With the objective of making calcium alginate gel beads with small and uniform size, membrane emulsification coupled with internal gelation was proposed. Spherical gel beads with mean size of about 50 μm, and even smaller ones in water, and with narrow size distribution were successfully obtained. Experimental studies focusing mainly on the effect of process parameters on bead properties were performed. The size of the beads was mainly dependent on the diameter of the membrane pores. High transmembrane pressure made for large gel beads with wide size distribution. Low sodium alginate concentration produced nonspherical beads, whereas a high concentration was unsuitable for the production of small beads with narrow distribution. Thus 1.5% w/v was enough. A high surfactant concentration favored the formation of small beads, but the adverse effect on mass transfer should be considered in this novel process. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 848–852, 2003

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Neurologic outcome following surgery was favorable in the vast majority of patients, with no mortality or significant morbidity. Surgery is the only treatment in elderly patients with symptomatic spinal meningiomas, even those with a poor preoperative neurologic condition, whenever there is an acceptable risk from an anesthesiological point of view.

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We speculate that alteration of spinal cord blood flow by stretching of the cervical spinal cord and spinal epidural venous engorgement might have caused this devastating complication.