This study is the first report on human intracranial temperature in conscious patients during and after an upper respiratory bypass. Temperatures were measured in four subjects subdurally between the frontal lobes and cribriform plate (T(cr)) and on the vault of the skull (T(sd)). Further measurements were taken in the esophagus (T(es)) and on the tympanic membrane. Reinstitution of airflow in the upper respiratory tract under conditions of mild hyperthermia gave a rapid drop in T(cr) of 0.4-0.8 degrees C. In three patients the intracranial temperature at the basal aspect of the frontal lobes fell below T(es). Thus local selective cooling of the brain surface below that of the trunk temperature was shown to occur. Intensive breathing by the patients after extubation for a 3-min period produced a cooling at the site of T(cr) measurement at a rate of up to 0.1 degrees C/min, and this response could be evoked on demand. The results support the view that cooling of the upper airway can directly influence human brain temperature.

Knowledge about human brain temperature is still very limited, despite evidence demonstrating the critical influence of mild increases in temperature on the ischaemic brain. It has been suggested that in passive and exercise hyperthermia the brain may be protected against thermal damage by a mechanism of selective brain cooling (SBC). It is said to bring about suppression of the temperature of the brain, rendering it significantly lower than trunk and arterial blood temperature. Yet very little is known about the possible role of this mechanism in fever, a condition fundamentally different from "physiological" hyperthermia, especially when it occurs in brain-damaged patients. In our investigation we retrospectively analysed the results of direct recordings of cerebral temperature within the subdural space (Tsd) and within the brain parenchyma (Tbr-16 cases) in 63 unanaesthetized patients following neurosurgical procedures, including 23 with fever > 38 degrees C. The difference between trunk temperature, measured in the rectum (Tre) or in the oesophagus (Tes), and the intracranial temperature, were calculated in all subjects. A statistically significant reduction of these differences, in step with increasing fever, would be compatible with demonstrating a process of selective brain cooling. The offsets Tre-Tsd, Tre-Tbr, and Tes-Tsd were plotted against Tre over a wide range of body temperature and near zero correlation was found. This finding suggests that brain temperature in fever was not selectively suppressed by any specific thermolytic mechanism and that dissipation of the main bulk of cerebral metabolic heat both in normothermia and in fever depends on heat uptake by arterial blood. The results suggest that the brain in fever can be seriously jeopardized by heat stress and no specific cooling mechanism exists, to reduce it below body temperature in feverish neurosurgical patients. Tbr and/or Tsd remained the highest body temperature in 14 out of the 23 patients during fever.

The image-guided neuro-navigation system facilitated endoscopic localisation and biopsy of intraorbital tumours and contributed to the reduction of surgical trauma during the procedure. The technique was particularly useful in small, medially located, retrobulbar tumours and in unclear situations when the structure of the lesion resembled surrounding intraorbital tissue.

This study provides normal reference values for the V(ICA)/V(CCA) ratios for PSV and shows that the ratio varies with age and sex. The upper reference limit for the ratio can serve as an aid in the more specific identification of patients with minor or mild ICA narrowing.

SummaryBackgroundIsolated sphenoid sinus pathologies are relatively rare. In the majority of cases, symptoms do not arise in the early stages of the disease or are non-specific, therefore making diagnosis difficult. The aim of this study was to investigate the diagnostic process and the reasons for development of complications in patients with isolated sphenoid sinus pathology.Material/MethodsThe clinical data and observation charts of 32 patients were investigated to determine how long the main symptoms of sphenoid pathology had been present before the patients were referred for medical treatment, and the time that elapsed from the first ambulatory medical assessment to the initial diagnosis.ResultsComplaints and symptoms of sphenoid sinus pathology had been present for 10.2 months before the diagnosis was established. Although the duration of complaints in “ORL” (diagnosed by otorhinolaryngologist) and “non-ORL” (diagnosed by other specialists) group of patients was similar (10.8 and 9.5 months on average, respectively), unexpectedly, in the “non-ORL” group of patients, the time necessary for making the initial diagnosis was actually shorter than in the “ORL” group (1.8 vs 4.1 months). At the time of hospital admission, endoscopic examination revealed no abnormalities in 31.2% of patients. In 28.1% of patients the pathological process in the sphenoid sinus was diagnosed only after the onset of complications.ConclusionsThe occult character of the disease and the lack of severe and specific symptoms, rather than the delay in getting extensive diagnostic tests, are responsible for the delayed diagnosis and treatment.

The results suggest that the direct effect of smoking on cerebral circulation includes peripheral vasodilatation with possible constriction of the main trunk of the basal cerebral arteries.

OBJECT Distal coil or stent migration is a rare, but potentially morbid complication of intracranial aneurysm embolization. At present, there is no established standard of surgical evacuation of displaced material—in particular, there is no consensus on the optimum time for such intervention. The authors report their positive experiences with an ultra-early surgical evacuation of 2 migrated coils and a flow-diverter stent. METHODS Uncontrolled coil or stent migration occurred in 3 (0.75%) of approximately 400 patients treated between 1999 and 2012 in the authors' institution. In all 3 cases, the materials moved from their intended position to the middle cerebral artery (MCA). Surgical evacuation was started immediately (within half an hour) after a futile attempt of removing them via intraarterial route, under the same anesthesia and with no active reversal of heparinization. RESULTS No excessive bleeding was observed. Displaced coils were extracted through an incision of a branch of MCA—the anterior temporal artery, the stent was removed through a direct incision of MCA. Recombinant tissue plasminogen activator (rtPA) was injected to the stem of the internal carotid artery toward the end of the procedure, with no discernible adverse effects. Two patients were discharged with no deficit (Glasgow Outcome Scale [GOS] Score 5); the other patient was conscious with mild hemiparesis (GOS Score 4) at discharge. CONCLUSIONS The experiences of these 3 cases suggest that immediate removal of a migrated stent/coil is feasible and may be effective. Indirect access to the MCA through its branch helps to shorten the time of temporary clipping of the artery to a minimum. Maintaining active heparinization and direct intraarterial injection of rtPA are helpful in promoting blood flow in the MCA.

The purpose of the study was to identify extracranial locations in which temperature changes in humans reflect those of intracranial temperature in a reliable and repeatable way. This was achieved by subjecting 14 non-anaesthetized patients after neurosurgery to face fanning while intracranial and extracranial temperatures were continuously measured. In all patients the cranium was closed and the group included both febrile and non-febrile as well as hyperthermic and normothermic patients. The patients' faces were fanned for 20-30 min, with a small fan at an air speed of 3.25 m s(-1). This gave intracranial temperature changes measured in the subdural space ( T(sd)) that were highly and significantly correlated ( r=0.91, P<0.05, n=14) with changes in tympanic temperatures ( T(ty)). A low, statistically insignificant correlation ( r=0.40, P>0.05, n=12) was found between T(sd) and oesophageal temperatures. In conclusion, intracranial temperature changes, induced by face fanning, were reliably reflected by the changes in T(ty).