The case is also noteworthy because it documents Cushing's process for using a relatively new treatment strategy for a disorder with which he had relatively little prior experience. Cushing did not perform the treatment without first consulting Mills, an instructor of ophthalmology at Johns Hopkins who clearly expressed approval. Cushing also attempted to maintain follow-up by instructing the patient to write about his progress. Presumably, the fact that the patient did not report significant improvement at discharge (although he did report improvement in pain and stabilization of vision in subsequent correspondence) led to reluctance on the part of Cushing to publish his results and continue extirpation for patients with glaucoma. As the patient likely had chronic glaucomatous damage and resultant optic atrophy, the results may be less indicative of the efficacy of the operation than the fact that the patient's condition was irreversible. Nevertheless, we are limited by our inability to know what the patient's true diagnosis would be by present-day standards. The actual findings from his ophthalmologic exam were not recorded. However, an ophthalmoscope was presumably used because this tool had been developed nearly 50 years prior and had reached general acceptance by that time.37 Furthermore, fundoscopic examination findings were recorded in the Johns Hopkins surgical records for many of Cushing's other patients. According to Mills' note, IOP was also measured; however, the method used and thereby its accuracy are uncertain. Digital measurements of IOP using the index finger against a closed eye were the oldest, simplest, least expensive, and least accurate method in use at the time.14,16,38 In 1862, von Graefe had developed a transpal pebral tonometer.38 In the 1880s, following the emergence of local anesthetic in the form of cocaine, applanation tonometers were developed by von Graefe's student Maklakoff and Fick.38,39 The Schiotz tonometer, which would become widely used in the field, was invented in 1905.14,16,38,39 Nevertheless, the crucial fact remains that the extirpation of the superior cervical ganglion was performed on a patient understood to have glaucoma.