Reversible ischemia around intracerebral hemorrhage: a single-photon emission computerized tomography study.

OBJECT: A zone of perilesional ischemia has been demonstrated around intracerebral hemorrhage (ICH) in numerous experimental models and in human studies. There is potential for perfusion recovery in the zone of perilesional oligemia around ICH. The authors sought to demonstrate, quantify, and study the chronological evolution of perilesional ischemic change in ICH in humans by measuring cerebral blood flow. METHODS: Eleven patients with spontaneous supratentorial ICH underwent two technetium-99m hexamethylpropyleneamine oxime single-photon emission computerized tomography (SPECT) scanning, one in the acute stage (within days of ictus) and the other in the late stage (6-9 months postictus). All patients in this study were treated nonsurgically. Methods of SPECT data analysis based on count differences in regions of interest can be difficult to apply to images with large space-occupying lesions such as ICH, because of the distortion of intracranial anatomy, midline shift, and alterations in the three-dimensional (3D) characteristics of the lesion over time (that is, absorption of the hematoma on the later studies). The authors used the following method: the late and early images were registered and aligned to a common 3D orientation and were normalized to maximal counts. The late images were then compared voxel by voxel with the early ones. The region-growing algorithm was used to discern the difference between the two images, outlining voxels in the perihematoma region, with a signal improvement of at least 15% on the late image. Discrete brain regions around the hematoma with at least a 15% improvement in radiotracer uptake (and hence perfusion) in the late images were observed in all cases. The mean volume of brain with a greater than 15% improvement in perfusion between the two studies was 34.8 cm3 (range 7.2-71.3 cm3). These volumes represent regions of the brain that were poorly perfused in the initial studies. This may represent a zone of reversible perilesional oligemia (penumbra) in ICH in humans. CONCLUSIONS: This is the first study in which it is documented that some of the perilesional hypoperfused tissue around human ICH regains its perfusion in the long term, leading the authors to suggest that there may be a penumbra in human ICH. Medical or surgical therapeutic interventions could increase the volume of perilesional brain that recovers after the initial insult. The results of this study therefore support the concept that intervention in ICH has the potential to reduce the ultimate neurological deficit and improve outcome.

Comparative study of traumatic and spontaneous intracerebral hemorrhage.

OBJECT: Spontaneous intracerebral hemorrhage (SICH) and traumatic intracerebral hemorrhage (TICH) are common disorders. The authors planned to study how these two types of hemorrhage behave pathologically and clinically to gain further insight into their causes, pathogeneses, indications for surgical intervention, and prognoses. METHODS: Prospectively filled databases of demographic, clinical, radiological, and outcome details have been maintained for all patients admitted to the Regional Neurosciences Centre with head injury since 1987 and with SICH since 1993. Of the 5686 patients whose case information was included in the head-injury database, 90 were found to suffer from an isolated intracerebral hemorrhage (ICH) as the only major abnormality observed on computerized tomography scans (subdural and extradural hematomas were excluded). Case details on these 90 patients and the 440 patients from the SICH database were extracted and analyzed using a statistical software program. The median age of patients with TICH was lower than the median age of patients with SICH (51 years compared with 65 years, respectively), but it was much higher than the median age of the entire head-injury group (21 years). Among patients younger than 45 years of age, 0.8% of patients who experienced trauma suffered from an ICH compared with 4.3% of patients older than 45 years of age. Irrespective of intervention, much better outcomes were achieved by patients with TICH compared with those with SICH (67% favorable outcomes compared with 24% in patients with SICH). Following trauma, there was no significant relationship between the severity of injury and the development of ICH. At presentation the median Glasgow Coma Scale (GCS) score for both groups was 13. Younger age and higher GCS score at presentation were strongly related to a favorable outcome for both types of hemorrhage. There was no significant difference in patient age, presenting GCS score, or outcomes of patients who underwent surgery compared with those who did not for either type of hemorrhage. No conclusions can be drawn about the efficacy of surgery from such observational studies. CONCLUSIONS: On the basis of these data the authors suggest that TICH and SICH have different features: TICH affects a slightly younger age group and carries a much better prognosis compared with SICH. In addition, indications for surgical intervention are not well defined for either type of hemorrhage. Practice is subjective and inconsistent. The International Surgical Trial in Intracerebral Haemorrhage may resolve the dilemma for SICH. A similar trial in which surgery is compared with conservative management should be considered for cases of TICH.