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.

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.

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.

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.

A new type of prehensile suction device.

The authors describe a new suction device with prehensile properties that has proved itself particularly useful in the removal of certain types of tumor, especially extramedullary.

Orbital schwannomas: report of nine cases and review of the literature.

The authors report 9 cases of orbital schwannoma out of a total of 148 orbital tumors operated. The computed tomography (CT) scan is considered superior to other methods used in the radiological work-up of endoorbital tumors because, in addition to being noninvasive, it gives direct visualization of the lesion and more precise localization both with respect to the muscular cone and tridimensionally. Unfortunately, preoperative diagnosis is not always possible solely on the basis of the CT scan because the enhancement of the tumor is not constant, thus making differential diagnosis with meningioma and cavernous angioma problematic. In addition, CT enables the surgeon to choose the best route for tumor removal. Operative results are good and are influenced by the use of microsurgical techniques.

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.

Lumbar disc hernia secondary to gunshot injury.

The authors present a case of injury to the 4th lumbar root secondary to a gunshot wound. The lesion was not directly related to the traumatic action of the projectile, but was caused by the compressive action of disc material forced into the vertebral canal as a result of the destructive effects of a 7.65 caliber bullet.

Intradural lumbar disc hernia: description of three cases.

Three new cases of intradural lumbar disc hernia are added to the 25 previously published cases. The clinical features of the lesion, which usually occurs at the level of the cauda equina, and its pathogenesis are discussed.

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.

Surgical strategies in the treatment of symptomatic osteomas of the orbital walls.

We present a series of 19 surgically treated osteomas involving the orbital walls. Eight were localized at the junction of the frontal sinus and orbital roof, three were frontoethmoidal, two were of the orbital roof, one of the lateral wall, one of the orbital floor, and four involved all the walls of the orbit and were termed panorbital. All tumors at the junction of the frontal sinus and the orbital roof as well as those originating from the orbital roof proper were removed by frontal craniotomy. In the three that were frontoethmoidal, osteotomies were performed. Lateral and inferior orbitotomies were done when the corresponding orbital walls were affected. The four panorbital osteomas required large frontotemporal craniotomies in association with superolateral orbitotomy and zygomatic and/or malar osteotomy, when necessary. Satisfactory cosmetic and functional results were obtained in all but two cases of panorbital osteomas, in which the neurological deficit worsened after surgery. We discuss the choice of the various approaches described, with reference to the relevant literature.

Meningiomas of Meckel's cave.

A series of 16 patients with meningiomas of Meckel's cave is reported. Trigeminal neuralgia, typical or atypical, was the initial symptom in 10 patients (62.5%). At admission, trigeminal signs and symptoms were present in 15 patients (93.7%); in 7 patients (43.7%), trigeminal dysfunction was combined with the impairment of other cranial nerves. On retrospective analysis, these patients fall into two clinical groups that differ also in prognosis. Group 1 comprises eight patients with trigeminal signs and symptoms only. These patients had small meningiomas strictly affecting Meckel's cave. Total removal of the tumor was achieved in seven of eight patients, without adjunctive postoperative neurological deficits. In this group, there were no tumor recurrences. Group 2 comprises the other eight patients in whom trigeminal dysfunction was combined with impairment of other cranial nerves. These patients had large tumors arising from Meckel's cave and secondarily invading the cavernous sinus (five patients) or extending into the posterior fossa (two patients) or largely growing into the middle fossa (one patient). Total removal was achieved in only one patient, and a worsening of the preoperative neurological status was observed in four patients; there were three cases of tumor progression. A subtemporal intradural approach (used in the past in every case) is still used for the small tumors of Group 1 with good results. Since 1985, for tumors involving the cavernous sinus, we have employed a frontotemporal craniotomy with extradural clinoidectomy and superior and lateral approach to the cavernous sinus. When the tumor extends toward the posterior fossa, we use a combined temporosuboccipital-transpetrosal approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Spinal glioblastomas: report of seven cases and review of the literature.

Intramedullary glioblastomas are uncommon tumors. They occur chiefly in the cervicothoracic segments, have a slight tendency to occur in the early decades of life, and have a short clinical history before diagnosis. We report seven cases and discuss the salient features of these tumors, particularly the pathological features and treatment, in light of the relevant literature.

Tentorial meningiomas: surgical experience with 61 cases and long-term results.

The authors report their experience and long-term results in the surgical treatment of 61 tentorial meningiomas. These cases were operated on between 1951 and 1985 and represented 4.8% of all intracranial meningiomas operated on in that period. The mean duration of clinical history was 29 months, except for cases of meningioma of the posteromedial border, for which it was 5 years. Plain x-ray films and cerebral angiograms were obtained in all cases. Computerized tomography, performed in the last 20 cases (32.7%), supplied much better lesion topography and early diagnosis. The tumor site was posterolateral in 26 cases (42.6%), anterolateral in 14 (22.9%), posteromedial in eight (13.1%), at the free border in seven (11.4%), and in the tentorium itself in six (9.8%). Lateral and medial tumors with solely or mainly supratentorial development were approached from above. The approach from below was reserved for meningiomas with subtentorial involvement only. In meningiomas with both supra- and subtentorial growth, a supratentorial bone flap was combined with a suboccipital craniectomy using a retromastoid incision. The mortality rate was 9.8%. Of the remaining 42 patients, who were followed for at least 5 years, long-term results were good in 26 cases (61.9%), fair in 11 (26.2%), and poor in five (11.9%). Postoperative complications arose in 34% of the patients, but cleared in 27%.

New steel device for occipitocervical fixation. Technical note.

A new steel device for occipitocervical fixation is described. The system is easily and quickly applied, and affords a stronger and more secure means of attachment of the steel wires than using the occipital bone alone.

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.

A two-step supraorbital approach to lesions of the orbital apex. Technical note.

A two-step supraorbital approach to lesions of the orbital apex is described. This technique is easy and allows a satisfactory exposure of the region. In addition, the reconstruction resulting from the procedure is anatomically perfect. The authors report the operative results obtained in 20 patients and compare this two-step supraorbital procedure with similar surgical techniques described previously.