Radioiodine therapy during an unknown remained pregnancy and radiation exposure of the fetus. A case report.

PURPOSE: A papillary thyroid cancer staged as p T2N3M0 was treated in a 28-year-old woman by surgery, percutaneous radiation and radioiodine therapy (10 single applications ranging from 3300 to 3840 MBq with an average radioactivity of 3350 MBq). In the course of radioiodine therapy an attended gynaecologist found the woman pregnant in the 24th week of gravidity. Because the pregnancy remained unknown until this time radioiodine was administered during the 2nd and the 22nd week of pregnancy, each time 3700 MBq. Because of the risk of malformations this pregnancy was interrupted after consultation and taking the recommendations of the so-called Danish rule as a basis for the decision. METHODS: Ovarian and fetal doses as well as the fetal thyroid exposure has been estimated as exactly as possible using data at hand. The fetus was studied with regard to possible consequences of radiation exposure by pathologico-anatomical, cytogenetic and radiobiological methods. RESULTS: The accumulated ovarian doses resulting from the radioiodine administrations before pregnancy was estimated to 2200 mGy, the fetal doses resulting from the two administrations during pregnancy to 250 mGy in each case, and the fetal thyroid dose to between 90 Gy and 900 Gy for the 2nd therapy during pregnancy. In the fetus the most important changes were found within the thyroid gland (atrophy, sclerosis, subcapsular interstitial fibrosis, necrobiosis of follicular epithelial cells). On the other hand, analysing the karyotype using dermal fibroblastic cell cultures, no radiation induced chromosomal aberrations were seen. CONCLUSION: Despite of all precautionary measures it seems to be conceivable that in extremely rare cases--in our 35-year experience with more than 20,000 radioiodine therapies only the present case--an early pregnancy may remain undetected. The results of these studies give useful information on effects to be expected as a result of radioiodine application during certain periods of pregnancy. They may help to extend the radiobiological knowledge with regard to the fetal period.

[Kidney radionuclide diagnosis in the evaluation of clinical problem cases in pediatrics and nephrology]. / Nuklearmedizinische Nierendiagnostik zur Klärung klinischer Problemfälle in Pädiatrie und Nephrologie.

An internistically and nephrologically as well as paediatrically well preexamined and selected group of patients in particular cases needs for the judgment of the renal function and capacity a nuclear-medical diagnostics which passes these preexaminations. Renal sequence scintigraphy including the trend scintigraphy and examinations of the renal clearance with side-separated judgment of the renal clearance with side-separated judgment of the function are at our disposal. The indication of these techniques and the value of evidence are demonstrated with the help of problem cases. As problem cases are demonstrated a child with glomerulonephritis, a female patient with renal failure post partum before and after haemodialysis including the observation of the course a female patient with localized inflammatory disease as well as a patient with kidney tumour and cirrhosis of the kidney. It is shown that nuclear-medical techniques recognize relatively discrete, but also severe pathological changes and are necessary within a complex judgment of the function, the quantitative establishment of the functional and compensatory capacity of the kidneys as well as for the planning of therapy and the control of the course.

[Fundamental investigations for the deposition of aerosols from radioactive solutions in the upper and lower airways (author's transl)]. / Grundsätzliche Untersuchungen zur Deponierung von Aerosolen aus radioaktiven Lösungen in den Atemwegen.

By means of 99mtechnetium diphosphonate and a scintillation camera we measured the deposition of aerosols. During normal breathing rhythm and without leading the aerosol by valves the retention in the lower airways was on an average of 5.6%, that is 0.07 ml/min. By installation of suitable valves for in- and expiration and mouth tubes, deep and complete expiration with breath holding the retention of the aerosol increases to 17.3-13.8% (0.22-0.17 ml/min); with normal breathing the deposition was only 9%. In the upper airways we found the following deposition rates: Nose/hypopharynx (inhalation via mask) 2.6%; Mouth and pharynx (after rinsing) 1.6%; Larynx 0.1%. A considerable part remains in the inhalation system; by special variations we were able to reduce this portion of the aerosol. After inhaling electro-aerosols (4 kv) the deposition in the lungs was 5.6%; the more the charge was reduced the more the deposition of the aerosol in the lung increased.

[Deposition of aerosols into the airways (author's transl)]. / Deponierung von Aerosolen in den Atemwegen.

The rate of powder absorbed in the lung greatly depends on the particle diameter, and amounts to 40--50% for 1 micrometer particles and 15--20% for 5 micrometer particles. Of importance for therapy was the information that single breath will deposit in the lung 15% of a powder aerosol of 2 micrometer diameter. The liquid aerosols as prevalently used in the therapy, were retained in the lung at a rate of 15% of the original amount when using ultrasonic apparatus. If calculated per minute of inhalation time, the amount absorbed by the lung amounted to 0.2 ml and that by the upper respiratory tract to 0.06 ml. Best deposition in the lung was obtained when inhaling in a closed system with valve-controlled aerosol stream, when using a mouthpiece, and when the test person inhaled with low respiratory rate, deep inspirations, short respiratory pause and complete exspiration. Mark inhalation with closed mouth gave only one tenth of the lung deposition reached with the breathing method described. The use of a mask showed good results, however, when the test person was breathing with open mouth. Only 0.07 ml/min were retained with jet nebulizer and mouth respiration. Combination with intermittent pressure respiration showed no convincing results.

[Simultaneous determination of effective renal plasma flow and glomerular filtration rate using a double isotope technic--determination of the filtration fraction]. / Simultane Ermittlung des effektiven renalen Plasmastromes und des Glomerulumfiltrates mit Hilfe einer Doppelisotopentechnik--Bestimmung der Filtrationsfraktion

A method for the simultaneous determination of the effective renal plasma flow and of the glomerular filtration rate with the help of 131J-o-iodohippuric acid and 169Yb-DTPA using a double isotopic technique is described. Apart from this the method serves for the establishment of the filtration fraction. 40 patients with different clinical pictures (glomerulonephritis, pyelonephritis, cystic kidneys, stenosis of the renal artery) were examined. The clearance values established by us were in the areas characteristic for the clinical pictures. Pathological conditions could be established which are not yet characterized by an increase of the fixa of the urine in the serum. By the determination of the filtration fraction differential-diagnostically important insights are afforded. The examination is methodically simply to be performed and is of little stress for the patient. Therefore it seems to be suitable for the routine examination.