ABSTRACT
Purpose: Brain abscesses often present an aetiological dilemma. Microscopy is insensitive and culture techniques are time consuming. Hence, a new rapid technique in vitro Proton Magnetic Resonance Spectroscopy ( 1 HMRS) was evaluated for its usefulness in the identification of aetiology of brain abscesses. Materials and Methods: A total of 39 pus specimens from brain abscesses were subjected to in vitro 1 HMRS. These pus specimens were also processed by conventional culture methods. The spectral patterns generated by in vitro 1 HMRS were further correlated with culture results. Results: Pus specimens which showed the presence of anaerobes on culture revealed the presence of multiplet at 0.9 ppm (100%), lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (100%) and succinate at 2.4 ppm (75%). Pus specimens that revealed the presence of facultative anaerobes on culture showed a pattern B, i.e., the presence of lactate-lipid at 1.3 ppm (100%), acetate at 1.92 ppm (88.88%) along with the multiplet at 0.9 ppm (100%). Pattern C was seen in aerobic infection which showed the presence of lactate-lipid at 1.3 ppm (100%) along with the multiplet at 0.9 ppm. Pus from two tuberculous abscesses showed the complete absence of multiplet at 0.9 ppm. Conclusions: We observed in this study that it was possible to differentiate bacterial and tuberculous brain abscesses using in vitro 1 HMRS. Further, it was also possible to distinguish between aerobic and anaerobic brain abscesses on the basis of spectral patterns. In vitro 1 HMRS of fungal and actinomycotic brain abscess are also presented for its unusual spectra.
ABSTRACT
In this retrospective study 100 patients of pituitary adenoma who underwent Trans-septal Trans-sphenoidal surgery over 10 years period were evaluated. The mean presenting complaints of these patients were headache and decreased vision. Majority of tumors in our study were non functioning adenomas (39%) followed by prolactinomas (38%), growth hormone producing tumors constituted 20%, where as cortisol secreting adenomas were 3%. There was no operative mortality in our series. Post-op CSF rhinnorrhoea was noted in 3 patients - out of these one patient required surgical repair of fistula in immediate postoprated period while other two patients were managed with lumbar drain. Total excision of tumor was attained in 38% of patients as these were evaluated by post-oprated CT scan and MRI with contrast. 30% of patients were given radiotherapy immediately after the surgery. These were patients in whom residual tumor was more than 1 cm in size and the hormone levels did not return to normal. The patients were followed up from 9 months to 10 years with a mean follow up of 4 years. There were total of 18 recurrences on follow up study.
ABSTRACT
PURPOSE: The non-sporing anaerobes cause a wide spectrum of infections. They are difficult to culture and their identification is tedious and time-consuming. Rapid identification of anaerobes is highly desirable. Towards this end, the potential of nuclear magnetic resonance (NMR) spectroscopy for providing a fingerprint within the proton spectrum of six genera belonging to anaerobes reflecting their characteristic metabolites has been investigated. METHODS: NMR analysis was carried out using Mercury plus Varian 300 MHz (7.05 T) NMR spectrophotometer on six different anaerobes. These included Bacteroides fragilis, Prevotella melaninogenica, Prevotella denticola, Fusobacterium necrophorum, Peptococcus niger and Peptostreptococcus spp. After the NMR analysis (256/512 scans), the different peaks were noted. The eight pus specimens, which yielded pure culture of anaerobe, also were analysed similarly. RESULTS: The major resonances of multiplex of amino acids/lipid at 0.9 ppm along with lactate/lipid at 1.3 ppm, acetate at 1.92 ppm and multiplex of lysine at 3.0 ppm remained constant to label the organism as an anaerobe. There was a difference found in the MR spectra of different genera and species. A simple algorithm was developed for the identification of the six different anaerobes studied. The MR spectra of the pure culture of the organism matched the MR spectra of pus from which the organism was isolated. CONCLUSIONS: MR-based identification was of value in the identification of anaerobes. However, a larger database of the peaks produced by anaerobes needs to be created for identification of all genera and species. It could then have the potential of diagnosing an anaerobic infection in vivo and thus expedite management of deep-seated abscesses.