Osteoid osteoma of the cervical spine: surgical treatment or percutaneous radiofrequency coagulation?

Osteoid osteoma (OO) of the cervical spine is frequently located close to the vertebral artery, spinal cord, or nerve roots and complete surgical excision is sometimes difficult by a limited approach and more extended surgery can require spinal fusion. Percutaneous radiofrequency coagulation (PRC) has demonstrated efficacy in the treatment of OO of the pelvis and limbs however, its role in the cervical spine is still nuclear. The Authors present a series of nine cases of OO of the cervical spine, six treated with surgical excision and three with PRC. No neurological or vascular complications occurred in both series. One case of the surgical series had only partial relief of persistent pain for 1 year due to incomplete excision, but is doing well 4 years after surgery. All the other surgical cases had complete relief of symptoms immediately after surgery and are symptom-free 3-10 years later. Two cases of PRC had complete relief of symptoms 24-48 h after surgery and are symptom-free 2 and 3 years later. One case of recurrent OO after surgery and treated with PRC with a reduced dose improved only, and still requires anti-inflammatory drugs 2 years after the procedure. Our still limited experience suggests that PRC can be safely performed in local anaesthesia with the patient awake, enabling to check for signs and symptoms of possible neurological injury. PRC can substitute extensive posterior approaches and reconstructions for OO of the posterior arch and joint pillar.

A randomized phase III study: comparison between intravenous and intraarterial ACNU administration in newly diagnosed primary glioblastomas.

BACKGROUND: In this randomized phase III study, the effectiveness as well as the side-effects of intraarterial [i.a.] (17 patients) versus intravenous [i.v.] (16 patients) ACNU [Nimustine] administration in newly diagnosed glioblastoma, were compared. PATIENTS AND METHODS: All patients undenwent extensive surgical resection, and both groups were homogeneous for the other known risk factors. Thirty-three patients with glioblastoma were treated with ACNU at the dose of 80-100 mg/m2. Treatment was repeated every 5-8 weeks for a minimum of 2 and maximum of 14 cycles. Total survival time (TST) and to time to progression were chosen as outcome variables. RESULTS AND CONCLUSION: No significant differences in systemic and hematological toxicity between the i.a. and iv. ACNU administration routes were detected. In both groups, tolerance of the procedure was excellent. Analysis of the main outcome measured showed no significant differences between i.a. and i.v. ACNU administration: time to progression was 6 months for i.a. ACNU and 4 months for i.v. ACNU and total survival time was 17 months for i.a. ACNU and 20 months for i.v. ACNU. In spite of ACNU dose incrementation, obtained through i.a. route administration, and subsequent higher concentration in the tumor bed, no improvement could be achieved in effectiveness.

MRI and brainstem auditory evoked potential evidence of eighth cranial nerve involvement in multiple sclerosis.

An MS patient experienced sudden hearing loss. Brainstem auditory evoked potentials, previously normal, showed substantial abnormalities that suggested the impairment of the distal part of the acoustic nerve. MRI detected a small hyperintense lesion along the acoustic nerve; the lesion decreased in size and then disappeared after steroid treatment. This demonstrates that a demyelinating lesion in the distal tract of the eighth cranial nerve may cause an acute hearing loss in MS.

Cognitive potentials: ipsilateral corticocortical interconnections in prefrontal human cortex ablations.

The research deals with the possible role of the essentially monosynaptic bidirectional corticocortical connections between occipito-temporo-parietal association cortical areas and frontal areas in the genesis of some contingent negative variation (CNV) components, especially on the supramodal dorsolateral prefrontal regions. With standard and topographic mapping methods of analysis, the multicomponent CNV complex formation was examined in 7 patients with extensive frontal cortex ablations exactly identified through CT/MRI examinations, and in 10 normal subjects. On the scalp over the ablated frontocortical areas, no consistent post-warning auditory N100 a-b-c, P200, P300, early and late CNV components were recordable. The hypothesis is proposed that the bidirectional ipsilateral long-distance pathways which interconnect uni-polymodal occipito-temporo-parietal cortical areas to prefrontal ones, in particular the arcuate-superior longitudinal and superior/inferior occipito-frontal fasciculi, play an important role in the genesis of several CNV complex components, especially the multicomponent post-S1 auditory N100. The posteroanterior sequential latency differences of these neurocognitive components, roughly measured along the scalp or on MRI imagings, is probably accounted for by the transcortical ipsilateral conduction time of about 1 cm/ms (10 m/s).

Transsynaptic degeneration of lateral geniculate bodies in blind children: in vivo MR demonstration.

PURPOSE: To investigate signal alterations in the thalamic lateral geniculate bodies of blind patients compatible with transsynaptic degeneration of these nuclei caused by pregeniculate or postgeniculate interruption of the visual pathway. METHODS: Six patients were selected from a group of blind children in our care. Four had cerebral palsy caused by periventricular leukomalacia, one had infantile neuroaxonal dystrophy, and one had Chiari I malformation and hydrocephalus, which was worsened by bilateral ischemic lesions of the occipital lobes. MR examinations (obtained at 0.5 T) were reviewed retrospectively by two neuroradiologists, with particular attention to the visual pathway. RESULTS: Symmetric, focal areas of T2 prolongation were found at the precise site of the lateral geniculate bodies. CONCLUSION: Anterograde (pregeniculate) and retrograde (postgeniculate) transsynaptic degeneration of the second neurons of the visual pathway produce alterations in MR signal.

Ganglioneuroblastoma of the spinal cord.

We report a case of ganglioneuroblastoma of the spinal cord in a 42-year-old man. MR examination was nonspecific, and the diagnosis was made from histologic findings. The MR picture was that of an intramedullary, mainly solid tumor with a central necrotic or cystic portion. The clinical picture and course were also nonspecific.

Cerebral visual impairment in periventricular leukomalacia: MR correlation.

PURPOSE: To evaluate the involvement of central visual pathways in cases of periventricular leukomalacia, and to correlate the neuroradiologic findings with the degree of visual acuity. METHODS: The MR brain examinations of 27 preterm children affected by cerebral palsy resulting from periventricular leukomalacia and without significant ophthalmologic lesions were reviewed retrospectively to search for possible involvement of the optic radiations and/or of the calcarine cortex. The data were compared with the degree of visual acuity estimated by means of the Teller Acuity Cards test. RESULTS: Seventeen (63%) of the 27 patients had cerebral visual impairment, which correlated strongly with MR lesions. Quantitative reduction and signal hyperintensity of the peritrigonal white matter and atrophy of the calcarine cortex were present in the more severe cases. In two blind patients, an altered MR signal was detected in the lateral geniculate bodies. CONCLUSION: This study clearly establishes a relationship between specific MR findings and visual impairment in children with periventricular leukomalacia. The finding of hyperintensity in the lateral geniculate bodies was interpreted as an axonal reaction. MR imaging is useful for detecting potential visual impairment and for improving clinical diagnosis.

Vasomotor response to CO2 and L-Arginine in patients with severe internal carotid artery stenosis; pre- and post-surgical evaluation with transcranial Doppler.

BACKGROUND AND AIM: Carotid artery disease may cause both thromboembolism and cerebral blood flow disturbances, particularly in subjects with impaired hemodynamic compensatory mechanisms. The aim of this study was to evaluate by transcranial Doppler (TCD) the hemodynamic changes induced by CO2 and L-Arginine stimulation in a selected population with severe unilateral carotid stenosis (70-80%), before and after carotid endarterectomy, in order to determine the effect of surgery in the vascular hemodynamics of these patients. METHODS: We studied 20 subjects (mean age 66.4 years) consecutively admitted to our institute with ischemia and unilateral severe internal carotid artery stenosis (70-80%) detected by Color Doppler. All patients underwent arterial digital subtraction angiography to confirm the ultrasonographic evaluation. TCD was performed bilaterally; blood flow velocity was monitored during CO2 and L-Arginine stimulation both in basal conditions and three months after surgery. RESULTS: After endarterectomy, mean velocity increased in response to both stimuli with a trend toward statistical significance. A significantly lower reactivity to L-Arginine on the stenotic side was found in the pre-operative phase: this asymmetrical reactivity was no longer observable after carotid endarterectomy. CONCLUSIONS: We found a statistically significant difference in L-Arginine reactivity in the stenotic side of patients with severe unilateral internal carotid stenosis. This is probably related to an alteration of the endothelium function due to the carotid pathology, since the abnormalities disappeared three months after endarterectomy.

The effects on auditory neurocognitive evoked responses and contingent negative variation activity of frontal cortex lesions or ablations in man: three new case studies.

Our previous research in patients with extensive surgical ablations of the prefrontal cortex contradict the hypothesis of some authors that the generators of several auditory event-related potentials (ERPs) (N100; P200; N200; P300; SW), recordable in humans with depth/scalp electrodes and MEG over the prefrontal dorsolateral cortical areas, are essentially located in medial prefrontal and anterior cingulate-limbic cortices. Using a standard CNV paradigm, 21 EEG electrodes and topographic mapping analysis, the post-warning (S1) auditory N100a b c, P200, P300 (binaural clicks) and CNV activity were recorded in three additional patients after extensive dorsolateral and/or medial prefrontal cortex ablations, verified through CT/MRI examinations. No true post-S1/CNV components were recordable over the ablated frontal areas, only sporadic volume-conducted ERPs probably generated in the temporo-parietal lobes or posterior cingulate gyrus. For one of these patients, after excision of a vast right frontal epileptogenic cortical region (including extensive dorsolateral areas, but sparing the fronto-medial cortex and anterior/middle cingulate gyrus), no post-S1/CNV components were recordable over the ablated regions. These latest observations again indicate that independent neuronal generators of several post-S1 auditory and CNV components are located in the dorsolateral supramodal premotor/prefrontal cortical areas which are directly, ipsilaterally connected to the uni/multimodal temporo-parieto-occipital sensory and associative regions through the long, two-way, fairly superficial, superior arcuate-longitudinal and deeper superior and inferior occipito-frontal bundles. Clear and almost constant differences in the latency of some post-S1 N100 subcomponents (especially the time-lapses between onset and the highest amplitude of the N100 a and c) over various posterior, central and anterior cortical areas sequentially involved, roughly measured in 10 normal subjects along the scalp and with MRI cerebral imaging, may probably be accounted for by the transcortical homohemispheric conduction time, which varies in our scalp recordings from 1 cm/0.74-1.28 ms, mean approximately 1 cm/1.02 ms ( approximately 9.8 ms).

Anterior extraoral surgery to the upper cervical spine.

STUDY DESIGN: A series of 10 patients surgically treated with prevascular or retrovascular extraoral retropharyngeal approach to the upper cervical spine is examined. OBJECTIVES: In orthopedic surgery, retropharyngeal approach may replace the transoral surgery, obviating the risks of infection and the uncomfortable postoperative course of cases in which median labiomandibular glossotomy was used to accomplish complex bone reconstruction. SUMMARY OF THE BACKGROUND DATA: The transoral approach is reported in literature as the classical anterior access to the upper cervical spine that provides direct exposure for anterior decompression of the spinal cord. The risks, the surgical limits, and the postoperative difficulties of transmucosal access suggest the use of an anterior extraoral retropharyngeal approach in orthopedic surgery. METHODS: The series includes four neoplastic lesions (osteoma, aneurismal bone cyst, giant cell tumor, solitary metastasis), three retropharyngeal ossifications resulting from diffuse idiopathic skeletal hyperostosis, and a single case of os odontoideum, craniocervical malformation, and postlaminectomy kyphosis. RESULTS: At follow-up evaluation, all patients achieved a satisfactory outcome, with good clinical and radiographic results; nasotracheal intubation obviated the need for tracheostomy. The wide surgical exposure allowed reconstruction with iliac strut bone grafts and internal fixation in six patients, avoiding the need of a halo device. The only complications were four instances of transient palsies of the marginal mandibular branch of the facial nerve. CONCLUSIONS: In the anterior surgery of the upper cervical spine, the prevascular approach allows a wide surgical exposure, with visualization similar to that obtained with median labiomandibular glossotomy. The retrovascular approach is indicated in selected cases, such as tumor adjacent to the vertebral artery and C1-C2 arthrodesis with bilateral transarticular screws according to Barbour.

Neurinoma of the trigeminal root and atypical trigeminal neuralgia: case report and review of the literature.

BACKGROUND: Neurinomas of the trigeminal nerve are a rare entity: those located in the posterior fossa account for 20% of all cases. In the majority of cases, the clinical presentation begins with fifth cranial nerve involvement producing a constant pain associated with other cranial nerve palsy and cerebellar signs. METHODS: We report the clinical features, neuroradiological imagings, and management of a case of trigeminal neurinoma located in the cerebellopontine angle, arising from the Vth cranial nerve root, presenting with an atypical trigeminal neuralgia; moreover, we analyze similar cases reported in the literature and we discuss whether pain can be produced by a neurinoma that arises central to the ganglion. RESULTS: The tumor presented with an atypical trigeminal neuralgia characterized by constant trigeminal pain with paroxystical burns, hyperesthesia and hyperactive autonomic dysfunction. Neuroradiological examinations provided the best preoperative localization of this lesion, allowing better planning of the surgical approach, considering the large size of this tumor. A retromastoid incision and posterior fossa craniectomy approach was used, with complete excision of the tumor. The paraxysmal sharp pain and hyperesthesia disappeared completely, but the constant burning pain persisted although it was less intense. At an 8-month follow-up examination, the patient showed a progressive improvement of clinical symptoms and control magnetic resonance imaging (MRI) showed the complete removal of the neoplasm and the absence of residuals or recurrences. CONCLUSION: Although in a high percentage of cases of atypical trigeminal neuralgia a neurovascular conflict might be suspected, the review of the present case suggests that the hypothesis of a trigeminal neurinoma must be investigated both with adequate neuroradiological procedures and/or microsurgical exploration of the trigeminal root.

Primary solitary intracranial melanoma: case report and review of the literature.

Among CNS tumors, intracranial melanomas represent a subject of interest for neurooncologists and neurosurgeons because clinical and radiological patterns of these tumors can mimic the presence of meningiomas, and in spite of their malignant behavior they can be satisfactorily treated. In the present report we describe a new case of primary intracranial melanoma that displayed some radiological features of meningioma; we review the clinical features of 80 previously well-documented cases. The importance of neuroradiological and histochemical (S-100 protein, antimelanin antibodies, proliferating cell nuclear antigen staining) methods and of flow cytometry in helping with histopathological examination is stressed. Review of the clinical histories demonstrates that surgical excision is recommended in most cases, depending on tumor location, and that if total removal is performed, long-term disease-free periods can be attained.

Internal carotid occlusion associated with migraine syndrome: a case study of a 22-year-old female.

Migraine and migraine-like headaches are sometimes associated with acquired types of carotid artery disease. We examined a 22-year-old female suffering from periodic migraine, sometimes with "atypical" features. Color Flow Duplex Sonography revealed an occlusion of the right internal carotid artery (ICA) and a possible severe stenosis of the cervical segment of the left ICA. Digital Subtraction Angiography combined with Angio-Magnetic Resonance Imaging and Echographic Imaging suggested the possibility of a fibromuscular dysplasia involving both ICAs. It is suggested that some atypical features of headache could represent symptoms of a carotid pathology.

Disseminated intravascular coagulation during total hip replacement.

Disseminated intravascular coagulation (DIC) is an extremely serious hemorrhagic disorder and one that is potentially lethal. DIC is more frequently observed as a complication of obstetric pathologies, diffused neoplasms, bacterial sepsis, blood transfusions, traumas and adipose embolias. The literature reports very few cases occurring after total hip replacement, two of which the cause of death. In all of the cases described one or boh prosthetic components are cemented. The authors report a case observed after total hip replacement in a patient submitted one year previously to contralateral hip replacement. Severe hypotension, bradychardia and profuse bleeding of the wound and from the drainages one hour after suturing constituted the initial symptom. Recognition of the clinical findings, after exclusion of a iatrogenic lesion, and subsequent treatment in intensive therapy allowed us to save the patient. The syndrome must be suspected and immediately diagnosed when profuse bleeding that cannot be related to vascular lesion is observed immediately postsurgery after cemented or hybrid hip replacement. Confirmation through hematological tests and timely treatment in a specialized center are indispensable requirements to save the life of the patient.

Fracture of the ceramic epiphysis in hip arthroplasty.

Between November 1985 and October 1993, a total of 694 ceramic-ceramic hip arthroplasties were implanted; up until 1987 the alumina used in the first 82 cases was Ostalox, produced by IMEC of Caravaggio, characterized by poor control of the size of the crystals; after 1987 Biolox alumina of the Feldmhule company was used in 612 cases. Fracture of the ceramic head occurred in 2 cases; in both patients ceramic was of the Ostalox type, meaning a 2.4% incidence of fracture; up until the present none of the 612 Biolox heads has presented this complication.

Intralesional surgery of primary tumors of the anterior cervical column.

The study involves a series of 10 primary neoplasms of the anterior cervical column (body and transverse processes) surgically treated by intralesional excision and followed-up after 2-10 years. The series included 6 benign and 4 malignant neoplasms. Among the benign tumors 4 cases were classified Enneking stage II (2 osteoid osteomas, 1 fibrous dysplasia, 1 osteoma): after simple excision none of the cases revealed symptoms or signs of recurrence at long-term follow-up. The other 2 benign forms were stage III (giant cell tumor and aneurysmal cyst): both of the cases were treated by extracapsular intralesional excision after selective arterial embolization and reconstruction with anterior fusion; the giant cell tumor was irradiated after surgery: at long-term follow-up the patients were asymptomatic and there were no signs of recurrence. The 4 malignant neoplasms (stage IIB) were 1 osteosarcoma and 3 solitary plasmacytomas with spinal cord compression. The osteosarcoma was treated by intralesional excision in 3 stages and radiation therapy, and there were no signs of disease 6 years after diagnosis. The cases of plasmocytoma were treated by intralesional excision and spinal cord decompression, anterior fusion with iliac graft and plate, radiation therapy, and chemotherapy, and they died after 2, 3 and 4 years with findings of multiple myeloma with no signs of disease at the level of the cervical vertebra treated.

Cyst of the medial meniscus: observation of two cases.

The authors report two cases of cyst of the medial meniscus. In both cases imaging diagnostics, CT scan, or MRI allowed us to reveal the characteristic horizontal meniscal lesion that would be the primary cause of cystic degeneration of the meniscus. The two cases were treated by selective resection of the meniscal lesion and arthroscopic decompression of the cyst.

Hydroxyapatite as metallic prosthesis coating: preliminary clinical experience.

The authors report the radiographic results of 65 An. C.A. prosthetic stems coated with hydroxyapatite and followed-up at least 24 months after implantation. A comparison with a homogeneous group of aluminum-coated An.C.A. stems showed that hydroxyapatite-coated stems are characterized by better osteointegration, with a clearly inferior incidence of radiolucent lines at the bone/prosthesis interface. Macroscopic observation and histologic examination carried out on two stems removed because of persistent pain to the thigh revealed partial resorption and fragmentation of the coating. The authors believe that this phenomenon, the object of other observations reported in the literature, may indicate the reduced stability of the coating in the long run, and as such further in-depth study is required.

The use of ceramic in prosthetic hip surgery. The state of the art.

The authors review current knowledge regarding the use of ceramic materials in prosthetic hip surgery, both as constituents of prosthetic components, and as materials used to coat metallic surfaces. A review of the literature defines the advantages and disadvantages to using ceramic-polyethylene or ceramic-ceramic combinations, based on the possibility that alumina coating may favor localized bone demineralization, and on the first promising clinical results of the use of hydroxyapatite coating.

Lateral retrovascular approach to the upper cervical spine.

The authors describe the surgical anatomy of lateral approach to the upper cervical spine. The approach is retrovascular retropharyngeal extraoral allowing for anterolateral exposure of the upper cervical column, and it may be enlarged posteriorly on the homolateral posterior hemiarch of C1 and C2, and/or inferiorly on the lower cervical column. Absolute indications to this approach are anterolateral fusion with transarticular screws C1-C2 and excision of skeletal neoplasms adjacent to the vertebral artery. For other indications such as the treatment of anterior neoplasms and spinal cord decompression it is preferable to use pre-vascular extraoral approach or transoral approach.