Anteriorly placed tumors to the conus: removal by interradicular window.

Tumors anteriorly situated to the medullary conus are rarely encountered and represent a true surgical challenge. We examined the literature on this topic, concluding that there are no previous reports on alternative surgical techniques different to the traditional one. We report two cases of intradural extramedullary tumor operated on by a technique performed through a window opened between the spinal roots, which allows an easy, effective and useful resection. We describe a new operative technique which ensures a complete removal of these tumors and discuss clinical implications in the light of the available literature on this topic.

Spontaneous carotid-cavernous fistula supplied by the contralateral meningohypophyseal trunk: case report and literature review.

Carotid-cavernous sinus fistulas (CCF) are abnormal communications between the carotid artery and the cavernous sinus. Most spontaneous CCFs are low-flow fistulas, supplied by branches of the omolateral internal carotid artery or the external carotid artery. A 64-year-old man, with increasing diplopia, mild exophthalmos on the left side, blurred left vision and omolateral red eye, was admitted to our institution. The patient underwent a bilateral cerebral angiography that showed a left CCF fed by meningo-hypophyseal branches of the right internal carotid artery and draining from the cavernous sinus into a parahippocampal vein. A transarterial embolization of the carotid-cavernous fistula was performed, with complete obliteration of the fistula. Although anecdotal reports exist, there is a scarcity of well-documented cases of exclusively contralateral flow in the carotid-cavernous fistula. Most of the reported cases referred to contralateral flow into the carotid-cavernous fistula by the external carotid artery branches. To the best of our knowledge, there are no previous cases of a spontaneous CCF supplied by contralateral meningo-hypophyseal branches. A discussion of treatment options and a literature review are also performed.

Acute subdural intracranial hematoma after combined spinal-epidural analgesia in labor.

Intracranial subdural hematoma is a rare, but well-described complication of epidural and spinal anesthesia, as documented by more than a decade of publications. Non-postural headache and vomiting are warning signs. A headache lasting more than 5 days should arouse suspicion of intracranial hemorrhage, whether or not it is associated with the appearance of neurological signs or the deterioration of neurological status. Urgent cranial computed tomography can confirm the diagnosis of subdural hematoma, which has the potential to cause a dramatic cerebral herniation syndrome. A combination of spinal epidural (CSE) anesthesia and analgesia is commonly used to obtain pain relief during caesarean sections and labor. We report the case of a patient who suffered from severe neurological deterioration and manifested signs of brain herniation due to the development of an acute intracranial subdural hematoma after CSE analgesia for labor. An emergency craniotomy was performed to remove the subdural hematoma and the patient recovered well. Close observation of patients undergoing CSE analgesia or anesthesia complaining of prolonged non-postural headaches, with or without neurological symptoms, is recommended.

Extracranial aneurysms of the posterior inferior cerebellar artery. Literature review and report of a new case.

Aneurysms arising from the extracranial portion of the posterior-inferior cerebellar artery (PICA) are considered extremely rare. To date, only ten cases have been reported in the literature. The authors report a case of a 29 year-old male patient admitted comatose in Hunt-Hess grade IV because of an subarachnoid haemorrhage predominantly involving the left cranio-vertebral junction up to C2 rather than the posterior fossa and the fourth ventricle. Angiography showed an extracranial aneurysm at left vertebral artery-PICA junction a few millimetres superior to the dural entry point of the vertebral artery (VA). A left extreme-lateral approach was performed and the aneurysm was successfully clipped. On first year follow-up the patient had completely recovered with no neurological deficits. This paper analyzes the literature review about these rare aneurysms and the technical notes regarding the cranio-vertebral junction approach to these lesions. Factors affecting the neurological outcome of these aneurysms are also reported.

Hemangioblastoma of the filum terminale. Case report and review of the literature.

Hemangioblastomas of the filum terminale are particularly rare tumors. The authors present the case of a 62-year-old woman with a 6 month history of low-back-pain, who underwent surgery for the removal of an hemangioblastoma affecting the cauda at L2-L3 level. This highly vascularized tumour is tightly adherent to the filum terminale and hence is a very challenging pathology to remove. Histologically it consisted in vascular structures interposed to a network of capillary-like vessels, surrounded by stromal cells. MRI, angiography with pre-surgical embolization, and radical surgery represent the focal points in the diagnosis and treatment of these tumours. The most relevant literature has been carefully reviewed.

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.

Post-radiation intramedullary malignant peripheral nerve sheath tumor.

We report the intramedullary growth of a malignant peripheral nerve sheath tumour (MPNST). A 50year-old man developed a severe tetraparesis over a 4-month period. Following irradiation of a chronic tonsillitis during his childhood, the patient had later experienced a number of post-radiation diseases, including a laryngeal cancer that required permanent tracheotomy. Before admission, a magnetic resonance imaging (MRI) study had disclosed a C4-C5 intramedullary lesion. On admission to our Department, the patient had a nearly complete tetraparesis. At surgery, the lesion was exposed through a posterior midline myelotomy. A friable neoplasm, with no clear plane of cleavage, was found. The tumour was subtotally resected. Histological examination, which intraoperatively had not yielded a specific diagnosis, eventually revealed a MPNST, grade intermediate, with ultrastructural and immunohistochemical features consistent with a schwannian differentiation. No postoperative radiotherapy was undertaken. The patient died 9 months later from pneumonial complications. MPNSTs may develop within the spinal cord similarly to their benign schwannian counterpart. The reported sequence of events might support a possible relation between irradiation of the spinal cord and induction, followed by malignant transformation, of intramedullary schwannosis. This unique case must be added to the growing list of radiation-induced spinal cord tumours.

Primary intramedullary primitive neuroectodermal tumor (PNET)--case report and review of the literature.

Spinal primitive neuroectodermal tumors (PNET) are very rare tumors, and intramedullary localization is even less common. Indeed, amongst the 23 cases of the spinal PNET described in the literature, only eight cases had an intramedullary localization. Following the WHO 2000 classification, PNETs have been considered embryonal tumors composed of undifferentiated neuroepithelial cells with a capacity of differentiation into different cellular lines, such as astrocytic, ependymal, melanotic and muscular. They have been considered to arise from a neoplastic transformation of primitive neuroepithelial cells, thereby making their presence possible in any part of the central nervous system. The optimal treatment for these malignant tumors is not yet clear, although, over the years, radiotherapy has been considered the best treatment for spinal PNETs. The described case is that of a 38-year-old man with a primary intra-extramedullary PNET, treated by laminectomy, open biopsy and chemotherapy. The patient, 18 months after the onset of his symptomatology, died without cerebral tumor involvement.

Vasospasm of venous grafts in extra-intracranial by-pass. Report of two cases.

Two patients are described, the first with a giant aneurysm of the left carotid bifurcation previously treated by endovascular technique, the second with a bilateral intracavernous aneurysm: both were submitted to high-flow by-pass operation. The first patient was a 40 year-old woman who had presented subarachnoid hemorrhage 6 months before operation. She had been treated by means of a high-flow by-pass between the external carotid artery and the middle cerebral artery. Control angiograms performed 12 hours later showed a stenosis above the suture between the external carotid artery and the venous graft. Angioplasty was performed by endovascular route: new angiograms showed occlusion of the graft while dopplersonography demonstrated the presence of flow within the graft. Angiograms performed 1 week later showed marked vasospasm of the venous graft, of the internal carotid artery, the anterior cerebral artery and the middle cerebral artery. The evolution of spasm of the graft and of the intracranial arterial flow was monitored by dopplersonography and MR-angiography: the latter was performed 20 days after the last angiography and confirmed patency of the graft, while dopplersonography showed resolution of vasospasm. Finally, the aneurysm was embolized. The second patient was a 49 year-old woman with mild left palpebral ptosis and retro-orbital pain. She had already been submitted to high-flow by-pass operation 7 months earlier to treat a right intracavernous aneurysm; the left by-pass was necessary because the intracavernous aneurysm had become symptomatic. One week after surgery, spasm of the venous graft was documented by MR-angiography. In both cases, treatment consisted of calcium antagonists as well as hypertensive and hypervolemic medication, which was successful in treating vasospasm of the venous graft and its symptoms. Spasm of the venous graft, a well-known occurrence in cardiac revascularization, can also be observed in cerebral revascularization.

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.

Pericranial flap fixation using titanium miniplates and screws.

Opening the frontal sinuses is a common occurrence during neurosurgical procedures involving the anterior cranial base. Obliteration of the exposed sinuses is usually accomplished packing them with various materials and/or covering them with an anteriorly-based pericranial flap. In the absence of more extensive cranial base defects, the flap only needs to be wrapped around the sinus and secured against its posterior wall. We describe the technique for and the results of using titanium miniplates and screws to secure the pericranial flap to the inner surface of the frontal bone. In 10 patients treated with this alternative technique, the pericranial flap provided an excellent separation between the sinuses and the intradural compartment. No cases of cerebrospinal fluid leakage or infections were observed.

Discontinuous myelotomy: an alternative to standard myelotomy in the surgical treatment of intramedullary spinal cord tumours.

BACKGROUND: Myelotomy is an essential step for the removal of intramedullary tumours. Often, this manoeuvre requires division of large vessels surfacing the midline, contributing to the development of postoperative sensory deficits. We developed a technique of discontinuous myelotomy to preserve the integrity of these large spinal cord vessels. METHODS: Over a three-year period, we approached 20 intramedullary astrocytomas through a posterior myelotomy consisting of two separate incisions one above and the other below the midline vessel. The tumour was removed using the Cavitron ultrasound aspirator (CUSA), through either incision. Tumour underlying the bridging area between the two incisions was successfully removed through an oblique view. FINDINGS: We retrospectively analysed the clinical outcome in terms of sensory function. Follow-up examinations showed that up to 70% of the patients had their sensory function unchaged. 5 (20%) patients experienced a permanent worsening of their deficits, involving superficial and deep sensation in cases 1 and 4, respectively. Two (10%) patients showed significant improvement. INTERPRETATION: Discontinuous myelotomy is a viable technical option whenever the presence of large vessels on the median raphe would make the standard midline myelotomy unsafe.

The results of the surgical and conservative treatment of non-neurologic comminuted thoracolumbar fractures.

A retrospective radiologic study of 40 non-neurologic thoracolumbar fractures allowed for the evaluation of the long-term results of surgical and conservative treatment in terms of correction of the post-traumatic deformity. The Magerl classification and the McCormack scale were used to select compressive type fractures (type A), and fractures characterized by comminution of the vertebral body without involvement of the posterior elements. Instability related to comminution and to considerable diastasis of the fragments is at the basis of failure of conservative (plaster brace) and surgical (short posterior fixation and posterolateral fusion) treatments. Severe type A fractures treated conservatively have, in fact, at follow-up shown significant residual deformity, while failure of the instrumentation or loss of correction in 40% of cases treated surgically has been revealed.

Nontraumatic acute spinal subdural hematoma: report of five cases and review of the literature.

Acute subdural spinal hematoma occurs rarely; however, when it does occur, it may have disastrous consequences. The authors assessed the outcome of surgery for this lesion in relation to causative factors and diagnostic imaging (computerized tomography [CT], CT myelography), as well as eventual preservation of the subarachnoid space. The authors reviewed 106 cases of nontraumatic acute subdural spinal hematoma (101 published cases and five of their own) in terms of cause, diagnosis, treatment, and long-term outcome. Fifty-one patients (49%) were men and 55 (51%) were women. In 70% of patients the spinal segment involved was in the lumbar or thoracolumbar spine. In 57 cases (54%) there was a defect in the hemostatic mechanism. Spinal puncture was performed in 50 patients (47%). Late surgical treatment was performed in 59 cases (56%): outcome was good in 25 cases (42%) (in 20 of these patients preoperative neurological evaluation had shown mild deficits or paraparesis, and three patients had presented with subarachnoid hemorrhage [SAH]). The outcome was poor in 34 cases (58%; 23 patients with paraplegia and 11 with SAH). The formation of nontraumatic acute spinal subdural hematomas may result from coagulation abnormalities and iatrogenic causes such as spinal puncture. Their effect on the spinal cord and/or nerve roots may be limited to a mere compressive mechanism when the subarachnoid space is preserved and the hematoma is confined between the dura and the arachnoid. It seems likely that the theory regarding the opening of the dural compartment, verified at the cerebral level, is applicable to the spinal level too. Early surgical treatment is always indicated when the patient's neurological status progressively deteriorates. The best results can be obtained in patients who do not experience SAH. In a few selected patients in whom neurological impairment is minimal, conservative treatment is possible.

Surgical treatment of penetrating orbito-cranial injuries. Case report.

Penetrating orbital injuries are not frequent but neither are they rare. The various diagnostic and therapeutic problems are related to the nature of the penetrating object, its velocity, shape and size as well as the possibility that it may be partially or wholly retained within the orbit. The authors present another case with unusual characteristics and discuss the strategies available for the best possible treatment of this traumatic pathology in the light of the published data. The patient in this case was a young man involved in a road accident who presented orbito-cerebral penetration caused by a metal rod with a protective plastic cap. Following the accident, the plastic cap (2.5x2 cm) was partially retained in the orbit. At initial clinical examination, damage appeared to be exclusively ophthalmological. Subsequent CT scan demonstrated the degree of intracerebral involvement. The damaged cerebral tissue was removed together with bone fragments via a bifrontal craniotomy, the foreign body was extracted and the dura repaired. Postoperative recovery was normal and there were no neuro-ophthalmological deficits at long-term clinical assessment. Orbito-cranial penetration, which is generally associated with violent injuries caused by high-velocity missiles, may not be suspected in traumas produced by low-velocity objects. Diagnostic orientation largely depends on precise knowledge of the traumatic event and the object responsible. When penetration is suspected and/or the object responsible is inadequately identified, a CT scan is indicated. The type of procedure to adopt for extraction, depends on the size and nature of the retained object. Although the possibility of non-surgical extraction has been described, surgical removal is the safest form of treatment in cases with extensive laceration and brain contusion.

Metastatic spinal cord compression. Clinical remarks.

BACKGROUND: Metastatic compression of the spinal cord is a frequent occurrence throughout the evolution of neoplastic disease. Possible clinical-diagnostic strategies and therapeutic management of this pathology are discussed in terms of survival and quality of life. METHODS: The study includes 59 patients (40 males and 19 females, with an average age of 48.4 years) with metastatic spinal compression treated surgically in our centre (in some cases with stabilization of the spinal segment involved). RESULTS: In 40 cases the localization of the primary tumor was known when the patient was admitted. The segment involved was the dorsal one in 41 cases. The most frequent type of tumor was pulmonary carcinoma in males and breast carcinoma in females. Average survival was 5.3 months. Treatment integrated by stabilization improved the quality of life in comparison to laminectomy alone. Survival was also influenced by the histological type and site of the primary tumor. CONCLUSIONS: Surgical treatment not only prolongs survival but, above-all, guarantees a satisfactory quality of life.

A carbon fiber reinforced polymer cage for vertebral body replacement: technical note.

OBJECTIVE: We analyzed the surgical technique used for the replacement of damaged vertebral bodies of the thoracolumbar spine and the carbon fiber reinforced polymer (CFRP) cages that are used to replace the pathological vertebral bodies. We also evaluated the biomechanical properties of carbon composite materials used in spinal surgery. TECHNIQUE: The surgical technique of CFRP implants may be divided into two distinct steps, i.e., assembling the components that will replace the pathological vertebral bodies and connecting the cage to an osteosynthetic system to immobilize the cage. INSTRUMENTATION: The CFRP cages, made of Ultrapek polymer and AS-4 pyrolytic carbon fiber (AcroMed, Rotterdam, The Netherlands), are of different sizes and may be placed one on top of the other and fixed together with a titanium rod. These components are hollow to allow fragments of bone to be pressed manually into them and present threaded holes at 15, 30, and 90 degrees on the external surface, permitting the insertion of screws to connect the cage to an anterior or posterior osteosynthetic system. RESULTS: To date, we have used CFRP cages in 13 patients undergoing corporectomies and 10 patients undergoing spondylectomies. None of our patients have reported complications. CONCLUSIONS: CFRP implants offer several advantages compared with titanium or surgical grade stainless steel implants, demonstrating high versatility and outstanding biological and mechanical properties. Furthermore, CFRP implants are radiolucent and do not hinder radiographic evaluation of bone fusion, allowing for better follow-up studies.