Occipital Deep White ·Matter Hyperintensity as Seen by MRI: 1. Clinical Significance Masahito Miyazaki, MD, Toshiaki Hashimoto, MD, Masanobu Tayama, MD and Yasuhiro Kuroda, MD
Magnetic resonance imaging was performed in 270 patients with various neurologic complaints (1-15Y) with a 0.5 tesla superconducting imaging system using a field echo Tl-weighted sequence and spin echo T2-weighted and PD-weighted sequences. Twenty-seven of them had deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images. The frequency of mild DWMH differed in different age groups, suggesting that mild DWMH may result from delayed myelination in the central nervous system. However, the frequency of severe DWMH, which was revealed as isointense relative to cerebrospinal fluid, did not differ in different age groups and it was significantly more common in severely retarded patients. Classification of DWMH based on the signal intensity is valuable to distinguish white matter abnormalities in the occipital lobe from delayed myelination in the same site. Key words: MRI, T2-weighted image, deep white matter hyperintensity, mental retardation. Miyazaki M, Hashimoto T, Tayama M, Kuroda Y. Occipital deep white matter hyperintensity as seen by MRI: 1. clinical significance. Brain Dev 1992;14:150-5
Magnetic resonance imaging (MRI) allows a detailed examination of lesions in the white matter that include demyelination in the central nervous system. Information regarding clinical characteristics of lesions with a hyperintensity disclosed by a T2-weighted image in the periventricle and/or deep white matter has been accumulated mostly in adult patients (1-9]. Although a few reports exist concerning the pediatric population, the pathological significance of these lesions remains almost unknown. In this report, we have studied the clinical characteristics of children who were found to have deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images and tried to determine the difference between delayed myelination in the OCCipital white matter versus abnormalities, e.g. pathologic demyelination, in the same location.
From the Department of Pediatrics, School of Medicine, University of Tokushima, Tokushima Received for publication: January 11, 1992. Accepted for publication : March 9, 1992. Correspondence address: Dr. Masahito Miyazaki, Department of Brain Pathophysiology, Faculty of Medicine, Kyoto University, Shogoin-Kawaharamachi, Sakyo, Kyoto 606, Japan.
PATIENTS AND METHODS Two hundred and seventy patients who visited our hospital with various neurological complaints underwent MRI examination. The patients' age ranged from 1 to 15 years (mean 6.3 years). An MRI examination was performed with a 0.5 tesla superconducting imaging system (MRT50A, Toshiba Co) using a field echo sequence (TR/TE: 300 ms/14 ms) and spin echo sequences (TR/TE: 2,000 ms/ I 00 ms or 2,000 ms/ 120 ms, and 2,000 ms/30 ms). The thickness of each slice was 10 mm. DWMH was evaluated by a T2-weighted transaxial image (spin echo sequence TR/TE: 2,000 ms/IOO ms or 2,000 ms/120 ms) through the horizontal level of the body of the lateral ventricle or foramen of Monro, based on visual impression. DWMH type A was diagnosed when an area which was revealed as iso- or hyperintense relative to the gray matter but hypointense relative to cerebrospinal fluid (CSF) was disclosed in the deep white matter of the occipital lobe. DWMH type B was diagnosed when an area which was revealed as isointense relative to CSF was disclosed there (Figs 1, 2) [4,5]. All patients were neuropsychologically investigated to assess mental and motor function with intelligence quotient (IQ) or developmental quotient (DQ). IQ was evaluated using WISC-R and DQ was evaluated using
Fig 1 MRI: spin echo T2-weighted sequence (TRITE: 2,000 msl 100 ms). Transaxial view showing the presence of DWMH type A (triangle). A: in 2-year-old boy (patient 8, see Table 1) with febrile convulsion, B: in 2-year-old girl (patient 21) with epilepsy. DWMH type A means that an area which was revealed as iso- or hyperintense relative to the gray matter but hypo intense relative to CSF was disclosed in the deep white matter of the occipital lobe.
Fig 2 MRI: spin echo T2-weighted sequence (TRITE: 2,000 msl 100 ms). Transaxial view showing the presence of D WMH type B (triangle). A: in 3-year-old boy (patient 5, see Table 1) with FCMD, showing ventricualrdilatation and multifocal hyperintensity, too, B: in 6-year-old boy (patient 26) with MR. DWMH type B means that an area which was revealed as isointense relative to CSF was disclosed in the deep white matter of the occipital lobe.
Tsumori-Inage Scales or Enjyoji Scales of Infantile Development. Statistical analysis was evaluated using the X2 test. On condition that the number of subjects was under four, Yates's modification was performed.
genital muscular dystrophy (F-CMD), 1; congenital myotonic dystrophy (CMyD), 2; febrile convulsion, 2; autism, 3; epilepsy, 9; mental retardation and/or delayed motor development caused by perinatal accident (perinatal cause), 2; and mental retardation and/or delayed motor development without obvious causes including perinatal causes of the handicap (unknown cause), 4. Regarding perinatal period, five patients (patients 6, 7,15,22 and 23) suffered from the accidents including asphyxia, apnea, hypoglycemia and convulsion. Regarding the type distribution, 19 patients belonged to type A and 8 patients type B. Eight of these 27 patients presented with ventricular dilatation on MRI. Two of the 8 patients had DWMH type A and the remaining 6 patients had DWMH type B. Four of these 27 patients (patients 5, 6, 7 and 17), who all belonged to type B, presented with multiple focal hyperintensity not restricted to the occipital lobe (Table 1). Patients with F-CMD and CMyD had a higher incidence
RESULTS Twenty-seven of 270 children studied (10.0%) had DWMH on T2-weighted images. The areas were disclosed as iso- or hypointense relative to the surrounding white matter on Tl-weighted images (field echo sequence TR/TE: 300 ms/ 140 ms) and all of them were disclosed as hyperintensity relative to CSF on PD-weighted images (spin echo sequence TR/TE: 2,000 ms/30 ms). The diagnoses of these 27 patients included: medulloblastoma after multidisciplinary therapy, I; congenital heart disease (CHD), I; neurofibromatosis, 1; tuberous sclerosis, 1; Fukuyama con-
Miyazaki et al: Deep white matter hyperintensity 151
Table I Clinical features in 27 patients with DWMH
Patient
Sex
1
F
2
F
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
F
Age (yeors)
F
15 1 6 9 3 3 1
M
2
M M
7 3 3
M
7
F
6
M
7
F M M
M
M
1
M M
5 3 5 8 1 2 1 3 13 1 6 1
F M M F
22
M
23
M
24
M
25
M
26
M
27
F
MR
Diagnosis
(1)
Medulloblastoma CHD Neurofibromatosis Tuberous sclerosis F-CMD CMyD CMyD Febrile convulsion Febrile convulsion Autism Autism Autism Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Perinatal cause Perinatal cause Unknown cause Unknown cause Unknown cause Unknown cause
(2)
Type
(-)
(-)
A
(+)
(-)
B
(-)
(-)
A
(++)
(-)
A
(-)
B
(++)
(+)
a+
B
(++)
a+b+
B
(-)
(-)
A
(-)
(-)
A
(+)
(-)
A
(+)
(-)
A
(+)
(-)
A
(-)
(-)
A
(++)
(-)
B
(+)
a+c+d+
A
(-)
(-)
A
(-)
(-)
B
(+)
(-)
A
(-) (-)
(-)
(+)
(-)
(-) (-)
A
(-)
A
A
a+ a+
A A
(-)
(-)
(+)
(-)
A
(++)
(-)
B
(-)
(-)
A
B
MRI findings Ventricular T1·weighted image dilatation Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Hypointensity Hypointensity Isointensity Hypointensity Hypointensity Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Hypointensity Isointensity Hypointensity Isointensity
Multifocal hyperintensity
(-)
(-)
(+)
(-)
(-)
(-)
(-)
(-)
(+)
(+)
(+)
(+)
(+)
(+)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(+)
(-)
(+)
(-)
(-)
(-)
(+)
(+)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(+)
(-)
CHD: congenital heart disease, F-CMD: Fukuyama congenital muscular dystrophy, CMyD: congenital myotonic dystrophy, Perinatal cause: mental retardation and/or delayed motor development caused by perinatal accident, Unknown cause: mental retardation and/or delayed motor development without obvious causes. MR: mental retardation, (1) (-): IQ or DQ > 85, (+): 85;;. IQ or DQ;;. 50, (++): IQ or DQ ';;49, (2) (-): absent, a+: asphyxia, b+: apnea, c+: hypoglycemia, d+: convulsion.
Table 2 Clinical diagnoses for 27 patients with DWMH Diagnosis DWMH Type A (%)
TypeB
Medulloblastoma 1 (100)
o
CHD
o
Neurofibromatosis
Tuberous sclerosis
1
1 (25.0)
( 0.0)
(ILl)
1 (25.0)
( 0.0)
o
F-CMD
o
CMyD
o
Febrile convulsion
Autism
Epilepsy
Others
3 (12.5)
7 ( 6.9)
(/) 2 (/)
( 0.0)
( 0.0)
2 ( 8.3)
( 0.0)
1 (50.0)
2 (50.0)
( 0.0)
( 0.0)
2 ( 2.0)
22
21 (87.5)
(91.1)
(/)
102 (100)
/ (/)
o
o
o
(%)
(0.0)
(%)
(0.0)
3 (75.0)
8 (88.9)
3 (75.0)
1 (50.0)
2 (50.0)
(91.7)
Total
1 (100)
4
9 (100)
4 (100)
2 (100)
4 (100)
24
24
(100)
(100)
(100)
o
(%)
4
/
93
Data are expressed as the numbers of cases. Type A+, Type B+ and - mean the presence of DWMH type A, type B and the absence of DWMH, respectively. The percentage to each total number of cases is given in parenthesis.
152 Brain & Development, Vol 14, No 3, 1992
Table 3 The relation between age and frequency
Table 4 The relation between DQ or IQ and frequency ofDWMH
ofDWMH
Age (years)
1-3
4-6
7-9
10-12 13-15
Total
DWMH
DWMH Type A+ (%)
10 (11.5)
440 (5.4) (9.8) (0.0)
1 (3.1)
-----9-----
DQor IQ
19 (7.0)
Type A+
8 (3.0)
Type B+
>85
85-70 69-50 49-35
11 (8.4)
3 (6.1)
(%)
18 (7.8)
(4.9)* TypeB+ (%)
5 ( 5.7)
101 1 (1.4) (2.4) (0.0) (3.1) -----3-----
2 (1.5)
(%)
Total
1 (2.0)
1 (2.0)
72
69 (93.2)
36 (87.8)
36 (100)
30 (93.8)
243 (90.0)
87
74
41
36
32
270
(%)
Total
118 (90.1)
131
45 46 (91.9) (90.2) 49
1 (7.7)
2 2 (7.7) (15.4) 4 (10.5)*
(1.7)
(82.8)
0 (0.0)
1 ( 2.6)
4
(1.6) (%)
4 (7.8)
Magnetic resonance imaging was performed in 270 patients with various neurologic complaints (1-15Y) with a 0.5 tesla superconducting imaging system using a field echo Tl-weighted sequence and spin echo T2-weighted and PD-weighted sequences. Twenty-seven of them had deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images. The frequency of mild DWMH differed in different age groups, suggesting that mild DWMH may result from delayed myelination in the central nervous system. However, the frequency of severe DWMH, which was revealed as isointense relative to cerebrospinal fluid, did not differ in different age groups and it was significantly more common in severely retarded patients. Classification of DWMH based on the signal intensity is valuable to distinguish white matter abnormalities in the occipital lobe from delayed myelination in the same site. Key words: MRI, T2-weighted image, deep white matter hyperintensity, mental retardation. Miyazaki M, Hashimoto T, Tayama M, Kuroda Y. Occipital deep white matter hyperintensity as seen by MRI: 1. clinical significance. Brain Dev 1992;14:150-5
Magnetic resonance imaging (MRI) allows a detailed examination of lesions in the white matter that include demyelination in the central nervous system. Information regarding clinical characteristics of lesions with a hyperintensity disclosed by a T2-weighted image in the periventricle and/or deep white matter has been accumulated mostly in adult patients (1-9]. Although a few reports exist concerning the pediatric population, the pathological significance of these lesions remains almost unknown. In this report, we have studied the clinical characteristics of children who were found to have deep white matter hyperintensity (DWMH) in the occipital lobe on T2-weighted images and tried to determine the difference between delayed myelination in the OCCipital white matter versus abnormalities, e.g. pathologic demyelination, in the same location.
From the Department of Pediatrics, School of Medicine, University of Tokushima, Tokushima Received for publication: January 11, 1992. Accepted for publication : March 9, 1992. Correspondence address: Dr. Masahito Miyazaki, Department of Brain Pathophysiology, Faculty of Medicine, Kyoto University, Shogoin-Kawaharamachi, Sakyo, Kyoto 606, Japan.
PATIENTS AND METHODS Two hundred and seventy patients who visited our hospital with various neurological complaints underwent MRI examination. The patients' age ranged from 1 to 15 years (mean 6.3 years). An MRI examination was performed with a 0.5 tesla superconducting imaging system (MRT50A, Toshiba Co) using a field echo sequence (TR/TE: 300 ms/14 ms) and spin echo sequences (TR/TE: 2,000 ms/ I 00 ms or 2,000 ms/ 120 ms, and 2,000 ms/30 ms). The thickness of each slice was 10 mm. DWMH was evaluated by a T2-weighted transaxial image (spin echo sequence TR/TE: 2,000 ms/IOO ms or 2,000 ms/120 ms) through the horizontal level of the body of the lateral ventricle or foramen of Monro, based on visual impression. DWMH type A was diagnosed when an area which was revealed as iso- or hyperintense relative to the gray matter but hypointense relative to cerebrospinal fluid (CSF) was disclosed in the deep white matter of the occipital lobe. DWMH type B was diagnosed when an area which was revealed as isointense relative to CSF was disclosed there (Figs 1, 2) [4,5]. All patients were neuropsychologically investigated to assess mental and motor function with intelligence quotient (IQ) or developmental quotient (DQ). IQ was evaluated using WISC-R and DQ was evaluated using
Fig 1 MRI: spin echo T2-weighted sequence (TRITE: 2,000 msl 100 ms). Transaxial view showing the presence of DWMH type A (triangle). A: in 2-year-old boy (patient 8, see Table 1) with febrile convulsion, B: in 2-year-old girl (patient 21) with epilepsy. DWMH type A means that an area which was revealed as iso- or hyperintense relative to the gray matter but hypo intense relative to CSF was disclosed in the deep white matter of the occipital lobe.
Fig 2 MRI: spin echo T2-weighted sequence (TRITE: 2,000 msl 100 ms). Transaxial view showing the presence of D WMH type B (triangle). A: in 3-year-old boy (patient 5, see Table 1) with FCMD, showing ventricualrdilatation and multifocal hyperintensity, too, B: in 6-year-old boy (patient 26) with MR. DWMH type B means that an area which was revealed as isointense relative to CSF was disclosed in the deep white matter of the occipital lobe.
Tsumori-Inage Scales or Enjyoji Scales of Infantile Development. Statistical analysis was evaluated using the X2 test. On condition that the number of subjects was under four, Yates's modification was performed.
genital muscular dystrophy (F-CMD), 1; congenital myotonic dystrophy (CMyD), 2; febrile convulsion, 2; autism, 3; epilepsy, 9; mental retardation and/or delayed motor development caused by perinatal accident (perinatal cause), 2; and mental retardation and/or delayed motor development without obvious causes including perinatal causes of the handicap (unknown cause), 4. Regarding perinatal period, five patients (patients 6, 7,15,22 and 23) suffered from the accidents including asphyxia, apnea, hypoglycemia and convulsion. Regarding the type distribution, 19 patients belonged to type A and 8 patients type B. Eight of these 27 patients presented with ventricular dilatation on MRI. Two of the 8 patients had DWMH type A and the remaining 6 patients had DWMH type B. Four of these 27 patients (patients 5, 6, 7 and 17), who all belonged to type B, presented with multiple focal hyperintensity not restricted to the occipital lobe (Table 1). Patients with F-CMD and CMyD had a higher incidence
RESULTS Twenty-seven of 270 children studied (10.0%) had DWMH on T2-weighted images. The areas were disclosed as iso- or hypointense relative to the surrounding white matter on Tl-weighted images (field echo sequence TR/TE: 300 ms/ 140 ms) and all of them were disclosed as hyperintensity relative to CSF on PD-weighted images (spin echo sequence TR/TE: 2,000 ms/30 ms). The diagnoses of these 27 patients included: medulloblastoma after multidisciplinary therapy, I; congenital heart disease (CHD), I; neurofibromatosis, 1; tuberous sclerosis, 1; Fukuyama con-
Miyazaki et al: Deep white matter hyperintensity 151
Table I Clinical features in 27 patients with DWMH
Patient
Sex
1
F
2
F
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
F
Age (yeors)
F
15 1 6 9 3 3 1
M
2
M M
7 3 3
M
7
F
6
M
7
F M M
M
M
1
M M
5 3 5 8 1 2 1 3 13 1 6 1
F M M F
22
M
23
M
24
M
25
M
26
M
27
F
MR
Diagnosis
(1)
Medulloblastoma CHD Neurofibromatosis Tuberous sclerosis F-CMD CMyD CMyD Febrile convulsion Febrile convulsion Autism Autism Autism Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Epilepsy Perinatal cause Perinatal cause Unknown cause Unknown cause Unknown cause Unknown cause
(2)
Type
(-)
(-)
A
(+)
(-)
B
(-)
(-)
A
(++)
(-)
A
(-)
B
(++)
(+)
a+
B
(++)
a+b+
B
(-)
(-)
A
(-)
(-)
A
(+)
(-)
A
(+)
(-)
A
(+)
(-)
A
(-)
(-)
A
(++)
(-)
B
(+)
a+c+d+
A
(-)
(-)
A
(-)
(-)
B
(+)
(-)
A
(-) (-)
(-)
(+)
(-)
(-) (-)
A
(-)
A
A
a+ a+
A A
(-)
(-)
(+)
(-)
A
(++)
(-)
B
(-)
(-)
A
B
MRI findings Ventricular T1·weighted image dilatation Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Hypointensity Hypointensity Isointensity Hypointensity Hypointensity Isointensity Isointensity Isointensity Isointensity Hypointensity Hypointensity Hypointensity Isointensity Hypointensity Isointensity
Multifocal hyperintensity
(-)
(-)
(+)
(-)
(-)
(-)
(-)
(-)
(+)
(+)
(+)
(+)
(+)
(+)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(+)
(-)
(+)
(-)
(-)
(-)
(+)
(+)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(-)
(+)
(-)
CHD: congenital heart disease, F-CMD: Fukuyama congenital muscular dystrophy, CMyD: congenital myotonic dystrophy, Perinatal cause: mental retardation and/or delayed motor development caused by perinatal accident, Unknown cause: mental retardation and/or delayed motor development without obvious causes. MR: mental retardation, (1) (-): IQ or DQ > 85, (+): 85;;. IQ or DQ;;. 50, (++): IQ or DQ ';;49, (2) (-): absent, a+: asphyxia, b+: apnea, c+: hypoglycemia, d+: convulsion.
Table 2 Clinical diagnoses for 27 patients with DWMH Diagnosis DWMH Type A (%)
TypeB
Medulloblastoma 1 (100)
o
CHD
o
Neurofibromatosis
Tuberous sclerosis
1
1 (25.0)
( 0.0)
(ILl)
1 (25.0)
( 0.0)
o
F-CMD
o
CMyD
o
Febrile convulsion
Autism
Epilepsy
Others
3 (12.5)
7 ( 6.9)
(/) 2 (/)
( 0.0)
( 0.0)
2 ( 8.3)
( 0.0)
1 (50.0)
2 (50.0)
( 0.0)
( 0.0)
2 ( 2.0)
22
21 (87.5)
(91.1)
(/)
102 (100)
/ (/)
o
o
o
(%)
(0.0)
(%)
(0.0)
3 (75.0)
8 (88.9)
3 (75.0)
1 (50.0)
2 (50.0)
(91.7)
Total
1 (100)
4
9 (100)
4 (100)
2 (100)
4 (100)
24
24
(100)
(100)
(100)
o
(%)
4
/
93
Data are expressed as the numbers of cases. Type A+, Type B+ and - mean the presence of DWMH type A, type B and the absence of DWMH, respectively. The percentage to each total number of cases is given in parenthesis.
152 Brain & Development, Vol 14, No 3, 1992
Table 3 The relation between age and frequency
Table 4 The relation between DQ or IQ and frequency ofDWMH
ofDWMH
Age (years)
1-3
4-6
7-9
10-12 13-15
Total
DWMH
DWMH Type A+ (%)
10 (11.5)
440 (5.4) (9.8) (0.0)
1 (3.1)
-----9-----
DQor IQ
19 (7.0)
Type A+
8 (3.0)
Type B+
>85
85-70 69-50 49-35
11 (8.4)
3 (6.1)
(%)
18 (7.8)
(4.9)* TypeB+ (%)
5 ( 5.7)
101 1 (1.4) (2.4) (0.0) (3.1) -----3-----
2 (1.5)
(%)
Total
1 (2.0)
1 (2.0)
72
69 (93.2)
36 (87.8)
36 (100)
30 (93.8)
243 (90.0)
87
74
41
36
32
270
(%)
Total
118 (90.1)
131
45 46 (91.9) (90.2) 49
1 (7.7)
2 2 (7.7) (15.4) 4 (10.5)*
(1.7)
(82.8)
0 (0.0)
1 ( 2.6)
4
(1.6) (%)
4 (7.8)
