Jan Kastner

Diffusion tensor magnetic resonance imaging of glial brain tumors

AIM To evaluate the authors experience with the use of diffusion tensor magnetic resonance imaging (DTI) on patients with glial tumors. METHODS A retrospective evaluation of a group of 24 patients with glial tumors was performed. There were eight patients with Grade II, eight patients with Grade III and eight patients with Grade IV tumors with a histologically proven diagnosis. All the patients underwent routine imaging including T2 weighted images, multidirectional diffusion weighted imaging (measured in 60 non-collinear directions) and T1 weighted non-enhanced and contrast enhanced images. The imaging sequence and evaluation software were produced by Massachusetts General Hospital Corporation (Boston, MA, USA). Fractional anisotropy (FA) maps were calculated in all patients. The white matter FA changes were assessed within the tumorous tissue, on the tumorous borderline and in the normally appearing white matter adjacent to the tumor. A three-dimensional model of the white matter tract was created to demonstrate the space relationship of the tumor and the capsula interna or corpus callosum in each case using the following fiber tracing parameters: FA step 0.25 and a tensor declination angle of 45 gr. An additional assessment of the tumorous tissue enhancement was performed. RESULTS A uniform homogenous structure with sharp demargination of the Grade II tumors and the wide rim of the intermedial FA in all Grade III tumors respectively, were found during the evaluation of the FA maps. In Grade IV tumors a variable demargination was noted on the FA maps. The sensitivity and specificity for the discrimination of low- and high-grade glial tumors using FA maps was revealed to be 81% and 87% respectively. If the evaluation of the contrast enhancement was combined with the evaluation of the FA maps, both sensitivity and specificity were 100%. CONCLUSION Although the evaluation of the fractional anisotropy maps is not sufficient for glioma grading, the combination of the contrast enhancement pattern and fractional anisotropy maps evaluation improves the possibility of distinguishing low- and high-grade glial tumors. Three-dimensional models of the white matter fibers in the corpus callosum and the internal capsule may be used in the presurgical planning.

Complete Binasal Hemianopsia

The authors describe a case study of a 21-year-old female patient suffering from a tumour in the pineal region and dorsal part of the 3rd cerebral ventricle (pineocytoma) who developed complete binasal hemianopsia 11 months after the tumour’s removal. These perimetric changes did not show any progression for seven years. In discussing the question of the pathogenesis of hemianopic defects, the authors are inclined to the opinion that both of the optic nerves are compressed by the circle of Willis vessels.

Orbital and Intracranial Complications of Acute and Chronic Rhinosinusitis

Orbital and intracranial complications are uncommon but potentially serious events that may occur in previously healthy patients with acute or chronic rhinosinusitis, although they occur more frequently when infections are severe or the patient is immunocompromised. Orbital complications include preseptal and postseptal complications, i.e. orbital cellulitis and subperiosteal and intraorbital abscess. Intracranial complications include epidural or subdural abscesses, brain abscess, meningitis, encephalitis and superior sagittal and cavernous sinus thrombosis. The onset of rhinosinusitis complications may vary during the course of disease. Presenting symptoms indicative of complications include periorbital oedema, displaced bulb, double or reduced vision, ophthalmoplegia, severe frontal headache, frontal swelling, signs of meningitis, focal neurological signs or systemic signs (intracranial). On presentation, the clinician must be aware of the potential severity of complications and perform urgent investigations and intervention. The appropriate imaging methods (CT or MRI) should be performed if complications are suspected, even in the face of previously negative CT scans or previously absent symptomatology. When evaluating rhinosinusitis complications, an MRI is generally the preferred approach compared to CT scanning. Intervening treatment measures may mask the severity of an infectious complication suggesting the need to thoroughly evaluate any evidence of extension of an infections beyond the confines of the paranasal sinuses. Diagnostic endoscopy of the nose and upper airway tract using a flexible endoscope is also an option to diagnose complications. A multidisciplinary approach may be required in managing orbital or intracranial abscess formation. Management of complications may include conservative measures and/or surgical drainage. Endoscopic surgery is preferred over the external approach in surgical drainage of predisposing rhinosinusitis. Complications of rhinosinusitis may lead to significant morbidity and mortality. Early diagnosis and proper treatment of the underlying inflammation process as well as management of complications are crucial components in the management of rhinosinusitis.

Fragment analysis of chromosomal region 3q25.31–3q28 in HNSCC

Abstract Problem: Amplification of chromosome 3q has been implicated to contribute to the genesis of head and neck squamous cell carcinoma (HNSCC). Here we targeted the question of whether early (small) chromosomal changes are detectable in the tumor and macroscopically normal surrounding mucosa by fragment analysis. Therefore we conducted fragment analysis of chromosomal region 3q26 and surrounding regions. Methods: From 20 patients biopsies of the primary tumors and adjacent mucosa and at 1 cm and 2 cm from the tumor border were collected. Eleven microsatellite markers at loci 3q25.31–3q28 were amplified and analyzed by capillary electrophoresis. Results: We confirmed high ratios of gains in the samples as previously observed by Comparative Genomic Hybridization (CGH), which we called in analogy to losses, GOH (gain of heterozygosity or amplification of 1 microsatellite allele). We found GOH in tumor samples as well as high ratios of GOH (up to one third of all informative allelotypes) in adjacent macro- and microscopically normal mucosa. Conclusion: The results indicate that the term “molecular dysplasia” should be introduced for preneoplastic processes that are not detectable by conventional histopathological examination. Significance: As we detected by fragment analysis small aberrations in noncancerous (dysplastic or normal) mucosa adjacent to the tumor, we propose that these loci harbor one or more oncogenes that might be relevant in early carcinogenesis in HNSCC. Our data suggest further molecular studies to identify mechanisms of early carcinogenesis in HNSCC. Support: None reported.