MRI Inner Ear Imaging and Tone Burst Electrocochleography in the Diagnosis of Ménière's Disease.

OBJECTIVE: To compare the sensitivity of gadolinium MRI inner imaging with tone burst electrocochleography (EcochG) for diagnosing endolymphatic hydrops. STUDY DESIGN: A prospective study on patients who were to have an MRI scan to exclude retrocochlear pathology. SETTING: Tertiary care center. PATIENTS: One hundred and two patients: 57 patients with Possible, Probable, or Definite Ménière's Disease, 25 with asymmetrical hearing loss, 18 with sudden sensorineural hearing loss, and 2 with unilateral tinnitus had additional MRI inner ear imaging and click and tone burst stimulus EcochG testing. INTERVENTION: Diagnostic. MAIN OUTCOME MEASURE: To compare the sensitivity of the two techniques. RESULTS: In 30 patients with symptom-based Definite Ménière's Disease, tone burst EcochG was positive in 25 (83%) and the click EcochG was positive in 9/30 (30%), and gadolinium MRI imaging diagnosed hydrops in 14 (47%). A positive result for either MRI imaging or tone burst EcochG was seen in 26 patients (87%). In 14 subjects with symptom-based Probable Ménière's Disease, 10 (71%) had either a positive EcochG or MRI. In 13 with Possible Ménière's Disease, four (31%) had a positive EcochG or MRI. CONCLUSION: This study confirms the greatly enhanced diagnostic sensitivity of tone burst EcochG over click response in diagnosing endolymphatic hydrops in Ménière's disease. Even though adequate MRI imaging was achieved in 90%, tone burst EcochG was a more sensitive test.

Microcarrier culture for efficient expansion and osteogenic differentiation of human fetal mesenchymal stem cells.

Stirred microcarrier (MC) culture has been suggested as the method of choice for supplying large volumes of mesenchymal stem cells (MSCs) for bone tissue engineering. In this study, we show that in addition to the improvement in cell expansion capacity, MSCs propagated and harvested from MC culture also demonstrate higher osteogenic potency when differentiated in vivo or in vitro in three-dimensional (3D) scaffold cultures as compared with traditional monolayer (MNL) cultures. Cytodex 3 microcarrier-expanded human fetal MSC (hfMSC) cultures (MC-hfMSCs) achieved 12- to 16-fold expansion efficiency (6×10(5)-8×10(5) cells/mL) compared to 4- to 6-fold (1.2×10(5)-1.8×10(5) cells/mL) achieved by traditional MNL-expanded hfMSC culture (MNL-hfMSCs; p<0.05). Both MC-hfMSCs and MNL-hfMSCs maintained similar colony-forming capacity, doubling times, and immunophenotype postexpansion. However, when differentiated under in vitro two-dimensional (2D) osteogenic conditions, MC-hfMSCs exhibited a 45-fold reduction in alkaline phosphatase level and a 37.5% decrease in calcium deposition compared with MNL-hfMSCs (p<0.05). Surprisingly, when MC-hfMSCs and MNL-hfMSCs were seeded on 3D macroporous scaffold culture or subcutaneously implanted into nonobese diabetic/severe combined immunodeficient mice, MC-hfMSCs deposited 63.5% (p<0.05) more calcium and formed 47.2% (p<0.05) more bone volume, respectively. These results suggest that the mode of hfMSC growth in the expansion phase affects the osteogenic potential of hfMSCs differently in various differentiation platforms. In conclusion, MC cultures are advantageous over MNL cultures in bone tissue engineering because MC-hfMSCs have improved cell expansion capacity and exhibit higher osteogenic potential than MNL-hfMSCs when seeded in vitro into 3D scaffolds or implanted in vivo.

Computed tomography assessment of hip joints in asymptomatic individuals in relation to femoroacetabular impingement.

BACKGROUND: Femoroacetabular impingement has become a well-recognized entity predisposing to acetabular labral tears and chondral damage, and subsequently development of osteoarthritis of the hip joint. In the authors' experience, it is common to see bony abnormalities predisposing to femoroacetabular impingement in the contralateral asymptomatic hips in patients with unilateral femoroacetabular impingement. PURPOSE: This study was undertaken to investigate the prevalence of bony abnormalities predisposing to femoroacetabular impingement in asymptomatic individuals without exposing study participants to unnecessary radiation. STUDY DESIGN: Cross-sectional study; Level of evidence, 4. METHODS: Fifty individuals (100 hip joints), ranging from 15 to 40 years of age, who were seen at a local hospital between March and August 2008 with abdominal trauma or nonspecific abdominal pain in whom abdominal computed tomography was performed to aid diagnosis were prospectively studied. These patients were not known to have any history of hip-related problems. Raw data from the abdominal computed tomography scan, performed on a 64-slice multidetector computed tomography scanner, were reformatted using bone algorithm into several different planes. Several measurements and observations of the hip joints were made in relation to femoroacetabular impingement. RESULTS: The 100 hip joints from 50 patients with no history of hip problems demonstrated that 39% of the joints (31% of female, 48% of male joints) have at least 1 morphologic aspect predisposing to femoroacetabular impingement. The majority (66% to 100% ) of the findings were bilateral; 33% of female and 52% of male asymptomatic participants in our study had at least 1 predisposing factor for femoroacetabular impingement in 1 or both of their hip joints. Based on the data collected from this study, the acetabular crossover sign had a 71% sensitivity and 88% specificity for detecting acetabular retroversion. Nonquantitative assessment of the femoral head at the anterior, anterolateral, and lateral head/neck junctions demonstrated that 74% of the joints had an aspherical femoral head. CONCLUSION: The study demonstrated substantial prevalence of bony characteristics predisposing to femoroacetabular impingement in asymptomatic individuals according to the established measurement parameters in current literature.

Hyperintensity in the subarachnoid space on FLAIR MRI.

OBJECTIVE: The purposes of this essay are to illustrate the causes of FLAIR hyperintensity in the subarachnoid space and to outline the mechanisms of the findings. CONCLUSION: FLAIR subarachnoid space hyperintensity may be encountered with both pathological conditions and artifacts. Knowledge of these conditions and appearances coupled with any associated findings may suggest the cause of the FLAIR subarachnoid space hyperintensity. A diffuse distribution and a lack of ancillary findings often remain nonspecific and may require clinical correlation and CSF analysis.

Pneumococcal meningitis masquerading as subarachnoid haemorrhage.

A 43-year-old woman taking warfarin for past venous thrombosis presented with 4 days of flu-like symptoms and deterioration in level of consciousness. Computed tomography suggested subarachnoid haemorrhage, and magnetic resonance imaging showed widespread cerebral infarcts. However, these seemed out of proportion to the amount of haemorrhage, and lumbar puncture revealed meningitis caused by Streptococcus pneumoniae.