Microsurgical clipping versus newer endovascular techniques in treatment of unruptured anterior communicating artery-complex aneurysms: a meta-analysis and systematic review

The aim of this study is to compare occlusion rate, complication rate, and clinical outcome of microsurgical clipping (MC) and advanced endovascular techniques (EVT) in unruptured anterior communicating artery-complex aneurysms (ACoCAs). We reviewed the scientific literature reporting occlusion rate, time of occlusion assessment, and clinical outcome of MC and EVT in patients with unruptured ACoCAs, from January 2009 to December 2019. We included in our analysis 25 studies and 872 patients with unruptured ACoCAs (434 treated with endovascular techniques and 438 with MC). Ninety-three (10.7%), 320 (36.7%), 21 (2.4%), and 438 (50.2%) were treated with flow diverter (FD), stent-assisted coiling (SAC), endosaccular devices (ES), and microsurgical clipping (MC) respectively. FD, SAC, ES, and MC subgroups presented minor complications in 11.8%, 3.8%, 14.3%, and 7.1% of cases (p=.016), and major complications in 3.2%, 4.4%, 0%, and 7.1% (p=.136) of patients. A total occlusion rate post-treatment has been achieved in 4.3%, 87.1%, 47.6%, and 98.2% of cases (p=.000), while at 12 months' follow-up in 50%, 66%, 83.3%, and 80% of patients (p=.001). FD, SAC, ES, and MC subgroups had a good clinical outcome at 12 months in 93.5%, 90.5%, 100%, and 67.8% of cases. MC is associated with higher post-treatment total occlusion rate, but higher complication and lower good clinical outcome rates. EVT are promising in treating unruptured anterior cerebral artery aneurysms with high margin of safety and good clinical outcome, despite the lower total occlusion rate.

A comparison of acute vascular damage caused by ADAPT versus a stent retriever device after thrombectomy in acute ischemic stroke: a histological and ultrastructural study in an animal model

Background

It has been amply demonstrated that endovascular procedures can be successful treatment for stroke, both in terms of revascularization and clinical outcome. There is not, however, a published comparison of any histological or ultrastructural damage to the vessels that may be caused by a direct aspiration first pass technique (ADAPT) or stent retrievers (SR) used in these procedures. This study analyses and compares acute damage to the arterial wall caused by ADAPT or SR.

Material and methods

Damage to the walls of swine extracranial arteries was evaluated after ADAPT with the Penumbra system or thrombectomy with an SR (Solitaire 6×30). The procedures were performed after injecting thrombi into the selected arteries (arteries with diameters similar to those of the human internal carotid artery and first segment of the middle cerebral artery). After the procedures, the animal was euthanized and 12 arterial samples were obtained for analysis by optical and electronic microscopy.

Results

Tissue samples from the vessels treated with SR showed almost complete loss of endothelium, thickening of the internal elastic lamina, and degeneration of the elastic fibers of the bordering lamina media and adventitia. In contrast, tissue samples of the vessels treated with ADAPT had a clear integral internal elastic lamina and uninterrupted endothelial lining, although cell alignment was altered and there were surface lacerations due to manipulation of the samples.

Conclusions

Both techniques caused acute damage to the vessel walls, however, thrombectomy with SR appeared to be more harmful to all layers of the arterial wall, particularly the endothelium.

A Systematic Review and Meta-Analysis of Treatment and Outcome of Blister-Like Aneurysms

BACKGROUND AND PURPOSE

Blister-like aneurysms are uncommon but challenging lesions. Their small size and atypical location often make the diagnosis difficult. Microsurgery and endovascular procedures have been used for their treatment, but there is no consensus on the best treatment technique. We conducted a systematic review and meta-analysis of treatments and outcomes of these vascular lesions.

MATERIALS AND METHODS

We reviewed English-language articles on "blood blister-like aneurysms" published between January 1997 and November 2014. All studies reporting patients with these aneurysms treated with surgery, endovascular procedures, or combined therapy with data on treatment modalities and clinical and/or angiographic outcomes were selected, including case reports and series. We performed a meta-analysis on the 2 largest treatment groups (surgery and endovascular management).

RESULTS

Sixty studies with 334 patients met our inclusion criteria. Surgery was performed in 114 patients (34.2%), and endovascular treatment, in 199 patients (59.5%). A combined treatment was used in 19 patients (5.7%). A favorable outcome (mRS 0-2) was reported in 67.4% and 78.9% of patients treated with surgery and with endovascular therapy, respectively (P = .034).

CONCLUSIONS

Blister-like aneurysms are challenging vascular lesions. The choice of treatment method must be based on the initial clinical presentation and an analysis of the radiologic features of the lesion to select the best technique. Endovascular treatment seems to have lower morbidity and mortality and provides a better outcome compared with surgical approaches. Further prospective studies must be performed to confirm such interesting results.

Does recurrent laryngeal nerve anatomy condition the choice of the side for approaching the anterior cervical spine?

AIM

The anterior cervical presternocleidomastoid approach is a safe and standardized procedure. Nevertheless, in all the largest series presented in literature, a certain risk of injury to the recurrent laryngeal nerves (RLNs) is reported and the choice of the side of the approach seems to influence such risk. Our aim was to study the surgical anatomy of the RLNs and to understand whether the side of the approach can be a risk factor for their surgical damage.

METHODS

We performed an anatomical dissection of 6 fresh cadavers, studying the origin and the course of both the RLNs, to assess their vulnerability in the anterior presternocleidomastoid approach to the cervical spine.

RESULTS

The origin of the right RLN was at C7 in 2 cases and at T1 in 4 cases. In all cases it arose where vagus nerve crossed the subclavian artery and it was directed superiorly and transversely to the esophagotracheal groove.

CONCLUSIONS

The right and left RLNs have different origin and course. Although the discussion about the best side for the anterior cervical approach is debated, in our opinion, both anatomical and surgical considerations, concerning RLNs, lead to the evidences that the left side approach, when possible, should be preferred below the level of C4.

Surgical exposure of lateral orbital lesions using a coronal scalp flap and lateral orbitozygomatic approach: clinical experience

BACKGROUND

The lateral extraconal compartment is a typical localization of intra-orbital tumours. With the exception of anterior lesions, which can be reached by a transconjuntival route, most of these tumours are currently approached through the classic lateral orbitotomy originally described by Kronlein. We present here our experience in the management of lateral orbital lesions, using a coronal skin flap, followed by subfascial dissection of the temporalis muscle. The procedure was intended to overcome the potential drawbacks associated with the classic transtemporal approach.

METHODS

The approach was used in eleven patients harbouring bone lesions of the lateral orbital wall or intra-orbital lesion of the lateral extra-ocular compartment. The postoperative results were assessed using a simple cosmetic outcome scale, which evalutated the temporalis muscle trophism and the function of the frontotemporal branch of the facial nerve.

RESULTS

All lesions were satisfactorily exposed. The subfascial dissection of the temporalis muscle is a key manoeuvre which, at the same time, abolishes the risk of injury to the frontotemporal branch of the facial nerve and provides a wide exposure of the lateral orbital wall. The cosmetic outcome was excellent in 9 patients and good in 2 patients.

CONCLUSIONS

The reported technique is a convenient surgical option to approach lateral intra-orbital lesions, with a minimal cosmetic impact.

Ghost lesions in patient with cerebral-isolated neurosarcoidosis. A case report

We present a case of isolated cerebral neurosarcoidosis with remitting nodular lesions resembling intraventricular neoplasms. The patient, admitted at our Department for surgical treatment of a magnetic resonance imaging (MRI) demonstrated fourth ventricle lesion, presented acute intracranial hypertension. A second MRI performed before the scheduled operation showed the disappearance of the fourth ventricle lesion and a tetra-ventricular hydrocephalus. The patient has been treated with a third-ventriculostomy, followed, after 15 days, by ventriculoperitoneal shunt. High doses of steroids have been administered. Cerebrospinal fluid analysis has been conducted and a high concentration of ACE, specific marker of neurosarcoidosis, has been found. No biopsy was performed to avoid surgical complications. A systemic chemotherapy with azathioprine has been started, but the patient died six months later for worsening of the clinical conditions. The autopsy confirmed the diagnosis of neurosarcoidosis. This is the first MRI documented case of neurosarcoidosis with remitting lesions. Diagnosis of isolated neurosarcoidosis is difficult and it is based on clinical and radiological exclusion of other entities. CSF examination is useful for diagnosis, for the reported specificity and sensibility of ACE. Medical treatment is based on corticosteroids and chemotherapic agents. Neurosurgical intervention can be related to treat hydrocephalus due to ependymal and arachnoidal involvement or to remove large lesions. In our opinion biopsy should be limited only to ACE negative patients and to those who do not respond to chemotherapy.

Spinous process marking: a reliable method for preoperative surface localization of intradural lesions of the high thoracic spine

Surgical exposure of intradural lesions in the thoracic spine requires intraoperative landmarks to identify the vertebral level. If spinal neuronavigation is not available, the surgeon must rely on alternative localizing methods. Intraoperative fluoroscopy is traditionally used to count the vertebrae throughout the whole spine. In the high thoracic spine, counting the vertebrae is often hampered by the scapular shadows. In these cases, a preoperative marking procedure seems preferable. Magnetic resonance imaging (MRI) based techniques have been increasingly reported, but they share an intrinsic risk of error due to the skin shift occurring at the time of surgery. We describe here a simple technique for unequivocal identification of the vertebral target. In six patients undergoing surgery for intradural lesions of the high thoracic spine, the spinous process of the vertebra corresponding to the lesion was preoperatively identified on an anteroposterior radiograph view and marked infiltrating its tip with a blue dye. At surgery, the vertebral target was identified easily and immediately. No errors occurred. No complications related to the technique were observed. Preoperative marking of the vertebral spinous process with a coloured dye is a simple and unequivocal guide to expose intradural lesions in the high thoracic spine.

Progressive quadriparesis in adolescent with stenosis of the cervical spine

INTRODUCTION

Progressive quadriparesis in adolescents suffering from cervical stenosis is a very rare entity. Only three cases have been reported in the literature.

CASE REPORT

We report our own case of progressive quadriparesis in a young patient suffering from cervical stenosis, the first to be documented with pre- and postoperative magnetic resonance imaging.

Ethylene oxide sterilization of autologous bone flaps following decompressive craniectomy

INTRODUCTION

In patients undergoing decompressive craniectomy, the bone flap is temporarily preserved either in the subcutaneous tissue of the patient or frozen. However, there are some drawbacks related to these methods.

MATERIAL AND METHODS

In 16 patients in whom the bone flap was removed for decompressive craniectomy, the bone was firstly washed in hydrogen peroxide and then placed in hermetically-sealed bags and sterilized using ethylene oxide. The bone was repositioned after an average period of 4.3 months.

RESULTS

One patient sustained an infection of the surgical wound which required permanent exclusion of the bone flap. In all the others, esthetic and functional results were good after an average follow-up of 20 months. Control CT-scan of the bone flap demonstrated preservation of its structural features with fusion of the bone margins and revitalization of the flap. On MRI a subdural space was again visible.

CONCLUSIONS

Sterilization of the bone flap with ethylene oxide in patients undergoing decompressive craniectomy avoids some of the drawbacks related to the techniques currently used. The easiness, low cost, good aesthetic and functional results of this procedure make it a valid alternative to other techniques for preservation of autologous bone in decompressive craniectomies.

Radiation-induced schwannomas of the nervous system. Report of five cases and review of the literature

Radiation therapy has important delayed effects on the central nervous system. Prominent among these effects is radiation necrosis of nervous tissue, but an oncogenic effect is also recognized. Both benign and malignant intracranial tumors can develop in irradiated fields, particularly in children. Most of these tumors are sarcomas, meningiomas or gliomas and only occasionally schwannomas. We report 5 cases of postirradiation acoustic nerve schwannoma observed in our Department.

Reconstruction of suboccipital craniectomy with autologous bone chips

BACKGROUND

In patients submitted to suboccipital craniectomy in whom the bone is not repositioned, there may be a significant aesthetic defect due to lack of bone tissue, sometimes accompanied by paresthaesia and painful symptoms.

METHOD

In 15 patients submitted to suboccipital craniectomy, the bone chips were repositioned during wound closure.

FINDINGS

At a mean follow up of 19 months (from 6 to 36 months), 2 patients (13%) complained of mild wound discomfort or occasional local pain. Twelve patients underwent control CT-scan. In three cases (25%) the bone fragments had been partly reabsorbed whereas in the other 9 (75%) they either formed a thin (4 patients) or consistent (5 patients) bony wall, with variable degree of adaptation to the contour of the contralateral occipital bone. The best cosmetic and functional results were obtained in young patients in whom the cerebellar parenchyma was well-preserved, as opposed to those in whom a CSF collection had replaced areas of cerebellar tissue.

INTERPRETATION

In the majority of cases in whom an osteoplastic suboccipital craniotomy is not possible, repositioning of the bone chips from suboccipital craniectomy is able to restore a bone table, thus allowing morphological and functional recovery of the occipital region.

Atypical tentorial meningioma 30 years after radiotherapy for a pituitary adenoma

Although the human central nervous system used to be considered relatively resistant to the carcinogenic action of ionizing radiation, several lines of evidence now document a high incidence of secondary tumors in irradiated patients. The numerous reports of radiation-induced cerebral meningiomas generally distinguish those induced by high-dose radiation from those induced by low-dose radiation. We describe the case of patient who underwent subtotal resection of a chromophobe pituitary adenoma at the age of 18 years, who was successively treated by conventional fractionated radiotherapy with gamma rays emitted by a source of 60Co until a total dose of 41 Gy. Over the next 30 years the patient experienced all the known late effects of radiation, including panhypopituitarism, cranial-nerve deficits (II, III and VI), massive radiation necrosis involving the left cerebral hemisphere and causing right hemiparesis and aphasia and, ultimately, an atypical tentorial meningioma with early recurrence after total resection.

Intraparenchymal haemorrhage after evacuation of chronic subdural haematoma. Report of three cases and review of the literature

Three cases of intracerebral haemorrhage following removal of a chronic subdural haematoma are reported and the literature on this topic reviewed. The possibility of an increase in cerebral blood flow following removal of CSH, makes slow, gradual decompression mandatory in all patients submitted to cranial trapanation.

Occipitocervical pseudomalignant osseous tumor of the soft tissue (Fasciitis ossificans). Case report

The authors describe the case of a 12-year-old girl in whom a pseudomalignant osseous tumor of the soft tissue was diagnosed. The lesion was resected, and at 3-year postresection follow-up examination, neuroradiological studies demonstrated no recurrence of the tumor.

Spontaneous acute subdural hematomas. A clinical comparison with traumatic acute subdural hematomas

A comparison was made between factors influencing survival in patients operated on for acute spontaneous subdural hematomas (ASSH) and other groups of patients operated for acute, post-traumatic, subdural hematoma reported in the literature. The data of 17 patients operated on for ASSH were collected. Four variables: early surgical treatment, high Glasgow Coma Scale score on admission, pupillary reactivity and age were statistically analyzed. The most significant factors for good outcome, in order of importance, were early surgical treatment, a high Glasgow Come Scale score on admission, good pupillary reactivity and younger age. The prognostic factors in non-traumatic and traumatic acute subdural hematomas were found to be identical.

Chronic subdural haematomas in patients aged under 50

The clinical findings in 31 patients with chronic subdural haematoma (CSH), aged between 20 and 50, are described. Aetiopathogenetic factors responsible for the formation of CSH match those of patients aged over 50 with CSH. A history of cranial trauma was present in 77% of the cases. In the remaining patients, a defect of haemostatic mechanisms was responsible for the subdural blood collection. On the computed tomography (CT) the haematoma generally appears as a thin subdural layer. The reliability of magnetic resonance imaging for detection of CSH makes it the most desirable investigation in such patients. Prognosis is influenced by preoperative clinical status and by the disease responsible for the formation of CSH.

Supratentorial hemangioblastoma in a patient with breast cancer. A case report

Patients with breast cancer may develop cerebral metastasis. Radio- and chemotherapy are advocated as an alternative to surgery in such patients. A woman operated on for breast cancer 2 years earlier developed a cerebral lesion. A definite preoperative diagnosis of the lesion was not possible on the basis of CT and MRI findings. The lesion proved to be a supratentorial hemangioblastoma. Neurosurgical treatment is recommended for patients with breast cancer who present a cerebral lesion, since a correct diagnosis may only be possible in the operating theater.

Immediate postoperative CT to assess the correct positioning of a ventricular catheter

Positioning of the ventricular catheter is safe using standard techniques, but in some cases there may be failure of a shunt because of incorrect placement. We carried out CT at the end of the surgical operation on 10 patients who had undergone cerebrospinal fluid shunting while still anaesthetized. In three cases a malpositioned catheter was detected. Immediate reoperation allowed readjustment of the ventricular catheter. Early postoperative CT appears to be useful for verifying correct placement.

Cavernous angiomas of the brain stem. Intra-axial anatomical pitfalls and surgical strategies

BACKGROUND

We review the surgical anatomy of the brain stem in relation to the surgical approaches adopted for treatment of cavernomas and identify possible "safe entry zones" on the anterior face of the brainstem.

METHODS

Twelve symptomatic patients with cavernoma or telangectasia of the brain stem were surgically treated. The brain stem was divided into the following anatomical areas: ventral medulla, dorsal medulla, dorsal pons, ventral pons, ventral mesencephalon, and dorsal mesencephalon, so that the surgical approach could be "individualized" according to the position of the cavernoma, the nerve fasciculi and nuclei.

RESULTS

On the anterior surface of the brain stem a medullar paramedian oblique access to the anterolateral sulcus and a paramedian sagittal pons access seem to avoid the main nerve fasciculi and nuclei.

CONCLUSIONS

Although the parenchymal window produced by the cavernoma is the most important parameter for the choice of approach, fairly safe entry zones may be identified even on the anterior surface of the medulla and pons.

Gunshot wound of the atlas in a youth

The case of a bullet retained, without causing neurological symptoms, in the anterior arch of a youth's atlas after a gun had been fired a short distance from his mouth is reported. The patient was managed with external stabilization.

Chronic subdural haematoma: a possible relationship with tamoxifen

Five patients operated on between 6 months and 7 years earlier for breast cancer were surgically treated for chronic subdural haematoma. This unusual association may be explained on the basis of known factors such as coagulative impairment subsequent to chemotherapy, a degree of cerebral atrophy or mild trauma. On the other hand, since four of the patients were taking antioestrogen therapy to control the disease, it is speculated that the oestrogenic properties of tamoxifen may have contributed to subdural bleeding.

Primary benign tumors of the orbital cavity: comparative data in a series of patients with optic nerve glioma, sheath meningioma, or neurinoma

BACKGROUND

Patients operated on for the most common benign pathologies of the orbital cavity-optic nerve glioma, sheath meningioma and neurinoma-should be surgically treated. However, postoperative visual impairment is frequently inevitable. A wait-and-see policy due to a slow rate of growth of these lesions is criticized.

METHODS

Collecting data from three series of patients operated, we compare the surgical procedures and long-term results.

RESULTS

"En bloc" removal in patients with optic nerve glioma led to complete visual deficit but ensures excellent long-term prognosis. Because optic nerve meningiomas are typically circumferential to the optic nerve and adhere tightly to the perineural pial microvascular structures, it is impossible to avoid trauma to the optic nerve and recurrences. Patients with neurinoma of the orbital cavity have the most favourable prognosis both in terms of visual function as well as long-term quality of life. Due to its slow rate of growth, a wait-and-see policy can be adopted for optic nerve glioma before deciding on surgical removal, whereas surgical treatment of meningioma may be postponed if symptoms are slight and steady. Removal of orbital cavity neurinoma should not be postponed since surgical outcome is excellent.

Tinnitus and hearing loss in pineal region tumours

The authors report an underestimated symptom and sign arising in pineal region tumours: tinnitus and hearing loss. It has been observed in 13 out of 72 pineal region tumours (18%). Three illustrative cases are reported in this paper. The inferior colliculi, the structure more dense in fibres than any other auditory brain stem site and at which majority of the acoustic pathways relay, is closely adjacent to the pineal body. Displacement of this structure may be responsible for acoustic symptoms together with common visual symptoms.

Familial hypercholesterolemia and intracavernous venous spilling of cholesterol in a child with large suprasellar dermoid cyst. Case report

A unique case of suprasellar dermoid cyst and familial hypercholesterolemia in a child is reported. Such an association, which strengthens the congenital hypothesis of dermoid cysts, could be a manifestation of a complex dyslipidemic inherited syndrome, at least in children. Surgical removal of the dermoid cyst which spilled cholesterol into the cavernous and intercavernous sinuses, allowed reduction of cholesterol levels in the postoperative period.

Homogeneous stromal cell population from normal human adult bone marrow expressing alpha-smooth muscle actin filaments

BACKGROUND

Hematopoietic microenvironment has a crucial role homing and regulating precursor cell growth both in physiologic and pathologic conditions. Fibroblast, endothelial cells, macrophages, adipocytes, and myoid cells, are the cellular component recognized in human bone marrow cultures. The presence of myoid cells in human bone marrow has been observed during fatal life, whereas during adult life, it is strictly related to pathologic conditions.

EXPERIMENTAL DESIGN

The aim of this study was to isolate a homogeneous stromal cell population. The mononuclear fraction obtained from the vertebral body of living humans was cultured without hydrocortisone and horse serum to inhibit foam cell differentiation.

RESULTS

The immunocytochemistry and electron microscopy characterization indicate that the cellular population we isolated had an homogeneous "myoid" differentiation. Moreover, these cells were able to support blast cell colony formation in vitro.

CONCLUSIONS

This method allowed the preparation of homogeneous myoid cell cultures depleted of other bone marrow stromal components. The isolation of a single stromal population is relevant in order to study the function of contractile filaments in allowing close-binding interactions with hematopoietic precursor cells.

Surgical management of orbital cavernous angiomas: prognosis for visual function after removal

The authors report the outcome of surgical treatment in a group of 25 patients with cavernous angioma of the orbital cavity. In the majority of cases, good esthetic results were appreciable within a few days of surgery. However, the onset or deterioration of preexisting visual deficits, in spite of the complete preservation of the optic nerve in a third of these patients, draws attention to the need for accurate surgical timing.

Long-term evaluation of asymptomatic patients operated on for intracranial epidermoid cysts. Comparison of the diagnostic value of magnetic resonance imaging and computer-assisted cisternography for detection of cholesterin fragments

Magnetic resonance imaging (MRI) and/or computer-assisted cisternography (CAc) assessment of latent late recurrences in long-term asymptomatic patients surgically treated for intracranial epidermoid cyst is here presented. MRI was exclusively utilized in one patient; CAc was exclusively employed in three patients with metalic operative clips; both CAc and MRI were employed in another four patients. CAc appears to be more reliable than MRI in detecting cholesterin fragments in asymptomatic patients operated on for intracranial epidermoid cyst.

Mucoceles of the paranasal sinuses with intracranial and intraorbital extension: report of 28 cases

Twenty-eight patients received surgical treatment for a paranasal sinus mucocele with intracranial and/or intraorbital extension. The lesions were classified by site and extension: anterior without intracranial extension (Type 1), 7 patients; anterior with intracranial extension (Type 2), 11 patients; posterior midline without intracranial extension (Type 3), 5 patients; and posterior with intracranial extension (Type 4), 5 patients. The surgical approaches were: transnaso-orbital, transfrontonaso-orbital, transsphenoidal, transmaxillosphenoidal, and subfrontal transbasal; the choice depended on the site and extension of the lesion, with the aim of securing maximum exposure to ensure total removal of the lesion with its capsule. A transcranial approach was reserved for mucoceles possessing an intracranial extension or causing distension of the bone structures with optic pathway neurological symptoms. With a coronal or transfacial skin incision along the lines of the forehead, nose, and orbital muscles of expression and careful reconstruction, the patients' natural cast of features was spared or restored in a single operation.

Management of intramedullary tumours in children

Clinical presentation, diagnosis, surgical technique and results of 25 cases of intramedullary tumours in patients under 16 years of age are analyzed. Pre-operative spinal deformity was present in 9 patients. Surgery was performed in all. After multilaminectomy with preservation of the intervertebral joints, total removal of the lesion was achieved in 11 patients and subtotal removal in 14 others. After surgery, external immobilization lasting an average period of 5 years was instituted in all patients. Postoperative radiation therapy was performed in 11 cases (5 "high grade" astrocytomas, 5 ependymomas, 1 glioblastoma). There were 11 recurrences: 4 of which (2 ependymomas and 2 "low grade" astrocytomas) were treated surgically, 7 (5 "high grade" astrocytomas, 1 glioblastoma, 1 oligodendroglioma) with palliative radiation treatment. Six patients eventually developed postlaminectomy spinal deformities as diagnosed roentgenographically 6 to 50 months postoperatively. Of the 16 patients still alive, 7 did not present relevant neurological deficit, 1 presented a monoparesis, while the other 8 presented invalidating deficits. Surgical treatment did not differ from that employed in the intramedullary tumours in the adult: radical resection is indeed the optimal therapeutic origin. The risk of radiation therapy are greater in children: it is crucial to limit radiation therapy to only some histotypes. The incidence of spinal column deformity after multilevel laminectomy is greater in young patients. It is advisable to implement prevention of spinal deformities by postoperative external immobilization and constant follow-up so as to detect early changes of spinal stability.

Giant intracranial mucocele secondary to osteoma of the frontal sinuses: report of two cases and review of the literature

Two cases are reported in which the growth of an osteoma of the frontal sinuses led to the formation of a secondary lesion, an intracranial mucocele, with marked mass effect.

Cholesterol granuloma of the cerebello-pontine angle

An unusual case of cholesterol granuloma of the temporal bone is described presenting as a cerebellopontine tumor. This lesion seemed to arise from an inflammatory process obstructing pneumatized cells. It consists of extradural granulation tissue and must be distinguished from intradural epidermoid cyst, which is, instead, a dysembryogenetic neoplasm. Simple drainage of the granuloma was accomplished by posterior fossa approach, but the lesion recurred after a year. The diagnosis and surgical management of cholesterol granuloma are discussed.

Cervico-medullary junction hemangioblastomas. Report of two cases and review of the literature

Reporting two cases of dorsally located cervico-medullary hemangioblastomas the Authors discuss clinico-biological features, diagnosis and therapy of this vascular neoplasms, analyzing the cases reported in detail in the available literature. In this site the tumor has often an exophitic development, adhering more or less extensively to the posterior surface of medulla oblungata, where progressively creates a niche. Transient neurogenic arterial blood hypertension, by possible involvement of the dorsal nucleus of vagal nerve, together with the lack of postoperative respiratory disturbances constitute the main clinical features of differentiation with intraaxial hemangioblastomas of the brainstem. Actually MRI represents the radiological investigation of choice, even if angiography still plays an important role in the correct preoperative diagnosis of hemangioblastomas. The therapy of dorsally located cervico-medullary hemangioblastomas is the total removal of the lesion also in asymptomatic patients, being the late surgical results generally successful.

Dermoid and epidermoid cysts of the midline in the posterior cranial fossa

Clinical features and surgical outcome of 16 patients with dermoid or epidermoid cysts on the midline of the posterior cranial fossa are compared. Salient points in the comparison are the younger age, presence of associated malformations and better prognosis of dermoid cyst.

Pulmonary embolism in neurosurgical patients

We report the outcome of a retrospective study on the frequency of pulmonary embolism during the hospital stay in a series of 7,250 neurosurgical patients. Of 4,500 patients who underwent surgery 25 (0.55%) developed pulmonary embolism at some point after the operation while 5 of the 2,750 patients not operated on (0.18%) developed a fatal pulmonary embolism. We analyze the general risk factors--age, sex, length of stay and paralysis of the limbs. Meningioma was the most frequent intracranial tumor to be affected by this complication. We discuss the connection between thromboembolism and meningioma.

Cerebral hydatidosis in childhood: a retrospective survey with emphasis on long-term follow-up

We report the long-term outcome of surgery for cerebral hydatid cyst in 12 children. In only one child, who had been operated on for cardiac hydatidosis a year earlier, was the brain cyst known to be secondary. Of the 12 children, 10 had a single cyst and 2 had multiple cysts. Five single cysts were removed intact by "hydatid birth," two cysts--one single and one multiple--were removed after puncture and aspiration of the cyst fluid, and the other five--four single and one multiple--were accidentally ruptured in the course of the operation. One patient died of infection of the residual space, 2 died of intracranial recurrence of the parasite (7 and 22 months later, respectively), and one, the child with secondary cerebral echinococcosis, died 6 years later of systemic echinococcosis. Eight patients who had a mean follow-up of 28 years are still living and enjoy very good health, both general and neurological. This long-term follow-up with such good results confirms the usually primary character of cerebral hydatid disease, at least in children. The combination of patent ductus arteriosus and ingestion of unboiled animals' milk might well explain how primary cerebral hydatid disease develops in children.

Transtentorial epidermoid cysts

Epidermoid cysts may occur simultaneously above and below the tentorium. Eleven patients with involvement of both infra- and supra-tentorial cisterns are presented. In two cases the epidermoid, located mainly in the cerebello-pontine angle, spread into the middle cranial fossa; in three the epidermoid extended from the parasellar cisterns to the posterior cranial fossa; in six patients the epidermoid, enlarging the tentorial notch, occupied extensively both cranial fossae. The surgical approach was influenced both by the experience of the surgeon and by the main extension of the epidermoid. Total removal was feasible in two patients only but only one of the eleven patients had a recurrence of the epidermoid. The long term results appear to be unrelated to the size of the epidermoid and to the choice of approach.

Cystic acoustic schwannomas

Three cases with large space-occupying cysts in the cerebellopontine angle are reported. CT and MRI findings were not typical for acoustic schwannomas but at operation, besides the large cysts, small acoustic schwannomas could be detected and removed. The clinical and neuroradiological features of this unusual variety and the CT and MRI differential diagnosis of cerebellopontine angle lesions are discussed.

Supratentorial dermoid cysts

Supratentorial dermoid cysts are rare lesions. In eight cases presented here, the lack of recurrence after subtotal removal of the capsule and the good long-term prognosis are emphasized. This finding is in agreement with the literature. The frequent relationship of these lesions with the cavernous sinus suggests a vascular genesis in the development of intracranial dermoid cysts.

Posttraumatic intradiploic leptomeningeal cyst in an adult: case report

We report the case of an adult with a posttraumatic intradiploic leptomeningeal cyst that caused a circumscribed osteolytic skull lesion. Local pain, the only symptom of the lesion, regressed after surgery. Intradiploic leptomeningeal cysts must be distinguished from intradiploic arachnoid cysts, which are of congenital origin.