Biomedical subjects

Bernard George

Publications and source records attributed to Bernard George.

11 recordsLinked to original sources

PubMed2006

Microsurgical cervical nerve root decompression by anterolateral approach.

OBJECTIVE: Cervical radiculopathy caused by a posterolateral soft disc herniation or spondylosis is a common pathology. METHODS: Decompression of a stressed cervical nerve root is a routine neurosurgical procedure. Most of the time it is achieved through an anterior approach and, less frequently, through a posterior approach in specific indications. RESULTS: According to the principles that an anterolateral compression must directly be reached and that working in the vicinity of the vertebral artery is safe under visual control, we developed the anterolateral approach to the cervical intervertebral foramen and the nerve root using a minimally invasive technique to remove the offending process. CONCLUSION: Microsurgical cervical nerve root decompression by anterolateral approach is a minimally invasive technique, permitting one to remove the offending process staightforwardly. The disc and bone resections are minimal. This method avoids osteoarthrodesis or arthroplasty with disc prosthesis. This technique is efficient with good results and low morbidity.

Cervical Vertebrae↗

PubMed2006

Antero-lateral approach to the V3 segment of the vertebral artery.

OBJECTIVE: We describe our surgical technique of exposure, control, and transposition of the third segment of the vertebral artery (VA V3 segment). METHODS: The VA V3 segment extends from the C2 transverse foramen to the dura mater of the foramen magnum. It initially courses vertically between the C2 and C1 transverse foramens, then runs horizontally over the atlas groove, and finally obliquely upwards before piercing the dura mater. Exposure of the VA V3 segment through an antero-lateral approach is performed by passing medially to the sternomastoid muscle. After exposure and protection of the spinal accessory nerve, the C1 transverse process is identified below and in front of the mastoid tip. The small muscles that insert on it are cut to expose the C1-C2 portion. The inferior aspect of the horizontal portion is safely separated from the atlas groove by elevating the subperiosteal plane and the superior aspect is freed by a cut a few millimeters above the VA on the occipital condyle. Complete unroofing of the C1 transverse foramen is achieved by resecting the bone while leaving intact the subperiosteal plane. The VA then can be transposed. Venous bleedings during the dissection from periosteal sheath tearing can be controlled by direct bipolar coagulation. RESULTS: The control of the VA V3 segment is essentially used for lesions in the VA vicinity and to improve the surgical exposure at the craniocervical junction level. Indications therefore are tumoral removal, VA decompression, and rarely, nowadays, VA revascularization. CONCLUSION: Perfect knowledge of the anatomy and the surgical technique permits a safe exposure, control, and transposition of the VA V3 segment. This is the first step of many surgical procedures.

Cerebral Arteries↗

PubMed2006

Anterolateral approach to the V1 segment of the vertebral artery.

OBJECTIVE: We describe the normal anatomy, variations, and the surgical technique to expose and control the V1 segment of the vertebral artery (VA). METHODS: The VA V1 segment extends classically from the subclavian artery to the C6 transverse foramen. It courses obliquely upwards and posteriorly in the cervical fat tissue, at a distance of 5 to 10 mm from the C7 vertebral body. Along its course, the VA V1 segment is crossed by the inferior thyroid artery, the thoracic duct, and the sympathetic chain. For neurosurgeons, the safest approach is to expose the distal part of the V1 segment at the C6 transverse foramen level through an antero-lateral approach. Otherwise, direct exposure of the subclavian artery requires vascular surgery expertise. RESULTS: Surgical exposure of the VA V1 segment can be indicated on approaching the C6-C7 intervertebral disc space for degenerative disease or on treating tumoral processes in its vicinity. With developments of endovascular techniques, revascularization procedures are more rarely indicated nowadays. CONCLUSION: Perfect knowledge of the anatomy and of the surgical technique permits a safe exposure and control of the VA V1 segment.

Anatomy, Artistic↗

PubMed2006

Anatomical variations of the V2 segment of the vertebral artery.

OBJECTIVE: Our goal was to evaluate the incidence of anatomic variations of the V2 segment (from its entrance into the transverse canal to C2) of the vertebral artery. Ignoring such variations during anterior or lateral approach to the cervical spine can lead to inadvertent injury and potentially serious complications. METHODS: We studied the course of 500 vertebral arteries on 200 magnetic resonance imaging and 50 contrast-enhanced computed tomographic scans. RESULTS: The vertebral artery entered the C6 transverse foramen in 93.0% of all specimens. An abnormal level of entrance was observed in 7.0% of specimens (35 courses), with a level of entrance into the C3, C4, C5, or C7 transverse foramen, respectively, in 0.2% (n = 1; 2.9% of all anomalies), 1.0% (n = 5; 14.3% of all anomalies), 5.0% (n = 25; 71.4% of all anomalies), and 0.8% (n = 4; 11.4% of all anomalies) of all specimens. Seventeen (48.6%) abnormalities were right-sided and 18 (51.4%) were left-sided. Thirty-one out of 250 patients (12.4%) had a unilateral anomaly and two had a bilateral anomaly (0.8%). In cases of abnormal entrance into the transverse foramen on computed tomographic images (n = 6), the area of the unfilled transverse foramens was significantly smaller than the contralateral filled foramen (P < 0.0001) and was significantly smaller than the filled foramen of all patients at the same level (P < 0.0001). In five patients (2.0%), the vertebral artery formed a medial loop either into an unusually large transverse foramen whose internal border was medial to the uncovertebral joint or into the intervertebral foramen. CONCLUSION: The incidence of anatomic variations of the vertebral artery V2 segment is high. Potentially dangerous conditions can be detected on preoperative imaging.

Anthropometry↗

PubMed2005

Osteoid osteomas and osteoblastomas of the occipitocervical junction.

STUDY DESIGN: We describe our surgical experience to remove osteoid osteomas and osteoblastomas of the occipitocervical junction. In this location, vertebral artery vicinity requires special consideration. OBJECTIVES: We illustrate our surgical approaches to remove lesions confidently, while minimizing bone resection to preserve stability. SUMMARY OF BACKGROUND DATA: Up until now, osteoid osteomas and osteoblastomas of the occipitocervical junction are reported as case reports. Several treatment methods have been described to treat osteoid osteomas. Nevertheless, surgery is the treatment of choice for lesions located in the C0-C2 region. METHODS: A retrospective review of 7 patients, including 5 men and 2 women, with a mean age of 21.0 years (range 3.0-38.0) was conducted. Clinical outcomes were evaluated immediately and after a mean follow-up of 27.6 months. RESULTS: There were 6 and 1 patients who underwent surgery with the anterolateral and posterolateral approaches, respectively. In osteoid osteomas, the nidus was removed, and the peripheral condensation was drilled up to normal bone (n = 4) or partially resected (n = 2). One osteoblastoma was removed extensively up to soft tissues. No osteo-arthrodesis was performed. Before surgery, all patients complained of pain, 3 presented with neck stiffness, and 2 with a torticollis. Immediately after surgery, all complaints disappeared. One patient underwent repeat surgery 15 months later for a recurrence. At the end of the follow-up, all patients were symptom-free, and partially resected peripheral condensations were stable on computerized tomography. CONCLUSIONS: Removal of osteoid osteomas and osteoblastomas of the occipitocervical junction is safe and efficient. Stability is preserved if more than half the joints are preserved with a proper surgical approach that minimizes bone resection.

Adolescent↗

PubMed2005

Anterolateral approach to the V2 segment of the vertebral artery.

OBJECTIVE: We describe our surgical technique of exposure and control of the second segment of the vertebral artery (VA V2 segment). Our basic principle is that working in the VA vicinity is more confident under visual control. METHODS: The VA V2 segment extends classically in and between the transverse processes from C6 to C2. This segment can be exposed through an anterolateral approach, passing medially to the sternocleidomastoid muscle and laterally to the internal jugular vein. Except in case of anatomic variation, the VA V2 segment is protected by the transverse processes bone, even if a pathological process displaces the VA along its course between them. The safest technique to expose the VA V2 segment then is to reach first the transverse process by cutting the longus colli muscle. Afterward, dividing intertransversary muscles permits exposure of and safely controls the VA by following its course. If required, the VA V2 segment can even be freed by opening the transverse process as far as the dissection is performed in the subperiosteal plane. In fact, the VA V2 segment is surrounded by a venous plexus and a periosteal sheath. This sheath gives a plane out of which the dissection is safe, avoiding troublesome venous bleeding or VA damage. RESULTS: This technique is very efficient for degenerative disorders, hour glass tumors, and vascular surgeries. CONCLUSION: Exposure and control of the VA V2 segment is safe if anatomy and variations are perfectly known, and if a rigorous step-by-step surgical technique is followed.

Angiography↗

PubMed2005

Progression of an osteoid osteoma to an osteoblastoma. Case report.

The authors report the unusual case of a 25-year-old man with occipitocervical pain related to a lesion of the C-1 lateral mass. Initially this lesion measured 8 mm and exhibited radiological features of an osteoid osteoma. Seven years later, as pain increased and became unresponsive to antiinflammatory drugs, computerized tomography scanning demonstrated progression to a 16-mm lesion, highly suspicious of an osteoblastoma. After mobilization of the vertebral artery from the C-1 groove, the lesion was completely resected via an anterolateral approach. Complete symptomatic relief, restoration of cervical range of motion and preservation of cervical stability were achieved immediately after surgery, and the results were confirmed at the 4-year follow-up examination. Pathological examination of tissue samples confirmed the diagnosis of osteoblastoma. Osteoid osteoma rarely evolves to osteoblastoma. Deterioration of a patient's ability to control pain is a warning sign. Insight into such cases underlines the importance of close long-term radiological follow-up examination in patients with conservatively treated osteoid osteomas.

Adult↗

PubMed2005

Cervical dumbbell intra-extradural hemangioblastoma: total removal through the lateral approach: technical case report.

OBJECTIVE AND IMPORTANCE: Extradural hemangioblastomas account for 8 to 12% of all spinal hemangioblastomas. Among them, intra-extradural forms with a dumbbell extension are extremely rare. We report a case of intra-extradural hemangioblastoma involving the C6 cervical nerve root. CLINICAL PRESENTATION: The patient was a 31-year-old woman presenting with signs of myelopathy and C6 radiculopathy on the right side. A computed tomographic scan and magnetic resonance imaging demonstrated a dumbbell tumor that had developed through the C5-C6 intervertebral foramen. Angiography revealed a well-circumscribed mass with feeders from the vertebral artery and the deep cervical artery. INTERVENTION: The tumor was totally removed through the lateral approach, with control of the vertebral artery and sacrifice of the C6 cervical nerve root. Limited bone drilling to enlarge the foramen permitted us to reach and resect the intradural component. Histopathological examination confirmed the diagnosis of hemangioblastoma. Follow-up was uneventful. CONCLUSION: This is the sixth reported case of a cervical dumbbell hemangioblastoma investigated by computed tomographic scanning and MRI but the first one resected via the lateral approach. The lateral approach seems appropriate for surgical resection because it provides primary control of the vascular feeders and access to the extradural and intradural components.

Adult↗

PubMed2004

Case report: greater meningeal inflammation in lumbar than in ventricular region in human bacterial meningitis.

Differences in the composition of ventricular and lumbar cerebrospinal fluid (CSF) based on single pairs of samples have previously been described. We describe a patient that developed post-surgical recurrent meningitis monitored by daily biochemical and bacteriological CSF analysis, simultaneously withdrawn from lumbar space and ventricles. A 20-year-old Caucasian man was admitted to the ICU after a resection of a chordoma that extended from the sphenoidal sinus to the anterior face of C2. CSF was continuously leaking into the pharyngeal cavity after surgery, and three episodes of recurrent meningitis, all due to Pseudomonas aeruginosa O12, occurred. Our case showed permanent ventricular-to-lumbar CSF gradients of leukocytes, protein and glucose that were increased during the acute phase of meningitis, with the greatest amplitude being observed when bacteria were present in both ventricular and lumbar CSF. This might suggest a greater extent of meningeal inflammation in the lumbar than in the ventricular region. Our case also showed that the increase in intravenous antibiotics (cefepim from 8 to 12 g/day and ciprofloxacine from 1.2 to 2.4 g/day) led to an increase in concentration in plasma but not in CSF.

Adult↗

PubMed2003

Cavernous sinus exenteration for invasive cranial base tumors.

OBJECTIVE: Invasive tumors involving the cavernous sinus, such as recurrent benign meningiomas or sarcomas, raise therapeutic problems that may be resolved by cavernous sinus exenteration (CSE). METHODS: Our series comprises 18 patients (9 women and 9 men ranging in age from 14 to 64 yr) who underwent CSE during the past 8 years. The tumors in these patients included 12 meningiomas, 3 chondrosarcomas, 1 rhabdomyosarcoma, 1 lipomyosarcoma, and 1 epidermoid carcinoma. Preoperative occlusion of the internal carotid artery was confirmed in 15 cases by a balloon occlusion test. Three patients had a negative balloon occlusion test, and their internal carotid arteries were preserved (n = 1) or revascularized (n = 2) through an external carotid artery-to-middle cerebral artery bypass. RESULTS: CSE was performed as a primary treatment in 5 patients and after one to five recurrences in 13 patients. In all patients, CSE included the internal carotid artery and Cranial Nerves III, IV, and VI and one to three branches of Cranial Nerve V. Orbital exenteration was performed in eight patients, and partial hypophysectomy was performed in five patients. Ten patients had received radiotherapy before CSE, and five patients underwent irradiation after CSE. The operative mortality includes two patients. Cerebrospinal fluid leakage was the main complication in four patients, with three patients having meningitis. Follow-up ranged from 6 months to 5 years, with three deaths from new recurrences at 2, 3, and 4 years after CSE. As compared with their clinical courses before CSE, all patients except the two who died postoperatively benefited from CSE. CONCLUSION: CSE has useful indications in invasive and rapidly growing tumors, including apparently benign meningiomas. A better understanding of the biological behavior of these tumors is necessary for appropriate selection of patients for CSE.

Adolescent↗

PubMed2002

Suboccipital and cervical chordomas: the value of aggressive treatment at first presentation of the disease.

OBJECT: Chordoma is a locally invasive tumor with a high tendency for recurrence for which radical resection is generally recommended. To assess the benefits of aggressive treatment of chordomas, the authors compared results in patients treated aggressively at the first presentation of this disease with results in patients who were similarly treated, but after recurrence. METHODS: Among 36 patients with cervical chordomas who were treated at the authors' institution, 22 underwent primary aggressive treatment (Group A) and 14 were treated secondarily after tumor recurrence (Group B). Two cases were excluded from Group A because of unrelated early deaths and three from Group B because of insufficient pre- or postoperative data. Most tumors were located at the suboccipital level and only eight cases at a level below C-2. Radiotherapy and proton therapy were similarly conducted in both groups of patients. The actuarial survival rates were 80 and 65% at 5 and 10 years, respectively, in Group A patients and 50 and 0% at 5 and 10 years, respectively, in Group B patients (p = 0.049, log-rank test). The actuarial recurrence-free rates were 70 and 35% at 5 and 10 years, respectively, in Group A and 0% at 3 years in Group B (p < 0.0001, log-rank test). The numbers of recurrences per year were 0.15 in Group A and 0.62 in Group B (p > 0.05). All other parameters that were analyzed (patient age, delay before diagnosis, clinical symptoms, chondroid type of lesion, and histological features) did not prove to influence prognosis in a statistically significant manner. CONCLUSIONS: Aggressive therapy, combining as radical a resection as possible with radiotherapy, seems to improve the prognoses of suboccipital and cervical chordomas when applied at the patient's first presentation with the disease.

Adolescent↗