[99mTc-MIBI scintigraphy of hypofunctional thyroid nodules. Comparison of planar and SPECT imaging]. / 99mTc-MIBI-Szintigraphie hypofunktioneller Schilddrüsenknoten. Vergleich von planarer und tomographischer Technik.

UNLABELLED: 99mTc-MIBI-scintigraphy allows to assess the dignity of hypofunctional thyroid nodules. A concordant pattern in MIBI- and pertechnetate-scintigraphy excludes malignancy with high accuracy. For increased MIBI-uptake histological evaluation is advised. The assessment of MIBI-isointense nodules is discussed controversially. Objective of our study was to analyse the prevalence of malignancy for isointense nodules and the diagnostic accuracy of image acquisition in SPECT-technique. PATIENTS, METHODS: MIBI-scintigraphies were analysed retrospectively. Imaging was performed 60 min after intravenous injection of 510 MBq 99mTc-MIBI. Thyroid nodules were assessed as hypo-, iso- or hyperintense compared to the paranodular tissue. RESULTS: 83 of 225 patients underwent thyroid surgery (age 48.6 ± 12.6 years, 72% women). In 12 (14.5%) cases a papillary carcinoma was diagnosed. In planar imaging 12, 34 and 37, in tomographical imaging 16, 21 and 46 nodules, respectively, were classified as hypo-, iso- oder hyperintense. Among hypo-, iso- and hyperintense nodules in planar imaging 1, 5 and 6 carcinomas were found, resp. In tomographical imaging no, 4 and 8 carcinomas were found, respectively. Classification of iso- and hyperintense nodules as "suspicious for malignancy" showed for planar imaging a sensitivity, specificity, NPV and PPV of 91.7, 15.5, 91.7 and 15.6%, for tomographical imaging of 100, 22.5, 100 and 17.9%, respectively. CONCLUSION: Hypofunctional thyroid nodules with iso- and hyperintense MIBI-Uptake have a comparable prevalence of malignancy. Image acquisition in SPECT-technique results in improved diagnostic sensitivity and negative predictive value.

Thyroiditis de Quervain. Are there predictive factors for long-term hormone-replacement?

BACKGROUND: Subacute thyroiditis is a usually self-limiting disease of the thyroid. However, approximately 0.5-15% of the patients require permanent thyroxine substitution. Aim was to determine predictive factors for the necessity of long-term hormone-replacement (LTH). PATIENTS, METHODS: We retrospectively reviewed the records of 72 patients with subacute thyroiditis. Morphological and serological parameters as well as type of therapy were tested as predictive factors of consecutive hypothyroidism. RESULTS: Mean age was 49 ± 11 years, f/m-ratio was 4.5 : 1. Thyroid pain and signs of hyperthyroidism were leading symptoms. Initial subclinical or overt hyperthyroidism was found in 20% and 37%, respectively. Within six months after onset 15% and 1.3% of the patients developed subclinical or overt hypothyroidism, respectively. At latest follow-up 26% were classified as liable to LTH. At onset the thyroid was enlarged in 64%, and at latest follow-up in 8.3%, with a significant reduction of the thyroid volume after three months. At the endpoint the thyroid volume was less in patients in the LTH group compared with the non-LTH group (41.7% vs. 57.2% of sex-adjusted upper norm, p = 0.041). Characteristic ultrasonographic features occurred in 74% of the patients in both lobes. Serological and morphological parameters as well as type of therapy were not related with the need of LTH. CONCLUSIONS: In this study the proportion of patients who received LTH was 26%. At the endpoint these patients had a lower thyroid volume compared with euthyroid patients. No predictive factors for LTH were found.

[Comparison of parameters of time-resolved autofluorescence between healthy subjects and patients suffering from early AMD]. / Vergleich von Parametern der zeitaufgelösten Autofluoreszenz bei Gesunden und Patienten mit früher AMD.

BACKGROUND: A fluorescence lifetime mapper (FLM) was tested for quantitative estimation of early alterations in age-related macular degeneration (AMD) which are assumed to be in cellular metabolism. METHOD: In FLM time-resolved autofluorescence of the fundus is excited by picosecond (ps) laser impulses at 448 nm and detected in 2 spectral ranges (K1=490-560 nm and K2=560-700 nm) by time-correlated single photon counting. The time-dependent decrease in fluorescence intensity was approximated using 3 decay rates. The calculated lifetimes allow a comparison with endogenous fluorophores of cellular metabolism. RESULTS: Initially mean lifetimes were determined for 8 healthy subjects (K1: tau1=118 ps, tau2=584 ps, tau3=2826 ps, K2: tau1=104 ps, tau2=477 ps, tau3=1623 ps). In 15 AMD patients (AREDS categories I and II) the lifetimes were longer (K1: tau1=166 ps, tau2=986 ps, tau3=3309 ps, K2: tau1=137 ps, tau2=583 ps, tau3=1924 ps). The best separation between healthy subjects and patients with early AMD was possible by parameters 1 and 2 in the short-wave channel. Fluorophore-specific alterations in the macula could be demonstrated in isolated cases with advanced AMD. CONCLUSION: Measurements in the 30 degrees fundus field demonstrated that specific alterations were already present even in early AMD and also outside the macula. These act in the neuronal retina, because parameter tau2 is related to this layer. Increases in the lifetime of parameter tau2 in the short wave channel could at least partially be determined by an increase of protein bound NADH, the content of which increases with reduced cellular respiration.

Influence of systolic-pressure-variation-guided intraoperative fluid management on organ function and oxygen transport.

BACKGROUND: Dynamic variables, for example, systolic pressure variation (SPV), are superior to filling pressures for assessing fluid responsiveness. We analysed the effects of SPV-guided intraoperative fluid management on organ function and perfusion when compared with routine care. METHODS: Eighty patients (44 female and 36 male) undergoing elective major abdominal surgery were randomly assigned to a control group [n=40, mean age 66 (sd 10), range 40-84 yr] or SPV group [n=40, age 61 (16), range 26-100 yr] in which intraoperative fluid management was guided by SPV (trigger: SPV>10%). Central venous O2 saturation (ScvO2), lactate and bilirubin, creatinine, indocyanine green plasma disappearance rate (ICG-PDR), and gastric mucosal CO(2) tension were measured after induction of anaesthesia, after 3, 6, 12, and 24 h. RESULTS: Patient characteristics, duration of surgery [5.8 (2.5) vs 5.4 (2.5) h], and infusion volumes (median 4865 vs 4330 ml) were comparable between the groups. At 3 and 6 h, SPV (P=0.04, P=0.01) and Deltadown (P=0.005, P=0.01) were significantly higher in the control group. Oxygen transport and organ function were comparable: baseline and 24 h values for ICG-PDR: 28.5 (7.9) and 22.7 (7.8) vs 23.9 (6.9) and 26.1 (5.9)% min(-1), 77.7 (6.6) and 72.6 (5.5) vs 79.3 (7.1) and 72.8 (6.7)% for ScvO2 and 1.0 (0.4) and 1.2 (0.6) vs 0.9 (0.2) and 1.3 (0.5) mmol litre(-1) for lactate. Length of mechanical ventilation, ICU stay, and mortality were comparable. CONCLUSIONS: In comparison with routine care, intraoperative SPV-guided treatment was associated with slightly increased fluid adminstration whereas organ perfusion and function was similar.

Towards metabolic mapping of the human retina.

Functional alterations are first signs of a starting pathological process. A device that measures parameter for the characterization of the metabolism at the human eye-ground would be a helpful tool for early diagnostics in stages when alterations are yet reversible. Measurements of blood flow and of oxygen saturation are necessary but not sufficient. The new technique of auto-fluorescence lifetime measurement (FLIM) opens in combination with selected excitation and emission ranges the possibility for metabolic mapping. FLIM not only adds an additional discrimination parameter to distinguish different fluorophores but also resolves different quenching states of the same fluorophore. Because of its high sensitivity and high temporal resolution, its capability to resolve multi-exponential decay functions, and its easy combination with laser scanner ophthalmoscopy, multi-dimensional time-correlated single photon counting was used for fundus imaging. An optimized set up for in vivo lifetime measurements at the human eye-ground will be explained. In this, the fundus fluorescence is excited at 446 or 468 nm and the time-resolved autofluorescence is detected in two spectral ranges between 510 and 560 nm as well as between 560 and 700 nm simultaneously. Exciting the fundus at 446 nm, several fluorescence maxima of lifetime t1 were detected between 100 and 220 ps in lifetime histograms of 40 degrees fundus images. In contrast, excitation at 468 nm results in a single maximum of lifetime t1 = 190 +/- 16 ps. Several fundus layers contribute to the fluorescence intensity in the short-wave emission range 510-560 nm. In contrast, the fluorescence intensity in the long-wave emission range between 560 and 700 nm is dominated by the fluorescence of lipofuscin in the retinal pigment epithelium. Comparing the lateral distribution of parameters of a tri-exponential model function in lifetime images of the fundus with the layered anatomical fundus structure, the shortest component (t1 = 190 ps) originates from the retinal pigment epithelium and the second lifetime (t2 = 1,000 ps) from the neural retina. The lifetime t3 approximately 5.5 ns might be influenced by the long decay of the fluorescence in the crystalline lens. In vitro analysis of the spectral properties of expected fluorophores under the condition of the living eye lightens the interpretation of in vivo measurements. Taking into account the transmission of the ocular media, the excitation of NADH is unlikely at the fundus.

[Alterations in autofluorescence decay time in the fundus after oxygen provocation]. / Veränderungen der Autofluoreszenzlebensdauer am Fundus nach Sauerstoffprovokation.

BACKGROUND: Alterations in the equilibrium of redox pairs of co-enzymes give information about the metabolic state in the citric acid cycle as well as in the respiratory chain. Fluorescence properties are different between the reduced and oxidised states of co-enzymes so that a change of the oxygen partial pressure can be sensitively detected in the tissue. Therefore, it was investigated whether the autofluorescence of co-enzymes is detectable in the living fundus. METHOD: The provocation of metabolism was realised by inspiration of 100% oxygen. The time-resolved autofluorescence was detected by a single photon counting technique. The decay behaviour of autofluorescence was approximated by a bi-exponential model. For evaluation of the results, histograms of decay times tau(1) and tau(2) were calculated in defined ranges around the macula and optic disc before, during, and after inhaling oxygen. RESULTS: The calculated decay times corresponded in the macula to the decay times of FAD and NADH(+) given in the literature. Connective tissue in the optic disc also showed fluorescence. CONCLUSIONS: Changes in the histograms of decay rates demonstrate that provocation of metabolism is detectable by measurement of time-resolved autofluorescence. This method reveals the evaluation of metabolism at the cellular level as a new diagnostic possibility.

Association of apnea and nonacid gastroesophageal reflux in infants: Investigations with the intraluminal impedance technique.

An association of apnea and gastroesophageal reflux (GER) was proposed previously. However, pH metry as the standard diagnostic tool for GER only measures acid reflux (pH < 4). It is difficult to interpret studies in infants with a presumed association between apnea and GER based on pH metry because the buffering effect of feeding may result in predominantly nonacid GER. The aim of this study was to investigate the temporal association of apnea and GER with the pH-independent intraluminal impedance technique (IMP). Infants with recurrent regurgitation or respiratory symptoms suggestive of apnea were investigated simultaneously with IMP, pH monitoring, and polygraphy. IMP patterns, pH, oronasal flow, and chest wall movement were recorded and analyzed. In 22 infants, 364 GER episodes were recorded by IMP. One hundred and sixty five apneas were documented by visual validation of polygraph records. Forty-nine apneas (29.7%) were associated with GER; 11 (22.4%) of these showed acid reflux (pH < 4). A significant correlation between the time spent apneic and GER was found (P < 0.001). There is marked association between apnea and gastroesophageal reflux in infants. Patients potentially at risk cannot be reliably identified by pH metry. Its exclusive use is therefore not suitable for the detection of all GER-associated apneas in infants. The pH-independent intraluminal impedance technique has proven to be a sensitive diagnostic tool for this approach.

Gastroesophageal reflux and respiratory phenomena in infants: status of the intraluminal impedance technique.

BACKGROUND: The coincidence of recurrent respiratory symptoms and gastroesophageal reflux (GER) is a well-known phenomenon in infants. Twenty-four-hour pH metry is the presumed gold standard of diagnostic tools for this symptom complex, but with this method, only acid (pH <4) and alkaline (pH >7) GER can be detected. Gastroesophageal reflux with an esophageal pH in the physiological range (pH 5-6.8) may represent many cases of clinically relevant GER unrecognized by pH metry. In this study the intraluminal multiple electrical impedance (IMP) procedure for complete registration of GER was compared with pH metry for its diagnostic value in the presence of respiratory symptoms. METHODS: Twenty-two infants with recurrent regurgitation or pulmonary problems were investigated simultaneously with IMP, pH metry, and polygraphy during two feeding periods. Heart rate, oxygen saturation, sleep states, and oronasal flow were recorded, among other parameters. RESULTS: Three hundred sixty-four occurrences of GER were detected by IMP; only 11.4% had a pH less than 4 and were therefore recognized by pH metry. Three hundred twelve (84.8%) occurrences were associated with breathing abnormalities, and 11.9% of these were detected by pH metry. Nineteen instances were accompanied by a decrease of oxygen saturation of more than 10% of the initial value. Only three (15.8%) of these had a pH less than 4. The remaining 16 reflux episodes were recognized by IMP only. After software-aided preselection, 165 instances of apnea were visually validated, 49 of which were accompanied by GER. Thirty-eight (77.6%) of these were exclusively recorded by IMP. CONCLUSIONS: The use of pH metry alone cannot detect most GER incidents accompanied by respiratory symptoms and therefore does not appear to be suitable for this approach. The pH-independent IMP technique promises to be a reliable tool for presumably GER-associated respiratory symptoms.

[Results of treatment of ovarian cancer patients at the Jena University Gynecological Clinic 1974-1983]. / Behandlungsergebnisse bei Ovarialkarzinom-Patientinnen an der Universitäts-Frauenklinik Jena in den Jahren 1974-1983.

In a retrospective analysis 228 patients suffering from ovarian carcinoma were investigated. They had been treated at the Dept. of Gynecology of Jena from 1974 up to 1983. We determined remission rate, remission time, and 5-year survival. Conclusions of our analysis are the following: The incidence and 5-year survival of patients suffering from ovarian cancer are nearly constant during the time interval obtained in this study. Survival will be determined by 38%. Early stages (I and II) were treated only by operation while patients suffering from higher stages (III and IV) were undergone chemotherapy and/or radiotherapy. We obtained value of the remission rate and the 5-year survival rate, comparable to these reported in literature.