[Diagnostic efficacy of prostate cancer using targeted biopsy with 6-core systematic biopsy for patients with PI-RADS 5].

OBJECTIVE: To investigate the diagnostic efficacy of targeted biopsy (TBx), systematic biopsy (SBx), TBx+6-core SBx in prostate cancer (PCa) / clinically significant prostate cancer (cs-PCa) for patients with prostate imaging reporting and data system (PI-RADS) score of 5, and thereby to explore an optimal sampling scheme. METHODS: The data of 585 patients who underwent multiparametric magnetic resonance imaging (mpMRI) with at least one lesion of PI-RADS score 5 at Peking University First Hospital from January 2019 to June 2022 were retrospectively analyzed. All patients underwent mpMRI / transrectal ultrasound (TRUS) cognitive guided biopsy (TBx+SBx). With the pathological results of combined biopsy as the gold standard, we compared the diagnostic efficacy of TBx only, SBx only, and TBx+6-core SBx for PCa/csPCa. The patients were grouped according to mpMRI T-stage (cT2, cT3, cT4) and the detection rates of different biopsy schemes for PCa/csPCa were compared using Cochran's Q and McNemar tests. RESULTS: Among 585 patients with a PI-RADS score of 5, 560 (95.7%) were positive and 25(4.3%) were negative via TBx+SBx. After stratified according to mpMRI T-stage, 233 patients (39.8%) were found in cT2 stage, 214 patients (36.6%) in cT3 stage, and 138 patients (23.6%) in cT4 stage. There was no statistically significant difference in the detection rate of PCa/csPCa between TBx+6-core SBx and TBx+SBx (all P>0.999). Also, there was no statistically significant difference in the detection rate of PCa/csPCa between TBx and TBx+SBx in the cT2, cT3, and cT4 subgroups (PCa: P=0.203, P=0.250, P>0.999; csPCa: P=0.700, P=0.250, P>0.999). The missed diagnosis rate of SBx for PCa and csPCa was 2.1% (12/560) and 1.8% (10/549), and that of TBx for PCa and csPCa was 1.8% (10/560) and 1.4% (8/549), respectively. However, the detection rate of TBx+6-core SBx for PCa and csPCa was 100%. Compared with TBx+SBx, TBx and TBx+6-core SBx had a fewer number of cores and a higher detection rate per core (P < 0.001). CONCLUSION: For patients with a PI-RADS score of 5, TBx and TBx+6-core SBx showed the same PCa/csPCa detection rates and a high detection rates per core as that of TBx+SBx, which can be considered as an optimal scheme for prostate biopsy.

Identification in Chinese patients with GLIALCAM mutations of megalencephalic leukoencephalopathy with subcortical cysts and brain pathological study on Glialcam knock-in mouse models.

BACKGROUND: Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare neurological degenerative disorder caused by the mutations of MLC1 or GLIALCAM with autosomal recessive or autosomal dominant inheritance and a different prognosis, characterized by macrocephaly, delayed motor and cognitive development, and bilateral abnormal signals in cerebral white matter (WM) with or without cysts on magnetic resonance imaging (MRI). This study aimed to reveal the clinical and genetic features of MLC patients with GLIALCAM mutations and to explore the brain pathological characteristics and prognosis of mouse models with different modes of inheritance. METHODS: Clinical information and peripheral venous blood were collected from six families. Genetic analysis was performed by Sanger sequencing of GLIALCAM. GlialcamArg92Trp/+ and GlialcamLys68Met/Thr132Asn mouse models were generated based on mutations from patients (c.274C>T(p.Arg92Trp) (c.203A>T(p.Lys68Met), and c.395C>A (p.Thr132Asn))). Brain pathologies of the mouse models at different time points were analyzed. RESULTS: Six patients were clinically diagnosed with MLC. Of the six patients, five (Pt1-Pt5) presented with a heterozygous mutation in GLIALCAM (c.274C>T(p.Arg92Trp) or c.275G>C(p.Arg92Pro)) and were diagnosed with MLC2B; the remaining patient (Pt6) with two compound heterozygous mutations in GLIALCAM (c.203A>T (p.Lys68Met) and c.395C>A (p.Thr132Asn)) was diagnosed with MLC2A. The mutation c.275C>G (p.Arg92Pro) has not been reported before. Clinical manifestations of the patient with MLC2A (Pt6) progressed with regression, whereas the course of the five MLC2B patients remained stable or improved. The GlialcamArg92Trp/+ and GlialcamLys68Met/ Thr132Asn mouse models showed vacuolization in the anterior commissural WM at 1 month of age and vacuolization in the cerebellar WM at 3 and 6 months, respectively. At 9 months, the vacuolization of the GlialcamLys68Met/ Thr132Asn mouse model was heavier than that of the GlialcamArg92Trp/+ mouse model. Decreased expression of Glialcam in GlialcamArg92Trp/+ and GlialcamLys68Met/ Thr132Asn mice may contribute to the vacuolization. CONCLUSIONS: Clinical and genetic characterization of patients with MLC and GLIALCAM mutations revealed a novel mutation, expanding the spectrum of GLIALCAM mutations. The first Glialcam mouse model with autosomal recessive inheritance and a new Glialcam mouse model with autosomal dominant inheritance were generated. The two mouse models with different modes of inheritance showed different degrees of brain pathological features, which were consistent with the patients' phenotype and further confirmed the pathogenicity of the corresponding mutations.

T2 Mapping and Fat Quantification of Thigh Muscles in Children with Duchenne Muscular Dystrophy.

Quantitative magnetic resonance image (MRI) in individual muscles may be useful for monitoring disease progression in Duchenne muscular dystrophy (DMD). The purpose of this study was to measure T2 relaxation time of thigh muscles in children with DMD and healthy boys, and to correlate the T2 relaxation time of muscles with the fat fraction (FF) at quantitative magnetic resonance and results of clinical assessment. Thirty-two boys with DMD and 18 healthy boys were evaluated with T2 mapping and three-point Dixon MRI. Age, body mass index (BMI), muscle strength assessment, timed functional tests (time to walk or run 10 metres, rise from the floor and ascend four stairs), and the North Star Ambulatory Assessment (NSAA) were evaluated. Spearman's correlation was used to assess the relationships between FF and clinical assessments and T2 relaxation time. The mean T2 relaxation time of thigh muscles in DMD was significantly longer than that in the control group (P<0.05), except for the gracilis (P=0.952). The gracilis, sartorius and adductor longus were relatively spared by fatty infiltration in DMD patients. The T2 relaxation time was correlated significantly with the mean FF in all muscles. Age, BMI, total muscle strength score, timed functional tests and NSAA were significantly correlated with the overall mean T2 relaxation time. T2 mapping may prove clinically useful in monitoring muscle changes as a result of the disease process and in predicting the outcome of DMD patients.

Muscle Magnetic Resonance Imaging in Patients with Various Clinical Subtypes of LMNA-Related Muscular Dystrophy.

BACKGROUND: LMNA-related muscular dystrophy can manifest in a wide variety of disorders, including Emery-Dreifuss muscular dystrophy (EDMD), limb-girdle muscular dystrophy (LGMD), and LMNA-associated congenital muscular dystrophy (L-CMD). Muscle magnetic resonance imaging (MRI) has become a useful tool in the diagnostic workup of patients with muscle dystrophies. This study aimed to investigate whether there is a consistent pattern of MRI changes in patients with LMNA mutations in various muscle subtypes. METHODS: Twenty-two patients with LMNA-related muscular dystrophies were enrolled in this study. MRI of the thigh and/or calf muscles was performed in them. The muscle MRI features of the three subtypes were compared by the Mann-Whitney U-test. The relationship between the clinical and MRI findings was also investigated by Spearman's rank analyses. RESULTS: The present study included five EDMD, nine LGMD, and eight L-CMD patients. The thigh muscle MRI revealed that the fatty infiltration of the adductor magnus, semimembranosus, long and short heads of the biceps femoris, and vasti muscles, with relative sparing of the rectus femoris, was the predominant change observed in the EDMD, LGMD, and advanced-stage L-CMD phenotypes, although the involvement of the vasti muscles was not prominent in the early stage of L-CMD. At the level of the calf, six patients (one EDMD, four LGMD, and one L-CMD) also showed a similar pattern, in which the soleus and the medial and lateral gastrocnemius muscles were most frequently observed to have fatty infiltration. The fatty infiltration severity demonstrated higher scores associated with disease progression, with a corresponding rate of 1.483 + 0.075 × disease duration (X) (r = 0.444, P = 0.026). It was noteworthy that in six L-CMD patients with massive inflammatory cell infiltration in muscle pathology, no remarkable edema-like signals were observed in muscle MRI. CONCLUSIONS: EDMD, LGMD and advanced-staged L-CMD subtypes showed similar pattern of muscle MRI changes, while early-staged L-CMD showed somewhat different changes. Muscle MRI of L-CMD with a muscular dystrophy pattern in MRI provided important clues for differentiating it from childhood inflammatory myopathy. The fatty infiltration score could be used as a reliable biomarker for outcome measure of disease progression.

3.0 T magnetic resonance myocardial perfusion imaging for semi-quantitative evaluation of coronary microvascular dysfunction in hypertrophic cardiomyopathy.

This study aimed to assess coronary microvascular dysfunction (CMD) differences in hypertrophic cardiomyopathy (HCM) patients using cardiac magnetic resonance (CMR) first-pass perfusion and late gadolinium enhancement imaging. Forty-seven patients with HCM and twenty-one healthy volunteers underwent CMR at rest. Imaging protocols included short axis cine, first-pass myocardial perfusion, and late gadolinium enhancement (LGE). Left ventricular end-diastolic wall thickness (EDTH), LGE, time to peak (Tpeak), maximal up-slope (Slopemax), and peak signal intensity (SIpeak) were assessed for each myocardial segment. The HCM myocardial segments were grouped by the degree of LGE and hypertrophy. Tpeak, SIpeak, Slopemax and EDTH in multiple groups were assessed and compared by ANOVA test/Kruskal-Wallis test. The Spearman correlation test was used to determine the relationships between EDTH, LGE and perfusion parameters (Tpeak, Slopemax and SIpeak). Compared to control group segments, Tpeak increased while Slopemax and SIpeak decreased in non-LGE/non-hypertrophic segments and LGE/hypertrophic segments in the HCM group, while Tpeak increased more significantly in LGE/hypertrophic segments (all p < 0.05). Tpeak statistically increased with increasing degrees of myocardial LGE (p < 0.01). Differences in Tpeak, SIpeak and EDTH were observed between segments with and without hypertrophy (p < 0.05). EDTH and LGE were positively correlated with Tpeak (r = 0.279, p = 0.031 and r = 0.237, p < 0.001). 3.0 T magnetic resonance myocardial perfusion imaging identifies abnormal perfusion in non-LGE and non-hypertrophic segments of HCM patients, and it may be helpful in the early diagnosis of coronary microvascular dysfunction in HCM. This abnormal perfusion is associated with the severity of myocardial fibrosis and the degree of hypertrophy.

Determination of oxygen extraction fraction using magnetic resonance imaging in canine models with internal carotid artery occlusion.

Perfusion of the penumbra tissue below the flow threshold for functional disturbance but above that for the maintenance of morphological integrity is the target for therapy in acute ischaemic stroke. The measurement of the oxygen extraction fraction (OEF) may provide a direct assessment of tissue viability, so that irreversible tissue damage and penumbra can be reliably identified. By using an asymmetric spin echo single-shot echo planar imaging (ASE-SSEPI) sequence, the quantitative OEF was obtained in the ischaemic brain tissues of canine models with internal carotid artery occlusion. TTC staining, which delineated the regions of infarct and penumbra, was used for defining the corresponding regions on OEF maps. The threshold of the OEF to discriminate the infarct cores and penumbral tissues was then determined according to the OEF values at different times. With repeated-measures ANOVA, the OEF of the infarcted regions was found to be time dependent. An OEF greater than 0.48 best predicted cortical infarction at 1.5 hr, with an area under the receiving operating characteristic curve of 0.968, a sensitivity of 97.5%, and a specificity of 92.5%. Our results may be helpful in the evaluation of tissue viability during stroke events.

"Target" and "Sandwich" Signs in Thigh Muscles have High Diagnostic Values for Collagen VI-related Myopathies.

BACKGROUND: Collagen VI-related myopathies are autosomal dominant and recessive hereditary myopathies, mainly including Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM). Muscle magnetic resonance imaging (MRI) has been widely used to diagnosis muscular disorders. The purpose of this study was to evaluate the diagnostic value of thigh muscles MRI for collagen VI-related myopathies. METHODS: Eleven patients with collagen VI gene mutation-related myopathies were enrolled in this study. MRI of the thigh muscles was performed in all patients with collagen VI gene mutation-related myopathies and in 361 patients with other neuromuscular disorders (disease controls). T1-weighted images were used to assess fatty infiltration of the muscles using a modified Mercuri's scale. We assessed the sensitivity and specificity of the MRI features of collagen VI-related myopathies. The relationship between fatty infiltration of muscles and specific collagen VI gene mutations was also investigated. RESULTS: Eleven patients with collagen VI gene mutation-related myopathies included six UCMD patients and five BM patients. There was no significant difference between UCMD and BM patients in the fatty infiltration of each thigh muscle except sartorius (P = 0.033); therefore, we combined the UCMD and BM data. Mean fatty infiltration scores were 3.1 and 3.0 in adductor magnus and gluteus maximus, while the scores were 1.3, 1.3, and 1.5 in gracilis, adductor longus, and sartorius, respectively. A "target" sign in rectus femoris (RF) was present in seven cases, and a "sandwich" sign in vastus lateralis (VL) was present in ten cases. The "target" and "sandwich" signs had sensitivities of 63.6% and 90.9% and specificities of 97.3% and 96.9% for the diagnosis of collagen VI-related myopathies, respectively. Fatty infiltration scores were 2.0-3.0 in seven patients with mutations in the triple-helical domain, and 1.0-1.5 in three of four patients with mutations in the N- or C-domain of the collagen VI genes. CONCLUSIONS: The "target" sign in RF and "sandwich" sign in VL are common MRI features and are useful for the diagnosis of collagen VI-related myopathies. The severity of fatty infiltration of muscles may have a relationship with the mutation location of collagen VI gene.

Clinical and Brain Magnetic Resonance Imaging Features in a Cohort of Chinese Patients with Kearns-Sayre Syndrome.

BACKGROUND: Kearns-Sayre syndrome (KSS) is a mitochondrial DNA (mtDNA) deletion disorder characterized by a triad of onset before 20 years of age, ophthalmoplegia, and pigmentary retinopathy. The heart and central nervous system are commonly involved. We summarized clinical and brain magnetic resonance imaging (MRI) features of a cohort of Chinese KSS patients. METHODS: Nineteen patients confirmed by muscle biopsy and mtDNA analysis were enrolled. We examined clinical profiles, mainly focusing on changes in electrocardiogram (ECG) and brain MRI. The correlation between genotype and phenotype was statistically analyzed. RESULTS: The mean age of onset was 9.6 ± 4.3 years, with all developing the classic triad at the time of diagnosis. Heart conduction block was detected in 63.2%, with four initially presenting as bundle branch block and developing into complete atrioventricular block over 3-72 months. Brain MRI showed symmetric high-T2 signals in 100% of cerebral and cerebellar white matter, as well as brainstem, 46.7% of basal ganglia, and 53.3% of thalamus. There were two patterns of cerebral white matter involvements, one with selective subcortical U-fibers and the other with periventricular white matter. The size of mtDNA deletion did not significantly correlate with age of onset or percentage of ragged blue fibers on muscle pathology. CONCLUSIONS: The clinical features of KSS evolve dynamically, affecting the cardiac conduction system predominantly, highlighting the significance of ECG monitoring. Brain MRI showed changes involving both the white matter and deep gray nuclei. Clinical presentation or severity of muscle pathological changes is not related to the size of mtDNA deletions.

[Mitochondrial respiratory chain complex I deficiency due to 10191T>C mutation in ND3 gene].

This study reviews a case of mitochondrial respiratory chain complex I deficiency due to the 10191T>C mutation in mitochondrial ND3 gene. The previously healthy boy progressively presented with blepharoptosis, weakness, epilepsy and motor regression at age 6 years. Elevated blood lactate and pyruvate were observed. Brain magnetic resonance imaging showed symmetrical lesions in the basal ganglia. Leigh syndrome was thus confirmed. The protein from the mitochondria and genomic DNA of the boy and his parents was collected from peripheral blood leucocytes for the activity test for mitochondrial complex I to V and genetic analysis. The results showed the activity of complex I (33.1 nmol /min in 1 milligram mitochondrial protein) was lower than normal reference value (44.0±5.4 nmol /min in 1 milligram mitochondrial protein). The ratio of complex I to citrate synthase (19.8%) was also lower than normal reference value (48%±11%). The activities of complexes II to V were normal. 10191T>C mutation in ND3 gene of mitochondria was identified in the boy. 10191T>C mutation and complex I deficiency were not detected in his parents. At present, he is 16 years old, and of normal intelligence with spastic paralysis in both lower extremities after treatment. It is concluded that a Chinese boy with isolated complex I deficiency due to 10191T>C mutation in ND3 gene was firstly diagnosed by peripheral leukocytes mitochondrial respiratory chain enzyme assay and gene analysis. This study can provide clinical data for the nosogenesis of Leigh syndrome.

[Clinical and genetic study of twelve Chinese patients with Alexander disease].

OBJECTIVE: To delineate the phenotype and genotype characteristics in 12 Chinese children with Alexander disease (AD), which is helpful for the molecular diagnosis and genetic counseling in China. METHODS: Clinical diagnosis of AD was based on MRI criteria proposed by van der Knaarp in 2001. Included AD patients were followed up for 0.50 - 3.67 years. Mutations in GFAP were detected by DNA sequencing. RESULTS: The 12 cases of AD were clinically diagnosed. Age of first visit was 4.87 years (0.75 - 12.00 years), with 3 types of chief complaints: developmental delay in 3, recurrent seizures in 7, unable to walk after falling in 2. Average head circumference was 52.34 cm (44 - 58 cm), which larger than age-matched average by 6.45% (1.80% - 13.95%). On the first visit, scaling according to Gross motor functional classification system (GMFCS) was performed, with GMFCSI in 8, II in 3, V in 1. Mild to severe cognitive dysfunction were found in 8, and seizures in 11 cases. The 12 patients were followed up for 0.50 - 3.67 years, their motor and cognitive function remained stable. Episodic aggravations provoked by fever or falling were observed in 5 cases (41.67%). Heterozygous missense mutations of GFAP were detected in 12 patients. All mutations were de novo; 3 out of 10 mutations identified were novel. R79 and R239 were hot mutations, which was consistent with previous reports. Mutations were located in exon 1 in 8 cases. CONCLUSIONS: The phenotype in these patients is characterized by slower progression compared with reports from other population and high incidence of seizures. And episodic aggravations provoked by fever or falling were more common. The genotype characteristics are consistent with previous reports. The results of this research expanded the number of patients with Alexander disease found to have GFAP coding mutations in China.

[Clinical and genetic analysis of a family with leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation].

OBJECTIVE: Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) is a rare autosomal recessive disease. Affected individuals are invariably compound heterozygous for two mutations in DARS2. No reports of LBSL patients have been published in the mainland of China. The aim of this study was to explore the clinical and genetic features of a family with LBSL, which may contribute to definite diagnosis, genetic counseling and prenatal diagnosis of this rare disease in China. METHODS: Clinical data of the proband and other family members as well as DNA samples were collected. Clinical features including symptoms, signs and cranial MRI were analyzed. All 17 exons and exon-intron boundaries of DARS2 gene were amplified with polymerase chain reaction (PCR) and directly sequenced for genomic DNA. The mutation was proved by DNA restriction enzyme digestion of PCR-amplified fragments. RESULTS: (1) The clinical features of patient with LBSL included slowly progressive cerebellar ataxia and spasticity, the neurologic dysfunction involving the legs more than the arms, and with characteristic abnormalities observed on brain and spinal cord MRI. (2) Two mutations were identified, one was a novel missense mutation [c.665 G > A(p.Gly222Asp)] in DARS2 gene exon 8, the other (c.228-16 C > G) was in DARS2 gene intron 3. CONCLUSION: This is the first report on LBSL patient and DARS2 mutation in China. p.Gly222Asp mutation is a novel mutation not reported around the world yet.

[Leigh syndrome due to mitochondrial respiratory chain complex II deficiency].

Mitochondrial respiratory chain complex II deficiency is a rare documented cause of mitochondrial diseases. This study reported a case of Leigh syndrome due to isolated complex II deficiency. A boy presented with progressive weakness, motor regression and dysphagia after fever from the age of 8 months and hospitalized at the age of 10 months. Elevated blood levels of lactate and pyruvate were observed. Brain magnetic resonance image showed symmetrical lesions in the basal ganglia. Mitochondrial respiratory chain complex I-V activities in peripheral leukocytes were measured using spectrophotometric assay. Mitochondrial gene screening of common point mutations was performed. The complex II activity in the peripheral leukocytes decreased to 21.9 nmol/min per mg mitochondrial protein (control: 47.3±5.3 nmol/min per mg mitochondrial protein). The ratio of complex II activity to citrate synthase activity (22.1%) also decreased (control: 50.9%±10.7 %). No point mutation was found in mitochondrial DNA. The boy was diagnosed as Leigh syndrome due to isolated complex II deficiency. Psychomotor improvements were observed after the treatment. The patient is 22 months old and in a stable condition.

[Leucodystrophy induced by late onset 3-hydroxy-3-methylglutaric aciduria].

3-Hydroxy-3-methylglutaric aciduria is a rare disorder of organic acid metabolism caused by 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency. The disorder was common in neonatal or infant period. Here a case of late onset 3-hydroxy-3-methylglutaric aciduria complicated by leucodystrophy was reported. The patient was a 7-year-old boy. He presented with progressive headache, drowsiness and vomiting. Hepatic lesions, ketosis and leucopenia were found. Symmetrical diffused leucodystrophy was shown by MRI. Blood levels of isovalerylcarnitine and acetylcarnitine increased significantly. Urinary levels of 3-hydroxy-3-methylglutaric, 3-methylglutaconic, 3-hydroxyglutaric acids and 3-methyl-crotonylglycine increased significantly. Symptoms were released by intravenous infusion of L-carnitine and glucose. After treatment for 6 months, urinary levels of 3-hydroxy-3-methylglutaric aciduria decreased in the boy and his health improved.

[Enzyme analysis of isolated mitochondrial respiratory chain complex III deficiency].

OBJECTIVE: To study the clinical and enzymological characteristics of the children with mitochondrial respiratory chain complex III deficiency. METHOD: The clinical manifestations of five patients (3 males, 2 females) were summarized. Spectrophotometric assay was used for the analysis of respiratory chain complex I to V enzyme activity in peripheral blood leukocytes, after obtaining venous blood. RESULT: (1) Five patients were hospitalized at the age of 1 month to 15 years. Three patients had Leigh syndrome with progressive motor developmental delay or regression and weakness. One had severe liver damage and intrahepatic cholestasis. One presented muscle weakness. (2) Deficient complex I + III activity was identified in five patients. Their complex I + III activities in peripheral blood leukocytes were 3.0 to 14.2 nmol/min per mg mitochondrial protein (control: 84.4 ± 28.5 nmol/min per mg mitochondrial protein). The ratio of complex I + III to citrate synthase decreased to 3.5 to 22.9% (normal control 66.1 ± 14.7%). The activities of complex III decreased to 10.4 to 49.3% of the lowest control value, while complex I, II, IV and V activities were normal. The results supported the diagnosis of isolated respiratory chain complex III deficiency. CONCLUSION: Complex III deficiency is a kind of disorder of energy metabolism with various manifestations. The complex I + III activities and the ratio of complex I + III to citrate synthase were lower than those of the control. The activities of complex I, II, IV and V were normal.

[A case of Leigh syndrome associated with respiratory chain complex I deficiency due to mitochondrial gene 13513G>A mutation].

Leigh syndrome is a genetically heterogeneous disease caused by defects in enzymes involved in aerobic energy metabolism and the Krebs', cycle. Mitonchondrial complex I deficiency is a main cause of Leigh syndrome. In this study, a Chinese child with Leigh syndrome caused by 13513G>A mutation was reported. The proband was the first child of his parents. The previously healthy boy presented with generalized epilepsy at 12 years of age. When he visited Peking University First Hospital at 13 years of age, he had subacute loss of vision in two eyes and temporal defect of visual field in the left eye. He walked with a spastic gait. His blood lactate and pyruvate levels were elevated. Muscle biopsy showed mild lipid accumulation in muscle fiber. An electrocardiogram showed incomplete right bundle branch block. Brain magnetic resonance imaging showed bilateral, symmetrical lesions in the basal ganglia, supporting the diagnosis of Leigh syndrome. 13513G>A mutation was identified by gene analysis in the patient, which led to mitochondrial respiratory chain complex I deficiency. Multivitamins and L-carnitine were administered. At present, the patient is 16 years old and has progressive deterioration with significant muscle weakness and body weight loss. He is absent from school. He has no obvious retardation in intelligence. 13513G>A mutation was first identified by gene analysis in Chinese population with Leigh syndrome. This may be helpful in genetic counseling.

Heterogeneity of magnetic resonance imaging in Leigh syndrome with SURF1 gene 604G-->C mutation.

OBJECTIVE: To identify the magnetic resonance (MR) features of a group of pediatric patients with Leigh syndrome (LS) caused by SURF1 gene 604G-->C mutation. MATERIALS AND METHODS: Eight cases with definite diagnosis of SURF1 gene 604G-->C mutation in our hospital were reviewed. Most cases presented typical symptoms in their infancy or childhood, with psychomotor regression, hypotonia, or eye movement disturbances. They all underwent cranial MR examinations after the onset. Their brain images were reviewed by an experienced neuroradiologist to determine the abnormalities. RESULTS: The data of our group showed heterogeneous neuroradiological findings: involvement of the brain stem and subthalamic nuclei was found in only three cases; basal ganglia abnormalities were detected in two cases, whereas demyelination was demonstrated in four cases; and brain atrophy existed invariably in the group. CONCLUSION: The MR presentation in LS patients with SURF1 gene 604G-->C mutation is variable. Maybe it is not appropriate to correlate a specific gene mutation with a homogenous radiological pattern.

[Leigh syndrome due to pyruvate dehydrogenase E1 alpha subunit gene mutation: a complicated and difficult case study].

Leigh syndrome is a genetically heterogeneous disease caused by defects in enzymes involved in aerobic energy metabolism and the Krebs' cycle. Deficiency of pyruvate dehydrogenase complex E1 alpha subunit (PDHA1) is the common cause of Leigh syndrome. In this study, one Chinese case of PDHA1 deficiency was reported. The patient was a boy with normal mental development, retarded motor development, general weakness, hypotonia and areflexia. Muscle histopathological findings suggested axonal peripheral neuropathy. Brain magnetic resonance imaging at 5 years of age revealed bilateral putamina lesions and periventricular white matter demyelination, supporting the diagnosis of Leigh syndrome. A C214T mutation in exon 3 of the PDHA1 gene was detected. After the treatment of thiamin, coenzyme Q10, Lcarnitine and carbohydrates-restricted diet, his movement ability improved significantly. At present, the patient is 8 years old and has normal school life. PDHA1 deficiency is an X-linked inherited metabolic disease, which shares various clinical manifestations and leads to difficult diagnosis. This patient predominately presented with progressive weakness and was diagnosed by gene analysis.

[Clinical characteristics of cases with leukoencephalopathy with vanishing white matter].

OBJECTIVE: To analyze and review the characteristics of leukoencephalopathy with vanishing white matter (VWM). METHODS: The clinical features including clinical manifestations, neurologic signs, cranial MRI and laboratory tests in 9 patients with the diagnosis of VWM were analyzed and the characteristics of the disease were reviewed. CLINICAL MANIFESTATIONS: 8 cases had symptoms involving central nervous system, 1 case only showed abnormal cranial MRI findings. The onset of the disease occurred between 6 months to 3 years of age. Family history was positive in 5 cases. Almost all cases had normal psychomotor development before the onset of the disease. The initial symptom was usually movement disorder with predominant involvement of lower limbs. The onset or deterioration of the disease was followed by respiratory tract infection in 6 cases and minor head trauma preexisted in 3 cases. The course of the disease was progressive in 7 cases and there was episodic deterioration in 4 cases. Mental abilities were relatively better preserved. Head circumference was normal in 7 cases. Positive upper motor unit signs were found in 8 cases and ataxia in 4 cases. Bilateral optic nerve atrophy was found in 3 cases. Cranial MRI indicated diffuse and symmetrical involvement of deep white matter which showed long T(1) and T(2) signal. Subcortical white matter was also involved with predominance in frontal and parietal lobes. Flair image showed symmetrical high signal intensity in cerebral white matter with low signal intensity similar to that of CSF in partial area or low signal in most area of white matter with only meshwork of higher signal preserved. The results of all the laboratory tests including the enzyme and biochemical test specific for some well-known leukoencephalopathy were normal. CONCLUSIONS: The clinical features of VWM include: 1. Initial symptom is usually movement disorder; 2. Movement disorder is more prominent compared to mental retardation; 3. Cranial MRI shows symmetrical abnormal T(1) and T(2) signal in deep white matter with signs of vanishing white matter. Exclusion of other hereditary and acquired leukoencephalopathy is necessary for diagnosis. Final diagnosis should be made on the basis of genetic evidence.

Detection of abnormal visual cortex in children with amblyopia by voxel-based morphometry.

PURPOSE: To detect the abnormalities of gray matter in children with amblyopia by voxel-based morphometry (VBM). DESIGN: Prospective, nonrandomized clinical trial. METHODS: Thirteen children with amblyopia and 14 normally sighted children underwent magnetic resonance (MR) examination. The two groups were age-matched with a mean age of 5.8 years. In the amblyopia group, five children had strabismus amblyopia, and eight had anisometropic amblyopia. We analyzed the original 3-dimensional T1 brain images using the VBM module within the widely used analysis software package SPM2 (Welcome Department of Cognitive Neurology, London, United Kingdom). After normalization, segmentation, and smoothing of the images, comparison between amblyopic and control groups was derived for the gray matter of the entire brain using parametric statistics. RESULTS: The results of VBM analysis indicated that the amblyopic group had decreased gray matter density in the middle frontal gyrus, parahippocampal gyrus, fusiform gyrus, inferior temporal gyrus of the left hemisphere, and the bilateral calcarine cortices. The radii of these regions ranged from 12 to 36 voxels. These abnormalities were consistent with morphologic changes in brain regions related to visual function. CONCLUSIONS: Using MR and VBM analysis, we detected morphologic changes in the visual cortex of children with amblyopia, which may indicate developmental abnormalities of visual cortex during the critical growth period.