Endocrinological Results of the Transsphenoidal Microsurgery for Cushing's Disease

OBJECTIVE: We analyzed the clinical and endocrinological results of the transsphenoidal microsurgery for ACTH secreting pituitary adenomas. MATERIALS AND METHODS: From October 1995 to August 2000, 18 patients underwent transsphenoidal microsurgery for Cushing's disease. We analyzed the surgical results of 17 patients, one patient who was previously operated from other hospital was excluded. Age of the patients were 18 to 61 years old(mean 37.7), male to female ratio was 1: 3.3, and follow-up period was 3 to 50 months(mean 20.3). The selection of candidates for transsphenoidal exploration was based on endocrinologic criteria. Magnetic resonance imaging was the preferred radiologic test. Selective inferior petrosal sinus sampling of adrenocorticotropic hormone futher refined the diagnosis when endocrinologic and radiologic procedures were not definitive. RESULTS: Results of the preoperative endocrinological test were: level of serum ACTH 29.4 to 225ng/dL(mean 93.88ng/dL); serum cortisol 11.9 to 47.5ng/dL(mean 27.49ng/dL); 24-hour urine free cortisol 235 to 1019ng/day(mean 571.0ng/day). Inferior petrosal sinus sampling for ACTH was performed in 11 patients and all were confirmed by Cushing's disease and we could predict the laterality of the tumor in 9 of 11 patients. We performed transsphenoidal selective adenomectomy in 5 patients, adenomectomy and subtotal hypophysectomy in 2 patients, adenomectomy and partial hypophysectomy in 9 patients, and in the remaining one patient, hemihypophysectomy followed by total hypophysectomy due to remission failure. Fifteen of 17 patients(88.2%) showed endocrinological remission. Glucocorticoid replacement therapy was performed in all the patients who showed remission for 1 to 24 months(mean 5.9 months), and 6 patients received steroid over 6 months. CONCLUSION: We conclude that the direct demonstration of a tumor in the pituitary gland by MRI is the most important and definitive diagnostic tool and the location of a mass should be confirmed with increased level of ACTH by the inferior petrosal sinus sampling. Transsphenoidal microsurgery is effective treatment modality for Cushing's disease and the immediate postoperative evaluation of the surgical resection of the tumor is very important. The patients should show hypocortisolism, decreased, subnormal serum ACTH and cortisol levels and 24-hours urine free cortisol. We performed 18 transsphenoidal microsurgery for Cushing's disease in 17 patients and 15 patients(88.2%) showed endocrinological remission.

Analysis of Usefulness of Biochemical Enzyme Assay and MR Spectroscopy(MRS) in Leigh Syndrome

PURPOSE: Leigh syndrome is a kind of mitochondrial disease with a pathological production of lactate and variable clinical manifestations. Recently biochemical assay of the mitochondrial enzyme activity and MRS are becoming a powerful tool for the definitive antemorterm diagnosis of this disease. The aim of this study was designed to determine the usefulness of biochemical enzyme assay and MRS in Leigh syndrome. METHODS: A clinical study of 8 cases of pediatric patients were diagnosed as Leigh syndrome on the basis of clinical manifestations and MRI features at the department of pediatrics, Ulsan university hospital, from July, 1992 to June, 1997. Biochemical enzyme assay of the cultured skin fibroblasts was consulted to hospital for sick children, Toronto, Canada. Cerebral lactates were detected on MRS were analysed in relation to the MRI findings and lactate levels in the CSF. RESULTS: 1) Age at diagnosis ranged from 7 months to 8.9 years; seven were boys and one was girl. 2) Main clinical symptoms were as follows in the order of frequency; seizure(75%), ophthalmoplegia(50%), hemiplegia(50%), hypotonia(50%), respiratory difficulty(50%), developmental delay(38%), consciousness change(38%), mental retardation( 25%). 3) Anatomical locations of the focal lesions detected on the initial MRI were as follows in the order of frequency; putamen(75%), caudate nuclei(63%), medulla oblongata (18,50%), substantia nigra(38%), thalamus(38%). 4) Biochemical enzyme assay revealed deficiency of NADH cytochrome c reductase (complex I) and deficiency of cytochrome c oxidase(complex N) respectively in 2 patients who had markedly elevated serum and CSF lactate levels and lactate/pyruvate ratio. 5) Cerebral lactates were detected by MRS from 6 lesions of 1 week-4 months old in 6 patients who had normal or mildly elevated serum and CSF lactate levels and lactate/pyruvate ratio. CONCLUSION: MRS detected the brain parenchymal lactate non-invasively from the acute or subacute lesions. Therefore, combined evaluation by MRS and biochemical enzyme assay will provide an important information for the diagnosis and estimation of disease activity in pediatric patients who are suspected to have Leigh syndrome.

A Case of Canavan Disease

Canavan disease(CD) is a rare autosomal recessive leukodystrophy caused by the deficiency of aspartoacylase and the accumulation in brain of N-acetylaspartate(NAA). CD has been reported mainly Ashkenazi Jews but also occurs in other ethnic groups. Usually it presents as early as the third month of life with megalencephaly, hypotonia later progressing to hypertonia, psychomotor and mental retardation, blindness, occasionally deafness and seizure. Diagnosis is based on the clinical feature, N-acetylaspartic aciduria, radiologic and pathologic findings. Histologically, the affected white matter shows extensive vacuolation and demyelination. There is no treatment for CD and the only prevention is through genetic counselling and prenatal diagnosis. We experienced a case of Canavan disease that was presented with hypotonia and developmental delay. Diagnosis was confirmed histologically. Radiologic findings are extensive high signal throughout the white matter on T2-weighted MRI and increased NAA peak and decreased choline peak of the white matter on MR spectroscopy.

Proton Nuclear MR Spectroscopy (H-MRS) in Adult Onset Hallervorden-Spatz Disease

Background & Significance : Hallervorden-Spatz disease (HSD) is a rare neurologic disorder characterized by progressive dystonia, retinal degeneration, pyramidal sign, and mental deterioration. The neuropathological findings include preferential deposition of iron within the extrapyramidal nuclei, including globus pallidus, substantia nigra, and red nuclei. The final diagnosis depends on the typical pathologic findings. MRI brain imaging study commonly shows so-called "eye-of-the-tiger" in the globus pallidus. However 1H-MRS findings of HSD have not been reported. We experienced a case with clinically suspicious HSD whose diagnosis was further supported by 1H-MRS. Case : A forty four year-old man presented with slowly progressive dystonia for six years. He had been well until age of thirty eight, when he noticed clumsy hand-writing. Three years later, he developed difficulty in chewing. Clumsiness of his hands and arm movements progressed to the point of difficulty in using spoon and chopsticks. While walking, arm swing was decreased and both arms and neck took more dystonic posture. Brain MRI (T2Wl) showed symmetric high signal intensity lesions in the globus pallidus, surrounded by a peripheral zone of exaggerated low signal. On 1H-MRS of basal ganglia, although choline, creatine and N-acetyl-aspartate (NAA) peaks were detected, marked noise probably due to paramagnetic substance (iron), made quantitative analysis difficult. Conclusion : 1H-MRS of HSD is characterized by "noise", which may be suggestive of HSD.