¹8F-FP-(+)-DTBZ positron emission tomography detection of monoaminergic deficient network in patients with carbon monoxide related parkinsonism.

BACKGROUND AND PURPOSE: Although parkinsonism after carbon monoxide (CO) intoxication is well known, neurotransmitter deficient networks that are responsible for the severity of parkinsonism have rarely been systemically evaluated. METHODS: Eighteen patients with CO-related parkinsonism and nine age- and sex-matched controls were enrolled for detailed neurological examinations, three-dimensional T1-weighted images, diffusion tensor imaging and (18)F-9-fluoropropyl-(+)-dihydrotetrabenzazine ((18)F-FP-(+)-DTBZ) positron emission tomography (PET). The structural analysis included voxel-based morphometry to assess grey matter atrophy and tract-based spatial statistics related to white matter involvement. For presynaptic monoaminergic assessment, volume of interest analysis in six subcortical regions and non-parametric voxel-wise comparison were performed on PET images with estimation of registration parameters from magnetic resonance images. All the imaging modalities were compared between the patients and controls. For the patients, a regression model for correlation with cognitive behaviour and Unified Parkinson's Disease Rating Scale (UPDRS) score was used. RESULTS: In the patients, monoaminergic deficit networks were found in the caudate, anterior putamen, anterior insular, thalamus and anterior cingulate cortex. The UPDRS revealed significant correlations with the prefrontal white matter fractional anisotropy values and with the (18)F-FP-(+)-DTBZ uptake values in the caudate nucleus, insular, medial prefrontal and dorsomedial thalamus. The neuropsychiatric inventory score correlated with the (18)F-FP-(+)-DTBZ uptake values in the anterior cingulate cortex and dorsolateral prefrontal cortex. CONCLUSIONS: Our study demonstrated monoaminergic deficits and white matter damage networks in CO-related parkinsonism that determined the severity of parkinsonism or behaviour changes. As the substantia nigra was spared, the monoaminergic topography of involvement suggests a different pathophysiology in CO-related parkinsonism.

Impact of homocysteine on cortical perfusion and cognitive decline in mild Alzheimer's dementia.

BACKGROUND AND PURPOSE: Elevated plasma total homocysteine level (tHcy) is associated with increased risk of dementia via increased white matter changes or reduction in cortical volume. Whether tHcy has an independent impact on regional perfusion and if it can predict a more rapid cognitive decline in mild Alzheimer dementia (AD) warrants investigation. METHODS: Eighty AD patients with a clinical dementia rating of 1 were enrolled. Their Cognitive Ability Screening Instrument (CASI) scores on enrolment and after 1 year of follow-up as well as their perfusion index (PI) from single photon emission computed tomography upon enrolment were analyzed. RESULTS: In cross-sectional analysis, elevated tHcy was associated with lower frontal PI independent of cerebrovascular risk factors (ß = -0.35, P = 0.009). The CASI scores correlated with temporo-parietal PI (Pearson r range 0.3-0.39, P < 0.01) but not with tHcy or frontal PI. By longitudinal analysis, only tHcy level was related to a more rapid cognitive decline (odds ratio for executive function score 1.82; odds ratio for total CASI score 1.74). CONCLUSIONS: Cognitive performance in mild AD can be reflected by hypo-perfusion of the temporo-parietal region while frontal hypo-perfusion may be mediated by tHcy. tHcy level is an independent risk factor for rapid cognitive decline, especially in the executive function.

Cognitive deficits in multiple system atrophy correlate with frontal atrophy and disease duration.

BACKGROUND AND PURPOSE: Dementia remains an exclusion criterion in diagnosing multiple system atrophy (MSA). This study aimed to determine the cognitive changes and brain atrophy patterns in the Parkinsonian (MSA-P) and cerebellar (MSA-C) variants of MSA. METHODS: Voxel-based morphometry (VBM) of magnetic resonance imaging (MRI) and neuro-psychological tests were applied to 10 MSA-C and 13 MSA-P patients, and compared to 37 age-matched controls. Correlation analyses were performed between cognitive test results and morphometric data extracted from the VBM data. RESULTS: In neuro-psychological testing, the 23 MSA patients scored lower in the Stroop interference test and took longer in the trail-making test as compared with the controls, whereas MSA-C performed worse than MSA-P in the memory scores, Stroop test, and time to complete the trail-making test. MSA, as a group, showed atrophy in the cerebellum, insular cortex, fusiform gyrus, inferior orbito-frontal gyrus, superior temporal gyrus, and caudate nucleus. Memory scores correlated well with pre-frontal lobe atrophy but not in the insular area. CONCLUSION: In conclusion, although dementia is not a typical presenting feature of MSA and is regarded as a sub-cortical movement disorder, frontal atrophy, cognitive changes, and dementia are identifiable as MSA progresses.

Hepatocellular carcinoma presenting as nervous system involvement.

To analyze the clinical features of hepatocellular carcinoma (HCC) in patients with signs and symptoms of nervous system involvement as the initial presentation. Over a period of 11 years (January 1993 to December 2003), 15,008 HCC patients were identified at the Chang Gung Memorial Hospital in Kaohsiung, Taiwan. Amongst them, 42 cases had nervous system involvement, of which six had nervous system involvement as their initial presentation. These six cases were enrolled in this study and their clinical and laboratory data were analyzed. The clinical features of the other 36 HCC cases with nervous system involvement were also analyzed for comparison. The six cases were all males, aged 36-68 years old. The involved parts of the nervous system were the cerebellar hemisphere (one), the frontal lobe (one), the sphenoid sinus, sellar turcica, and cavernous sinus (one), the cervical spine (one), and the thoracic spine (two). Their corresponding neurologic presentations were back pain, headache, consciousness disturbance, visual disturbance, and limb weakness. Whilst three out of six patients presenting with nervous system manifestations were found to have concurrent systemic metastases in other expected sites (lung, bone), three had isolated nervous system involvement even after extensive work up. The associated medical conditions of the six cases included hepatitis B (three), hepatitis C (one), liver cirrhosis (two), portal vein thrombosis (three), and diabetes mellitus (two). All the six died within 9 months after the detection of nervous system involvement. The prevalence of nervous system involvement in HCC patients is 0.28% (42/15,088), with 0.04% (6/15,088) having this as their initial presentation. The prognosis of HCC with nervous system involvement is grave. Their clinical and laboratory data are not unique but the diagnosis could only be confirmed by hepatic and nervous system imaging studies, histopathologic examination, and serum alpha-fetoprotein detection. This consideration should be emphasized especially in areas that are hyperendemic for HCC and if the original focus of metastatic lesion is obscure.

Time course of cerebral hemodynamics in cryptococcal meningitis in HIV-negative adults.

To evaluate the cerebral hemodynamics in cryptococcal meningitis (CM) patients using non-invasive studies. Serial trans-cranial color-coded sonography (TCCS) and magnetic resonance angiography (MRA) studies were performed to measure the cerebral vasculopathy of 12 HIV-negative CM patients. With TCCS, 8 of the 22 middle cerebral arteries (MCAs) showed stenotic velocities, whereas the time-mean velocity (V(mean)) of the 20 anterior cerebral arteries (ACAs), 22 posterior cerebral arteries (PCAs), and 12 basilar arteries (BAs) did not. In total, five patients had stenotic velocities, three of whom had bilateral M1 stenosis (<50%), whilst two had unilateral M1 stenosis (<50%). The V(mean) of MCA increased from day 1 to day 35 and substantially decreased thereafter. The mean Pulsatility Index (PI) in the studied vessels was higher during the study period. A mismatch of the findings between TCCS and MRA studies were also demonstrated. There was a high incidence and a longer time-period of disturbed cerebral hemodynamics during the clinical course of CM. However, because of the limited case numbers for this study, further large-scale studies are needed to delineate the clinical characteristics and therapeutic influence of cerebrovascular insults in HIV-negative CM patients.

Cerebral haemodynamics in acute bacterial meningitis in adults.

BACKGROUND: Vascular complications are an important cause of neurological sequelae among adult survivors of acute bacterial meningitis (ABM). AIM: To examine the haemodynamic changes associated with ABM. METHODS: Serial transcranial colour-coded sonography (TCCS) and magnetic resonance angiography (MRA) were used to examine cerebrovascular changes in adult ABM patients. Outcome at 3 months was categorized using a modified Barthel index. RESULTS: We recruited 24 patients, 12 men and 12 women, aged 21-68 years. Mean cerebral blood flow velocity (V(mean)) increased from day 1 to day 4 in the middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA). On day 4, V(mean) values in the MCA, ACA and PCA were all significantly higher than reference values in healthy volunteers. At 3 months follow-up, 16 cases had good outcomes, while the other eight had poor outcomes. Under multiple logistic regression analysis, only Glasgow coma score (GCS) at admission was independently associated with the three-month outcome. DISCUSSION: In these patient, stenosis as demonstrated by TCCS did not wholly coincide with stenosis as demonstrated by MRA, and the presence of intracranial stenosis was not predictive of a poor outcome at 3 months. Further studies are needed to delineate the characteristics and significance of cerebrovascular changes in adult ABM.

Factors predictive of fatality in massive middle cerebral artery territory infarction and clinical experience of decompressive hemicraniectomy.

To determine the factors predictive of fatality in massive middle cerebral artery (MCA) territory infarction and outcome of decompressive hemicraniectomy, 62 patients who were retrospectively verified with first event massive MCA infarctions were enrolled in this study. Amongst them, 21 received decompressive hemicraniectomy during hospitalization. Clinical data between early and late hemicraniectomy groups were also compared. Significant deterioration occurred in 40 cases, 21 of whom received decompressive hemicraniectomy. The other 19 received conservative treatment. The mortality rate of these 40 cases between decompressive hemicraniectomy and conservative treatment was 29% (six of 21) and 42% (eight of 19), respectively. Factors that predicted fatalities in our massive MCA infarction patients with or without decompressive hemicraniectomy were total scores of baseline GCS at the time of admission, associated with coronary artery diseases, and significant deterioration during hospitalization. This study confirms the lifesaving procedure of hemicraniectomy that prevents death in patients deteriorating because of cerebral edema after infarction, although it may produce severe disability with an unacceptably poor quality of life in survival. Despite high mortality and morbidity, decompressive hemicraniectomy to prevent cerebral herniation when significant deterioration is demonstrated are essential for maximizing the potential for survival.

Treatment outcomes and prognostic factors in patients with supratentorial low-grade gliomas.

Low-grade gliomas account for 10-15% of all adult primary intracranial tumours. Currently, there is no consensus on the treatment strategy for low-grade gliomas. This study was designed to evaluate the treatment outcomes, prognostic factors and radiation-related late complications, as well as to assess whether or not post-operative radiotherapy has benefit on local control and overall survival in this population. We retrospectively reviewed 93 consecutive adult patients with supratentorial low-grade gliomas diagnosed at our institution from July 1985 to December 1997. All patients underwent surgical intervention and 60 of them received post-operative radiotherapy. With a median follow-up of 110 months for surviving patients, the 5-year overall and progression-free survival rates were 57% and 47%, respectively. 46 patients experienced local progression of disease during the follow-up period. In multivariate analysis, age at diagnosis, extent of surgery and post-operative Karnofsky performance status showed independent prognostic significance for progression-free and overall survival rates. Post-operative radiotherapy had independent prognostic value for progression-free survival. This analysis has changed our practice and we suggest that aggressive surgical resection and post-operative radiotherapy might be considered for patients with low-grade gliomas. Further efforts should be made to optimize radiotherapy techniques and to integrate new therapeutic modalities.

Computed tomography findings of bony regeneration after radiotherapy for nasopharyngeal carcinoma with skull base destruction: implications for local control.

PURPOSE: To evaluate the response of bony destruction (BD) of the skull base following radiotherapy in nasopharyngeal carcinoma (NPC) and investigate the implications of bony regeneration (BR) on local control and its related factors. METHODS AND MATERIALS: Ninety patients with NPC with skull base destruction clearly demonstrated on computed tomography (CT) were reviewed. These patients have completed the prescribed treatment and received regular CT follow-up. A total of 338 sets of CT images of the head and neck were reviewed. The tumor response and the appearance of BR in the previous destructive part of the skull base were recorded and analyzed. The tumor response was divided into complete, partial, or no response. BR was defined as recalcification or sclerotic change with partial or complete healing in the previous osteolytic bony defect. Local failure was confirmed either by pathological or merely by imaging studies showing progression of tumor in consecutive radiological pictures. RESULTS: The distribution of specific sites of bony destruction (BD) in these patients included the sphenoid bone (68%), paracavernous sinus area (48%), petrous apex (47%), clivus (44%), pterygoid plates (20%), and others (7%). The CT showed 57 patients (63%) had BR. All were observed within 1 year after treatment. Sixty-two patients (69%) had complete tumor response after treatment. Analyzed by logistic regression method, tumor response after treatment was found to have a statistically significant correlation with BR (p = 0.0004). Most BR (55/57) was demonstrated in patients with complete tumor response. The 3-year actuarial local control rate was 54 % in these patients. The local control was quite different in the comparison of patients with BR versus those with persistent BD (77% vs. 21%, p < 0.0001). Multivariate analysis showed that patients with complete tumor response or with BR on imaging had statistically better local control than those without either of the two findings (p < 0.05). CONCLUSION: Appearance of BR at previous destructive skull base following radiotherapy for NPC patients could be clearly demonstrated on CT. Bony regeneration significantly correlated with treatment response and local control. Although the underlying significance of BR was unknown, to predict the outcome after treatment, the appearance of BR shown on CT may imply the complete eradication of tumor in this area.

Successful treatment of acute inferior vena cava and unilateral renal vein thrombosis by local infusion of recombinant tissue plasminogen activator.

Renal vein thrombosis can occur as a complication of nephrotic syndrome. We present the case of a young man with nephrotic syndrome caused by minimal change disease who developed acute inferior vena cava and left renal vein thrombosis. He was treated initially with intravenous heparin. Because of the persistence of severe left flank pain and gross hematuria, local infusion of recombinant tissue plasminogen activator was tried, with resolution of thrombi and subsidence of symptoms. Functional preservation of the involved kidney is good, as indicated by Tc-99m DMSA scan (involved kidney, 47.4%; uninvolved kidney, 52.6%). Anticoagulation is usually recommended as the treatment of choice in renal vein thrombosis. We believe that in cases with critical presentations, such as bilateral involvement, extension into inferior vena cava, acute renal failure, pulmonary embolism or severe flank pain, thrombolytic therapy should be considered as a second-line treatment if good response is not obtained with heparin.

Unusual short rib-polydactyly syndrome.

We present a case of lethal short rib-polydactyly syndrome (SRPS) that cannot be categorized into the existing classification. A nosologic discussion is presented. To our knowledge, situs inversus totalis, as in our case, has not been described before in any SRPS.

Cerebral infarction in chronic meningitis: a comparison of tuberculous meningitis and cryptococcal meningitis.

Twenty-eight patients with cerebral infarction secondary to chronic meningitis were retrospectively identified at our institution over a period of 5 years. They accounted for 47% (17/36) of tuberculous meningitis (TBM) and 32% (11/34) of cryptococcal meningitis cases. Single infarctions were found in 15 patients and multiple infarctions in 13. The distribution of single infarctions was: basal ganglia 7; internal capsule 3; thalamus 1; cerebellum 1; and cortical infarct 3. Therapeutic outcomes at 3 months were determined using a modified Barthel INDEX: At follow-up of 3 months or more, 10 had good outcomes while the other 18 had poor outcomes. The 18 with poor outcomes included six who died, and 12 who had severe neurological sequelae. TBM and cryptococcal meningitis shared similar clinical features, both being frequently associated with other neurological complications, including hydrocephalus, cranial nerve palsy, and seizures in our patients. However, extracranial involvement, such as spinal and pulmonary involvement, was more commonly found in TBM patients. Cerebral infarction can occur in both the acute stage and later stages of treatment. Mortality and morbidity are high, and early diagnosis and appropriate antimicrobial treatment are essential. If hydrocephalus is demonstrated, early ventricular decompression is needed to prevent further cerebral ischaemia.

Cerebral infarction in perinatal and childhood bacterial meningitis.

BACKGROUND: Cerebral infarction is an important neurological complication of childhood bacterial meningitis, but little is known about its epidemiology and outcomes. AIM: To determine the predictive factors, clinical features, causative pathogens, and outcomes of cerebral infarction secondary to perinatal and childhood bacterial meningitis. DESIGN: Retrospective analysis METHODS: Over the period 1986-2001, 166 perinatal and childhood patients were identified as having culture-proven bacterial meningitis, of whom 14 had cerebral infarction at admission. The clinical and CSF data of patients with and without cerebral infarctions on admission were compared. RESULTS: Cerebral infarction patients accounted for 10% (14/166) of bacterial meningitis cases, mostly in the first year of life (11/14, 79%). Salmonella species (n = 4) and Streptococcus pneumoniae (n = 4) were the most frequent causative pathogens, accounting for 57% (8/14) of episodes. Single infarctions were found in four patients and multiple infarctions in 10. At 1 year follow-up, outcome was good in three, but poor in 11. Significant differences between the two patient groups at admission included age bands, presence of seizures, hydrocephalus, disturbed consciousness on admission, and CSF lactate concentration. DISCUSSION: There was a high prevalence of cerebral infarctions when the disease was caused by S. pneumoniae and Salmonella species. Occurrence was highest in the first year of life, and the prognosis in this patient group is poor. Risk factors associated with cerebral infarction in our patients included age 28-365 days, seizures, hydrocephalus, disturbed consciousness on admission, and high CSF lactate concentrations.

Acute flaccid paralysis in infants and young children with enterovirus 71 infection: MR imaging findings and clinical correlates.

BACKGROUND AND PURPOSE: Enterovirus 71 (EV71) infection is now considered an important cause of childhood acute flaccid paralysis. The purpose of our study was to determine whether EV71-infection-related acute flaccid paralysis in infants and young children has characteristic MR imaging patterns. METHODS: Seven infants and young children with acute paralysis of the upper or lower extremities and positive EV71 cultures underwent spinal MR studies during an outbreak of hand-foot-and-mouth disease in Taiwan in 1998. RESULTS: Acute paralysis was observed in one upper extremity in two patients, in one lower extremity in three patients, and in both lower extremities in two patients. None of the patients had sensory impairment or bulbar palsy. MR studies showed unilateral or bilateral hyperintense lesions in the anterior horn regions of the cord on T2-weighted images in six patients. No abnormal signal was present in one patient. Two of three patients who received intravenous injections of contrast material had ventral root enhancement on T1-weighted images. One of them also had enhancement of the unilateral anterior horn cells. At clinical follow-up, both patients with bilateral anterior horn abnormalities had residual motor weakness, whereas only one of the five patients with unilateral involvement had residual weakness. CONCLUSION: EV71 radiculomyelitis tends to be unilateral and to specifically involve both the anterior horn cells of the cord and the ventral roots. MR imaging allows early detection of spinal cord and root lesions.

Hemifacial spasm caused by a venous angioma. Case report.

The authors describe the case of a 53-year-old woman who suffered from a hemifacial spasm caused by a venous angioma in the posterior fossa. At operation the parenchymal segment of the angioma was preserved and vascular decompression was performed by placing pieces of shredded Teflon between the vessel and nerve. After decompression the patient was completely free from spasm.

Atlantoaxial stability in ossiculum terminale. Case report.

The authors describe a patient with ossiculum terminale. Thin-section three-dimensional computerized tomography reconstructions, magnetic resonance images, and radiographs of the cervical spine were obtained to evaluate the atlantoaxial stability and structures of the ossiculum terminale. Bone had formed between the ossicles and the body of the odontoid process, and good atlantoaxial stability was clearly demonstrated.

Atlantal stenosis: a rare cause of quadriparesis in a child. Case report.

The authors report the case of a 3-year-old boy who suffered from quadriparesis and respiratory distress after failing to execute a somersault properly. Neuroimaging revealed spinal cord contusion with marked spinal canal stenosis at the level of the atlas. No subtle instability, occult fracture, or other congenital abnormalities were confirmed. Spinal cord contusion with marked canal stenosis is rare, and only several adult cases have been reported. Severe stenosis at the level of the atlas may predispose individuals to severe spinal cord contusion, as occurred in our patient after sustaining trivial trauma.

Superior sagittal sinus thrombosis induced by thyrotoxicosis. Case report.

There is a wide variety of disorders associated with thrombosis of the superior sagittal sinus (SSS), including infectious disease. noninfectious conditions such as vasculitis and hypercoagulable states, and complications arising from pregnancy or use of oral contraceptive medications. Despite these well-defined associations, approximately 25% of the cases remain idiopathic. In this article the authors describe a patient who was found to have SSS thrombosis while experiencing a thyrotoxic phase of Graves disease. The patient presented with intracerebral hemorrhage, subarachnoid hemorrhage, seizure, coma, a raised fibrinogen concentration, low protein C activity, and atrial fibrillations. Thrombolysis was successfully performed despite the coexistence of thrombosis and intracranial hemorrhage. Patients with thyrotoxicosis and a diffuse goiter may be predisposed to the development of SSS thrombosis, as a result of hypercoagulation and stasis of local venous blood flow. In the present case, a patient in whom thrombosis coexisted with intracranial hemorrhage was successfully treated using thrombolytic therapy.

Unilateral palate paralysis in patients with nasopharyngeal carcinoma: imaging and clinical correlations.

OBJECTIVE: Neck masses, hearing impairment, and blood-tinged nasal discharges are three major clinical manifestations of nasopharyngeal carcinoma (NPC). Because of the relationship between the anatomic structures of the fossa of Rosenmüller and the levator veli palatini muscle, NPC arising in the fossa can invade the levator muscle, limiting movement or causing paralysis of the ipsilateral soft palate. It is well known that NPC originates commonly from the fossa of Rosenmüller. We therefore hypothesize that the clinical signs of unilateral palate paralysis in patients with NPC must be far more common than usually realized. This issue is, as yet, not fully addressed in the literature. STUDY DESIGN: A prospective study of all patients with newly diagnosed NPC. METHODS: Two hundred sixty-four patients with newly diagnosed NPC were studied. Clinical records included the details of their clinical presentations and the results of physical and neurological examinations. The degree of elevation of the soft palate during phonation was carefully evaluated. Magnetic resonance imaging (MRI) of the head and neck region with a particular emphasis on the levator veli palatini muscles was then performed. The degree of paralysis of the palate was correlated with the degree of invasion of the levator muscles by the tumor, as seen with imaging. The incidence of paralysis of the palate in the patients with NPC was also determined. RESULTS: At the time of diagnosis, ipsilateral paralysis of the palate was observed in 137 (52%) of the 264 patients with NPC. The results of imaging indicated that 62% (163 of 264) of the patients had radiological evidence of tumor invasion of the levator muscle. The degree of paralysis of the palate corresponded well to the extent of tumor invasion of the levator muscle. Paralysis of the palate was not evident in 26 patients with early perimuscular infiltration of the levator muscle. CONCLUSION: This study revealed that ipsilateral invasion of the levator veli palatini muscle by NPC is common and typically presents with signs of unilateral palate paralysis. This subtle sign is relatively common in patients with NPC. Consequently, we think palate function should be routinely tested when diagnosing NPC, particularly when the patient has unilateral aural symptoms or a neck lump.

Three-dimensional imaging of the speaking shunt in patients with near-total laryngectomy.

OBJECTIVES: Near-total laryngectomy with creation of a speaking shunt is generally considered suitable treatment for most T3 and some T4 laryngopharyngeal cancers. In some patients, poor speech production by the shunt can be problematic and usually means that a shunt lumen is stenotic or too small. Conventional axial computed tomography (CT) of the neck is of little value in predicting the shunt function and the patency of the shunt lumen. Such defect, however, can be better overcome if the spiral CT is used. STUDY DESIGN: This study was designed to evaluate the dynamic speaking shunt by spiral CT and a three-dimensional (3-D) imaging model of the upper airway in 59 near-total laryngectomies. METHODS: During scanning, the patients were asked to make a single, 20-second phonation. A high-quality 3-D surface model was then rendered at an independent workstation. The 3-D model took on the appearance of the speaking shunt which could serve as a tracheopharyngeal fistulography. RESULTS: 3-D reconstruction of the images could clearly demonstrate the dynamic anatomy and patency of the speaking shunt. We found the 3-D model to be of diagnostic value, particularly in the near-total laryngectomy patients with stenotic shunts. The most common site of stenosis was at the top portion of the shunt. CONCLUSION: The 3-D image findings of the shunts significantly improved the assessment and therapies of the patients undergoing revision surgeries of the shunt stenoses.