Structural MRI and MRS abnormalities in bipolar disorder

Soares JC. Structural MRI and MRS abnormalities in bipolar disorder. Bipolar Disord 2002: 4(Suppl. 1): 87. © Blackwell Munksgaard, 2002     

Neurologic aspects of adenylosuccinate lyase deficiency

Adenylosuccinate lyase deficiency is an autosomal-recessive disorder of the purine de novo synthesis pathway, diagnosed up to now in approximately 40 patients. The clinical presentation is characterized by severe neurologic involvement including seizures, developmental delay, hypotonia, and autistic features. Neonatal seizures and a severe infantile epileptic encephalopathy are often the first manifestations of this disorder. The existence of genetic heterogeneity for the adenylosuccinate lyase defect could account for variability of the clinical presentation. Deficiency of purine nucleotides, impairment of energy metabolism, and toxic effects are potential mechanisms of cerebral damage. Laboratory investigations show the presence in urine and cerebrospinal fluid of succinylpurines, which are normally undetectable. Currently, no effective treatment is available for adenylosuccinate lyase deficiency. A search for this disorder should be included in the screening program of children with unexplained neonatal seizures or severe infantile epileptic encephalopathy.     

Cerebral abscess: MRI, DWI and MRS features

Although rare in non immunodeficient patients, the correct diagnosis of brain abscess is essential in order to initiate urgent medical and surgical treatment. We describe the imaging features including spectroscopy and diffusion MRI.     

MRI and MRS of Coffin-Lowry syndrome: a case report

MRI and MRS were used to examine the brain and the spine of a Coffin-Lowry syndrome (CLS) patient. There were moderately enlarged lateral and third ventricles and subarachnoid space with prominent Virchow-Robin spaces. MRS of basal ganglia and periventricular white matter was normal.     

Intrapontine malignant nerve sheath tumor: MRI and MRS features

The primary source of malignant intracerebral nerve sheath tumors is still unclear We report the imaging and MR spectroscopic findings in a 39-year-old man with a very rare brain stem tumor MR examination revealed the presence of intraaxial brain stem tumor with a partial exophytic growth. On pathological examination, the neoplasm appeared to be an intrapontine nerve sheath tumor originating most likely from the intrapontine segment of one of the cranial nerve fibres. The tumor showed exophytic growth, with consequent spread to adjacent subaracnoid space. MR spectroscopy revealed the presence of very high concentration of choline, associated with no creatine and N-acetyl aspartate resonance, suggesting non-glial origin of the intraaxial neoplastic infiltration. MR spectroscopy seems to be a helpful diagnostic modality not only in the estimation of the grade of astrocytomas that has been already confirmed in literature, but also in the diferentiation between glial and non-glial origin of primary intracranial neoplasms when MR imaging is not conclusive.     

MRI及磁共振波谱对弥漫性轴索损伤的临床诊断优势

目的探讨MRI及磁共振波谱(MRS)对早期重型颅脑损伤中弥漫性轴索损伤的临床诊断优势。方法选取2010年1月~2014年5月在解放军第171医院接受CT检查及综合治疗的27例急性重型颅脑损伤患者,入院7 d内进行头颅MRI及MRS检查,采用磁共振扫描仪及超导磁共振进行T1、T2、Flair序列扫描,选择合适的靶点进行MRS检查,明确颅脑损伤的部位及性质。对头颅CT、MRI及MRS的弥漫性轴索损伤影像学图片及资料进行比照,并且对比头颅CT与MRI+MRS对弥漫性轴索损伤其中包括原发性脑干损伤的检出率,并分析MRS检出损伤部位与预后的关系。结果 CT对弥漫性轴索损伤的总检出率为33.3%,其中原发性脑干损伤的检出率为25.9%;MRI及MRS对弥漫性轴索损伤的总检出率为85.2%,其中原发性脑干损伤的检出率为51.9%,差异均具有统计学意义(均P0.05)。MRI及MRS检出损伤的患者组的Barthal指数及DRS均分与未检出异常的组间差异均具有统计学意义(均P0.05)。Barthal指数41~60分和≤40分患者的NAA/Cr、NAA/Cho与60分患者比较,差异具有统计学意义(均P0.05)。DRS均分为4~30分患者的NAA/Cr、NAA/Cho与DRS均分为0~3分比较,差异具有统计学意义(均P0.05)。结论 MRI与MRS在早期重型颅脑损伤中弥漫性轴索损伤的临床诊断上具有明显优势,值得临床推广。     

Tobacco smoking and MRI/MRS brain abnormalities compared to nonsmokers

This mini review emphasizes the fact that tobacco smoking causes small but real biologic brain changes that need to be studied in depth. A crucial question is whether these anatomical/chemical changes reverse toward normal when smokers quit. This review is presented to stimulate further research to answer this question.     

Atypical presentation and neuropathological studies in 3-hydroxy-3-methylglutaryl-CoA lyase deficiency

A 6 1/2-month-old male offspring of consanguineous Egyptian parents was first seen because of fever, somnolence, vomiting, right focal motor seizures, right hemiparesis, elevated transaminase levels, hyperammonemia, and acidosis. A computed tomographic scan of the head suggested swelling of the left cerebral hemisphere, and an electroencephalogram indicated left frontotemporal abnormalities, but brain biopsy demonstrated diffuse white matter spongiosis and gliosis. Subsequently, urine organic acid analysis and enzyme assays were diagnostic of 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency.     

MRI/~1H-MRS在MELAS综合征与卒中鉴别诊断中的应用研究

目的探讨线粒体脑肌病伴高乳酸血症及卒中样发作(MELAS)综合征头颅磁共振(MRI)及头颅磁共振波谱(~1H-MRS)特点与其早期诊断价值。方法对8例诊断为MELAS综合征患者的MRI及MRS结果进行分析。结果 8例MELAS综合征患者的头颅MRI结果示病变累及多个脑叶,主要包括额叶、颞叶、顶叶、枕叶皮质及双侧基底核、放射冠区,其中4例患者可见不同程度的脑萎缩;头颅磁共振血管造影(MRA)检测均未见颅内动脉异常,且病灶区域与主要供血动脉分布无明显相关性;4例患者头颅~1H-MRS可见病变区域显著Lac峰,以及病灶区NAA峰显著降低。结论头颅~1H-MRS能够为MELAS综合征患者提供无创性检查,分析脑组织能量代谢变化,对MELAS综合征的早期诊断具有重要价值。     

AEEG、MRI与MRS对非惊厥发作癫((癎))的诊断价值

目的探讨动态脑电图(AEEG)和头颅MRI与磁共振波谱分析(MRS)检查对临床非惊厥发作癫癎的诊断和和鉴别诊断意义。方法对76例临床拟诊非惊厥发作癫癎患者行AEEG、MRI与MRS检查,并将检查结果进行分析。结果确诊癫癎56例,其中MRI异常57.1%、~1HMRS异常76.8%。结论AEEG、头颅MRI与MRS对非惊厥发作癫癎的诊断和鉴别诊断有重要意义。     

Adenylosuccinate lyase deficiency: the first identified polish patient

Adenylosuccinate lyase (ADSL) deficiency is a rare disease of de novo purine synthesis. The main symptoms are psychomotor retardation, epilepsy, autistic features, occasionally associated with muscular hypotonia. Diagnosis is made by detection of abnormal purine metabolites (succinyladenosine - S-Ado and succinylaminoimidazole carboxamide riboside - SAICAr) in body fluids. The severity of the clinical features correlates with low S-Ado/SAICAr ratio. We report clinical, biochemical and brain MRI findings of a female infant with severe early epilepsy and hypotonia, who died at the age of 10 weeks.     

Frontal lobe metabolism and cerebral morphology in schizophrenia: P MRS and MRI studies

The relation between frontal lobe membrane phospholipid metabolism as measured by ³¹Phosphorus magnetic resonance spectroscopy (³¹P MRS) and cerebral morphology as measured on magnetic resonance images (MRI) was examined in nine first episode neuroleptic naive schizophrenic patients. Total corpus callosal area was significantly correlated with phosphodiester concentration. When examined separately, this relation was confined to the rostral quartile (genu) of the corpus callosum. The pathophysiological significance of this finding is discussed in relation to neurodevelopmental hypotheses of schizophrenia.     

Acute disseminated encephalomyelitis: an MRI/MRS longitudinal study

A clinical and radiologic diagnosis of acute disseminated encephalomyelitis was made in two children: a 6-month-old female who presented with focal seizures and thalamic and cerebral white matter lesions, and a 4.5-year-old male who presented with tremor and dystonia and had bilateral basal ganglia lesions, without evidence of active brain infection. Serial clinical and laboratory evaluations were supplemented by neuroimaging including routine magnetic resonance imaging and ¹H magnetic resonance spectroscopy. They were treated symptomatically, without using steroids or intravenous immunoglobulin, and both children recovered. Single voxel ¹H magnetic resonance spectroscopy data were acquired from the involved areas and from normal-appearing white matter. Abnormalities in N-acetyl-aspartate, choline, and lactate peaks were evident during the symptomatic phase, and persistence of low N-acetyl-aspartate was observed during recovery. These spectroscopic findings are consistent with neuropathologic findings of neuronal dysfunction, cellular membrane turnover, cellular infiltration, and metabolic stress in the acute phase, and with neuronal loss in the chronic phase. Gabis LV, Panasci DJ, Andriola MR, Huang W. Acute disseminated encephalomyelitis: An MRI/MRS longitudinal study.     

MRI findings in cobalamin deficiency.

A 55 year old male presented 2 years after a jejuno-iliectomy with weakness of all limbs, paraesthesiae, and difficulty in walking. Clinical examination revealed loss of posterior column sensations. Investigations were suggestive of a deficiency of vitamin B12 and folate. MRI showed a band of hyperintensity on T2 image, in the dorsal portion of the spinal cord.     

3-hydroxy-3-methylglutaryl-CoA lyase deficiency in an adult with leukoencephalopathy

3-Hydroxy-3-methylglutaryl-CoA lyase deficiency is a disorder of leucine metabolism that usually presents with recurrent episodes of life-threatening hypoglycemia during early childhood. We report on a 36-year-old woman with seizures, recurrent metabolic disturbances, and severe leukoencephalopathy. The diagnosis was made by analysis of amino acids in urine and serum and was confirmed by demonstration of the deficient enzyme in cultured skin fibroblasts. The patient improved clinically on oral L-carnitine substitution. This treatable condition can remain unrecognized in adults and should be considered a potential cause of leukoencephalopathy.     

Quantitative proton MRS of cerebral metabolites in laminin alpha2 chain deficiency

Congenital muscular dystrophy (CMD) due to merosin (laminin alpha2 chain) deficiency is an autosomal recessively inherited disorder characterized by severe muscular weakness and hypotonia from birth on. Brain involvement is the rule and characterized by variable T2 hyperintensities of white matter which appears swollen on cranial MRI. The pathophysiology of these white matter changes is not clear. In five patients with laminin alpha2 deficient CMD we performed short-echo time localized proton MRS with determination of absolute metabolite concentrations in grey and white matter. In affected white matter, a consistent pattern of metabolites was detected comprising reduced concentrations of N-acetylaspartate and N-acetylaspartylglutamate, creatine, and phosphocreatine, and to a milder degree of choline-containing compounds. In contrast, concentrations of myo-inositol were in the normal range. Spectra of cortical and subcortical grey matter were normal. The observed metabolite profile is consistent with white matter edema, that is reduced cellular density, and relative astrocytosis. This interpretation is in line with the hypothesis that laminin alpha2 deficiency results in leakage of fluids across the blood-brain barrier and a histopathological report of astrocytic proliferation in CMD.     

Neuro-Beh?et: acute and sequential aspects by MRI and MRS.

Three patients with neuro-Beh?et underwent MRI and MRS during acute illness. After therapy, MRI and MRS were performed in 3 and 1 patients, respectively. MRI revealed a marked improvement of the initial lesion in 2, a complete remission in 1 patient. MRS showed a reduction of the N-acetyl-aspartate (NAA)/phosphocreatine (CR) ratio within the acute lesion in all patients and a normalization in the follow-up spectrum of the examined patient.     

Muscle MRI in adult-onset acid maltase deficiency

We report the spectrum of muscle involvement on magnetic resonance imaging in 11 patients with a molecularly confirmed diagnosis of adult-onset acid maltase deficiency at different clinical stages. Muscle magnetic resonance imaging showed a selective progressive pattern of muscle involvement with a constant involvement of the adductor magnus and semimembranosus at the early stage of the disease and a later fatty infiltration of the long head of the biceps femoris, semitendinosus and of the anterior thigh muscles. In the advanced phases a selective sparing of sartorius, rectus, and gracilis muscles and peripheral portions of the vastus lateralis was also evident. Muscle strength and magnetic resonance imaging findings were positively correlated. The results suggest that muscle magnetic resonance imaging may provide valuable diagnostic guidance for the assessment of accurate selective muscular involvement in acid maltase deficiency and may help monitor the progression of the disorder. Further control studies in a larger cohort are needed to evaluate the specificity of these findings.