[Novel approaches to control the rise in pertussis cases]. / Nové prístupy v kontrole vzestupu poctu onemocnení pertusí.

UNLABELLED: Pertussis is a respiratory disease caused by the Gram-negative encapsulated bacterium Bordetella pertussis. Despite the high vaccination coverage rate and addition of new booster doses to the immunisation scheme (in response to the epidemiological situation), pertussis is on the rise not only in the Czech Republic but also in many other countries. The age groups at highest risk are infants and, to a lower extent, newborns who can get infected before receiving the first dose of vaccine and develop a severe course of the disease, often requiring admission to hospital. The most common source of infection are adults or adolescents from the childs close environment who experience a mild course of the disease because of the previous vaccination. The immune response induced by the currently available acellular vaccines does not last. It can be reasonably assumed that pertussis has been underreported. Multiple studies have shown mutations in the causative bacterium that confer higher pathogenicity to it, either as a result of enhanced production of pertussis toxin or loss of some antigens. Possible strategies to control these negative trends are to develop novel more effective vaccines using new adjuvants or to use whole-cell vaccines. Maternal vaccination in pregnancy trimester 3 also turned out to be effective. KEY WORDS: pertussis - vaccination - epidemiology - diagnosis - newborns.

[Ovaria borderline tumor - fertility-sparing surgery; case report]. / Fertilitu zachovávající lécba borderline tumoru ovaria - kazuistika.

The borderline tumors are known as low malignant potential tumors. Usually younger women suffer for them, than by the invasive ovarian carcinoma. They often which to be pregnant. The fertility-sparing surgery is posile but contain higher risk of the new disease on contralateral ovary.

[Percutaneous interspinous dynamic stabilization (in-space) in patients with degenerative disease of the lumbosacral spine - a prospective study]. / Perkutánní interspinózní dynamická stabilizace (In-Space) u nemocných s degenerativním onemocnením lumbosakrální pátere - prospektivní studie.

INTRODUCTION: Interspinous spacers are supposed to reduce the segmental extension with a decrease in the expansion of yellow ligaments into the spinal canal, thus avoiding the dynamic narrowing of the spinal canal and compression of nerve roots. The aim of this study was to evaluate clinical outcomes and post-operative complications during one year in patients mostly having suffered from spinal stenosis and treated by In-Space interspinous spacer (Synthes, USA). MATERIAL AND METHODS: A total of 25 patients aged between 25 and 73 (average age 52.6) years, including 18 males and 7 females, with degenerative disease of the lumbosacral spine were indicated for surgery and prospectively followed up. The patients were operated on under general anaesthesia in the prone position, using a minimally invasive lateral percutaneous approach, under fluoroscopic control. The ODI and VAS values as well as X- rays (Range Of Motion and Sagittal angle of the operated segment) 6 and 12 months after the surgery were compared to each other and to those before surgery. The results were statistically analyzed. RESULTS: The average ODI of the group was 47.2% before surgery and 17.48% 6 months (22.76% 12 months) after surgery, showing a statistically significant improvement by 63% (52% after 12 months). The average VAS of the group was 6.64 points before surgery and 2.96 points 6 months (2.8 points 12 months) after surgery, which showed a statistically significant improvement by 55.4% after 6 months (57.8% after 12 months) when compared to preoperative status. After surgery the lordotic sagittal angle remained in all cases; one year after surgery the angle increased due to the slight sinking of some implants. The extent of segmental motion was minimally changed (6.1° 6 months and 7.24° 12 months after surgery). No serious complications occurred. The effect of interspinous implants proved insufficient in two cases (one year and two years after surgery) and conversion to arthrodesis or decompression was performed. CONCLUSIONS: 1. Percutaneous, minimally invasive insertion of an In-Space interspinous spacer is an effective and safe method of dynamic stabilization not accompanied by any serious complications. 2. ODI improved by 63% 6 months after surgery with a decrease in this effect 12 months after surgery. VAS for axial and radicular pain, as reported by patients, improved on average by 55.4% 6 months and by 57.8% 12 months after surgery. 3. In all cases, the lordotic sagittal angle remained after surgery and the extent of segmental motion from flexion to extension was minimally changed.

Fishnet metamaterials--rules for refraction and limits of homogenization.

The perfectly conducting stacked fishnet metamaterial is studied in this paper. The analysis is based on a combination of the mode matching method together with the generalized eigenvalue problem, and takes into account wave propagation along all three Cartesian axes. The analysis has been developed for a fishnet of square lateral periodicity and for two particular polarizations, namely TE and TM, corresponding to the two most common excitations. The 1D and 2D dispersion characteristics are calculated for both polarizations, showing that the TM waves undergo negative refraction in a narrow frequency band just below Wood's anomaly, whereas TE polarized waves exhibit ordinary positive refraction. Finally, possible homogenization of the fishnet metamaterial is considered, showing that only for small angles of incidence and in the immediate vicinity of Wood's anomaly can the fishnet be seen as homogenizable uniaxial medium.

[The DIAM spinal stabilisation system to treat degenerative disease of the lumbosacral spine]. / Implantace interspinózní rozperky DIAM u pacientu s degenerativním onemocnením lumbosakrální pátere.

PURPOSE OF THE STUDY: Each dynamic stabilisation should preserve motion at the operated segment as well as reduce a load on the disc and intervertebral joints. One of the methods to achieve this is the implantation of interspinous spacers between lumbar spinous processes. In this study, the patients treated with the DIAM interspinous spacer (Medtronic, USA) were prospective- ly followed up with the aim to evaluate clinical outcomes and post-operative complications. MATERIAL: Patients with a degenerative disease of the lumbosacral spine were indicated for the operation. They suffered from axial pain with signs of nerve root involvement due to disc hernia, foraminal stenosis or disc herniation recurrence A total of 68 patients aged 23 to 75 (average age, 50.01) years, including 39 men (average age, 50.44) and 29 women (average age, 49.45), were followed up for 1 to 3 years and evaluated. METHODS: All patients underwent a standard pre-operative clinical and neurological examination. Each patient assessed pain intensity using a Visual Analogue Scale (VAS) and, with an Oswestry Disability Index (ODI) questionnaire, evaluated their functional state. In the case of disc hernia or disc herniation recurrence, a sequester was removed; for foraminal stenosis, foraminotomy and partial medial facetectomy was performed. After this decompression of nerve structures, a spacer was implanted. Follow-up included clinical and neurological examination at 6 weeks, 6 months and 1 - 3 years post-operative- ly. At 6 months and between 1 and 3 years after surgery, pain intensity and functional outcome using VAS and ODI assessments were measured by the patients, and antero-posterior and lateral skiagrams of the lumbosacral spine were made. The X-ray examination was made to reveal a potential implant dislocation. The VAS and ODI values at 1-3 post-operative years were compared with those before surgery and the results were statistically analysed. The surgeon evaluated the outcomes at 1-3 years of follow-up according to the Odom criteria. RESULTS: The average ODI of the group was 60.44 % before and 21.85 % after surgery, which showed an improvement by 63.85%. The average VAS was 7.18 points before and 2.10 points after surgery, showing an improvement by 70.75 %. A comparison of the pre- and post-operative results showed, in the average ODI differences of 38.24 % and 39.44 % in women and men, respectively; and in the average VAS value, 5.00 in women and 5.19 in men. The results evaluated according to indication for surgery were as follows: in patients with disc hernia, the difference in ODI was 39.62 % on average, and in VAS it was 5.42 points on average. In patients with disc herniation recurrence, the differences between pre- and post-operative average values were 41.50 % for ODI and 5.00 points for VAS. In patients treated for foraminal stenosis, these differences were 39.79 % for ODI and 5.18 points for VAS. The results for the level treated showed that at L5/S1 the average difference for ODI was 46.75 % and 4.50 points for VAS ; at L4/5 it was 35.52 % for ODI and 5.12 for VAS; at L3/4 it was 48.00 % for ODI and 5.78 for VAS; and at L2/3 it was 39.00 % for ODI and 4.50 for VAS.The results related to the method of nerve root decompression included the average differences of 40.00 % in ODI and 5.17 in VAS for removal of a disc sequester; and average differences of 32.89 % in ODI and 4.78 in VAS for foraminotomy and partial medial facetectomy. The results evaluated for the duration of pre-operative complaints were as follows: surgery by 3 months, average ODI, 44, 53 % and average VAS, 5.25; surgery between 3 and 6 months, average ODI, 37.65 % and average VAS, 4.71; and surgery after 6 months, average ODI, 35.60 % and average VAS, 5.28. The Odom criteria showed results as excellent in 41 %, good in 51.5 % and fair in 7.5 % of the patients. No poor result was recorded. There were no early complications such as haematoma, wound seroma or deep subfascial infection, and no implant dis- location. One patient had to undergo repeat surgery for subcutaneous infection without affecting the implant. Until the end of the study, no signs of herniation recurrence at the segment stabilised with a Diam interspinous spacer had been found. DISCUSSION: The fact that none of the patients in this study required revision surgery or had a recurrence of disc herniation provides evidence for the effectiveness of the DIAM interspinous spacer.This also suggests that the implant protects the whole operated spinal segment, i.e., both intervertebral joints and discs, from being overloaded. Lesser mechanical stress applied to intervertebral facets may slow down degenerative processes and reduce their signs. CONCLUSIONS: The implantation of a DIAM interspinous spacer is a less invasive and safe method of dynamic stabilisation of the spi- ne without intra- or post-operative complications that is well tolerated by the patient. At 3-year follow-up the patients reported improvement in their functional state, as measured with an ODI, by 64 % on the average. Their axial and nerve root pain was reduced by 71 % on the average. All patients showed improved clinical conditions and the outcomes were evaluated as excellent in 41 %, good in 51 % and fair in 7.5 % of the patients. The results of implantation were not significantly related to age, gender, operative indications, operated lumbosacral level, method of nerve root decompression or duration of pre-operative problems. No patient treated by the DIAM spacer had any recurrence of disc herniation.

Histological analysis of retraction pocket pars tensa of tympanic membrane in children.

AIMS: Histological and histochemical analysis of retraction pocket of pars tensa of tympanic membrane in children. Identification of morphological abnormalities in comparison with a healthy tympanic membrane as it is described in standard textbook. Identification of signs typical for cholesteatoma and support for a retraction theory of cholesteatoma formation. STUDY DESIGN: A prospective study analysing 31 samples of retraction pockets taken during surgery. DEPARTMENTS: University Hospital, Children's Medical Centre METHODS: Samples of retraction pockets were processed by a standard process for light microscopy, stained by haematoxylin-eosin. Van Gieson's stain was used for differential staining of collagen, Verhoeff's stain for elastic fibre tissues, Alcian blue for acidic polysaccharides and PAS (Periodic Acid Schiff) method for basement membrane polysaccharides. RESULTS: The following findings were observed in the samples of retraction pockets: hyperkeratosis (100%), hypervascularisations (100%), subepithelial fragmented elastic fibres (96%), myxoid changes (87%), subepithelial inflammatory infiltration (84%), rete pegs (71%), papilomatosis (71%), intraepithelial inflammatory cellularizations, (48%), intraepithelial spongiosis (16%) and parakeratosis (3%). No basement membrane continuity interruptions were observed. Thickness of retraction pocket, thickness of epidermis, occurrence of rete pegs and frequency of fragmented elastic fibres was higher in a Grade III stage RP than Grade II stage RP (according to Charachon). CONCLUSION: Morphological abnormalities in the structure of retraction pockets in comparison with a healthy tympanic membrane were described. The changes are typical for a structure of cholesteatoma (these changes are common in matrix and perimatrix), supporting retraction theory of its origin. Our observations show that it is inflammation that probably plays a key role in the pathogenesis of retraction pocket. The frequency of some of the changes increases with the stage of retraction pocket (II-III according to Charachon). Basement membrane continuity interruptions are not typical for retraction pockets.

A comparative study of frequency domain and time domain analysis of signal-averaged electrocardiograms in patients with ventricular tachycardia.

Although both time domain and frequency domain analysis of signal-averaged electrocardiograms (ECGs) may distinguish patients with and without sustained ventricular tachycardia, it remains unclear which method is superior. Both methods were assessed in 55 subjects comprising 26 patients with sustained ventricular tachycardia (Group I), 18 control patients with organic heart disease but without sustained ventricular tachycardia (Group II) and 11 normal volunteers (Group III). Time domain analysis was performed with high pass filtering of 25, 40 and 80 Hz and low pass filtering of 250 Hz. Frequency domain analysis was performed on the terminal 40 ms of the QRS complex, either alone or with 216 or 150 ms of the ST segment. Absolute summed energies of discrete frequency bands and band energy ratios were calculated. The effectiveness of discrimination between Groups I and II was evaluated in terms of group means, sensitivity, specificity and an information content index based on receiver operating characteristic curve analysis. Group I showed a uniform decrease in amplitude across all frequencies derived from the terminal 40 ms of the QRS complex (p less than 0.005). This was abolished by the inclusion of ST segment data in frequency domain analysis. No frequency band was unique for Group I. At a specificity of 78%, the best time domain sensitivity was 85%, and the best frequency domain sensitivity was 77%. The best time domain information content index was 0.156, the best index for frequency domain analysis was 0.077 using absolute band areas. It is concluded that patients with sustained ventricular tachycardia have decreased energy content across all frequencies in the terminal 40 ms of the QRS complex. Frequency domain analysis was not an improvement over time domain analysis in differentiating patients with ventricular tachycardia from those without.

The prognostic significance of quantitative signal-averaged variables relative to clinical variables, site of myocardial infarction, ejection fraction and ventricular premature beats: a prospective study.

A prospective study was undertaken of the prognostic significance of quantitative signal-averaged electrocardiographic (ECG) variables relative to clinical variables, site of myocardial infarction, left ventricular ejection fraction and characteristics of ventricular premature beats in 115 patients (mean age 62 +/- 12 years) studied 10 +/- 6 days after myocardial infarction. Signal-averaged variables included the root mean square voltage of the terminal 40 ms, the duration of the filtered signal-averaged QRS complex and low amplitude signals less than 40 microV determined at 25 and 40 Hz high pass filtering in all patients. Of the 115 patients, 51 (44%) had an abnormal signal-averaged ECG (one or more abnormal signal-averaged variables), 51 (44%) at 25 Hz and 48 (42%) at 40 Hz high pass filtering. A higher proportion of patients with an inferior wall infarction had an abnormal signal-averaged ECG as compared with patients with anterior wall infarction (58% versus 31%). Over a 14 +/- 8 month follow-up period 16 patients (14%) had an arrhythmic event. An abnormal signal-averaged ECG at 40 Hz high pass filtering had a higher sensitivity (81% versus 75%) and specificity (65% versus 61%) than at 25 Hz high pass filtering. The predictive value of the signal-averaged ECG was superior to that of the ejection fraction (40% versus 20%) in anterior wall myocardial infarction, whereas in patients with inferior wall infarction, the predictive values of the two tests were equivalent. The prognostic power of 27 clinical and noninvasive variables was determined with the Cox proportional hazards regression model.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical and electrophysiologic determinants, treatment and survival of patients with sustained malignant ventricular tachyarrhythmias occurring late after myocardial infarction.

To assess the clinical and electrophysiologic determinants, treatment and survival of patients with sustained malignant ventricular tachyarrhythmias late after myocardial infarction, a total of 108 patients (mean age 61 +/- 10 years) were studied. Thirty-two patients (Group I) had sustained ventricular tachyarrhythmias 8 to 60 days (mean 13 +/- 9) after acute myocardial infarction. The remaining 76 patients (Group II), who served as a control group, had no sustained ventricular tachyarrhythmias less than or equal to 60 days after infarction. The most significant independent determinants of sustained ventricular tachyarrhythmias late after infarction were the presence of late potentials (chi square = 16.07, p = 0.0001), defined as an abnormal signal-averaged QRS complex in association with an abnormal root-mean-square voltage in the terminal 40 ms of the QRS complex, and an abnormal ejection fraction of less than 40% (chi square = 10.09, p = 0.001). Sustained ventricular tachycardia was induced in 27 (96%) of 28 Group I patients. Among the 32 patients in Group I, antitachycardia therapy included antiarrhythmic drug therapy as the sole preventive measure in 14 (44%); map-guided surgery or coronary artery bypass surgery, or both, in 14 (44%) and the automatic cardioverter-defibrillator in 4 (12%). The arrhythmias were rendered noninducible in 83% of patients after map-guided surgery and in 41% after drug therapy. During a follow-up period of 20 +/- 14 months, five Group I patients (15%) had an arrhythmic event and four (9.3%) had a cardiac-related death. All five patients who had an arrhythmic event were receiving antiarrhythmic drug therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial kinetics and left ventricular diastolic filling in the healthy elderly.

A delay of left ventricular isovolumic relaxation and decrease in myocardial compliance may result in a decline of measured early filling rates in elderly subjects. Previous studies of diastolic function, however, have not excluded coronary artery disease or addressed the contribution of atrial contraction to diastole. The present study evaluated radionuclide-derived diastolic variables in 13 healthy elderly volunteers aged 75 +/- 6 years without symptoms or risk factors for coronary disease who had normal findings on the stress electrocardiogram, stress gated blood pool imaging and two-dimensional echocardiogram. Results were compared with those of a group of 10 healthy young volunteers aged 26 +/- 5 years. High count, 32 frame, double-buffered gated blood pool acquisitions were obtained at rest in the left anterior oblique view with an RR interval variation less than 5%. Left ventricular time-activity curves were analyzed and flow-volume loops for each group were constructed. In the healthy elderly: peak early diastolic filling rate is decreased, time of peak early filling and time to first third of diastolic filling are delayed, and peak late left ventricular filling rate and percent of atrial filling volume are augmented, suggesting an adaptive response of the atria to diminished left ventricular compliance.

Quantification of cardiac conduction abnormalities using segmental vector Fourier analysis of radionuclide gated blood pool scans.

Timing abnormalities of myocardial contractility may occur as inter- or intraventricular asynchrony. Gated blood pool scintigraphy was performed on 21 patients with a normal ejection fraction and the following electrocardiograms: six normal, six with left bundle branch block, four with right bundle branch block and five with right ventricular pacemaker rhythm. A phase and amplitude of the first harmonic of the Fourier transform was obtained for each pixel, and left and right ventricles were trisected. A mean vector phase for each region was obtained by vector summation. Regional and global values were analyzed within each group and compared with normal values. The phase differences between the entire left and right ventricles (mean +/- standard deviation) were: 9 +/- 3 in the normal patients, 38 +/- 8 (p less than 0.01) in patients with left bundle branch block, -6 +/- 7 (p less than 0.05) in patients with right bundle branch block and 15 +/- 9 (difference not significant) in patients with pacemaker rhythm. The phase differences between left ventricular posterolateral and septal regions were -4 +/- 2 in the normal patients, 10 +/- 5 (p less than 0.01) in patients with left bundle branch block, -7 +/- 10 (p less than 0.05) in patients with right bundle branch block and 10 +/- 5 (p less than 0.01) in patients with pacemaker rhythm. Within the right ventricle, phase differences between the apical and septal segments were 14 +/- 9 in the normal patients, 14 +/- 10 (NS) in patients with left bundle branch block, -2 +/- 3 (p less than 0.01) in patients with right bundle branch block and -22 +/- 18 (p less than 0.01) in patients with pacemaker rhythm. Interventricular phase differences were greatest in patients with left bundle branch block and absent or reversed in right bundle branch block.(ABSTRACT TRUNCATED AT 250 WORDS)

Dorsal striatal size, shape, and metabolic rate in never-medicated and previously medicated schizophrenics performing a verbal learning task.

BACKGROUND: Magnetic resonance imaging and positron emission tomography were used to study the size and metabolic rate of the caudate and the putamen in 18 patients with schizophrenia (n=16) or schizo-affective disorder (n=2) and 24 age- and sex-matched control subjects. METHODS: The patients were either never medicated (n=7) or drug free (n=11) for a median of 3 weeks. During uptake of fludeoxyglucose F 18, all patients performed a serial verbal learning test. Positron emission tomographic and magnetic resonance imaging scans were coregistered, and the caudate and the putamen were traced on the magnetic resonance image. RESULTS: The striatum had a significantly lower relative metabolic rate in schizophrenics than in controls. Never-medicated patients had lower metabolic rates in the right putamen (ventral part of the dorsal striatum) than previously medicated patients. The caudate was significantly smaller in never-medicated patients than in controls and largest in previously medicated patients. Patients with higher relative metabolic rates in the putamen scored higher on the Abnormal Involuntary Movements Scale. CONCLUSIONS: The findings are consistent with reports of striatal enlargement in previously medicated patients and size increases after neuroleptic treatment. Never-medicated patients, in contrast, had ventral striatal structures that were smaller and less active than those observed in controls and previously medicated patients.

[The management of uterine fibroids: Czech and Slovak Gynecologic Endoscopy Working Group (CSGE) clinical practice guidelines]. / Management delozních myomu: CSGE doporucení k provádení spráivné klinické praxe.

OBJECTIVE: The objective of this paper is to give a guideline to the management of uterine fibroids. DESIGN: Review. SETTING: Czech Society Gynecological Endoscopic Working Group. MATERIAL AND METHOD: The bibliographic data from Medline were reviewed from 2003-2004 using the key words: fibroid--leiomyoma--uterine artery occlusion--hysterectomy--myomectomy. CONCLUSION: The clinical guideline was prepared after the analysed data were supplied using the material and criteria of Society of Obstetricians and Gynaecologists of Canada (SOGC) for the management of uterine fibroids.

Dopamine 2 and somatostatin 1-5 receptors coexpression in clinically non-functioning pituitary adenomas.

This study investigated quantitated expression of dopamine 2 receptor (D2R) and somatostatin receptors of the five types (SSTR1-SSTR5) in a large series of clinically non-functioning pituitary adenomas (CNFAs). Co-expression of these receptors in individual adenomas was studied as well as correlation between receptor types. Adenoma tissue from 198 patients who underwent surgery for CNFAs was analyzed by immunohistochemistry and quantitative real-time PCR. D2R and SSTR1-3 mRNA was expressed in all 198 adenomas. SSTR4 and SSTR5 were detectable in 85 % and 61 % of adenomas, respectively. Expression of D2R was significantly higher than that of the somatostatin receptors. The median relative expressions were as follows from highest D2R >> SSTR3 > SSTR2 > SSTR1 > SSTR5 > SSTR4. High relative expression (ratio to beta-glucuronidase mRNA > 1) of D2R was found in 60 % of tumors, high expression of SSTR1 in 7.5 %, SSTR2 in 7 %, SSTR3 in 4 % and SSTR5 in 0.5 %. The quantity of D2R correlated positively with expression of SSTR2 and SSTR3, and negatively with SSTR1 and SSTR5. Among histological adenoma types, SSTR1 was significantly higher in null-cell adenomas and SSTR3 was lower in silent corticotroph adenomas. In conclusions, in CNFAs, high expression of somatostatin receptors is much less common than that of D2R, and co-expression of both these receptors is exceptional. D2R and SSTR3 seem to be the most promising targets for pharmacological treatment.

A brain imaging (single photon emission computerized tomography) study of semantic and affective processing in psychopaths.

Psychopaths have been described as human predators who use charm, intimidation, and violence to control others and to satisfy their own needs. Underlying their propensity to violate social norms and expectations is a profound lack of empathy, guilt, or remorse, affective processes that have long resisted scientific investigation. Using brain imaging technology we found that psychopaths differed from nonpsychopaths in the pattern of relative cerebral blood flow during processing of emotional words. The results were consistent with the hypothesis that there are anomalies in the way psychopaths process semantic and affective information.

Differential in vivo recovery of sinusoidal endothelial cells, hepatocytes, and Kupffer cells after cold preservation and liver transplantation in rats.

BACKGROUND: The injury resulting from cold preservation/reperfusion primarily affects sinusoidal endothelial cells, while hepatocytes are thought to be less vulnerable; morphological changes and increased cytokine release suggest that Kupffer cells are activated. We evaluated the extent of functional damage to the different cell types in the liver after cold preservation and transplantation. Additionally, we analyzed in vivo the patterns of functional recovery of all three cell types over the first week after transplantation in Lewis rats. METHODS: We evaluated the in vivo uptake of hyaluronic acid, indocyanine green, and radio-labeled sulphur colloid to assess the function of sinusoidal endothelial cells, hepatocytes, and Kupffer cells, respectively. Measurements were performed immediately after transplantation using syngeneic grafts preserved in University of Wisconsin solution for different periods. Functional recovery was monitored in animals receiving grafts preserved for 24 hr over the first postoperative week. RESULTS: We found that hepatocyte were less affected compared with the profoundly damaged endothelial cells. The phagocytic ability of Kupffer cells was, however, also seriously compromised, which suggests a selective down-regulation. Functional recovery occurs in a differential manner during the first postoperative week starting with hepatocytes followed by sinusoidal endothelial cells. Phagocytic function further deteriorates after transplantation before showing improvement. CONCLUSIONS: In viable liver grafts, all cell types recover from preservation/reperfusion injury by the end of the first week after transplantation. The differential time courses of the recovery suggest that successful sinusoidal endothelial cell recovery may depend upon prior hepatocyte regeneration and may involve a paracrine interaction, via cytokines and growth factors.

Three-window transformation cross-talk correction for simultaneous dual-isotope imaging.

UNLABELLED: We developed and tested a new transformation cross-talk correction method for simultaneous dual-isotope SPECT imaging, which uses information from three energy windows in a simultaneous 18F/99mTc cardiac phantom study. METHODS: The method combines the previously reported "three-window" technique and transformation cross-talk correction methods. In the three-window technique, the images from the third energy "scatter" window are usually multiplied by a constant factor to obtain the estimates of the cross-talk. However, such an approach neglects differences in the spatial distribution between cross-talk photons in different energy windows. The transformation method is based on the assumption that the transformations, which convert the images from one energy window into the other energy windows, are known. These transformations were found by measuring the point-spread functions in different energy windows for both isotopes in water. The transformation method takes into account the different spatial distributions of the primary and scatter cross-talk photons in the different energy windows. Here, we are assuming that the imaging system and the image transformations between different energy windows are shift-invariant and linear. Thus, the new method is described by two convolution equations applied in frequency space. In addition to the cross-talk correction, the restoration filters were also applied to the resulting corrected images. The new method was performed on the simultaneous 18F/99mTc cardiac phantom study. Three separate studies were acquired in our phantom study: two single-isotope studies and one dual-isotope study. The single-isotope images were used as references. The contrast between the left ventricle cavity and the myocardium was used in transaxial slices as a parameter to evaluate results of the dual-isotope correction method with restoration. RESULTS: The contrast improvement in the dual-isotope corrected images in both energy windows, i.e., the 99mTc primary window (140 keV) and the 18F primary window (511 keV), was significant. The corrected 511-keV, dual-isotope image had a contrast of 0.74 compared to 0.60, which was the value in the noncorrected dual-isotope image. The improvement of the contrast in the corrected, dual-isotope 511-keV image was exclusively a result of the restoration correction. The restoration-corrected, 511-keV, single-isotope 18F image had the same contrast (0.74). For the dual-isotope, 140-keV transaxial slice, first, the contrast improved from 0.78 to 0.85 after cross-talk correction, and, then, it finally reached 0.92 after additional restoration correction. The contrast in the 140-keV, single-isotope 99mTc image after restoration correction improved from 0.87 to 0.95. CONCLUSION: The three-window transformation dual-isotope correction method with restoration significantly improves the contrast between the left ventricle cavity and the myocardium of the simultaneous 18F/99mTc SPECT imaging.

Effect of haloperidol dose on iodine-123-IBZM brain SPECT imaging in schizophrenic patients.

UNLABELLED: Studies have suggested that antipsychotic drug therapy with haloperidol in schizophrenic patients requires an optimal dose that blocks the brain dopamine D2 receptors. We evaluated the effect of different doses of haloperidol on D2 receptor occupancy in schizophrenia. METHODS: Three normal subjects and three patients with acute schizophrenia had serial brain SPECT imaging studies (every 5 min) for 3 hr following the injection of [123I]IBZM. The patients had IBZM studies off medication and at different doses (1-10 mg) of haloperidol. RESULTS: The basal ganglia (BG) were well visualized in normals and in schizophrenics off medication. After haloperidol therapy, SPECT images showed qualitatively diminished activity in the basal ganglia. ROIs were drawn over the basal ganglia and cerebellum (CE). The results were expressed as BG/CE ratios. At 2 hr postinjection of IBZM, the mean BG/CE ratio in normals was 1.75 +/- 0.025. In schizophrenics, the BG/CE ratio off medication was 1.54 +/- 0.12. The BC/CE ratio showed an inverse relationship to haloperidol dose; 1.46 at 1 mg, 1.25 at 4 mg and 1.05 at 10 mg, respectively. CONCLUSION: These results demonstrate that IBZM brain SPECT imaging studies are potentially useful to relate the antipsychotic drug D2 receptor occupancy with the administered dose in schizophrenic patients and may ultimately help optimize antipsychotic treatment.

Clinical utility of technetium-99m-teboroxime myocardial washout imaging.

UNLABELLED: The purpose of this study was to evaluate the clinical utility of 99mTc-teboroxime myocardial washout imaging. The differential washout after a single tracer injection has been proposed as an alternative for characterization of the perfusion defects. METHODS: Fifty-six patients received 5-min adenosine infusion. The stress dose of 99mTc-teboroxime was injected at 4.5 min and stress imaging with a single-headed SPECT gamma camera was started at 6 min, washout imaging followed immediately. At 20 min, the rest tracer dose was injected at rest and imaging was started at 21.5 min. The reversibility of the perfusion defects on the washout and rest images was compared visually and quantitatively. RESULTS: There was no statistical difference in the number of stress defects that improved on the washout and rest images. The visual interpretation of the perfusion abnormalities was confirmed by quantitative analysis of relative segmental activity. CONCLUSION: Thus, 99mTc-teboroxime-adenosine washout myocardial perfusion imaging can be safely and quickly accomplished. Detected reversibility of the perfusion defects did not significantly differ from reversibility observed on the rest images.

Adrenal glands imaging with indium-111-DTPA-D-Phe1-octreotide following ACTH therapy.

Somatostatin receptors have been identified in a variety of neuroendocrine tumors and activated leukocytes. A high density of somatostatin receptors is also present in most intestinal intramural veins of patients with inflammatory bowel disease. We present a case of a 25-yr-old female with severe Crohn's disease unresponsive to medical therapy, including adrenocorticotropic hormone (ACTH) administration. The patient underwent (111)In-DTPA octreotide scintigraphy to evaluate the potential role of somatostatin receptor imaging in inflammatory bowel disease. Despite the lack of significant somatostatin receptors in the affected bowel, an unexpected prominent activity of (111)In-DTPA octreotide was noted in the adrenal glands on the SPECT images, presumably resulting from excessive stimulation by ACTH. The expression of somatostatin receptors in the stimulated adrenals may be used to image other adrenal pathologies and could potentially indicate response to therapy.