about this article) |
10/14. Calcified basal ganglionic mass 12 years after radiation therapy for medulloblastoma.A patient treated 12 years previously with an operation and radiation therapy for a medulloblastoma developed weakness of the left hand and perivascular calcification involving the right internal capsule and caudate nucleus. These findings are considered possible long-term complications of the radiation therapy.- - - - - - - - - - ranking = 1keywords = cauda (Clic here for more details about this article) |
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