—We thank Dr Wiener for his comments regarding our article. He is correct in surmizing that two, rather than four, data acquisitions were utilized during the 120-ms TE and 2-s TR sequence on the 1.5-tesla unit; four data acquisitions are used on the 0.6-tesla unit. We regret the lack of clarity regarding this point. As he assumed, the third scan sequence was the result of software limitations at the time of the study, limitations no longer present. Finally, as noted above, only two signal acquisitions were utilized on the 1.5-tesla unit. We have found that we must use approximately twice as many data acquisitions on the 0.6-tesla unit in order to achieve a comparable signal-to-noise ratio. Measurements made at The Cleveland Clinic and elsewhere1-3 indicate that the contrast-to-noise ratio increases linearly with increasing field strength.
Lesser RP, Weinstein MA. Magnetic Resonance Imaging in Patients With Intractable Focal Seizures-Reply. Arch Neurol. 1987;44(4):361. doi:10.1001/archneur.1987.00520160005003
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