Dysphagia and dyspnea due to an anterior cervical osteophyte

Hypertrophic anterior cervical osteophytes have been reported as a cause of dysphagia, with about 100 cases described in the literature; on the other hand, chronic or acute dyspnea due to edema of the laryngeal inlet or bilateral vocal cord adduction-fixation is rare. We report a 57-year-old patient with a 2-year history of dysphagia and episodic dyspnea, who suffered sudden, severe respiratory distress necessitating emergency tracheotomy. A voluminous anterior cervical osteophyte at the C5 level was diagnosed by computed tomography (CT) and barium swallow test and removed by an anterior approach to the cervical spine, with clinical remission. The incidence, pathogenetic mechanisms, radiological diagnosis, and surgical indications of anterior cervical osteophytes associated with dysphagia and dyspnea are discussed. We advise examining cervical spine patients with dysphagia and/or dyspnea by radiography and CT when other investigations are not conclusive for a digestive or respiratory pathology.

Peduncular hallucinations associated with large posterior fossa meningiomas

Peduncular hallucinosis may be observed in patients with thalamic or brain stem ischemia or hemorrhage, while it has been less often described in association with brain stem or cerebellar tumors. We report in this paper two cases associated with large posterior fossa meningiomas. In the first patient hallucinosis appeared preoperatively as a result of brain stem compression and ceased after the tumor removal. In the second patient hallucinosis occurred after the surgery, as a result of surgical trauma with local brain stem edema, and ceased 4 days after treatment with desamethasone and carbamazepine.

Dural arteriovenous malformation associated with recurrent subdural haematoma and intracranial hypertension

An unusual case of intracranial hypertension and symptoms of a left parieto-occipital mass lesion due to a dural arteriovenous malformation (AVM) with a large and dilated draining vein is reported. The patient also had a history of homolateral recurrent subdural haematoma, 11 years before. Subdural haematoma is rarely associated to a dural AVM. We suggest that the recurrent subdural haematoma was due to the very slow and intermittent venous bleeding from the preexisting dural malformation, which progressively enlarged in the following years to become very large. The symptoms of intracranial hypertension and papilloedema may be explained by the increased pressure in the dural sinus and the cerebral venous system. On the other hand, focal neurological symptoms in our case resulted from the mass effect due to an aneurysmally dilated draining vein in the left parieto-occipital region.

Endoscopic surgery for pineal region tumors

Endoscopic surgery may play an important role in most patients with pineal region tumors. We report our experience with 5 patients treated by a burr hole endoscopic technique. The procedure included in all cases third ventriculostomy for the correction of hydrocephalus, CSF sample for cytology and tumor markers, and tumor biopsy for histological diagnosis. Endoscopic biopsies showed a pineocytoma in two cases, a germinoma in 2 and a low-grade astrocytoma in one. We agree that endoscopic surgery may allow us to select cases requiring a microsurgical approach (medium-sized or large non-germ-cell tumors) from cases to be treated only by irradiation and chemotherapy (germinomas and other non-germ-cell tumors). Then, in some patients with pineal region tumors the endoscopic procedure remains the only surgical treatment. When a direct microsurgical approach is indicated, it may be performed in a non-emergency situation and after correction of the hydrocephalus by endoscopic third ventriculostomy.

Endoscopic surgery for large posterior fossa arachnoid cysts

The authors report two cases of large arachnoid cysts of the posterior fossa treated by endoscopic surgery. One patient underwent a successful endoscopic cyst fenestration by burr hole approach after several procedures of shunt revision. In another an endoscope-assisted microsurgical intervention was necessary. Lateral (cerebellar or cerebellopontine angle) cysts, as two reported cases, may be treated through a lateral retromastoid approach by fenestration into the prepontine cistern and eventually into the cisterna magna. We advise to start the operation through a burr hole and to try to realize the fenestration by endoscopy only. If this attempt fails, an endoscope-assisted microsurgical technique may be performed by enlarging the craniectomy. In this last instance the endoscope is useful particularly deeply to fenestrate the anterior cyst wall in the prepontine or ambient cisterns, where it provides more illumination and helps to identify the nervous and vascular structures.

Cervical spine stenosis due to ossification of the posterior longitudinal ligament in Italian patients: surgical treatment and outcome

Ossification of the posterior longitudinal ligament (OPLL) of the cervical spine is a frequent pathological entity in people of Japanese and Asian extraction and is reported with increasing frequency also in the USA; on the contrary, reports in the European and particularly in the Italian literature remain rare. This paper describes 8 Italian patients with cervical spine stenosis due to OPLL extending three to five vertebral segments (and above C3 in four cases). Magnetic resonance imaging shows the extent of the ossification well in terms of height and cord compression, while computed tomography is useful to measure the thickness of the bone mass and the residual spinal canal. Anterior cervical decompression by discectomy, corpectomy, and removal of the ossified ligament is the treatment of choice and results in clinical improvement in most cases. Decompressive laminectomy may be reserved for patients with ossification extending to four or five levels and above C3. The surgical technique and intraoperative findings are discussed.

Ossification of the yellow ligament causing thoracic cord compression

Ossification of the yellow ligament (OYL) is not infrequent in the cervical and lumbar regions but is very rare in the thoracic spine, with no more than 40 cases reported in the literature. We describe a 50-year-old male with progressive paraparesis and sensory dysfunction, secondary to OYL at T10-T11, studied by computed tomography (CT) and magnetic resonance imaging (MRI). Decompressive laminectomy and removal of the ligament resulted in marked clinical improvement. Patients with OYL may initially develop sensory dysfunction associated with leg weakness. This pathological entity can be well defined by CT and MRI, and surgery by decompressive laminectomy is advised for all cases. The OYL should be removed both posteriorly and laterally to the dural sac to obtain sufficient decompression of the spinal canal.

Endoscopic treatment of para- and intraventricular cerebrospinal fluid cysts

This study has been made to define the role of endoscopy and the most appropriate approach and technique of endoscopic fenestration of paraventricular and intraventricular CSF cysts according to the cyst size and location. Twenty-two patients with intraventricular (13 cases) and paraventricular (9 cases) CSF cysts, operated upon by endoscopic technique in three Italian neurosurgical centers, are reviewed. Paraventricular hemispheric cysts have been treated by endoscopic fenestration from the cyst to the lateral ventricle. Midline intraventricular cysts (2 of the septum pellucidum and 4 of the velum interpositum) underwent fenestration from the right lateral ventricle to the cyst, with fenestration in both lateral ventricles in one case. Cysts of the choroid plexus have been fenestrated from the homolateral enlarged ventricle (4 cases) or from the contralateral compressed ventricle (2 cases). Twenty patients (more than 90%) were definitively cured by the endoscopic procedure, whereas only 2 patients required a shunt or a direct approach. We think that the endoscopic fenestration must be considered the treatment of choice of intraventricular and paraventricular CSF cysts.

Intraoperative sonography for spinal tumors. Correlations with MR findings and surgery

BACKGROUND

To investigate the role of intraoperative ultrasonography during surgery for spinal tumors and the correlation between echographic, magnetic resonance and surgical findings.

METHODS

Twenty patients with spinal tumor, explored by MRI of the spine, have been treated with ultrasound-guided surgery. The ultrasound exploration has been performed during laminectomy on the dural surface in all cases and, after the dural opening, on the spinal cord surface for intramedullary tumors.

RESULTS

In all patients the ultrasound exploration has allowed to exactly define the extent of the laminectomy, the dural opening and the myelotomy. Meningiomas were hyperechoic and homogeneous, with well defined margins and often visible hyperechoic dural attachment; neurinomas were less hyperechoic and less homogeneous than meningiomas. Intramedullary tumors showed hyperechoic solid and hypoechoic cystic-necrotic components, although a specific tissue characterization (tumor infiltration, gliosis, edema) is not possible.

CONCLUSIONS

Intraoperative ultrasonography should be used routinely during surgery for spinal tumors in order to reduce the extent of the laminectomy, dural opening and myelotomy. A good correlation exists between signal intensity on T1-weighted images of MR, the echographic aspect of the tumor and the pathological findings at operation.

Endoscopic third ventriculostomy for hydrocephalus

The authors report on 125 patients who underwent endoscopic third ventriculostomy for obstructive hydrocephalus in three Italian Neurosurgical Centers. The series includes 77 cases of primary aqueductal stenosis, 33 with triventricular hydrocephalus due to external tumor compression, and 15 with tetraventricular hydrocephalus. The operations were carried out mainly under general anesthesia, using a flexible endoscope. Decrease of size of the third ventricle and the presence of a signal void at the level of the fenestration are the main postoperative MRI findings. Signs of intracranial hypertension, increased head circumference and Parinaud syndrome respond more frequently to the endoscopic treatment. The overall rate of good results (shunt-independent patients) in this series is 86.4%; primary aqueductal stenosis (93.5%) and triventricular hydrocephalus due to external compression (84.8%) are associated to the higher rate of good postoperative results than tetraventricular hydrocephalus (53.3%). Because of the very low invasivity of this technique, the absence of postoperative mortality and the scarce and usually transient postoperative complications, the authors advise to enlarge the indications for endoscopic third ventriculostomy to all patients with obstructive hydrocephalus when the third ventricle is large enough and there are no alterations of the CSF resorption.

Endoscopic surgery for monoventricular hydrocephalus

BACKGROUND

Monoventricular hydrocephalus is usually treated with extrathecal shunting. However, today endoscopic fenestration of the septum pellucidum seems to be a very useful and less invasive technique.

METHODS

Five patients with monoventricular hydrocephalus have been treated with neuroendoscopic techniques. In three cases with an excluded lateral ventricle due to contralateral shunt overdrainage, the normal-sized ventricle was first cannulated and fenestration of the septum pellucidum from the normal to the enlarged lateral ventricle was performed.

RESULTS

Complete remission of intracranial hypertension symptoms and decrease in size of the enlarged ventricle were observed in all five patients.

CONCLUSIONS

Endoscopic fenestration of the septum pellucidum is the technique of choice for treating monoventricular hydrocephalus. We advise first cannulating the normal lateral ventricle and then performing a septostomy from it to the enlarged ventricle. This approach allows one to easily recognize the protruding septum pellucidum and perform fenestration without difficulty using a direct trajectory. In exceptional cases of choroid plexus cyst obstructing one foramen of Monro, fenestration of the cyst wall is sufficient.

Intracranial meningiomas: correlations between MR imaging and histology

The authors have examined the relationship between magnetic resonance imaging (MRI) and histopathological features in 35 surgically verified intracranial meningiomas. Tumor signals on T1-weighted images were rather similar regardless of the histologic subtype of the tumors. On T2-weighted images, hypointense meningiomas were mainly fibroblastic and hyperintense tumors were mainly syncytial and angioblastic, and partly transitional. Isointense tumors were mainly transitional and partly fibroblastic and syncytial. The authors conclude that the signal intensity of the MRI may be useful in the preoperative characterization of intracranial meningiomas. T1-weighted images may predict the presence of cysts and intratumoral blood vessels; whereas T2-weighted images can give information about histological subtype, vascularity and consistency. Meningiomas hyperintense to the cortex on T2 are usually soft, more vascular and more frequently of syncytial or angioblastic subtype; tumors hypointense or hypo-isointense on T2 tend to have a more hard consistency and are more often of fibroblastic or transitional subtype.

Chronic hydrocephalus and suprasellar arachnoid cyst presenting with rhinorrhea

Spontaneous CSF leak with rhinorrhea may be secondary to many intracranial congenital and acquired conditions. However, no cases of chronic hydrocephalus and suprasellar arachnoid cyst presenting with rhinorrhea as the unique clinical manifestation are reported in the literature. A 29-year-old-man with four-month history of episodic rhinorrhea had a large suprasellar arachnoid cyst with chronic hydrocephalus on magnetic resonance. Endoscopic ventricular fenestration of the cyst failed to obtain remission of the CSF leak, because it was not possible to fenestrate the cyst with the almost completely obliterated suprasellar cistern. Clinical remission occurred after restoration of the CSF flow from the cyst to the cisternal spaces by a direct approach. The CSF leak in this case was secondary to the chronic compression over the dural and bone structures of the sellar region by the cyst or chronic hydrocephalus.

Endoscopic surgery for intracranial cerebrospinal fluid cyst malformations

Endoscopic surgery represents a new and very useful modality of treatment for intracranial cysts. The authors review the cases of 19 patients with intracranial malformative CSF cysts (seven intraventricular, six paraventricular, and six arachnoid) who underwent endoscopic fenestration by using a burr-hole approach. The various endoscopic approaches and techniques of fenestration, according to the type and location of the cyst, and the causes of unsuccessful outcome are critically discussed. The authors recommend endoscopic fenestration as the treatment of choice for patients with para- and intraventricular cysts, in whom the procedure may help to avoid the microsurgical approach and shunt placement in nearly all patients. In patients with arachnoid cysts, the endoscopic procedure, although associated with a lower rate of successful outcome, may be performed as the primary procedure in most cases because it is a minimally invasive procedure; the traditional surgical treatment may be performed without additional risk in which endoscopic surgery has failed.

Endoscopic surgery for intracranial cerebrospinal fluid cyst malformations

Endoscopic surgery represents a new and very useful modality of treatment for intracranial cysts. The authors review the cases of 19 patients with intracranial malformative CSF cysts (seven intraventricular, six paraventricular, and six arachnoid) who underwent endoscopic fenestration by using a burr-hole approach. The various endoscopic approaches and techniques of fenestration, according to the type and location of the cyst, and the causes of unsuccessful outcome are critically discussed. The authors recommend endoscopic fenestration as the treatment of choice for patients with para- and intraventricular cysts, in whom the procedure may help to avoid the microsurgical approach and shunt placement in nearly all patients. In patients with arachnoid cysts, the endoscopic procedure, although associated with a lower rate of successful outcome, may be performed as the primary procedure in most cases because it is a minimally invasive procedure; the traditional surgical treatment may be performed without additional risk in which endoscopic surgery has failed.

Territories of the perforating (lenticulostriate) branches of the middle cerebral artery

The territories of the central branches of the middle cerebral artery (MCA) were examined in 21 injected human brains. It was noted that these central arteries supplied: the caudate nucleus (dorsolateral half of the rostral part of its head; the entire caudal part of the head; the body and rostral portion of the tail in some cases), the putamen (dorsolateral part of its rostral portion, the remainder of the putamen, except the most caudal part occasionally), the globus pallidus (the entire lateral segment, except the ventrorostral and, sometimes, the most caudal part), the basal forebrain (lateral parts of the basal nucleus of Meynert and the nucleus of the diagonal band, as well as fiber bundles in this region), the internal capsule (dorsal and ventrocaudal part of the anterior limb, dorsal part of the genu, dorsal and ventrorostral part of the posterior limb), the corona radiata (a narrow strip close to the internal capsule) and the cerebral cortex (the caudal orbitofrontal cortex occasionally). The presented data may have certain neuroradiologic, neurologic and neurosurgical significance.

Pituitary macroadenoma and diaphragma sellae meningioma: differential diagnosis on MRI

Diaphragma sellae meningiomas are unusual tumours often not distinguished from pituitary macroadenomas. Preoperative differentiation is essential, because the trans-sphenoidal approach is used for surgical removal of adenomas, while meningiomas are approached via a craniotomy. We reviewed five patients in whom a diaphragma sellae meningioma was initially diagnosed as a nonsecreting pituitary macroadenoma. MRI criteria for differential diagnosis are discussed. The main findings considered are visibility of the pituitary gland, contrast enhancement, the centre of the lesion and sellar enlargement. These criteria, applied to a blind review, allow correct identification of the tumours.

Anomalous meningeal branches of the ophthalmic artery feeding meningiomas of the brain convexity

Many anomalies may involve the ophthalmic and middle meningeal arteries, because of the close relationship of their development. The system of the ophthalmic artery may supply the dural convexity by the middle meningeal artery of ophthalmic origin, the anterior branch of the middle meningeal artery or an accessory meningeal artery. The development and the anatomic arrangement of these anomalous vessels are discussed. Three cases of meningiomas of the brain convexity supplied by anomalous meningeal arteries arising from the ophthalmic artery are described. In one case internal carotid angiography showed an anomalous anterior branch of the middle meningeal artery arising from the ophthalmic artery, whereas the maxillary artery provided only the posterior branch of the middle meningeal artery. In two cases the middle meningeal artery system was normal, but the ophthalmic artery provided an accessory meningeal artery supplying the meningioma. Whereas an ophthalmic origin of the middle meningeal artery is rather common, the angiographic finding of an accessory meningeal artery or an anterior branch of the middle meningeal artery arising from the ophthalmic arterial system is exceptional. The preoperative embolization of dural lesions supplied by anomalous meningeal vessels of ophthalmic origin is dangerous because of the risk of embolization into the ophthalmic circle.

Olfactory groove meningioma with paranasal sinus and nasal cavity extension: removal by combined subfrontal and nasal approach

A very unusual case of olfactory groove meningioma with recurrence extending into the paranasal sinuses and nasal cavities, 15 years after the first transcranial operation, is described. The patient was successfully treated by a combined subfrontal and nasal approach. Large downward extension of an olfactory groove meningioma into the nasal cavities is a rare event, with no or isolated cases reported even in large series of these tumours. The nasal extent of these meningiomas is more often asymptomatic, although signs of sinus obstruction and epistaxis have been described. Although small paranasal sinus extensions of the meningioma may be removed by the transcranial route, a combined subfrontal and nasal approach is necessary in cases with large tumour masses extending into the nasal cavities, as in our own one.

The oculomotor nuclear complex in humans. Microanatomy and clinical significance

This study has been performed to define better the anatomical structure of the oculomotor nuclear complex and its neuronal components. The oculomotor nuclear complex was examined in fixed and serially sectioned midbrains from 12 adult subjects free from neurological diseases. The complex included the somatic portion, (formed by multipolar motor neurons), and the parasympathetic portion, (formed by oval or fusiform preganglionic cells), on each side of the median raphe. The somatic portion consisted of the lateral somatic cell column and the caudal central nucleus. The somatic column measured from 0.2 x 0.1 mm to 3.4 x 1.4 mm (X = 2.4 x 1.2 mm) in transverse section. It was divided into the principal, intrafascicular and extrafascicular parts. The principal part was subdivided into the dorsal, intermediate and ventral portions. Isolated multipolar neurons were also found in the periaqueductal gray matter, the interstitial nucleus of Cajal, the Edinger-Westphal nucleus and the fibre bundles of the oculomotor nerve. These cells most likely represent the displaced motor neurons of the oculomotor nerve. The caudal central nucleus was 0.8 x 0.6 mm in size. The Edinger-Westphal nucleus consisted of the rostral, ventral and dorsal parts; the longest rostrocaudal diameter of this nucleus measured 7.1 mm. The anatomical data of our study are relevant clinically and allow explanation of the neurologic signs following complete or partial lesions of the oculomotor nuclear complex.

Neuroendoscopy. Personal experience, indications and limits

The authors report a series of 40 patients treated by endoscopic neurosurgery. It includes 31 cases of obstructive hydrocephalus, 4 paraventricular or intraventricular CSF cysts, 3 cases of multiloculated hydrocephalus, one suprasellar arachnoid cyst and one cystic astrocytoma with mural tumor nodule. Third ventriculostomy is the most frequent indication of the endoscopic neurosurgery, which is very useful also for performing fenestration of CSF cysts and multiloculated hydrocephalus. The surgical endoscopic techniques in the different above mentioned pathologies are exposed. The criteria for patient selection, the clinical results and the postoperative radiological findings, that confirm the patency of the fenestration, are discussed.

Arachnoid cyst of the lateral ventricle

BACKGROUND

Arachnoid cysts rarely occur within the lateral ventricles, with only 10 reported cases in the literature. They may arise from the arachnoid layer that is present in the choroidal fissure.

CASE DESCRIPTION

This 25-year-old man with headache and a left jacksonian seizure had an intraventricular arachnoid cyst of the right occipital horn and trigone found on radiologic examination by computed tomography (CT) and magnetic resonance imaging (MRI). He was successfully treated by evacuation of the cyst and removal of its wall through a right parietooccipital craniotomy. Histologic studies of the cyst wall confirmed the presence of arachnoid cells and connective tissue.

CONCLUSIONS

Arachnoid cysts of the lateral ventricles occur in the occipital horns and trigone (all but 1 of 10 cases) in young patients with symptoms of intracranial hypertension. MRI well defines the relationship of the cyst with the ventricular wall. Surgical removal of the cyst wall or cystoperitoneal shunt have been successfully performed in the reported cases; however, endoscopic fenestration of the cyst must be considered today as the treatment of choice.

Supratentorial cavernous malformations and epilepsy: seizure outcome after lesionectomy on a series of 35 patients

Epilepsy is the most frequent presenting sign in patients with cavernous angiomas and is the major cause of morbility. Persistence of seizures after surgical treatment prompted many authors to examine the possibility of removing the cavernoma and the surrounding tissue. In our series of 53 cavernous angiomas, all the 35 patients with preoperative seizures underwent surgery by means of lesionectomy alone. One hundred percent of patients with less than five preoperative seizures and/or an history under 12 months was seizure free, while only 62.5% of patients with more than five seizures and/or an history longer than 12 months was seizure free. Number and duration of seizures before surgery seems to be the most important factor in the seizure outcome after surgical treatment.

Spondylodiscitis. Clinical and magnetic resonance diagnosis

STUDY DESIGN

This study reviews 65 patients with spondylodiscitis, both spontaneous and postoperative and of different etiology, studied by magnetic resonance imaging.

OBJECTIVES

To define the magnetic resonance imaging characteristics of infections of the spine in acute and chronic stages and to evaluate the role of magnetic resonance imaging in defining their etiology.

BACKGROUND DATA

Early diagnosis of spondylodiscitis is often difficult because of the long latent period. Radiographs of the spine, bone scan, and computed tomography scan provide insufficient data.

METHODS

Among 65 patients with spondylodiscitis studied by magnetic resonance imaging, 24 were examined in the acute stage (clinical evolution between 7 days and 20 days), and 41 were examined in the chronic stage (3-6 weeks). The etiologic agent was staphylococcus in eight cases, Brucella in 13, Mycobacterium tuberculosis in 29, Salmonella in four, and unknown in 11.

RESULTS

In cases observed in the acute stage, the disc and the vertebral bodies were hypointense in T1 and hyperintense in T2; this relatively constant finding was not correlated with the etiologic agent. In the chronic stage, cases caused by Brucella or of unknown etiology showed long T1 and T2 relaxation times, with precocious contrast enhancement of the disc; in cases of tubercular etiology there was slight shortening of T1, with inhomogeneous enhancement of the involved vertebral bodies and late disc enhancement.

CONCLUSIONS

Magnetic resonance imaging is the investigation method of choice in diagnosing spondylodiscitis, especially in very early stages of the disorder, when other investigations still yield negative results. In chronic stages, magnetic resonance imaging also allows tubercular spondylodiscitis to be distinguished from cases of different etiology.

The role of intraoperative sonography in reducing invasiveness during surgery for spinal tumors

The authors describe the ultrasound-guided surgical approach to 20 spinal tumors (13 extramedullary and 7 intramedullary). Intraoperative sonography (IOS) is important to reduce the extent of the laminectomy and dural opening, thus avoiding useless removal of bone structures. In cases of intramedullary tumors, IOS defines the extent of the posterior myelotomy, the presence of syringomyelic cavities caudal and/or cranial to the tumor and the deep extension of the tumor to the anterior cord surface. For these reasons, the routine use of IOS during surgery for spinal tumors reduces the surgical invasivity of this approach. The advantages and limits of the ultrasound-guided spinal surgery and the operative ultrasonographic findings of different spinal neoplasms are discussed.

Coiling of the vertebral artery presenting with neuralgic pain

A rare case of radicular pain in the arm due to compression of the C6 nerve root by coiling of the vertebral artery is reported; the diagnosis was confirmed by computed tomography (CT), magnetic resonance (MR) angiography and echocolordoppler. Although the enlargement of an intervertebral foramen by a tortuous vertebral artery has been described previously, the occurrence of radicular pain is exceptional. Magnetic resonance imaging (MRI), MR angiography and echocolordoppler allow to differentiate foraminal enlargement due to vascular anomalies of the vertebral artery from that more commonly due to tumor compression, mainly from neurinoma. Surgical decompression may be considered in symptomatic cases.

Cyst of the velum interpositum treated by endoscopic fenestration

BACKGROUND

The cavum veli interpositi is a not infrequent radiologic finding in both children and adults, as confirmed by computed tomography (CT) and magnetic resonance (MR). A moderate enlargement of the cavum may sometimes be observed; on the other hand, a true large cyst may be considered exceptional, with only one reported case.

CASE HISTORY

This 9-year-old boy with psychomotor retardation and epileptic seizures had a large CSF cyst in the region of the cavum veli interpositi, diagnosed by CT and MR. The patient was treated by endoscopic surgery, with introduction of the endoscope into the occipital horn of the right lateral ventricle and multiple fenestrations from the right ventricle to the cyst, and then from the cyst to the left lateral ventricle. The surgery resulted in decrease in the size of the cyst and reduction of the frequency of seizures.

DISCUSSION AND CONCLUSIONS

Children with dilated or cystic cavum veli interpositi present with a large head, mental retardation, seizures, and hydrocephalus. On CT and MR, the cyst shows a typical triangular configuration on the axial plane and lies on the roof of the third ventricle in the coronal plane. Endoscopic ventricular fenestration is the treatment of choice for these as well as all other intraventricular and intracerebral CSF cysts, because it ensures communication between the cyst and the ventricular system and avoids definitive shunting of the cyst.

Symptomatic subependymomas of the lateral ventricles. Report of eight cases

Subependymomas are rare, slow-growing, benign intraventricular tumors, which often are asymptomatic and are discovered incidentally. The review of the literature shows more than 100 symptomatic cases, less than half located in the lateral ventricles. Here we report 8 cases of symptomatic subependymomas of the lateral ventricles, studied by CT and/or MR and treated by direct surgical approach. The suspicion of a subependymoma should arise when a patient older than 10-15 years with long clinical history presents an intraventricular tumor isodense on CT and isointense in T1 and hyperintense in T2 on MR, with scarce or discrete contrast enhancement. Surgical treatment is indicated in symptomatic subependymomas of the lateral ventricles and usually allows complete tumor removal. The prognosis is usually good, also without postoperative irradiation.

Endoscopic ventricular fenestration of intracranial fluid cysts

The authors report 5 patients with paraventricular or intraventricular fluid cysts, successfully treated by fenestration into the ventricular system using a neuroendoscopic technique. The series includes three paraventricular malformative CSF cysts, a cyst of the velum interpositum and a cystic astrocytoma with small, deeply located and unresectable mural nodule. In all cases the endoscopic fenestration was the unique treatment and allowed to avoid the definitive ventriculoperitoneal shunt. The surgical endoscopic technique and the postoperative radiological findings which indirectly confirm the patency of the fenestration are discussed. The authors conclude that endoscopic ventricular fenestration represents the treatment of choice for most paraventricular and intraventricular CSF collections.

Fronto-ethmoidal and orbital osteomas with intracranial extension. Report of two cases

Osteomas involving the anterior cranial base are quite rare lesions. Intracranial and orbital extension of these tumors, causing neurological and ophthalmological symptoms and signs is a rare event. Two such cases are reported. In the first one, the tumor arose from the frontal sinus and extended upward to the medial and superior wall of the right orbital cavity and the lower part of the right frontal convexity. In the second case the osteoma arose from the left orbital roof and extended to the lower part of the homolateral frontal convexity and the splenoid wing. After the operation the symptoms disappeared and the cosmetic deficits were corrected. Skull-films, CT and MR well define the bony extension and the displacement of the orbital and intracranial structures. Indications to the surgery include progressive ophthalmologic and neurologic signs and significant cosmetic deformations. The surgical techniques and the postoperative complications are briefly discussed.

Giant spinal cord ependymoma in a child. Case report

Ependymomas of the spinal cord extending to more than ten vertebral segments are rare. A case of a 14-month-old child is described and the other 13 reported cases are reviewed. The finding of a very extensive tumor (from T5 to L5) after only 14 months of life suggests that in our case the tumor was present since birth. Magnetic resonance well shows the real extent of the tumor in height and its different components. Complete removal is often possible even in very extensive ependymomas and results in clinical improvement. Postoperative radiotherapy is necessary only for incompletely removed or malignant ependymomas.

Intracranial meningeal melanocytoma: case report

A case of meningeal melanocytoma of the left sphenoid wing is reported and the other nine cases in the literature are reviewed. Meningeal melanocytoma is a benign melanotic tumor that derives from the melanocytes of the leptomeninges and may occur anywhere in the cranial and spinal meninges. Electron microscopy well demonstrates melanin and melanosomes within the tumor cells. The immunohistochemical pattern of this tumor includes strong positivity for S-100 protein, vimentin, and antimelanoma antibody and negativity for epithelial membrane antigen, neuron-specific enolase, cytokeratin, and glial fibrillary acidic protein. Complete surgical removal is the treatment of choice, whereas radiotherapy is usually unnecessary. In spite of benign biologic behavior of meningeal melanocytoma, the prognosis remains uncertain, because of the possible local recurrences.

[Solitary capillary hemangioblastoma, cellular variant. Clinical, radiological, and anatomo-pathological study of 2 cases]

Two cases of the rare cellular variant of the solitary capillary haemangioblastoma are reported. On MR study both tumors appeared as cerebellar contrast-enhancing masses, without evidence of intra- or perilesional blood vessels. Histologically, they showed compact groups of polygonal or rectangular cells separated by compressed small capillaries. There were no reticulin fibres among cell clusters. The stromal cells were found to be immunopositive for neuron-specific enolase (NSE), factor VIII-related antigen (von Wille-brand factor), Ulex europaeus lectin, and glial frillary acidic protein (GFAP). The findings are discussed in light of the pertinent literature.

'De novo' aneurysm formation: report of two cases

We report 2 cases of 'de novo' aneurysm formation in a vessel which appeared to be normal at a previous angiography. The first patient developed an anterior communicating artery aneurysm nine years after occlusion of the right internal carotid artery by Gianturco coils for the treatment of a giant intracavernous carotid aneurysm. In the second case a 'de novo' aneurysm of the internal angle A1-A2 segment of the left anterior cerebral artery developed 6 years after successful clipping of another aneurysm of the same location. De novo formation of an aneurysm in a vessel which was found to be normal in a previous angiographic study, may occur as result of hemodynamic changes, such as after internal carotid occlusion or in presence of an arteriovenous malformation or variations of the circle of Willis. However, definite hemodynamic changes may also be absent. We conclude that patients operated on for aneurysm clipping must be periodically explored by magnetic resonance angiography to evaluate the possibility of de novo appearance of another aneurysm.

Central neurocytoma: clinico-pathological study of 5 cases and review of the literature

Five cases of central neurocytoma, confirmed by immunohistochemical and electron microscopy studies, are reported and 127 cases from the literature are reviewed. Central neurocytomas are more frequent than previously thought, and will be diagnosed with increasing frequency in the future, if intraventricular tumors with histological aspect of oligodendroglioma or ependymoma will be routinely studied by immunohistochemistry and electron microscopy. The occurrence of an intraventricular tumor with a typical MR aspect in a young patient should suggest preoperatively the diagnosis of neurocytoma. The positivity for synaptophysin and neuron specific enolase, the negativity for neurofilament protein and glial fibrillary acid protein, and the finding of elements of neuronal differentiation on electron microscopy, are the main pathological features of these tumors. Complete removal of the tumor mass without radiotherapy is the treatment of choice. The prognosis is usually favorable without recurrence.

Post-radiation cerebral lesions in adults

For many years, the human brain was considered relatively resistant to therapeutic doses of radiation. With the increasing length of survival of patients irradiated for brain tumors, there have been reported long-term effects of radiation therapy due to inappropriate dosage, period of delivery, fractionation or field. Thus, randomized studies are needed both to optimize the radiation therapy technique than to integrate new therapeutic modalities into the management of patients with primary brain tumors.

Intraplaque hemorrhage of the carotid arteries: diagnosis by duplex scanning

Eighty-three patients with intraplaque hemorrhage of the carotid arteries, explored by Duplex scanning, are reported; 36 among them were also studied by digital angiography and 28 were operated on. The echographic aspect suggesting the presence of an intraplaque hemorrhage is that of a hypo-anechogenic stria separating the intimal plaque from the media-adventitia complex. On the contrary, the angiographic findings are aspecific and unrelated to the presence of intramural blood clots. We think that duplex scanning is the investigation of choice in detecting intraplaque hemorrhage of the carotid arteries. The role of other radiological techniques, such as computed tomography of the neck and magnetic resonance, is also discussed.

Correlation between sex hormone receptors and peritumoral edema in intracranial meningiomas

Fifty patients with intracranial meningiomas, verified histologically, are retrospectively analyzed to correlate the peritumoral brain edema with the positivity of estrogen receptors and progesterone receptors. The extent of edema was quantified on CT scan and/or MR. Monoclonal antibodies were used to test the estrogen receptors and the dextran-coated charcoal method was used to test the progesterone receptors. Significant levels of both receptors were found in 41 (82%) specimens. 80% of the cases with positive receptors had brain edema, in contrast to only 2 among 9 cases with negative receptors. Thus, the presence of brain edema has resulted to be correlated to the positivity of sex hormone receptors, although we did not find significant correlation between the amount of receptors and the amount of edema. The suggested mechanisms responsible for the brain edema surrounding intracranial meningiomas are discussed. We can suggest that progesterone may induce the secretion of some substances from meningioma cells, such as prostaglandins and biogenic amines, which may result in vagogenic edema.

Cerebral hemorrhagic complication in polyarteritis nodosa. Case report and review of the literature

Polyarteritis nodosa (PN) is frequently cause of both central and peripheral neurological disorders. However, involvement of the central nervous system is rare at the beginning of the disease. In this paper we report a case of a 38-year-old woman hospitalized in our Neurosurgical Service because of left hemiparesis in presence of cutaneous arteritis (PN). At computed tomography (CT) an intracerebral hemorrhage was found. No radiographic evidences of vasculitis of the visible arterial branches, at angiography, were seen. Cerebral arteritis should be suspected as a cause for intracranial hemorrhage in patients without hypertension or other risk factors.

Cerebellar medulloblastoma in adults: report of 15 cases and review of the literature

From 1974 to 1988, 15 adult patients (aged over 16 years) with cerebellar medulloblastomas were observed in our Neurosurgical Department. All were treated by total (8 patients) or subtotal (7 patients) resection of the tumor, followed by radiation therapy to the posterior cranial fossa, spine and whole brain. A 5-year survival was achieved in 7 patients (46.6%). Local tumor recurrence occurred in 4 patients. The best treatment and the factors that influence the prognosis and survival of adult medulloblastomas are discussed also from the analysis of the pertinent literature.

Hydatid cyst of the lumbosacral spine with large pelvic mass

A rare case of hydatid cyst of the lumbosacral spine, causing extensive destruction of the sacrum and a large pelvis mass, is reported; a cutaneous fistula from the pelvic cavity to the posterior lumbar region was also present. The patient was studied by computerized tomography and operated on by combined anterior and posterior approach. The sacral localization of the spinal hydatidosis and its extension into the pelvic cavity are unusual. CT and MR allow a good definition of the bone destruction and the abdominal and pelvic extensions. Radical removal of spinal hydatid cysts may be rarely accomplished, because of the extensive bone invasion, and multiple recurrences, requiring repeating operations, occur in most cases.

Long-term survival of low-grade astrocytomas of the cerebral hemispheres

The authors have reviewed 6 patients operated on, with histologically proven diagnosis of grade-II astrocytomas who have survived more than 10 years even with many reoperations. Young age, pre- and postoperative neurological status, aspect of the tumor mass on CT and MRI, site of the tumor in non-high functional areas and extent of surgical removal are the most important variables in predicting length of survival. In young patients without severe neurological deficits and with astrocytic tumors located in non high-functional areas, very long survivals may be obtained even with many operations, when the interval between the recurrences is at least three years.

Spontaneous cure of a ruptured intracranial aneurysm

A rare case of spontaneous cure of an internal carotid artery aneurysm is reported; the progressive resolution of the spasm and the disappearance of the aneurysm have been confirmed by serial angiograms respectively performed two weeks, two months and four months after the hemorrhage. The other 14 reported cases of angiographically documented spontaneous cure of intracranial aneurysms are reviewed and the possible causes of spontaneous aneurysmal thrombosis, such as retarded cerebral circulation, arterial spasm, size of the neck, thrombosis of the feeding artery and antifibrinolytic therapy, are discussed.

Rapid growth of a brain-stem cavernous angioma

A rare case of rapidly enlarging cavernous angiomas of the cerebral hemispheres and brain stem in a child is reported. Rapid growth of cavernous malformations of the brain is rarely observed; it may be due to different mechanisms, including enlargement of the vascular channels, hemorrhage and cysts formation. The possibility of progressive enlargement of cavernomas makes periodical MR studies necessary in all cases. When the growth is radiologically documented, surgical removal is imperative even in patients with trivial symptoms.

Megadolichobasilar anomaly. Clinical and diagnostic considerations on 30 cases

30 patients with megadolichobasilar artery, explored by angiography, are reported; 23 among them were first studied by computerized tomography and 4 by magnetic resonance. From the clinical point of view, 9 had transient ischemic attacks or definitive ischemia, 7 had subarachnoid or intracerebral hemorrhage, and 7 had deficits of the cranial nerves; in the other 7 cases the condition was incidentally discovered as isolated asymptomatic anomaly or with other unrelated lesions. Among the patients with ischemic symptoms, vertebrobasilar insufficiency and pontine infarction were the most common clinico-radiological findings. Among the patients with intracranial hemorrhage, four had associated aneurysm or arteriovenous malformations. CT and MR allow a correct diagnosis of this anomaly. MR seems to be superior to CT in delineating the relationship of the anomalous artery with the nervous structures, and the coexisting pathology.