Table 2. Various clinical and laboratory features of neuronal ceroid lipofuscinoses.

Parameter	CLN1 n  = 21 (35%)	CLN2 n  = 21 (41.66%)	CLN 6 n  = 5 (8%)	CLN7 n  = 3 (5%)	CLN8 n  = 3 (5%)
Mean age of presentations	9.9 months	2 years 10 months	4 years 2 months	2 years 3 months	3 years 2 months
Developmental delay	12 (57)	16 (64)	3 (60)	2 (66)	2 (66)
Regression	21 (100)	25 (100)	5 (100)	3 (100)	3 (100)
Abnormal eye findings	15 (71)	23 (92)	2 (40)	3 (100)	2 (66)
Epilepsy	21 (100)	25 (100)	5 (100)	3 (100)	3 (100)
Myoclonic epilepsy	18 (86)	25 (100)	5 (100)	3 (100)	3 (100)
Involuntary movements	21 (100)	25 (100)	5 (100)	3 (100)	3 (100)
Electroencephalography
PPR at low IPS frequencies of 1 to 3 Hz	0	04 (16)	0	0	0
Periodic discharges	0	1	0	0	1
Multifocal epilepsy	13 (21)	20(33)	4(6)	2(3)	2(3)
Magnetic resonance imaging of brain
Thalamus	10 (47)	2 (8)	0	0	01 (33)
Caudate	13 (62)	2 (8)	0	0	0
Cerebellar and cerebral atrophy	21 (100)	25 (100)	5 (100)	3 (100)	3 (100)
Electron microscopy done in	16	22	4	0	1
Abnormal	6 (37)	10 (45)	2 (50)		1 (100)
Curvilinear inclusions	4	8	0		1
GRODS	1	2	2
Curvilinear + GRODS	1	0	0
Enzyme assay done	20	26	5	1	3
Low levels of enzyme	15	21	Normal	Normal	Normal
Pathogenic variant by genetic testing	4	5	4	3	3

Abbreviations: GRODS, granular round osmiophilic deposits; IPS, intermittent photic stimulation; PPR, photoparoxysmal response.