In a shot injury of the brain there are tissue crush injuries and – more peripherally from them – progressively diminishing tears seen in the vicinity of the shot canal. Still more peripherally, an apparently undamaged tissue follows these zones but the histology always reveals that perivascular haemorrhages into so called Virchow – Robin spaces, smaller but sometimes even relatively large ones are present there. What is, however, very conspicuous is a presence of these haemorrhages diffusely in the whole brain, not only in an immediate vicinity of a shot canal. 43 cases of a fatal bullet wound of the brain were selected out of 21 156 forensic autopsies, performed in our Institute of Forensic Medicine in past ten years. In all these cases the death was caused by a single non-fragmented bullet, made out of lead or a fully metal jacketed one. An instant death always followed. Without any exception, in all cases there were haemorrhages into perivascular spaces in all examined samples of the brain, varying from several erythrocytes up to much larger ones, encircling the blood vessel in a cufflike pattern. Haemorrhages in an immediate vicinity of a shot canal can be explained by a direct bleeding from the damaged tissue. Nevertheless, more peripherally placed haemorrhages are formed by a different mechanism. Sudden changes of pressure, caused by penetration of the bullet through tissues, are transported to blood vessels and the energy of a shock wave is hence spread to the periphery too. The first phase of mentioned pressure changes is characterized by a very steep increase of blood pressure in a vessel. Rupture of the vessel wall follows if its resistance cannot sustain it and perivascular haemorrhages are thus formed. These perivascular haemorrhages are developed almost instantly as also the deaths of shot persons were instant. It is very probable that similar perivascular haemorrhages, diffusely distributed in the whole brain are also formed in persons, who survive the same shot injury. In all these individuals it seems necessary not to overlook possible neurological damages caused by this complex mechanism.

        Key words: shot wound, cerebral trauma, perivascular haemorrhages, Virchow-Robin spaces