Introduction: The treatment of inaccessible cavernomas remains uncertain. Studies indicate Stereotactic Radiosurgery (SRX) reduces the re-bleed rate but some argue that this is the natural history, cavernomas remain visible on MRI scans and the risks of radiation to eloquent areas are unjustified when the treatment is unproven. Surgery whilst definitive is not without risk and others argue SRX is still a safer option. Immediate views on MRI with gadolinium shows variable enhancement of cavernomas. Because cavernomas are considered to be extremely low flow lesions it was hypothesized that delayed images after contrast would reveal their true nature. There are no studies on immediate and delayed enhancement of cavernomas in the literature.
Methods: Pre-gadolinium, Immediate Post-gadolinium and 20-40 minute Delayed Post-gadolinium enhanced MRI scans were performed in 13 patients with 18 cavernomas between 2003-2012. There were 8 females and 5 males aged between 14-61 years. 7 patients had cavernomas in the brainstem, 3 in deep locations, 6 in the supratentorial compartment, none in the infratentorial compartment and 2 had them in the spinal cord. The presentations were with events, hemorrhages, seizures, an increase in size or the cavernomas were incidental. The treatment was multimodal.
Results: Seven cavernomas did not enhance at all. Also, there were no cavernomas which did not enhance on the immediate study but then enhanced on the delayed views. One cavernoma which enhanced on the immediate study then waned in appearance on the delayed study. Four cavernomas enhanced on the immediate views and remained the same on the delayed studies and in fourteen cavernomas the enhancement present on the immediate studies increased further on the delayed views.
Conclusions: Cavernomas demonstrate a variable pattern of enhancement on Delayed studies. The test could assist in understanding their natural history, allow an assessment of operative interventions and permit evaluation of the effects of SRX.
Patient Care: (1) It will assist in pre-operative identification and post-operative resections of cavernomas, (2) it will establish whether SRX has an effect on cavernomas once and for all, (3) it will permit a study of the natural history of cavernomas and from their patterns of enhancement be able to predict the risk of hemorrhage (4) and thus dictate the management of these.
Learning Objectives: The participants should (1) understand the impact of this study, (2) realize that contrast enhancement to delineate flow in cavernomas can be studied, (3) appreciate its use and importance in pre-operative identification and post-operative resections, (4) be able to study the effects of SRX and determine if it is efficacious, (5) study the natural history and predict which cavernomas are more likely to bleed from their patterns of enhancement (6) and thus, monitor/treat them.