Spinal cord lesions and clinical status in multiple sclerosis: A 1.5 T and 3 T MRI study

OBJECTIVE

Assess the relationship between spinal cord T2 hyperintense lesions and clinical status in multiple sclerosis (MS) with 1.5 and 3 T MRI.

METHODS

Whole cord T2-weighted fast spin-echo MRI was performed in 32 MS patients [Expanded Disability Status Scale (EDSS) score (mean+/-SD: 2+/-1.9), range 0-6.5]. Protocols at 1.5 T and 3 T were optimized and matched on voxel size.

RESULTS

Moderate correlations were found between whole cord lesion volume and EDSS score at 1.5 T (r(s)=.36, p=0.04), but not at 3 T (r(s)=0.13, p=0.46). Pyramidal Functional System Score (FSS) correlated with thoracic T2 lesion number (r(s)=.46, p=0.01) and total spinal cord lesion number (r(s)=0.37, p=0.04) and volume (r(s)=0.37, p=0.04) at 1.5 T. Bowel/bladder FSS correlated with T2 lesion volume and number in the cervical, thoracic, and total spine at 1.5 T (r(s) 0.40-0.57, all p<0.05). These MRI-FSS correlations were non-significant at 3 T. However, these correlation coefficients did not differ significantly between platforms (Choi's test p>0.05). Correlations between whole cord lesion volume and timed 25-foot walk were non-significant at 1.5 T and 3 T (p>0.05). Lesion number and volume did not differ between MRI platforms in the MS group (p>0.05).

CONCLUSIONS

Despite the use of higher field MRI strength, the link between spinal lesions and MS disability remains weak. The 1.5 T and 3 T protocols yielded similar results for many comparisons.

T2 hypointensity in the deep gray matter of patients with benign multiple sclerosis

Background

Gray matter (GM) magnetic resonance imaging (MRI) T2 hypointensity, a putative marker of iron deposition, commonly occurs in multiple sclerosis (MS). However, GM T2 hypointensity in benign MS (BMS) has not yet been characterized.

Objective

To determine the presence of deep GM T2 hypointensity in BMS, compare it to secondary progressive (SP) MS and assess its association with clinical and diffusion tensor (DT) MRI measures.

Methods

Thirty-five cognitively unimpaired BMS, 26 SPMS patients, and 25 healthy controls were analyzed for normalized T2-intensity in the basal ganglia and thalamus, global T2 hyperintense lesion volume, global atrophy, and white matter and GM DT metrics.

Results

BMS and SPMS patients showed deep GM T2 hypointensity compared with controls. T2 hypointensity was similar in both MS subgroups and moderately correlated ( r = −0.45 to 0.42) with DT MRI metrics. GM T2 hypointensity in BMS showed a weak to moderate correlation ( r = −0.44 to −0.35) with disability.

Conclusions

GM in BMS is not spared from structural change including iron deposition. However, while T2 hypointensity is related to global tissue disruption reflected in DT MRI, the expression of benign versus non-benign MS is likely related to other factors.

Rhodotorula mucilaginosa as a cause of persistent femoral nonunion

We present a case of postoperative infection which presented as nonunion fracture femur in a 30-year-old man due to Rhodotorula mucilaginosa. This is the first report of Rhodotorula infection in a patient with fracture nonunion. The patient underwent repeated surgical debridement and received intensive antibiotic therapy before the diagnosis was made. The diagnosis could have been made earlier if the fungal etiology had been suspected earlier. Early suspicion and diagnosis of infection with atypical yeasts could be under-reported because of difficulties in accurate diagnosis and a tendency of attributing isolates to specimen contamination.

Normal findings on brain fluid-attenuated inversion recovery MR images at 3T

BACKGROUND AND PURPOSE

Fluid attenuated inversion recovery (FLAIR) MR imaging of the brain has become a routine tool for assessing lesions in patients with suspected neurologic disorders. There is growing interest in 3T brain FLAIR MR imaging but little normative data are available. The purpose of this study was to evaluate the frequency and topography of cerebral hyperintensities seen with FLAIR MR imaging of the brain at 3T in a normal population and compare those findings to 1.5T.

MATERIALS AND METHODS

Whole-brain 2D FLAIR MR imaging was performed in 22 healthy controls (mean age, 44 +/- 8 years; range, 30-53 years) at 3T. Fifteen of these subjects also underwent 2D FLAIR at 1.5T, with similar optimized parameters and voxel size. Cerebral hyperintense areas, including discrete foci, anterior and posterior periventricular capping, diffuse parenchymal hyperintensity, septal hyperintensity, corticospinal tract hyperintensity, and CSF flow artifacts were assessed. The Spearman rank test assessed the correlation between discrete hyperintense foci and age. The Wilcoxon signed rank test compared foci detectability at 3T versus 1.5T.

RESULTS

FLAIR at 3T commonly showed hyperintensities such as discrete foci (mean, 10.68 per subject; at least 1 present in 68% of subjects), anterior and posterior periventricular capping, diffuse posterior white matter hyperintensity, septal hyperintensity, corticospinal tract hyperintensity, and ventricular CSF flow artifacts. FLAIR at 3T showed a higher hyperintense foci volume (170 +/- 243 versus 93 +/- 152 mm3, P < .01) and number (9.4 +/- 13 versus 5.5 +/- 9.2, P < .01) than at 1.5T. No significant differences (P = .68) in the length/diameter of individual discrete hyperintense foci were seen between 3T and 1.5T. Discrete foci volume (r = 0.72 at 3T, r = 0.70 at 1.5T) and number (r = 0.74 at 3T; r = 0.69 at 1.5T) correlated with age to a similar degree on both platforms. All discrete foci were confined to the noncallosal supratentorial white matter. The other nonfocal hyperintensities (anterior and posterior periventricular capping, diffuse parenchymal hyperintensity, septal hyperintensity, corticospinal tract hyperintensity, and CSF flow artifacts) were generally more common and prominent at 3T than at 1.5T.

CONCLUSIONS

Discrete and diffuse parenchymal brain white matter FLAIR hyperintensities are more common and prominent at 3T than at 1.5T in healthy volunteers.

Osteomyelitis variolosa: a report of two cases

We present 2 patients with osteomyelitis variolosa in both elbow joints--sequelae of smallpox. The condyles were elongated and the central portions of the distal humeri were absorbed and the elbow joints were unstable. One of the patients sustained a closed fracture of the distal humerus. The fracture united uneventfully following stabilisation and bone grafting. At the 13-year follow-up, the patient had satisfactory elbow function.

Utility of software analysis of esophageal manometry studies in patients with aperistalsis

Esophageal manometry is the gold standard for the diagnosis of esophageal aperistalsis. There is computer software that analyzes peristalsis on esophageal manometry, but this automated analysis has not been formally evaluated. Our primary aim was to evaluate the software analysis of esophageal aperistalsis by esophageal manometry in patients diagnosed with aperistalsis by an experienced clinician. Esophageal manometry studies from January 2006 to November 2007 were retrospectively reviewed for evidence of aperistalsis by an experienced clinician. All studies demonstrating aperistalsis were selected for further review. The automated analysis performed by our software program for each study was recorded. Agreement between the automated analysis and the clinician was measured by the proportion of agreement on the absence of peristalsis. Eighty-seven of the 962 esophageal manometry studies reviewed demonstrated aperistalsis. The automated analysis reported esophageal body peristalsis with wet swallows in 66 out of 87 patients (75.9%). In these patients, the software analyzed an average of 34.2% of the wet swallows as peristaltic. The agreement between the clinician's review and software analysis of aperistalsis was 24.1%. These data suggest there is poor agreement between the automated analysis of peristalsis and that of an experienced reviewer. Automated analysis cannot be relied upon in the diagnostic evaluation of esophageal aperistalsis as it overestimates the presence of peristalsis and may lead to incorrect diagnoses and management strategies.

Solid-pseudopapillary tumour of the pancreas: a report of a rare case

The solid pseudopapillary tumour (SPT) of the pancreas is an uncommon cystic pancreatic neoplasm mostly seen in young females. We present a large SPT in a 16-year-old female who presented with acute onset upper- and mid-quadrant abdominal pain associated with nausea and vomiting for 4 days. The lesion was demonstrated by abdominal ultrasound and by computed tomography, which was successfully removed surgically.

Modulation of AMPA receptor GluR1 subunit phosphorylation in neurons by the intravenous anaesthetic propofol

BACKGROUND

The ionotropic glutamate receptor is a potential molecular site in the central nervous system that general anaesthetics may interact with to produce some of their biological actions. Protein phosphorylation has been well documented to occur in the intracellular C-terminal domain of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) subtype of glutamate receptors, which represents a pivotal mechanism for the post-translational modulation of AMPA receptor functions. In this study, we investigated a possible influence of an i.v. anaesthetic agent propofol on the phosphorylation of AMPA receptor GluR1 subunits in cultured neurons.

METHODS

The effect of propofol on phosphorylation of GluR1 subunits at serine 831 and 845 was assayed in cultured rat striatal and cortical neurons by western blot with phospho- and site-specific antibodies.

RESULTS

Propofol consistently elevated phosphorylation of GluR1 subunits at the C-terminal serine 845 site in both striatal and cortical neurons. The elevation in phosphorylation was concentration-dependent and started at a low concentration (3 microM). This increase in serine 845 phosphorylation was rapid and sustained during the entire course of propofol exposure. In contrast to serine 845, phosphorylation of GluR1 at serine 831 was not altered by propofol in striatal and cortical neurons. Total GluR1 abundance remained unchanged in response to propofol incubation.

CONCLUSIONS

These data indicate that propofol possesses the ability to upregulate AMPA receptor GluR1 subunit phosphorylation at a specific serine 845 site in neurons and provide evidence supporting the AMPA receptor as a molecular target for general anaesthetics.

A novel connexin50 mutation associated with congenital nuclear pulverulent cataracts

PURPOSE

To screen for mutations of connexin50 (Cx50)/GJA8 in a panel of patients with inherited cataract and to determine the cellular and functional consequences of the identified mutation.

METHODS

All patients in the study underwent a full clinical examination and leucocyte DNA was extracted from venous blood. The GJA8 gene was sequenced directly. Connexin function and cellular trafficking were examined by expression in Xenopus oocytes and HeLa cells.

RESULTS

Screening of the GJA8 gene identified a 139 G to A transition that resulted in the replacement of aspartic acid by asparagine (D47N) in the coding region of Cx50. This change co-segregated with cataract among affected members of a family with autosomal dominant nuclear pulverulent cataracts. While pairs of Xenopus oocytes injected with wild type Cx50 RNA formed functional gap junction channels, pairs of oocytes injected with Cx50D47N showed no detectable intercellular conductance. Co-expression of Cx50D47N did not inhibit gap junctional conductance of wild type Cx50. In transiently transfected HeLa cells, wild type Cx50 localised to appositional membranes and within the perinuclear region, but Cx50D47N showed no immunostaining at appositional membranes with immunoreactivity confined to the cytoplasm. Incubation of HeLa cells transfected with Cx50D47N at 27 degrees C resulted in formation of gap junctional plaques.

CONCLUSIONS

The pulverulent cataracts present in members of this family are associated with a novel GJA8 mutation, Cx50D47N, that acts as a loss-of-function mutation. The consequent decrease in lens intercellular communication and changes associated with intracellular retention of the mutant connexin may contribute to cataract formation.

Endocarditis due to Chryseobacterium meningosepticum

Chryseobacterium meningosepticum is a gram negative rod widely distributed in nature. It is known to cause meningitis in neonates and premature infants. Adult infections are not common and are usually nosocomially acquired. We report an unusual case of native valve endocarditis in a 58-year-old man due to this organism. A high degree of suspicion and correct identification and sensitivity testing is required to diagnose infections by this rare isolate.

Health outcome measurements in children with sleep disordered breathing

OBJECTIVE

To validate the Child Health Questionnaire, measure quality of life in children with obstructive sleep apnoea and assess the impact of surgery.

METHODS

The primary carer of a consecutive series of 42 patients with sleep disordered breathing referred to a paediatric otolaryngology clinic completed the Child Health Questionnaire (version PF 28). Questionnaires were analysed for data quality and completeness, item/scale correlation, internal consistency and discriminant validity, interscale correlation and reliability. Following overnight pulse oximetry 37 children were diagnosed with obstructive sleep apnoea and underwent adenotonsillectomy.

RESULTS

Child Health Questionnaire Physical Functioning 28 demonstrated excellent measuring characteristics in our population. Compared with normative data, children with obstructive sleep apnoea and their carers suffer a significant quality of life deficit, involving 10 of 13 subscales of the Child Health Questionnaire. This was most prominent in parental emotional impact, general health perception and family activities. There was no correlation between the severity of obstructive sleep apnoea and quality of life indices. Following surgery, there was a significant improvement in all Child Health Questionnaire subscales, which became equivalent to healthy children.

CONCLUSION

The Child Health Questionnaire Physical Functioning 28 is an accurate and reliable way of assessing the impact of obstructive sleep apnoea on the quality of life in children in Britain. This appears to be significant in most aspects of a child's life, but is fully reversed following surgery.

The oncogenic potential of human papillomaviruses: a review on the role of host genetics and environmental cofactors

Human papillomaviruses (HPVs), with over 100 genotypes, are a very complex group of human pathogenic viruses. In most cases, HPV infection results in benign epithelial proliferations (verrucae). However, oncogenic types of HPV may induce malignant transformation in the presence of cofactors. For example, over 99% of all cervical cancers and a majority of vulval, vaginal, anal and penile cancers are the result of oncogenic HPV types. Such HPV types have been increasingly linked to other epithelial cancers involving the skin, larynx and oesophagus. Although viral infection is necessary for neoplastic transformation, evidence suggests that host and environmental cofactors are also required. Research investigating HPV oncogenesis is complex and quite extensive. The inability to produce mature HPV virions in animal models has been a major limitation in fully elucidating the oncogenic potential and role of associated cofactors in promoting malignant transformation in HPV-infected cells. We have reviewed the literature and provide a brief account of the current understanding of HPV oncogenesis, emphasizing the role of genetic susceptibility, immune response, and environmental and infectious cofactors.

Validation of the Mayo Dysphagia Questionnaire

While multiple instruments characterize upper gastrointestinal symptoms, a validated instrument devoted to the measurement of a spectrum of esophageal dysphagia attributes is not available. Therefore, we constructed and validated the Mayo Dysphagia Questionnaire (MDQ). The 27 items of the MDQ underwent content validity, feasibility, concurrent validity, reproducibility, internal consistency, and construct validity testing. To assess content validity, five esophageal subspecialty gastroenterologists reviewed the items to ensure inclusion of pertinent domains. Feasibility testing was done with eight outpatients who refined problematic items. To assess concurrent validity, 70 patient responses on the MDQ were compared to responses gathered in a structured patient-physician interview. A separate group of 70 outpatients completed the MDQ twice to assess the reproducibility of each item. A total of 148 patients participated in the validation process (78 [53%] men; mean age 62). On average, the MDQ took 6 minutes to complete. A single item (odynophagia) tested poorly with a kappa value of <0.4. Otherwise, the majority of concurrent validity kappa values were in the good to excellent range with a mean of 0.63 (95% CI 0.22-0.89). The majority of reproducibility kappa values were also in the good to excellent range with a median kappa value of 0.76 (interquartile range: 0.67-0.81). Cronbach's alpha values were excellent in the range of 0.86-0.88. Spearman rank correlation coefficients to assess construct validity were also excellent in the range of 0.87-0.98. Thus, the MDQ is a concise instrument that demonstrates overall excellent concurrent validity, reproducibility, internal consistency, and construct validity for the features of esophageal dysphagia.