 In 1984, after rising to the rank of full professor, Phelps was appointed chair of the university's ophthalmology department, widely recognized as one of the foremost eye clinics in the country.Soon afterward, he was diagnosed with cancer.He died eighteen months later at the age of 47, survived by his wife Margaret Dorsey Phelps, whom he married in 1964, his four children, his parents, and his brothers.