| 摘要 |
An instrument for penetrating body tissue has a rigid hollow shaft having at its distal end a penetrating point, which is at least partly transparent and which is conical, beveled or tapered; a hollow sleeve may surround the shaft. The instrument includes or can be associated with lighting and viewing elements. There may be provided a helical element at the penetrating point, having surfaces converging outwardly to a line. In another embodiment, the point comprises plural, flat, angularly related surfaces converging to a line, the point being at least partly transparent, as by being of opaque material having one or more openings closed by a transparent window. In a further embodiment, the point has a conical distal end and has along its side at least one and preferably two blade members which is/are at or rearwardly of the apex or distal end of the conical tip, and have surfaces converging to a linear edge coaxial with the axis of the point. |
