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E Fritzsche

Publications and source records attributed to E Fritzsche.

4 recordsLinked to original sources
PubMed2003

[Intraoperative ultrasound of intra- and extramedullary tumours].

AIM: Spinal tumours can be diagnosed precisely by magnetic resonance imaging (MRI). Planning the surgical procedure of intradural tumours, intraoperative ultrasound (IOUS) has been used to evaluate its diagnostic potential. METHOD: From 1997 to 9/2002 32 patients with the diagnosis of an ependymoma (n = 9), astrocytoma (n = 5), haemangioblastoma (n = 5), neurinoma (n = 4), meningeoma (n = 4) and filum terminale ependymoma (n = 5) were investigated by intraoperative transdural sonography. The sonographic results were correlated to the preoperative MRI-findings and histopathological work-up. RESULTS: Intramedullary tumours characteristically present with a heterogenous morphology, sometimes carrying intralesional or perilesional cysts. The tumour margins are frequently poorly defined, and there is a perifocal oedema. Extramedullary tumours frequently display a homogenous signal intensity, well defined tumour margins and the abscence of perifocal oedema. Haemangioblastomas turned out to be a specific sonographic entity among intramedullary tumours, as they most often contain only a cystic part with a small tumour nodule. IOUS influenced the surgical approach as laminotomy has to be extended in 7/32 cases to reach the tips of the tumour. CONCLUSION: The precision of surgical exposure of intradural spinal lesions can be optimised by IOUS which shows a high correlation with MRI characterizing extra- and intramedullary tumours. Using IOUS, the exact position of the laminectomy/laminotomy can be adapted to the true extent of the tumour, thus avoiding the necessity of further bone work in the case of the frequently oedematous spinal cord protruding through the opening in the dura. Overall, IOUS guidance can help to reduce postoperative morbidity in surgery for all spinal intradural lesions.

Astrocytoma↗
PubMed1987

The use of permanganate as a sequencing reagent for identification of 5-methylcytosine residues in DNA.

The use of permanganate as a reagent for DNA sequencing by chemical degradation has been studied with respect to its specificity for 5-methylcytosine residues. At weakly acidic pH and room temperature, 0.2 mM potassium permanganate reacts preferentially with thymine, 5-methylcytosine, and to a lesser extent with purine residues, while cytosine remains essentially intact. Permanganate oxidation is, therefore, a suitable DNA sequencing reaction for positive discrimination between 5-methylcytosine and unmethylated cytosine.

5-Methylcytosine↗