Cortical and subcortical T2 shortening in multiple sclerosis.

Low signal intensity on long-repetition-time MR sequences has been observed in deep gray matter structures in patients with multiple sclerosis. This T2 shortening most likely represents a nonspecific degenerative process. We recently observed T2 shortening in the pericentral cortical gray matter and subcortical white matter in a patient with severe multiple sclerosis and we postulate that this represents an additional manifestation of neural degeneration.     

Magnetic resonance imaging of third cranial nerve palsy and trigeminal sensory loss caused by herpes zoster.

A 44-year-old man with right-sided herpes zoster ophthalmicus (HZO) developed ipsilateral third and sixth cranial nerve palsies and first-division trigeminal (fifth cranial nerve) sensory loss. MRI revealed contrast enhancement of the cisternal and cavernous portions of the third cranial nerve and high signal on a FLAIR sequence within the ipsilateral medulla at the presumed location of the trigeminal nucleus and tract. To our knowledge, this is the first report of the combination of these imaging findings in HZO.     

The ostiomeatal unit and endoscopic surgery: anatomy, variations, and imaging findings in inflammatory diseases.

Recent and ongoing advances made in endoscopic surgical techniques require the radiologist to understand the anatomy and pathophysiology of the paranasal sinuses and nasal passage. Endoscopy and CT are complementary procedures, and, as such, the normal anatomic relationships and their CT appearances need to be well understood in order for radiologists to offer continued support as consultants to their clinical colleagues. In this article, we review the pertinent anatomy of the lateral nasal wall and paranasal sinuses, discuss the most frequently encountered normal variations that may predispose a patient to inflammatory sinus disease, outline imaging protocols for evaluation of this region, and introduce the reader to current endoscopic surgical techniques. Last, the imaging findings in various inflammatory processes involving the sinuses, as well as the local and regional complications associated with paranasal sinus inflammatory diseases, are presented.     

MR appearance of trigeminal and hypoglossal motor denervation.

PURPOSETo illustrate and describe the appearance of both long-standing and relatively recently occurring motor denervation of the hypoglossal nerve and of the third (mandibular) division of the trigeminal nerve (V3), with emphasis on findings particular to MR imaging.METHODSFindings from 11 patients with V3 denervation and from seven patients with hypoglossal denervation resulting from a variety of abnormalities were reviewed retrospectively. The motor denervation appearance and functional compromise of the affected musculature are described in terms of the chronicity of the denervation process.RESULTSThe appearance of V3 and hypoglossal motor denervation varies with the chronicity of the process. Long-standing denervation results in extensive fatty replacement and a decrease in the size of the affected musculature. Relatively recently occurring denervation results in abnormal contrast enhancement and edemalike signal changes in the denervated musculature. Fatty replacement was observed acutely in hypoglossal denervation but did not manifest until the subacute stage in V3 denervation. Increased volume of the denervated musculature may also accompany acute denervation signal changes.CONCLUSIONV3 and hypoglossal denervation have a variable appearance depending on the chronicity of the process. Recognition of MR imaging patterns of denervation may allow earlier diagnosis of a denervating lesion and may help to distinguish denervation from similar-appearing processes, such as infection or neoplasia.     

Picotamide inhibition of excess in vitro thromboxane B2 release by colorectal mucosa in inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.     

Atypical skull base paragangliomas.

We present two cases of unusually large skull base paragangliomas. The first tumor was accompanied by marked bony destruction of the central skull base and multiple associated cysts. The second tumor arose along the petrous ridge, with a large intracranial component. The CT, MR imaging, angiographic, histologic, and electron microscopic findings of these unusual lesions are described.     

Hydrosalpinges adversely affect markers of endometrial receptivity

While in-vitro fertilization (IVF) was initially developed in women with tubal factor infertility, recent clinical studies have suggested that the presence of hydrosalpinges lowers implantation and pregnancy rates. We postulated that these hydrosalpinges cause impaired endometrial receptivity. A total of 103 women with hydrosalpinges were prospectively evaluated, and compared with 55 infertile and 44 fertile controls. All women had endometrial biopsies during the window of implantation, analysed by conventional histological criteria, and also stained for three integrin markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha vbeta3). Women with hydrosalpinges (cases) expressed significantly less of the alpha vbeta3 integrin compared with controls. There was no difference in expression of alpha1beta1 or alpha4beta1 among groups. A significantly greater number of cases had out of phase histology and missing alpha vbeta3 (type I defects) and absent integrin expression despite normal histological maturation (type II) defects, compared with controls. Of 20 women with impaired endometrial receptivity who were also biopsied after hydrosalpinx surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven percent of type I and 57% of type II defects were corrected postoperatively. Using markers of endometrial receptivity, this study demonstrates that inflammatory hydrosalpinges have an adverse effect on endometrial receptivity, which in some cases may be overcome by surgical treatment of the hydrosalpinx.