Comparative morphometry of myelinated nerve fibres in the normal and pathologically altered human sural and tibial nerve.

To assess neuropathological changes in human nerves, biopsies are usually performed on the sural nerve or other nerves supplying only a small area of skin. It is not yet clearly understood to what extent the changes found in this sensory nerve correspond to the changes found in other distal sensomotory nerves. To answer this question, we made a comparative morphometric analysis of the sural and tibial nerve. In 39 autopsy cases (aged 22 - 90 years) the sural and the tibial nerve were subject of image analysis. The histological picture in this study group was clearly influenced by neuropathological changes as well as age-related changes. For each morphometric parameter in the sural and tibial nerve, we evaluated Pearson's correlation. The highest coefficient of correlation (r) was seen in those parameters that represented the condition of the myelin sheath area: the density of nerve fibre area (sum of measured nerve, fibre areas/analyzed endoneural area) (r = 0.86) and the density of myelin sheath area (sum of measured myelin areas/analyzed endoneural area) (r = 0.86). Similar correlations were obtained for the mean of axon diameter (r = 0.82), the numerical density of nerve fibre count (nerve fibre count/analyzed endoneural area) (r = 0.77), the mean of nerve fibre diameter (r = 0.77) and the mean of myelin sheath thickness (r = 0.72). Our results revealed a good or very good statistical correlation of morphometric parameters between the two examined nerves. They support the assumption that the sural nerve sufficiently reflects the histological changes in other distal sensomotoric nerves. This is valid at least in systemic neuropathological diseases and age-dependent processes.

Penile and perianal pudendal nerve somatosensory evoked potentials in the diagnosis of erectile dysfunction.

Neurophysiologic examinations in differential diagnosis of erectile dysfunction comprise electromyogramme of the pelvic floor, pudendal nerve terminal motor latency (PNTML) and evaluation of pudendal somatosensory evoked potentials (SSEP). We focused our interest on comparing diagnostic importance of penile and perianal pudendal nerve SSEP. We examined 20 patients suffering from erectile dysfunction and 20 patients without any manifestation of impotence. The stimulus was administered using penile ring electrodes at the base of the penis (cathode) and distally on the penis shaft (anode), as well as a perianal surface electrode applied at 3 o'clock in lithotomy position and 5 cm laterally on the gluteal skin. The potentials were recorded with intradermal needle electrodes at C(z)-2 cm (different) and F(z) (indifferent). 500 stimuli were averaged for a single tracing. The stimulus strength was set at an average of 3-4 times the stimulus threshold. Cortical latency of P 40 ranged from 39.0 to 45.6 ms (penile) and from 33.6 to 43.2 ms (perianal) in the control group, in the patient group latencies ranged from 38.8 to 51.6 (penile) and 34.0 to 44.8 ms (perianal). In two patients no potential was recordable after perianal stimulation, one patient showed a marked prolongation of the penile response with a normal perianal latency. Penile and perianal latencies of P 40 were significantly prolonged in the patient group compared to the control group (P<0.05). The combination of penile and perianal pudendal SSEP may provide valuable additional information in differential diagnosis of erectile dysfunction, especially allowing to identify different sites of neurogenic lesions. In contrast to perianal pudendal SSEP, penile stimulation may help to discover pathologic changes in the distal course of the pudendal nerve, especially the dorsal nerve of the penis.

IgG-mediated cytotoxicity to myenteric plexus cultures in patients with paraneoplastic neurological syndromes.

Autoantibodies against neuronal and tumour proteins have been described in many paraneoplastic neurological syndromes (PNS), but it is not clear whether these antibodies are pathogenic or simply a useful diagnostic tool. We took seven sera that were positive on routine screening for antineuronal antibodies and the IgG fractions. As controls we used sera from health blood-donors, other neurological autoimmune diseases and patients with SCLC without PNS. We tested them on dissociated rat myenteric plexus cultures for cytotoxic effects. After incubation for 24 h, cytotoxicity was determined by a double fluorescence test (calcein green for living cells and ethidium homodimer-1 for dead cells). We found an increased cell death rate in cultures incubated with the PNS sera, compared with all controls (P< 0.05). Isolated IgG fractions were also cytotoxic whereas the IgG-free serum fraction did not show any significant increase in cytotoxicity. After incubation with PNS IgG, FACS analysis revealed an increased cytotoxicity rate only of the neurones, but not the glial cells. Our results indicate that in PNS a complement-independent, antibody-mediated cytotoxicity against neurones may contribute to the pathogenesis of these syndromes.

Intra- and interindividual reproducibility of heart rate variations in the tilt-table test.

Various methods are used for the routine diagnosis of autonomic regulation disorders. The evaluation of blood pressure and heart rate response during active orthostasis together with assessment of the 30/15-ratio (Ewing's ratio) was proven to be a valid method. One main disadvantage of these tests is their dependence on the active cooperation of the patient. In contrast, passive orthostasis using the tilt-table may also be carried out in bed-ridden patients. The test comprises a manual tilting manoeuvre of the patient lying on the tilt-table, with continuous assessment of heart rate and blood pressure. Until now, the main advantages of the tilt-table test were considered to be its better standardisation and good reproducibility, especially with regard to the diagnosis of vasovagal syncope. Several authors have postulated a specific pattern of initial heart rate response in healthy patients, showing characteristic changes in cases of underlying autonomic neuropathy. However, the diagnostic relevance of these tests is dependent on the reproducibility of the course of initial heart rate response. The objective of our study was to assess the intra- and interindividual reproducibility of initial heart rate response in the tilt-table test in healthy subjects. The tilt-table test was repeated 10 times in all 40 subjects under standardised conditions, and heart rate and blood pressure response were presented in a diagram. Reproducible courses of initial heart rate response were not seen, neither on intra- nor on interindividual comparison. After an initial rise, most subjects showed a rather horizontal course of heart rate, whereas others presented a heart rate response similar to that in the Ewing test, with an initial rise of heart rate around the 15th beat, followed by a decrease, and a maximum around the 30th beat. However, all subjects showed considerable variations in heart rate response within the 10 tilting manoeuvres. A reliable quotient comparable with the 30/15 ratio (Ewing's ratio) in active orthostasis was not seen. Based on these results, we conclude that the initial heart rate response in the tilt-table test is not suitable for routine diagnosis of autonomic regulation disorders, since it is not sufficiently reproducible in healthy individuals.

Antineural and antinuclear autoantibodies are of prognostic relevance in non-small cell lung cancer.

BACKGROUND: Autoantibodies against nervous system structures have been proven to be a prognostic factor in small cell lung cancer. However, little is known about humoral autoimmunity in non-small cell lung cancer (NSCLC) and its prognostic significance. METHODS: We examined antineural antibodies (AnAb) and antinuclear antibodies (ANA) in the sera of 61 patients with NSCLC (histologically: 29 adenocarcinoma, 32 squamous cell carcinoma). Twenty-one patients had stage I NSCLC, 11 stage II, and 29 patients stage III. Autoantibody detection was done by immunofluorescence test; Western blotting was used as a confirmation test. RESULTS: Of the NSCLC patients, 27.8% were antineural antibody positive, and 32.7% had ANA. No differences were found between the histological groups. AnAb-positive patients showed a better survival in all patients (p = 0.005). There was also a higher survival of ANA-positive patients, but this was only significant in stage III (p = 0.0025). Cox regression analysis showed that antineural and antinuclear antibodies are a stage-independent prognostic factor in NSCLC. CONCLUSIONS: Antineural and antinuclear autoantibodies are a stage-independent prognostic factor in patients with NSCLC and may represent an effective immune response to the tumor.

[Encephalomyelitis disseminata: clinical aspects, pathogenesis and current therapy concepts]. / Encephalomyelitis disseminata: Klinik, Pathogenese und aktuelle Therapiekonzepte.

Multiple sclerosis (MS) is considered as a T-cell mediated autoimmune disease. Caused by central nervous system demyelination and axonal damage varying clinical signs do occur either with relapsing-remitting or with chronic progressive course. Based on pathogenetic considerations immunomodulative and immunosuppressive therapeutical approaches are used to limit the disease progression. Clinical symptoms, diagnostic criteria, pathogenetical considerations, and consecutive therapeutical interventions are summarized.

[The oral vitamin E tolerance test--an attempt at standardization]. / Der orale Vitamin-E-Belastungstest--Versuch einer Standardisierung.

Chronic vitamin E deficiency causes various neurological symptoms such as cerebellar ataxia, hypoesthesia, areflexia, pigmentary retinopathy, nystagmus and muscle weakness. This is commonly caused by malabsorption of vitamin E, which is either a result of malabsorption of fat or occurs as an isolated vitamin E deficiency. The oral vitamin E tolerance test is suitable for the assessment of vitamin E reabsorption and elimination. However, standardised normal parameters have not yet been defined. We investigated 61 healthy individuals aged 18-70 years (mean age, 45.0 years). Each person involved in the trial received 100 IU of all-rac-alpha-tocopherol in 200 millilitres of whole milk. The vitamin E in the serum was then analysed 0, 3, 6, 9, 12, 24, 36, 48, 60, 72 hours after vitamin E was given, using high pressure liquid chromatography. The ratio of vitamin E to the sum of cholesterol and triglycerides was calculated. The 90% CI for the ratio of serum vitamin E to the sum of cholesterol plus triglycerides at the indicated time points was: t = 0 h: 2.0-6.3 micrograms/mg, t = 6 h: 4.2-15.3 micrograms/mg, t = 12 h: 3.0-13.0 micrograms/mg, t = 24 h: 3.8-14.4 micrograms/mg, t = 36 h: 2.9-10.5 micrograms/mg, t = 72 h: 2.1-8.7 micrograms/mg. The serum concentration of vitamin E correlated predominantly with the sum of cholesterol and triglycerides (r = 0.73). The ratio of these parameters is therefore most suitable for diagnosing vitamin E deficiency without relying on false normal serum vitamin E concentrations as a result of abnormally high serum lipid concentrations.

Shift in the IgG subclass distribution in patients with lung cancer.

Lung cancer patients have been reported to have generalized immune dysfunction of the cell-mediated immune response. In contrast, little is known about the humoral immune function in these patients. Therefore, we examined the IgG subclass distribution (IgG1-lgG4) in 67 lung cancer patients (23 adenocarcinoma, 29 squamous cell carcinoma, 15 small cell carcinoma), 13 patients with inflammatory lung diseases, seven patients with pulmonary metastasis and 23 healthy controls using a commercial available ELISA. We found a significant increase in the percentage of IgG1 in adenocarcinoma, compared with squamous cell and small cell lung carcinoma (P < 0.05). Small cell lung cancer patients showed an increase in IgG2, IgG3 and IgG4 compared with all other groups (P < 0.05, respectively). IgG1/lgG2, IgG1/lgG3 and IgG1/lgG4 ratios in adenocarcinoma were higher than in small cell lung cancer (P < 0.05). In the squamous cell carcinoma there was no difference in IgG subclass distribution compared to controls. Our study demonstrates that the different histological subtypes of lung carcinoma influence the IgG subclass distribution. Whether this phenomenon is the result of a direct influence on B-cell activity by the tumor needs further investigation.

Intravenous immunoglobulins in the therapy of paraneoplastic neurological disorders.

The treatment of paraneoplastic neurological syndromes (e.g., tumor therapy, immunosuppressive therapy, plasmapheresis) rarely leads to an improvement in the neurological symptoms. We treated four patients suffering from paraneoplastic neurological syndromes with intravenous immunoglobulins. All four had high titers of antineuronal antibodies in serum and CSF. Two of the patients, one suffering from paraneoplastic cerebellar degeneration and the other from paraneoplastic brain stem encephalitis and polyneuropathy, received intravenous immunoglobulin treatment within 3 weeks of the onset of neurological symptoms. Both patients showed clinical improvement within 2 weeks after the initiation of therapy. They also showed a decline in the intrathecal antibody synthesis of the antineuronal antibody. Two other patients, who had suffered from paraneoplastic neuropathy for 3 and 6 months showed no improvement with the intravenous immunoglobulin therapy. In these cases there was no effect on intrathecal antibody synthesis. When started early, intravenous immunoglobulins may be of therapeutical value in treating paraneoplastic neurological syndromes. Specific intrathecal antibody synthesis may be a better measure of clinical course that autoantibody serum titers.

Click evoked myogenic potentials in the differential diagnosis of acute vertigo.

OBJECTIVE: In response to loud clicks, a vestibular evoked potential can be recorded from sternocleidomastoid muscles, called "click evoked myogenic potential" (CEMP). This paper reports on the usefulness of CEMP in the differential diagnosis of acute vertigo of presumed vestibular origin. METHODS: CEMP was examined in 40 patients with acute vertigo of vestibular origin (26 with acute peripheral vestibulopathy, five with Ménière's disease, three with benign paroxysmal positioning vertigo (BPPV), six with psychogenic vertigo) and the results compared with standard caloric reaction (CR). For CEMPs, clicks were delivered unilaterally via a pair of headphones. EMG activity was collected by surface electrodes placed on the sternocleidomastoid belly and averaged. RESULTS: In 29 patients, CR was unilaterally abnormal, pointing to a peripheral vestibular lesion. Seventeen of them had a corresponding loss of CEMPs; the other 12 patients had a normal CEMP. The remaining 11 patients had normal results in both tests. In comparison with CR, CEMP showed a sensitivity of 59% and a specificity of 100% for peripheral vestibular disorders. CONCLUSION: CR is a test of the horizontal canal whereas CEMP is thought to be a sacculus test. Different results of CR and CEMP may be due to this difference between target organs stimulated and may be of prognostic value.

Orthostasis as a test for cerebral autoregulation in normal persons and patients with carotid artery disease.

Orthostasis reduces mean flow velocity (FVmean) in cerebral arteries. This might be used as an alternative provocation test for cerebral hemodynamics in patients with carotid artery disease (CAD). In 21 unilateral CAD patients and 21 controls, FVmean in both middle cerebral arteries (MCA) was measured by transcranial Doppler, together with blood pressure (BP) and heart rate (HR) during a tilt table test. Cerebrovascular reserve (CVR) was measured by an acetazolamide test. In all cases, FVmean dropped to a lower level (controls: 81.9 +/- 9.4% of baseline; patients: 84.3 +/- 7.9% symptomatic side, 85.6 +/- 9.0% contralateral). Impaired CVR patients showed a smaller (p < 0.01) decrease (90.6 +/- 3.3%) compared to contralateral (84.9 +/- 6.0%), to normal CVR patients (81.1 +/- 7.8%) and to controls. Heart rate increased in both groups (controls: +16.6 +/- 9.9%, patients +10.3 +/- 9.9%; p < 0.01); BP showed no change. Orthostasis induces a decrease of MCA FVmean as already previously described. This decrease is significantly smaller in patients with impaired CVR. Since BP does not change, some authors explain the lower MCA Fvmean during orthostasis as caused by sympathetic induced vasoconstriction of cerebral resistance vessels. The authors speculate that in impaired CVR-patients autoregulative protection against ischemia might limit vasoconstriction. In combination with standard tests for measurement of CVR, this test might be useful for evaluation of cerebral autoregulation.

SELEDO: a 5-year long-term trial on the effect of selegiline in early Parkinsonian patients treated with levodopa.

The SELEDO (from selegiline plus levodopa) study was carried out as a randomized, prospective, placebo-controlled, double- blind, multicenter long-term, 5-year trial to evaluate the possible advantages of combining selegiline and levodopa in the early treatment of Parkinson's disease. One-hundred-and-sixteen patients were randomized either to selegiline or placebo. Before starting the study medication, the levodopa dose was titrated to the individual requirements of each patient. The primary study end point (time when levodopa had to be increased by >50% of the titrated dose) was reached in 23 of 59 patients in the selegiline group and 26 of 48 patients in the placebo group. At the end of the 5 years' treatment period the rates derived from a life-table analysis were 50.4% in the selegiline group and 74.1% in the placebo group (P = 0.027, log-rank test). The median time to reach the primary end point was 4.9 years in the selegiline group and 2.6 years in the placebo group. In patients treated with selegiline, the mean levodopa dose changed only slightly over the 5 years of treatment compared to the initially titrated dose, but rose markedly in the placebo group, where the dose of levodopa had to be adjusted earlier than in the selegiline group. At the same time, the lower levodopa dosage in the selegiline group was accompanied by at least equal therapeutic efficacy (which is necessary for an unambiguous interpretation). Subgroup analyses showed greater benefit for selegiline treated) patients in the earlier stages. Long-term side effects appeared later in the selegiline group, although the difference was not significant. The early combination of selegiline and levodopa proved to be clearly superior to levodopa monotherapy.

Prevalence of antibodies to tick-borne encephalitis virus and Borrelia burgdorferi sensu lato in samples from patients with abnormalities in the cerebrospinal fluid.

Within the last few years, an increase in cases of tick-borne encephalitis (TBE) as well as an expansion of TBE-endemic regions have been noted in southern Germany. In 1994, a patient was diagnosed for the first time with TBE that had been acquired in Saarland. Up to this point, the Saarland had been considered TBE-free. In a retrospective study, we tested serum samples from 904 patients with abnormalities in the cerebrospinal fluid (CSF) for TBE antibodies. The IgG ELISA used (Immunozym-FSME-IgG, Immuno GmbH, Heidelberg, Germany) yielded 47 positive and 134 borderline sera. The percentage of positive sera showed a significant increase during the time period studied (1989-1994): One IgG-positive serum sample was also IgM-positive. Of the CSF samples, 2 were IgG-positive and 7 were borderline for IgG. In three patients, a positive intrathecal antibody index (IAI) was found, indicating an incrathecal antibody production. An analysis of the vaccination history of the patients showed that only 19% of the patients with a positive TBE IgG titre and only 5.9% of the borderline patients had been vaccinated against TBE. We compared 98 patients that tested positive or borderline for TBE IgG with 98 sex-and-age-matched patients that tested negative. The parameters studied included the patient's complaints upon discharge, the average duration of stationary treatment and 16 different neurological symptoms. We did not observe any significant differences between the two groups. We also tested the sera of 704 of the 904 patients for antibodies to Borrelia burgdorferi (Borrelia burgdorferi ELISA, Genzyme Virotech GmbH, Rüsselsheim, Germany). 155 (22.0%) of the sera were IgG-positive, 136 (19.3%) were borderline, 32 patients (4.6%) had a positive intrathecal antibody index (IAI). The fact that no patient with a clinically manifest case of TBE had acquired the disease in the Saarland indicates that the actual risk of acquiring an acute TBE in the Saarland is very low, despite the high percentage of samples that tested positive for IgG in the ELISA. The increase in the number of serum samples that tested positive for TBE IgG during the last years could be explained by an expansion of TBE regions into the Saarland, increasing vaccination of the population or more travel to endemic regions. The proportion of patients with IgG antibodies to Borrelia was 22%. Because only part of the patients suffered from an acute, clinically manifest borreliosis, and since the serum IgG titre had remained positive for many years after contact with the microorganisms, we suspected that a large percentage of the population would show signs of a clinically silent infection in their sera. 4.6% of the patients had a positive IAI quotient, a clear indication of neuroborreliosis.

Variability of velocity and duration of microembolic signals detected by bigated transcranial Doppler sonography in carotid endarterectomy.

OBJECTIVE: To differentiate between gaseous and particular microemboli in carotid surgery one clinical approach is the interpretation of the effective sample volume length (SVL). We investigated whether such a clinical interpretation is based on reproducible measurements. METHODS: Microembolic signals (MES) recorded during carotid endarterectomy by a bigated transcranial Doppler device were analyzed off-line. In the two sample volumes, the duration and the velocity of the MES were measured by two observers independently from each other twice within 2 weeks. The SVL of the MES were calculated by multiplying duration with velocity. RESULTS: In the anatomical proximal sample volume 215 MES were recorded of which 203 (94.5%) were also present in the distal. The SVL medians of the MES were 2.2-4.1 mm lower in the distal than in the proximal sample volume as a result of lower velocity and shorter duration of the MES in the distal sample volume. The median of the paired differences of the SVL was 0.2 mm (interquartile range: 0.0-1.2) in the proximal sample volume and 0.8 mm (0.2-1.8) in the distal sample volume for observer 1, and 0.6 mm (0.4-2.2) and 0.9 mm (0.5-1.6) for observer 2. The median of the paired differences of the SVL between the observers was 1.4 mm (1.2-2.9) in the proximal sample volume and 1.6 mm (1.3-3.0) in the distal. CONCLUSION: The intra- and interobserver agreement on calculating SVL is good. However, the depth of insonation influences some features of embolic signals.

[Value of antibody titers for diagnosis of neuroborreliosis]. / Wertigkeit von Antikörpertitern für die Diagnose einer Neuroborreliose.

Neuroborreliosis is a very frequent subtype of infection with Borrelia burgdorferi. Because of the widely spread inapparent infections finding of diagnosis by analysis of serum antibodies is very difficult. In the years 1990-1994 the serum of 6.775 patients of the Department of Neurology in Homburg, Germany was analysed with regard to Borrelia burgdorferi specific IgG antibodies. 24% showed a positive serum titer and 20% a borderline result. 73 patients showed a specific intrathecal IgG antibody synthesis. In contrast to patients with antibodies in serum these patients showed a significant cumulation during summer. The high percentage of positive serum titers and the season independence support the assumption of widely spread inapparent infections. If a patient shows neurological symptoms the finding of serum antibodies against Borrelia burgdorferi is not sufficient for the diagnosis of Neuroborreliosis. A specific intrathecal synthesis of antibodies, is the most reliable serological indicator for Neuroborreliosis. Intrathecal synthesis usually starts three to four weeks after the first clinical symptoms.

[Value of magnetic stimulation and F-wave determination in diagnosis of proximal demyelinating lesions. Follow-up of acute Guillain-Barré polyradiculitis]. / Wertigkeit der Magnetstimulation und der F-Wellenbestimmung in der Diagnostik proximaler demyelinisierender Läsionen. Verlaufsbeobachtungeiner akuten Polyradikulitis Guillain-Barré (GBS).

A 47-year-old woman developed acute Guillain-Barré-syndrome (GBS) within one day, presenting tetraparesis (muscle strength 1/5 for the upper and 2/5 for the lower extremities) and respiratory failure. On day 5 a cardiac pacemaker was necessary due to severe bradycardia. Electrophysiological studies were performed on days 2, 3, 5, 6, 8, 12, 15, 30 and 40. Our initial findings revealed normal motor conduction velocities and normal spinal motor evoked potentials. However, neither F-waves nor cortical motor evoked potentials could be registered from the upper or lower extremities. The motor conduction of the median nerve remained normal until day 6. The compound motor action potential declined thereafter and disappeared by day 12, indicating axonal degeneration. No axonal degeneration occurred in the lower extremities. The cervical or lumbar magnetic stimulation excites nerve roots at the level of the foramen intervertebrale. Thus, our findings suggest a conduction block between the foramen intervertebrale and the point where the nerve roots enter the spinal cord.

Femoral injection of echo contrast medium may increase the sensitivity of testing for a patent foramen ovale.

OBJECTIVE: The diagnosis of a patent foramen ovale (PFO) as a cause of stroke is of increasing interest especially in young (<45 years) patients. METHODS: We studied potential right-to-left shunting using transesophageal echocardiography (TEE) and bilateral transcranial Doppler sonography (TCD) of the middle cerebral artery (MCA) simultaneously in 44 patients. All patients were younger than age 45 years and suffered from an acute ischemic stroke or transient ischemic attack. Other possible etiologies were excluded. Echo contrast medium was injected in an alternating mode via antecubital or femoral veins. Tests were performed with and without the Valsalva maneuver. The criteria for a PFO were that the contrast pass from the right to the left atrium (TEE) and early detection (<10 seconds) of more than 10 micro air bubbles in at least one MCA by TCD. RESULTS: A PFO was diagnosed in 22 patients (50%). The detection rate with TEE/TCD was 11.4%/4.5% via antecubital injection, 18%/13.6% via antecubital injection plus the Valsalva maneuver, 38.6%/36% via femoral injection alone, and 50%/50% via femoral injection plus the Valsalva maneuver. The difference between femoral and antecubital injections was significant with and without the Valsalva maneuver (p < 0.01, chi2 test). There were no differences between TEE and TCD after femoral injection with the Valsalva maneuver. The brain transit time was 4.6 +/- 2.1 seconds for femoral injection and 6.3 +/- 4.1 seconds for antecubital injection. CONCLUSIONS: The sensitivity in detecting a PFO was markedly increased by femoral injection. This may be caused by different inflow patterns to the right atrium: inferior vena caval flow is directed to the right atrial septum, whereas superior vena caval flow is directed to the tricuspid valve. Thus, femoral injection may help to improve the detection of PFO and may explain the differences between TEE and TCD findings in previous studies.

Alteration of cerebral blood flow in patients with bacterial and viral meningoencephalitis.

PURPOSE: Our purpose was to investigate cerebral blood flow disturbances in patients with bacterial and viral meningoencephalitis. METHODS: Forty-two patients with acute bacterial and viral meningoencephalitis and 14 control subjects were studied using 99mTc-hexamethylpropyleneamine oxime (HMPAO) single-photon emission computed tomography (SPECT). SPECT images were evaluated semiquantitatively. The results were compared with clinical severity of the meningoencephalitis assessed at the time of the SPECT study with the Hunt and Hess scale, with separately recorded focal clinical signs, and with the Glasgow outcome scale (GOS) after 3 weeks. RESULTS: Count density values were significantly reduced in patients with bacterial meningoencephalitis as compared with the control subjects. Inhomogeneous tracer accumulation assessed by asymmetry indexes was significantly greater in patients than in the control group. With increasing Hunt and Hess scores, the count density values decreased and the asymmetry indexes increased. Patients with a poor outcome (GOS 1 to 3) had significantly higher asymmetry indexes and lower CDV values than did patients with a good outcome. CONCLUSION: Global and focal alterations of cerebral perfusion are frequent in bacterial and viral meningoencephalitis and correlate with acute clinical state.

Influence of the angiographic internal carotid artery stenosis assessment method on indicating carotid surgery.

BACKGROUND: To estimate the influence of different kinds of angiographic internal carotid artery (ICA) stenosis assessment methods on clinical decision making on carotid surgery. METHOD: One hundred angiographically proven ICA lesions in 65 patients (54 men, 11 women, mean age +/- SD, 64 +/- 8 years) were evaluated by simultaneous biplane angiography. The angiograms were analyzed using three kinds of linear diameter reduction methods [North American (NASCET), and European (ECST) carotid surgery trial method, common carotid artery method (CC)], and five area reduction methods reflecting more accurately the anatomical degree of stenosis [squared NASCET, ECST and CC (N2, E2, CC2), combined stenosis estimation of two projections (NASCET-bi, ECST-bi)]. All lesions were additionally evaluated by continuous wave (cw-)Doppler ultrasound prior to angiography. Between method agreement on classifying the lesions into stenosis < 70% and into stenosis > or = 70% was calculated by means of kappa statistic. RESULTS: The degree of stenosis (median and inter-quartile range) ranged between 65% (38-82) by means of NASCET and 91% (87-93) by means of CC2. Thirty-seven ICA stenoses would have been operated on using NASCET, but 82 using CC2. Between method agreement on assessing high grade ICA stenosis ranged from poor (kappa value 0.17 for the pair NASCET/CC2) to excellent (kappa value 0.92 for the pair N2/NASCET-bi). Cw-Doppler ultrasound showed a good agreement (kappa value 0.72-0.80) with all angiographic methods using an area reduction formula apart from CC2. The agreement was moderate between cw-Doppler and NASCET and ECST, respectively. CONCLUSION: The clinical decision to operate on an ICA stenosis will strongly be influenced by the angiographic method used. Because reliable clinical data exist only for the NASCET and ECST method these two angiographic stenosis assessment method should be used for clinical decision making.