ABSTRACT
Serial single photon emission computed tomography (SPECT), near-infrared spectroscopy (NIRS), and transcranial doppler (TCD) sonography examinations were performed to investigate changes of cerebral perfusion and tissue oxygenation in a patient with complicated cerebral malaria that have been acquired in Nigeria. On admission to the Neurologic Intensive Care Unit in Innsbruck, Austria, SPECT and NIRS revealed focal right hemispheric hypoperfusion and decreased oxygen saturation, respectively, correlating exactly to the patient's right hemispheric localizing signs. In contrast, TCD examinations of the basal cerebral vessels revealed normal flow patterns. The patient showed an initial Plasmodium falciparum parasitemia rate of 30% and was cured by intravenous quinine and oral mefloquine therapy. He was discharged without neurologic symptoms. Follow-up SPECT and NIRS examinations revealed regular cerebral perfusion and oxygenation patterns in both cortical hemispheres. In summary, the presented findings provide first evidence that noninvasive SPECT and NIRS may be important diagnostic tools in the evaluation of impaired cerebral microcirculation in patients with P. falciparum malaria.
Subject(s)
Cerebrovascular Circulation , Malaria, Cerebral/physiopathology , Oxygen/metabolism , Spectroscopy, Near-Infrared , Tomography, Emission-Computed, Single-Photon , Adult , Brain/blood supply , Brain/metabolism , Echoencephalography , Humans , Malaria, Cerebral/metabolism , Male , Microcirculation , Prospective StudiesABSTRACT
Near infrared spectroscopy (NIRS) was used to asses changes in regional cerebral oxygen saturation (rSO2) in 8 head injured patients with an intracranial pressure (ICP) higher or lower than 25 mmHg (n = 4 for each group). NIRS values in the high ICP group (> 25 mmHg) were significantly lower than in the low ICP group (< 25 mmHg). In contrast, arterial pO2, pCO2, peripheral oxygen saturation and transcranial Doppler sonography (TCD) values were similar in both groups. To further investigate changes in rSO2 to changes in peripheral oxygen saturation and arterial pO2, patients of both groups underwent an artificial hyperoxygenation (50% O2) period of 3 minutes. Both groups revealed similar values in peripheral oxygen saturation, arterial pO2, and TCD velocities at the end of the hyperoxygenation period. However, rSO2 values in patients with an ICP > 25 mmHg were significant lower than in patients with an ICP < 25 mmHg after the hyperoxygenation period. In addition, patients with an ICP < 25 mmHg revealed a significant increase in rSO2 values at the end of the hyperoxygenation period, not detectable in patients with an ICP > 25 mmHg. Our results suggest that NIRS may be an additional diagnostic tool in the non-invasive evaluation of impaired cerebral microcirculation in patients with increased intracranial pressure.
