Giovanni Marini

Intraventricular Morphine in Paraneoplastic Painful Syndrome of the Cervicofacial Region: Experience in Thirty-eight Cases

The authors report their personal experience with the administration of microdoses of morphine hydrochloride by the intraventricular route through a subcutaneous reservoir for the treatment of paraneoplastic painful syndrome of the cervicofacial region in 38 patients. The results obtained are very encouraging.

Brain Stem Expanding Lesions: Stereotactic Diagnosis and Therapeutical Approach

In most cases of brain stem expansive lesion a surgical approach is possible, but in each patient it must be evaluated if the surgical risk is proportional to the therapeutic result. Sometime surgery is limited to a biopsy sample, particularly in malignant lesions. We started stereotactic serial biopsy sampling in all CT or NMR intraaxial brain stem expansive lesions as a preliminary diagnostic procedure. The aim is to look for benign well delimited lesions that we consider for surgical removal or to drain haematomas and abscesses. 35 patients with brain stem expansive lesions were submitted to 47 surgical procedures: 35 stereotactic biopsies (one each patient) and, among them, 12 were major surgical procedures (with craniotomy) for microsurgical removal of the expansive lesions. 15 patients were in paediatric age. Suboccipital transcerebellar approach was performed in 25 mesencephalic, pontine, bulbar expansive lesions and frontal approach was limited to 10 thalamo-mesencephalic lesions. There was no mortality. Two patients were stereotactically drained and definitively cured.

Brain stem expansive lesions: stereotactic biopsy for a better therapeutic approach.

CT diagnosed brain stem malignant lesions were in the past almost always treated with radiation therapy (RT). Eventually this turned out to be a grave mistake. With stereotactic serial biopsies of all brain stem expanding lesions we have been able to verify the histological nature in all cases but two and to prevent a blind therapeutic approach. In 24 patients bearing CT diagnosed expansive lesions into the brain stem 68 samples were taken during 24 stereotactic procedures. In 8 patients surgical removal of the expanding lesion was attempted after stereotactic biopsy.

Open Stereotactic Neurosurgery: 57 Cases

The two main neurosurgical tools are the operative microscope and stereotactic apparatus. The operative microscope is essential in cisternal or ventricular surgery and the stereotactic apparatus is essential in approaching intracerebral lesions. Both given their best performance when the one aids the other. Small convexity lesions are best approach with stereotactic aid, and excellent microsurgical intracerebral lesions can be debulked with the operative microscope. Malignant tumours pursue their inevitable course but slow growing tumours and angiomas may have long survival even with one subtotal removal. The major problem in removing slow-growing tumors is the difficulty in distinguishing tumour from normal brain, but the stereotactic guide is useful in delimitating tumour volume. The results in 57 cases are described.

Stereotactic Approach in Brain Tumors

The stereotactic approach to intracranial expansive lesions is to be considered complementary to the traditional “free hand” surgery. With both techniques it is possible to explore or remove any kind of lesion sited everywhere into the cranial space. When an intraparenchimatous lesion is to be approached the only help to the surgeon is the possibility to distinguish normal from pathological tissue. This is not always possible. A surgical approach with the stereotactic frame not only helps to guide exactely the position of the surgical instrument into the tumor, but also to recognize the volume of the lesion when removal is acheavable (open-stereotaxis). 362 (26%) out of 1385 patients with intracranial expansive lesions were approached with stereotactic guide from May 1983 to May 1990. In 96% of these patients serial stereotactic samples were sufficient to reach an histopathological diagnosis. The most important result is that about 20% of all patients had not neoplasms, 35% had slow growing tumors and 45% had fast growing or malignant tumors. Stereoguided histopathology helps in making decision for a more adequate further treatment.

Stereotactic Computer Graphic System with Brain Maps

We have developed a stereotactic computer graphic system with brain maps that runs on a personal computer. This system consists of three parts: 1. firmware for dizitizing radiological films with a TV camera or scanner (when digital image is not directly obtained from floppy disks); 2. software for introducing or processing brain maps by matching them with CT or NMR images; 3. hardware. Our system is designed to: 1. recognize the relevant frame points and calculate targets, their volume and surgical instrument trajectory; 2. match between brain maps of an ideal brain and patients CT or NMR images with visible and invisible pathology; 3. monitor during surgery the position of the surgical instrument or target modification. The whole procedure and processed images are stored in a data-base for further study.