Determining Factors for the Reduction of Dopaminergic Drugs after Bilateral Subthalamic Nucleus Deep Brain Stimulation

BACKGROUND: We aimed to investigate the possible factors determining reduction of dopaminergic drugs in patients who received bilateral subthalamic nucleus (STN) deep brain stimulation (DBS). METHODS: We studied 33 consecutive Parkinson's disease (PD) patients who underwent bilateral STN DBS between March 2002 and April 2006. Patients were assessed at baseline and 6 months and 1 year after surgery. RESULTS: The dose of dopaminergic drugs was significantly decreased by 16.5% (p<0.05) and 14.9% (p<0.05), at post op 6 months and 12 months respectively. The reduction rate of dopaminergic drugs after bilateral STN DBS was positively correlated with the dopaminergic drug dosage at baseline (p<0.05) and was negatively correlated with the scores of "off"-period UPDRS II (p<0.05), III (p<0.001), and total UPDRS (p<0.001) at baseline. The difference of UPDRS scores between "on" and "off" periods on the levodopa challenge test was negatively correlated with the reduction rate of dopaminergic drug dosage after bilateral STN DBS (p<0.001). CONCLUSIONS: It is likely that the main determining factors for the reduction of dopaminergic drug dosages after bilateral STN DBS in advanced PD are the UPDRS III score during "off" periods, difference of the UPDRS III score between "on" and "off" periods on the levodopa challenge test and dose of dopaminergic drugs at baseline.

A Case of Spinocerebellar Ataxia Type 6

Spinocerebellar ataxia (SCA) type 6 was recently identified as a form of autosomal dominant cerebellar ataxia associated with the small expansion of CAG repeats. The number of CAG repeats varies from 4 to 18 on normal alleles and 21 to 30 on the SCA type 6 chromosome. SCA type 6 is characterized by cerebellar ataxia and dysarthria associated with cerebellar atrophy. Many patients with SCA type 6 have horizontal gaze-evoked nystagmus, and some have a limitation of eye movements on the upward and lateral gaze. A 59-year-old woman without any noticeable family history presented with slowly progressive cerebellar ataxia, dysarthria, and oscillopsia. She had vertical nystagmus and horizontal gaze-evoked nystagmus. Brain MRI revealed a moderate cerebellar atrophy, most prominent in the vermis, with relative sparing of the brain stem. A genomic polymerase chain reaction (PCR) analysis showed 24 CAG repeats at the SCA6 locus compatible with the sporadic SCA type 6.

A Case of Hashimoto's Encephalopathy

Hashimoto's encephalopathy (HE) is a steroid-responsive disorder of persistent or relapsing neurological or neu-ropsychological deficits associated with elevated serum concentrations of antithyroid antibody that frequently presents with myoclonus, seizures, and stroke-like episodes. We report a 55-year-old woman who presented with an altered men-tality associated with generalized tonic-clonic seizure. She was diagnosed with Hashimoto's thyroiditis 3 years prior. Serum antithyroglobulin antibody and antimicrosomal antibody were elevated. Electroencephalography (EEG) showed generalized slowing. Brain magnetic resonance imaging (MRI) with T2-weighted sequence and fluid-attenuated inver-sion- recovery (FLAIR) image revealed a high signal intensity in both mesial temporal areas. Single photon emission computed tomography (SPECT) demonstrated decreased perfusion in multiple areas. With the impression of HE, she was placed on high dose steroid and thyroid hormone replacement therapy which ameliorated her neurological symp-toms. We suggest that HE should be included in the differential diagnosis of decreased mentality, especially when patients with Hashimoto's thyroiditis show altered consciousness, seizure disorder, or cognitive decline.

H-reflex Studies in Patients with Subclinical Diabetic Polyneuropathy

BACKGROUND: The H-reflex has been used to assess the proximal nerve conduction in radiculopathy or peripheral neuropathy. The purpose of this study was to evaluate the clinical usefulness of the H-reflex in the diagnosis of subclinical diabetic polyneuropathy. METHOD: Thirty-four diabetic patients (17 women and 17 men) who had neither motor nor sensory symptoms were selected (mean age 57.6 +/- 12.9 years). The duration of diabetes varied from 0.5 to 24 years (mean 6.2 +/- 5.1 years). None of the patients had any known cause of peripheral neuropathy other than diabetes. Twenty-seven healthy subjects (16 women and 11 men) were evaluated as an age-matched control group. H-reflex studies were performed using Braddom and Johnson's methods. The presence and latencies of the H-reflexes were examined in both legs. RESULTS: Twenty-four of the 34 patients (70.6%) had abnormal H-reflex responses (absent H-reflex in 17, prolonged latency in 7). However, only three out of the 27 control subjects (11.1%) had abnormal H-reflex responses (absent H-reflex in 1, prolonged latency in 2). CONCLUSIONS: Abnormalities in H-reflex studies have often been seen in diabetic subjects without overt neurological symptoms. This study suggests that the H-reflex study may be a useful screening tool in the diagnosis of subclinical diabetic polyneuropathy.

A Case of Spinal Stroke Due to the Obstruction of Adamkiewicz Artery

BACKGROUND: Spinal stroke is unusual, accounting for 1% of all cases of stroke in general hospital. The clinical features of anterior spinal artery syndromes due to Adamkiewicz artery obstruction are dissociative sensory disturbances, motor weakness, and autonomic dysfunctions. There have been several reports of using magnetic resonance imaging(MRI) in ischemic spinal cord infarctions. However, angiographic and MRI finding of the obstruction of Adamkiewicz artery has never been reported in Korea. CASE: A previously healthy 60-year-old woman presented an acute onset of paralysis of both lower limbs. On admission she showed paralysis and anesthesia of both lower limbs, and loss of bladder function. Routine hematological and CSF studies revealed no abnormalities. MRI disclosed T11-L2 level spinal cord infarction on T1- and T2-weighted images. Posterior tibial somatosensory evoked potential study revealed prolongation of cortical waves. Spinal angiographic findings were compatible with spinal cord infarction due to the obstruction of Adamkiewicz artery. COMMENT: To our knowledge, this is believed to be the first case of spinal stroke due to the obstruction of Adamkiewicz artery confirmed both by MRI and by angiography in Korean literature.

Hypertrophic intracranial pachymeningitis associated with chronic otitis media: A case report

A 59-year-old woman was admitted to our hospital because of occipital headache and multiple cranial nerve dysfunction. The patient had been suffered from chronic otitis media. MRI of the brain showed a thickened and markedly enhanced dura mater in the temporal lobe. The patient underwent a left temporal craniectomy and dural biopsy. Histopathological examination revealed thickened duar amter infiltrated with giant cell, lymphocytic and plasma cell infiltration. The fungus, acid-fast and PAS stains were all negative. After administraion of steroid, cranial nerve disturbances and headache improved. The cause of the hypertrophpic intracranial pachymeningitis in this patient was thought to be related with the chronic otitis media, although the clinical course of the patient was similar to the idiopathic hypertrophic pachymeningitis.