Preoperative three-dimensional model creation of magnetic resonance brain images as a tool to assist neurosurgical planning.

BACKGROUND: Neurosurgeons regularly plan their surgery using magnetic resonance imaging (MRI) images, which may show a clear distinction between the area to be resected and the surrounding healthy brain tissue depending on the nature of the pathology. However, this distinction is often unclear with the naked eye during the surgical intervention, and it may be difficult to infer depth and an accurate volumetric interpretation from a series of MRI image slices. OBJECTIVES: In this work, MRI data are used to create affordable patient-specific 3-dimensional (3D) scale models of the brain which clearly indicate the location and extent of a tumour relative to brain surface features and important adjacent structures. METHODS: This is achieved using custom software and rapid prototyping. In addition, functionally eloquent areas identified using functional MRI are integrated into the 3D models. RESULTS: Preliminary in vivo results are presented for 2 patients. The accuracy of the technique was estimated both theoretically and by printing a geometrical phantom, with mean dimensional errors of less than 0.5 mm observed. CONCLUSIONS: This may provide a practical and cost-effective tool which can be used for training, and during neurosurgical planning and intervention.

Possible role of adjunctive thalidomide therapy in the resolution of a massive intracranial tuberculous abscess.

We present the case of a young child who developed a massive tuberculous abscess of the posterior fossa while being treated for pulmonary tuberculosis. Clinical improvement after surgical excision of the abscess was followed by recurrence of symptoms of acutely raised intracranial pressure on standard antituberculosis and corticosteroid therapy. Magnetic resonance (MR) imaging of the brain showed that a multiloculated abscess had developed anterior to the excision site of the original abscess. The recurring abscess was partly excised and drained but could not be removed completely because of its proximity to the brain stem. Thalidomide, a potent inhibitor of tumour necrosis factor alpha (TNF-alpha), was added to the treatment regimen and resulted in marked clinical improvement with resolution of the abscess within 4 months. The remaining CT lesion had the appearance of a small granuloma. Both the clinical and the radiological response was maintained after 1 year of antituberculosis treatment.

Whole-gut irrigation as a preparation for colorectal surgery.

Whole-gut irrigation was used to prepare 43 patients for colorectal surgery. Antibiotics were used pre-operatively in the first group and added to the irrigation fluid in the second. The condition of the bowel lumen was regarded as perfect or good in 87,2% of cases, and the total sepsis rate was 15,4%. The results are regarded as a significant improvement on conventional methods of bowel preparation.