Preliminary experience with phase-contrast magnetic resonance (MR) angiography at 0.5 T applied in 12 cases of vascular malformations of the spinal cord is reported. There were six intramedullary arteriovenous malformations (AVMs), four perimedullary fistulas, and two dural arteriovenous fistulas with perimedullary drainage, all proved with x-ray angiography. The small size of the vessels and their location within a bony structure presented a technical challenge. Serpentine vascular signal patterns were identified within the spinal canal in all cases, showing good correlation with the x-ray angiographic pattern. Relative to spin-echo images, MR angiograms allowed better visualization of the venous drainage. The nidus of intramedullary AVMs was more difficult to recognize. The ability to manipulate the velocity-encoding value allows better characterization of flow speed. The results underline the two dimensions of the phase-contrast technique, which provides both anatomic images and dynamic information about vascular malformations. MR angiography does not replace selective x-ray angiography, which is indispensable for therapeutic strategy (endovascular procedure or surgery), but it can be considered a valuable alternative to x-ray angiography during follow-up.

Adult↗

PubMedDate not supplied

[Point of view of the neurosurgeon].

Stereotactic radiosurgery, a term introduced by Leksell, was born more than 40 years ago, but has made great strides for the last 15 years. There is no consensus among neurosurgeons as to the best device (gamma knife, linear accelerator), the treatment doses, and the clinical indications of stereotactic radiosurgery. Therefore, this report is the viewpoint of one neurosurgical team only. In the radiosurgery literature, there is no clear evidence of better results with the gamma-knife or the linear accelerators. With regard to clinical applications, cerebral arteriovenous malformations are the more widely accepted indications of radiosurgery, since a cerebral angiography can confirm the disappearance of the nidus of an arteriovenous malformation treated by stereotactic radiosurgery. Usually, small and deep arteriovenous malformations can be treated by stereotactic radiosurgery only. Nevertheless, the treatment of the other arteriovenous malformations more often require procedures including one or several of the following treatment methods: microneurosurgery, interventional neuradiology, stereotactic radiosurgery. Stereotactic radiosurgery in acoustic schwannomas, skull base meningiomas, especially those involving the cavernous sinus, brain metastases, and pituitary tumors seem attractive. Contrary to arteriovenous malformations, the lack of criteria for cure requires a long follow-up and carefully controlled trials to confirm the efficiency of stereotactic radiosurgery for these tumors. On the other hand, experience of stereotactic radiosurgery for astrocytomas and glioblastomas is limited, and few publications are available. Furthermore, because of the infiltrating growth, a major impact of stereotactic radiosurgery for these tumors is presumably not to be expected. Lastly, a close multidisciplinary approach seems absolutely necessary to define the best indications of stereotactic radiosurgery and to improve its clinical results.

Humans↗

PubMedDate not supplied

[Our technique of hetero-lateral facio-facial anastomosis by means of nerve autografting in the treatment of permanent peripheral facial paralysis].

The authors describe the technique used in 12 surgical cases of heterolateral facio-facial anastomosis by nerve autograft in the treatment of permanent peripheral facial paralyses. Their main contention is that section of 50 p. 100 of the neurones of the peripheral branches of the facial nerve on the unaffected side does not impair motricity to any extent and that it therefore is possible to anastomose the proximal portion of some healthy branches to the corresponding distal portion of the affected side by placing between them a graft from the external saphenous nerve. The principles for fascicular suture as defined by Seddon and later by Millesi are followed. The technique differs from that made popular by Smith and later by Smii inasmuch as: --the bilateral, hidden face-lift incision makes possible a final passive musculotegumentary suspension of the paralysed side immediately improving the patient's appearance while the nerve re-establishes itself; --retrograde interfascicular dissection on the paralysed side allows precious centimetres to be gained; --pinpointing of the nerve suture area is possible by the placing of a silicone-coated ring with a clip some distance away.

Facial Nerve↗

PubMedDate not supplied