Table III.

Genetic and clinical characteristics of participants with Rett syndrome (RTT) who received single-photon emission-computed tomography (SPECT) of the brain for sixty (60) minutes, twenty-four (24) hours following the intravenous injection of approximately 333 MBq (9 mCi) (−)-5-[¹²³I]iodobenzovesamicol ([¹²³I]IBVM)

Age in years	MeCP2 mutation	X-inactivation	HCc	Walksa	Feeds selfb	ADLSc	Medications	Hd	Rd	Sd	Scd
19	T158M	Random	54 (35%)	0	0	0	phenobarbital	1	2	1	1
21	R306C	Skewed	50 (<2%)	2	1	2	carbemazepine, valproic acid	0	0	1	1
22	R294X	Random	48.5 (<2%)	0	0	0	levetiracetam, valproic acid	0	2	1	3
31	R270X	Random	53.3 (10%)	1	1	1	fluoxetine	1	1	0	1

HCc = head circumference in centimeters with percentiles in parentheses; H = hyperventilation; R = rigidity; S = seizures; Sc = scoliosis;

^a0 = cannot walk; 1 = walks with assistance; 2 = walks without assistance

^b0 = cannot feed self; 1 = can feed self

^cScores on Activities of Daily Living Scale (ADLS)

0 = neither walks nor feeds self

1 = walks with assistance and feeds self

2 = walks without assistance and feeds self

^dScores for H, S, Sc, and R: 0 = none. 1 = mild. 2 = moderate, 3 = severe.