An instrument for holding a surgical tool or bone implant includes a handle with a bearing surface formed in one end for engaging the surgical tool. The repair method includes implanting the collagen scaffold during laser corneal ablation or other interlamellar surgery to improve visual acuity or to preclude the possibility of ectasia . One or more tubes are positioned within each of the solar troughs such that a heat-transfer fluid flowing through the tubes is heated by sunlight reflected from the solar troughs. As an additional benefit, the system provides a mechanism for call timing and billing so that an estimated bill may be generated based on connection time. The monitor may include an index-determining module configured to determine the fluid responsiveness index through formation of a ratio of one or both of amplitude or frequency modulation of the physiological signal to baseline modulation of the physiological signal.