A diagnostic test for Ménière's Disease and Cochlear Hydrops: impaired high-pass noise masking of auditory brainstem responses.

HYPOTHESIS: Endolymphatic hydrops in patients diagnosed with Ménière's disease causes changes in the response properties of the basilar membrane that lead to impaired high-pass noise masking of auditory brainstem responses to clicks. BACKGROUND: Ménière's disease is defined as the idiopathic syndrome of endolymphatic (cochlear) hydrops, which is an abnormal increase in the volume of cochlear fluid (endolymph) in the inner ear. Accurate detection and diagnosis are important but difficult because of the lack of sufficiently sensitive tests. METHODS: Two populations were compared: (1) 38 non-Ménière's normal-hearing subjects; and (2) 23 patients who, at the time of testing, continued to have at least three of the four hallmark symptoms (i.e., tinnitus, vertigo, fluctuating hearing loss, and fullness) used in the diagnosis of Ménière's disease. Auditory brainstem responses to clicks presented ipsilaterally with masking noise that was high-pass filtered at various frequencies were recorded. RESULTS: In the Ménière's patients, the masking noise is insufficient such that an undermasked Wave V is still present at a latency similar to that of Wave V in the response to the clicks alone. In the control non-Ménière's normal-hearing subjects, this undermasked component was either absent or significantly delayed because of the masking noise. The difference in the delays between these populations is such that the distributions do not overlap, resulting in 100% sensitivity and 100% specificity. CONCLUSION: This test is able to distinguish objectively active Ménière's disease in individuals and may show promise for tracking changes in the severity of the disease caused by progression or treatment.     

An infiltrative variant of non-neural granular cell tumor: a case report

Dermal non-neural granular cell tumors are rare tumors of indeterminate lineage that typically present as well-circumscribed tumors with nuclear pleomorphism and mitotic activity. We describe a dermal non-neural granular cell tumor with a distinctive growth pattern with granular cells interspersed between collagen bundles. This asymptomatic papule arose on the scapula of a 46-year-old woman and consisted of a mixture of epithelioid and spindled granular cells. The immunohistochemical characteristics were similar to those of previously reported dermal non-neural granular cell tumors. Despite mild nuclear pleomorphism and dispersion of lesional cells among collagen bundles, mitoses were not present and Ki-67 staining indicated a low proliferative rate. In addition to being S-100 protein negative and NKI/C3 positive, our case was positive for PGP9.5 and weakly positive for neuron-specific enolase, a staining pattern similar to what has been observed for cellular neurothekeomas. Our case could represent a dermal non-neural granular cell tumor with unique architecture, a granular cellular neurothekeoma or a granular cell dermatofibroma. As both dermal non-neural granular cell tumor and cellular neurothekeoma are of indeterminate lineage, our case with features characteristic of both entities may suggest a common precursor or lineage for dermal non-neural granular cell tumor and cellular neurothekeoma.     

Vitamin D receptor, oestrogen receptor-alpha and calcium-sensing receptor genotypes, bone mineral density and biochemical markers in Paget's disease of bone

OBJECTIVES: The significance of genetic polymorphisms in the development of Paget's disease of bone is unclear at present. METHODS: We analysed the BsmI polymorphism of the vitamin D receptor (VDR) gene, the PvuII and XbaI polymorphisms of the oestrogen receptor-alpha (ER alpha) gene, and the A986S polymorphism of the calcium-sensing receptor (CaSR) gene in 69 pagetic patients and 120 healthy subjects. We also examined the relationship of these polymorphisms with lumbar spine and femoral neck BMD as well as with biochemical parameters (serum alkaline phosphatase, osteocalcin and parathyroid hormone) in Paget's disease. RESULTS: The XbaI and PvuII genotype distributions of the ER alpha gene were significantly different between patients with Paget's disease and control subjects (P<0.001). Also, the CaSR A986S genotype frequency was significantly different between pagetic patients and controls (P<0.01). No significant effect of gene polymorphisms on BMD or biochemical parameters of bone turnover was observed. CONCLUSION: Our results suggest that the ER alpha PvuII/XbaI and CaSR A986S polymorphisms may contribute to genetic susceptibility to Paget's disease. However, further studies are required to investigate the underlying pathomechanism and to replicate the associations.     

Assessment of myocardial viability by nuclear imaging techniques

The assessment of myocardial viability has become important in the diagnostic and prognostic work up of patients with ischemic cardiomyopathy. Patients with viable myocardium may benefit from revascularization in terms of improvement of function, symptoms, and prognosis. In contrast, patients without viable myocardium do not benefit and should be treated conservatively. Various nuclear imaging techniques are available.