Cervical-to-petrous internal carotid artery saphenous vein in situ bypass for the treatment of a high cervical dissecting aneurysm: technical case report.

OBJECTIVE AND IMPORTANCE: We describe a novel cervical-to-petrous internal carotid artery (ICA) saphenous vein in situ bypass for the treatment of a high cervical dissecting aneurysm. The cervical ICA has no major collateral branches and can be used as a tunnel for the vein graft. CLINICAL PRESENTATIONS: A 25-year-old man was involved in a car accident. A cerebral angiogram revealed a right ICA dissection with aneurysm formation at the C1-C2 level. The patient recovered fully and was anticoagulated. Six months after the initial angiogram, a second angiogram disclosed ICA stenosis (80%) and persistence of the traumatic dissecting aneurysm. Definitive surgical bypass was considered the most appropriate course of action. TECHNIQUE: The horizontal portion of the petrous ICA was exposed by an extradural subtemporal approach. The cervical arteries were exposed by a separate surgical incision. After dividing the petrous ICA and the cervical ICA, the cervical ICA was dilated using a Fogarty balloon embolectomy catheter. A saphenous vein graft was inserted inside the lumen of the cervical ICA and was anastomosed to the ICA end-to-end both proximally and distally (cervical-to-petrous ICA in situ bypass). The graft was patent on the follow-up angiogram. CONCLUSION: We describe a new technique that could be considered an alternative to the classical extra-anatomic cervical-to-petrous ICA bypass procedures.

Disco-computed tomography in extraforaminal and foraminal lumbar disc herniation: influence on surgical approaches.

Between January 1990 and February 1992, a total of 301 patients underwent discectomy for lumbar disc herniation; 29 had an extreme lateral herniation, i.e., foraminal or extraforaminal. The intervertebral foramen is a three-dimensional area demarcated primarily by the pedicles; we call it the lateral interpedicular compartment. The extraforaminal zone is the space outside the lateral border of the pedicles. All patients were evaluated by computed tomography (CT), water soluble myelography, postmyelographic CT scanning, or magnetic resonance imaging. Fifteen patients consecutively underwent disco-enhanced CT to adjust a correct diagnosis and to distinguish extraforaminal from foraminal herniation. In 10 cases of extraforaminal herniation, a selective radicular decompression with good-to-excellent clinical results was achieved by an extra-axial lateral decompression of the interpedicular compartment, with preservation of the facet joint. The operative target was the lateral aspect of the pars interarticularis and not the intertransverse space, as previously described. In two cases of both foraminal and extraforaminal herniation, the same technique was used. Fourteen patients with foraminal disc herniation and three patients with both foraminal and extraforaminal herniation underwent a standard intervertebral foraminotomy. An accurate preoperative diagnosis established by disco-CT is crucial in order to select the most suitable surgical approach.

Hearing preservation after acoustic neurinoma operation.

Between 1981 and 1984, 44 patients underwent acoustic neurinoma removal by a posterior cranial fossa approach with an attempt to preserve hearing. Seven tumors were small (less than 20 mm), 28 were medium (20 to 40 mm), and 9 were large (greater than 40 mm). Preoperatively, 4 patients had normal hearing, 15 had serviceable hearing, 10 had poor hearing, and 15 had no hearing. Postoperative hearing was preserved in 11 cases. Of the 19 patients with normal or serviceable hearing, 8 (42%) had serviceable hearing preserved postoperatively. Hearing preservation was achieved in 43% of the patients with small tumors, 25% of those with medium tumors, and 11% of those with large tumors. This study confirms the value of the suboccipital approach, which can be used in an attempt to preserve hearing whenever the patient has serviceable hearing preoperatively and whenever the tumor size makes it feasible.

Magnetic resonance imaging stereotactic target localization for deep brain stimulation in dystonic children.

OBJECT: The actual distortion present in a given series of magnetic resonance (MR) images is difficult to establish. The purpose of this study was to validate an MR imaging-based methodology for stereotactic targeting of the internal globus pallidus during electrode implantation in children in whom general anesthesia had been induced. METHODS: Twelve children (mean follow up 1 year) suffering from generalized dystonia were treated with deep brain stimulation by using a head frame and MR imaging. To analyze the influence of distortions at every step of the procedure, the geometrical characteristics of the frame were first controlled using the localizer as a phantom. Then pre- and postoperative coordinates of fixed anatomical landmarks and electrode positions, both determined with the head frame in place, were statistically compared. No significant difference was observed between theoretical and measured dimensions of the localizer (Student's t-test, ¿t¿ > 2.2 for 12 patients) in the x, y, and z directions. No significant differences were observed (Wilcoxon paired-sample test) between the following: 1) pre- and postoperative coordinates of the anterior commissure (AC) (deltax = 0.3+/-0.29 mm and deltay = 0.34+/-0.32 mm) and posterior commissure (PC) (deltax = 0.15+/-0.18 mm and deltay = 0.34+/-0.25 mm); 2) pre- and postoperative AC-PC distance (deltaL = 0.33+/-0.22 mm); and 3) preoperative target and final electrode position coordinates (deltax = 0.24+/-0.22 mm; deltay = 0.19+/-0.16 mm). CONCLUSIONS: In the authors' center, MR imaging distortions did not induce detectable errors during stereotactic surgery in dystonic children. Target localization and electrode implantation could be achieved using MR imaging alone after induction of general anesthesia. The remarkable postoperative improvement in these patients confirmed the accuracy of the procedure (Burke-Marsden-Fahn Dystonia Rating Scale score delta = -83.8%).

Intraoperative facial nerve monitoring in posterior fossa acoustic neuroma surgery.

Intraoperative facial nerve monitoring has become an indispensable tool during cerebellopontine angle surgery. Ninety-seven patients underwent surgical removal of an acoustic neurinoma with the use of a pneumatic sensor monitoring between January 1, 1986, and December 31, 1990. In the early postoperative period, a normal or near-normal facial function (grades I and II) was achieved in 86% of the patients, a moderate dysfunction (grade III) was present in 7%, and a total or severe dysfunction (grades V or VI) was present in 6%. Normal function at 1 year was achieved in 90.5% of the patients, 4% were grade II, a moderate dysfunction (grade III) was present in 2%, and 3% showed a total or severe dysfunction (grade V and VI). The incidence of normal function decreased with tumor size, with an occurrence rate of 100%, 94%, and 91% in small, medium, and large tumors, respectively. In eight consecutive patients, all responses detected by the monitoring during the operation were collected and analyzed according to intraoperative events. Analysis of the results indicate that 95% of the 316 mechanically induced stimulations were of small or extremely small amplitude, and only 5% were of moderate amplitude. A medial-to-lateral strategy of dissection, preservation of the arachnoid veil over the facial nerve, a control by the monitoring of the amount of traction, and a more widespread use of sharp dissection were the major approaches to reduce surgical trauma during dissection.

Possible influence of cerebrospinal fluid pressure on the growth of a third ventricle choroid plexus papilloma.

A case of histologically proven benign choroid plexus papilloma of the third ventricle in a 4-month-old male child is reported. The clinical symptoms and the neuroradiologic findings were those of a supratentorial hydrocephalus. A shunting procedure was performed after refusal by the family of a direct surgical approach. Subsequently there was a four- to fivefold increase in volume of this tumor in less than 4 months under decreased cerebrospinal fluid pressure. The purpose of this report is first to add a case to 27 cases of papilloma of the choroid plexus of third ventricle reported in the medical literature. Secondly to underline a possible influence of intraventricular pressure on the growth of a histologically benign intraventricular papilloma. Subsequently, the question of radiation therapy may be raised, if total removal of the papilloma is not obtained, especially in view of decreased cerebrospinal fluid pressure provided by the previous shunting procedure.

Intraventricular administration of morphine in patients with neoplastic intractable pain.

Since February 1981, eight patients with neoplastic intractable pain have been treated by intracerebroventricular administration of small doses of morphine. Morphine was injected into the cerebrospinal fluid through a ventricular reservoir either by direct puncture or by self-administration. Clinical results were very good, and there were no deleterious effects.

Early restructuration of consciousness after traumatic coma.

Recovery of consciousness after acute brain injury is a remarkable phenomenon, yet, not completely understood. We describe the early clinical stages of recovery of consciousness in 48 selected patients by means of different items of the Glasgow Coma and Liege Coma Scales. Arousal, expressed by the stimulated opening of the eyes (E2) was correlated with the appearance of the localizing pain response (M5), with the capacity to obey commands (M6), with the opening of the eyes (E4) and with the blink reflex (R5). This study confirms the classical clinical sequence of arousal and recovery of consciousness characterized by the consecutive appearance of E2, R5, E4, M5 and M6. When the appearance of E2 and R5 are considered separately, we noticed a significant difference, suggesting different structural and functional brain recovery processes.

[Bacterial abscesses of the spinal cord. Review of the literature (73 cases)]. / Abcès bactériens de la moelle épinière. Revue de la littérature (73 cas).

Intramedullary spinal cord abscesses are an uncommon entity with 73 cases reported in the literature; the first case was reported in 1830. Sixty-seven percent of abscesses occur in the first 4 decades of life. Staphylococcus and Streptococcus are the most common organisms; 25% of patients have negative intraoperative cultures. The primary source of the infection could be found, in only 45% of patients. Most of these infections are secondary to metastatic spread from infections of the lung, endocarditis, genitourinary tract; 10 reports have described an intramedullary abscess secondary to a dermal sinus. The signs and symptoms depend on the location of the lesion; the thoracic spine is the most commonly area involved. Patients are usually divided into three clinical groups; acute onset (symptoms less than 1 wk), subacute onset (symptoms up to 6 wk), and chronic course (symptoms more than 6 wk). Patients with the acute form are more likely to have a fever and an elevated white blood cell count and may show either a partial or complete transverse myelitis picture. The patients with chronic abscesses are less likely to have fever and leukocytosis, and their symptoms often mimic those of an intramedullary spinal tumour. The erythrocyte sedimentation rate tends to be elevated in all patients regardless of their clinical findings. CSF cultures are usually sterile. Plain x-rays of the spine are often normal. A myelogram in conjunction with a computed tomographic scan may show the intramedullary lesion. MRI studies usually demonstrate intramedullary lesions with exceptional clarity; the use of gadolinium with T1-weighted MRI studies enhances the abscess wall.(ABSTRACT TRUNCATED AT 250 WORDS)

[Arachnoid cysts and subdural hematomas]. / Kystes arachnoïdiens et hématomes sous-duraux.

Arachnoid cysts of the middle cerebral fossa is a not uncommon lesion which can occur in young subjects, sometimes after minimal head trauma. Subdural hematomas and sometimes intracystic hemorrhage may develop. We report a personal series of seven cases seen in young subjects (6-24 years). Clinical presentation was not specific, the complication usually being revealed by signs of intracranial hypertension. The pathogenesis of subdural hematoma is discussed. Magnetic resonance imaging is the most useful diagnostic tool, providing excellent tissue specificity, although CT scan is often used to visualize a subdural hematoma and subsequent arachnoid cyst. Treatment relies on surgery to empty the subdural hematoma and remove compression. There has been no real consensus on treatment modalities. Long-term prognosis is good in most cases.

[Cyst of the conus masquerading as motor neuron disease]. / Kyste du cône médullaire simulant une maladie du motoneurone.

We report on a patient presenting with rapidly progressive painless paraplegia, amyotrophy and fasciculations masquerading as motoneuron disease. There were no bowel or bladder involvement but the patient noted mild paresthesia on the external part of the right foot and hypertrophy of the right calve was present. While lumbar CT Scan was normal, MRI showed a large cyst of the conus. Analysis of the cyst concluded to a benign cyst of the conus. Paraplegia resolved after surgery and after one year, no relapse was observed so that an hidden ependymoma appeared unlikely.

[Prolonged traumatic and vascular coma: prognostic and therapeutic indications based on hemodynamic and metabolic studies]. / Comas traumatiques et vasculaires prolongés: indications pronostiques et thérapeutiques d'après une étude hémodynamique et métabolique

From haemodynamic and metabolic investigation of 65 comatose subjects following cranial traumatism or cerebral vascular accident, the following prognostic and therapeutic indications emerged: The isolated increase in oxygen pressure in the jugular vein to above 50 mm Hg, the simultaneous decrease in circulation of the brain to below of 30 ml/100g/min., and of the brain consumption of oxygen to below 1.5 ml/100g/min., combined with a loss of autoregulation and a decrease in carbon dioxide reactivity indicate that prognosis is very poor. Induced arterial hypertension, associated with hyperventilation, partially corrects brain hypoperfusion in coma from bulbo-pontine lesions. Sodium penthiobarbital and sodium gamma hydroxybutyrate and have the effect of reducing oxygen metabolism which might have some therapeutic value during the acute phase of coma. Clomipramine which has a stimulating effect on oxygen metabolism should be kept in reserve for the chronic phase of prolonged coma.

[Symptomatic aneurysms of the postero-inferior cerebellar artery. A multicenter retrospective study of 29 cases]. / Anévrysmes symptomatiques de l'artère cérébelleuse postéro-inférieure. Etude rétrospective multicentrique de 29 cas.

A multicenter retrospective study of 29 cases of posterior inferior cerebellar artery is reported. Over a period of 21 years, the frequency of posterior inferior cerebellar artery aneurysm among all intracranial aneurysm was estimated to 1.38 p. 100 of cases of aneurysms followed by 3 University Hospitals. Frequency of rupture appeared to be very high (93 p. 100) in this series probably because of the type of selection. Average grade of presentation according to Hunt and Hess classification being < III in 3 fourth of the cases. Neither clinical presentation nor suspicious etiological factors were specific of this localization. Only two cases were of pseudotumoral appearance. Positive diagnosis of subarachnoid hemorrhage was made by CT scan. Angiograms gave diagnosis of localization of the malformation and its type. Intraventricular hemorrhage was found in 62 p. 100 of our cases: all had hemorrhage of the fourth ventricle. Hydrocephaly was more frequent as compared to supratentorial localizations, Vasospasm was less frequent as in supratentorial localizations. Nimodipin seems to be efficient. Therapeutic possibilities are primary dominated by surgery with good results when it is possible. Endovascular treatment is under evaluation.

[Scoliotic malformations with or without associated occult spinal dysraphia. A study in 82 children. Current radiological techniques, indications and findings]. / Scolioses malformatives, avec ou sans dysraphie spinale occulte. A propos de 82 observations de l'enfant. Techniques radiologiques actuelles, séméiologie et indications.

The possible association of spinal dysraphia with scoliotic malformations was studied in 82 children. Scoliotic malformations are not always the result of dysraphic malformations (diastematomyelia, hydromyelia, intrathecal lipoma, medullary cone ectopia). Recognition of dysraphic scoliotic malformations from among other types of scoliotic malformations can be accomplished before myelography by detecting vertebral malformations on standard films and, if necessary, by computed tomography. Segmental vertebral malformations, affecting vertebral bodies only, do not appear to arise from malformations of nerves. On the contrary, however, dysraphic lesions are always associated with vertebral neural malformations. Of currently employed techniques, only myelography with metrizamide, followed by computed tomography, gives the maximum amount of data concerning the lesions. Even the association of these two techniques does not demonstrate the presence of certain intrathecal fibrous lesions, due to lack of resolution.

[Dura mater chondroma. A case report and review of the literature]. / Chondrome dure-mérien. A propos d'un cas et revue de la littérature.

Intradural chondromas are exceedingly rare intracranial tumors. We present a case of intradural chondroma. It is a clinical and radiological presentation, with special emphasis on CT appearance. The CT scan demonstrated a mass lesion with intratumors calcification areas, and slight enhancement after intravenous injection of contrast. The differential diagnosis with calcified meningioma is histological.

[Ectopic intraspinal extradural anaplastic ependymoma in an infant]. / Ependymome anaplasique ectopique intrarachidien extradural chez un nourrisson.

BACKGROUND: Ependymomas represent about 10% of the spinal tumors in children. Some of them may be unusually located. CASE REPORT: A 10-month-old boy was admitted for an abdominal mass syndrome with dehydration asthenia and acute bladder dysfunction. A few hours later, he developed a flaccid paraplegia. Ultrasonic and magnetic resonance spinal imaging showed a giant intraspinal tumor extending from T9 to IA level, posteriorly located to the dural compartment, widening the spinal cord. Ultrasonography also showed right ureterohydronephrosis due to the neurological bladder dysfunction. A conservative laminotomy-laminoplasty was performed in emergency. Total removal of the tumor that was attached to the right dorsal root was achieved extradurally, requiring resection of the proximal part of the root. Histological features were typical of malignant ependymoma. Chemotherapy was initiated 2 weeks later. The severe renal destruction and the persistent bladder dysfunction led to a heminephrectomy and a cystostomy, 3 weeks later. The neurological recovery was only partial with a follow-up of 18 months. CONCLUSION: Ectopic intraspinal extradural localization of ependymomas is rare and their development from a nerve root is exceptional.

[Possibilities of preserving hearing in the surgery of acoustic neurinoma]. / Les possibilités de conservation de l'audition dans la chirurgie des neurinomes de l'acoustique.

Between 1981 and 1984, 44 patients underwent acoustic neurinoma removal by a posterior cranial fossa approach in an attempt to preserve hearing. 7 tumors were small (less than 20 mm), 28 were medium (20 to 40 mm) and 9 large (greater than 40 mm). Of these 44 patients, 4 had normal hearing preoperatively, 15 had serviceable hearing, 10 non-serviceable hearing and 15 anacousis. Postoperative hearing was preserved in 11 cases. Of the 19 patients with normal or serviceable hearing, 8 (42%) had serviceable hearing preserved postoperatively. Hearing preservation was achieved in 43% of small tumors, 25% of medium tumors and 11% of large tumors. This study stress the importance of the suboccipital approach which can be used in an attempt of hearing preservation whenever the patients have serviceable hearing preoperatively and whenever the tumor size makes it feasible.

[Neurosurgical treatment of intracranial aneurysms]. / Traitement neurochirurgical des anévrysmes intracrâniens.

This text summarizes the course organized for residents and trainees by the Société de Neurochirurgie de Langue Française. It was presented by the authors during the annual winter meeting held in Paris in December 1992. The aim of this course was to discuss all the technical points needed to achieve safely a microsurgical clipping of an intracranial aneurysm of the anterior circulation. Although many of these technical points discussed can apply to any kind of intracranial aneurysm, the very specific difficulties of the treatment of giant aneurysms or posterior circulation aneurysms were not mentioned. The usual pterional approach is described. The need of having a slack brain to perform easily the dissection of the aneurysm is stressed. Standards of hemodynamic control during surgery are described either with the use of a total or a proximal temporary clipping under the electrophysiologic control of the somesthetic evoked potential. Prevention of peroperative cerebral ischemia and brain protection are discussed. Dissection of the aneurysm is presented step by step until clipping. Different ways of clipping are discussed after a short description of the characteristics and composition of various available clips. How to deal with a premature intra-operative rupture of the aneurysm is also discussed. The last chapter describes step by step the approach and clipping of the four most frequent aneurysm locations i.e. at the posterior face of the intracranial internal carotid artery, the intracranial carotid bifurcation, the middle cerebral artery, and the anterior communicating artery.

[Effects of ultrasonic aspiration on the sciatic nerve of rats. Experimental study]. / Effets du bistouri à ultra-sons sur le nerf sciatique du rat. Etude expérimentale.

We report the effects of induced ultrasonic lesions on the sciatic nerve of the rat. Using different level of intensity (5 to 35%) and time exposure (5 to 60 seconds) for each application, we study the effects by action potential recording, microphotography and histological study. The nerve remains unaltered for low intensity (5 to 10%) until a time exposure of 20 seconds. Beyond that level, a progressive severity of the lesion is documented from oedema to contusion. A safe use of the surgical ultrasonic aspiration in the vicinity of nerves and roots must have a low intensity level, reducing the risks of direct contact between nerve and sonoprobe.

[Sub-temporal supra-petrous approach to the horizontal portion of the sub-petrous internal carotid artery. Technique, indications, incidents and accidents]. / Exposition par voie sous-temporale sus-pétreuse de l'artère carotide interne intra-pétreuse dans sa portion horizontale. Technique, indications, incidents et accidents.

Cavernous sinus exploration, anterior middle fossa transpetrous approach, and saphenous vein graft bypass require proximal control of the horizontal segment of the petrous internal carotid artery. Exposing the petrous portion of the internal carotid artery is not without the potential for serious complications (cochlea, facial nerve, auditory tube, musculus tensor tympani). With guidance from the classicaly landmarks within Glasscock's triangle, the bony petrous carotid canal can be unroofed. The authors describe an alternative method for obtaining direct vascular control under the trigeminal ganglion, safety unroofing of the carotid canal and control of the posterior face of the carotid bend. The indications, advantages, and disadvantages of this approach are described in details, along with its use in seven patients.