ABSTRACT
Objective:To evaluate value of neuronavigator-assisted microsurgery of glioma located in cerebral functional areas.Methods:Patients with glioma located in cerebral functional areas were underwent operation in Xiangya Hospital.Of 64 patients,34 patients were performed neuronavigator-assisted microsurgery,and 30 were underwent routine surgical operation.Results:The neuronavigator-assisted microsurgery group showed high complete resection rate with low neurological deficit and cerebral edema compared with the routine surgical group (P＜0.05).Conclusion:Neuronavigator-assisted microsurgery is effective and characterized by accurate location,personalized operative incision design,and higher rate of tumor resection.
ABSTRACT
Connection between the superior colliculus(SC)and the dorsal and ventral lateral geniculate nuclei (LGd and LGv) were studied in adult golden hamsters using anterograde and retrograde pathway tracing methods 1. In four hamsters, the cytoarchitecture of the SC, LGd and LGv was examined in brain sections stained with Nissl's or Loyez's method. 2. A single injection of a mixture of ~3H-leucine and ~3H-proline was made into various regions of the SC in each of 4 animals (1 day survival) for studying the pattern of terminal distribution of the projections from the SC to the ipsilateral LGd and LGv. In animals where the injection site was located in the superficial gray layers of the lateral portion of the SC, labelled terminals were found in the caudal lateral part of the LGd and LGv. In the case where the injection was restricted in more medial part of the SC, the terminal labelling was observed in the rostral lateral portion of the lateral geniculate nuclei. 3. One day after an injection of horseradish peroxidase (HRP) into the LGd (4 animals), LGv(2 animals), or LP(2 animals) labelled neurons were observed in the superficial gray layers of the ipsilateral superior colliculus. No HRP-labelled neuron was detected in deeper laminae in the colliculus. These results indicate that neurons in the superficial gray layers of the SC project to the ipsilateral LGd and LGv, and the projections are organized topogra- phically according to the retinotopic or visual field map
ABSTRACT
A segment of autologous sciatic nerve was transplanted into the 17/18a borderoregion or near the midline of the occipital brain in the adult golden hamsters.After42-131 days survival time,HRP (50% in saline) was administered to the cut endof the graft.It was found that the neurons of different sizes and shapes in visualcortex can be induced to regenerate their fibers into the peripheral nerve graft forup to 10mm;Some of the regenerated cells became larger than that of the normal cells.in the visual cortex,which is similar to that in the retina,but the ability of regenera-tion of the cortical neurons is much lower than that of the retinal ganglion cells.Fluorescent dye double-labelling method was used and it was demonstrated thatthe callosal neurons in visual cortex can regenerate their fibers into peripheral nervegraft,the regenerative fibers originated from axotomized neurons rather than fromcollateral sprouting of undamaged neurons.Predegeneration treatment for the sciaticnerve did not enhance the regeneration of neurons in the visual cortex.Extradamagemade near the graft insertion does not seem to increase the quantity of regenerationcells in the visual cortex.The results of the experiment suggest that peripheral nerve graft can induceregeneration of neurons in visual cortex and the local environment is one of theimportant factors affecting the ability of regeneration of mammalian CNS.
ABSTRACT
After autologous transplantation of sciatic nerve segments into the retinae of adult golden hamsters for 1-4 months, anterograde and retrograde labelling with horseradish peroxidase demonstrated that ganglion cell axons have regrown into the peripheral nerve graft for a distance up to 2 cm. The regenerating axons into the grafts were distributed within fan-or beltshaped areas between the sites of grafting and the limbus of the retina, their numbers being greater for grafts near the optic disc than for those in the outer portions of the retina. Histogram of cell soma areas of labelled neurons from retinae with grafts indicated that all normal cell sizes were represented and there was a substantial population of enlarged neurons. Retrograde labelling with fluorescent dyes, Nuclear Yellow, applied to the optic tract and True Blue to the graft, demonstrated that the regenerating axons originated from axotomized ganglion cells rather than by axonal collateral sprouting of undamaged neurons.
ABSTRACT
Objective\ The present study was carried out to examine the relationship between the distance of axotomy and axonal regeneration systematically,and the effect of a pre\|degenerated peripheral nerve(PN) graft on axonal regeneration of retinal ganglion cells(RGCs) axotomized at different distances. Methods\ The optic nerve(ON) was transected at 0^5,1,1^5,2,3 or 7mm from the optic disc and a normal (the normal group) or pre\|degenerated(the pre\|degeneration group) PN graft was transplanted onto the ocular ON stump in adult hamsters. Results\ In both groups,the number of regenerating RGCs 28 days after grafting decreased significantly when the distance of axotomy increased from 0^5 to 7mm with a sharp decline between 0^5 and 3mm.When the corresponding distance points between the two groups were compared,enhanced regeneration was observed at 2 and 3mm in the pre\|degeneration group. Conclusion\ These results show that the distance of axotomy on the ON of adult hamsters is critical in determining the number of regenerating RGCs.The beneficial effect of a pre\|degenerated PN graft on axonal regeneration of axotomized RGCs is conditional on the distance of axotomy.\;