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Biomedical subjects

H Rösler

Publications and source records attributed to H Rösler.

At least 19 recordsLinked to original sources
PubMed1998

Primary cervical malignant teratoma with a rib metastasis in an adult: five-year survival after surgery and chemotherapy. A case report with a review of the literature.

We report a case of a man presenting with a cervical malignant teratoma and a chondrosarcomatous rib metastasis. He was alive and free of recurrence five years and 10 months (= 70 months) after resection of the primary mass, followed by chemotherapy and subsequent resection of the rib tumor. This is the 35th patient reported in the literature and the first description in which an 'adjuvant' or primary chemotherapy was used. Previous patients with a cervical malignant teratoma, reported after lethal outcome, had survivals of one to 22 months (median nine months). In all patients with a preoperative clinical impression of an aggressive, differentiated or undifferentiated malignancy, the definite diagnosis of teratoma could only be made histologically. By analogy to germ cell tumors, the prognosis of malignant teratoma might be improved if complete excision is combined with new, adjuvant chemotherapy protocols for germ cell tumors. Lessons learned from this case are placed in the context of germ cell tumors in general and of non-gonadal malignant teratomas in particular.

Adult↗
PubMed1997

[Choice of therapy in unifocal functional autonomy of the thyroid gland with hyperthyroidism].

Over the last 20 years, unifocal functionally autonomous nodes (UFA) of the thyroid have accounted for more than one third of all patients with hyperthyroidism in the former iodine-deficient and goiter-endemic region of Bern. This situation calls for a special diagnostic approach, i.e. etiologic diagnosis of any solitary nodule and careful consideration of therapy in contrast to regions with iodine excess where UFA is very rare, such as the USA. Therapy is recommended even where hyperthyroidism is still latent (blocked TRH test, normal TT3 and TT4) and reliably leads to subjective and objective improvement even in oligosymptomatic individuals. The safe and easy radioiodine therapy (RIT) is preferred in elderly patients with associated conditions. Surgical resection is recommended chiefly where malignancy is suspected or RIT is technically inappropriate. Both methods produce prompt eradication of the source of hyperthyroidism. The most frequent complication is hypothyroidism requiring lifelong follow-up.

Adolescent↗
PubMed1997

[Scintigraphic method in the quantification of morphological and functional changes of thyroid autonomy before and after iodine radiotherapy].

The regional excess of function and cell mass in potentially "toxic" thyroid areas with nonimmunogenic hyperthyroidism (NIH) (unifocal [UFA, previously "toxic adenoma"] and multifocal functional autonomies [MFA or "toxic goiter"]) are quantified by an enhanced diagnostic method: double isotope subtraction scintigraphy (Ssc) with radioiodine and 99mTc-MIBI. In 125 patients, a toxicity index T was derived from the Ssc (*J-*MIBI), and a cell density index Q from the *MIBI image. The median value of T, as an expression of the regional autonomous excess function (165 in UFA, 15 in MFA), by far exceeded the median value of Q (3.8 in UFA, 2.0 in MFA). The significant (p < 0.001) effects of radioiodine therapy (RIT) were monitored by the changes towards normalization of T and Q in 53 patients in follow-ups 3 and 9 months thereafter. Our aim was (a) to extend the conventional field of measurement of NIH-hyperthyroidism with the scintigraphically quantified function and morphology, and (b) to compare the return to euthyroid state with scintigraphic scarification of the functionally autonomous areas.

Contrast Media↗
PubMed1997

[Why is iodine deficiency once again present in the Berne region?].

Owing to the progressive iodination of salt in Switzerland (5, 10, 20 mg KI/kg in the years 1922, 1965, 1980), iodine deficiency in former endemic goiter regions had nearly disappeared. In several areas of the country, urinary iodine had increased from below 30 micrograms/24 h (1920) to > 100 micrograms/g creatinine (1981-1990). In 1991-1992, however, the 24-h-iodinuria in a subgroup of 160 examinations out of a total of 289 persons in Berne was again insufficient (norm > 150 micrograms J/24 h): mean 121 micrograms/24 h (82 micrograms/l), median 107.8 micrograms/24 h (67 micrograms/l). Follow-up of one proband in 1991-1992 (n = 9) and 1996 (n = 11) yielded average 24-h-iodinurias in the slightly deficient domain of (mean +/- SD) 104 +/- 57 micrograms/ 24 h (75 +/- 30 micrograms/l) and 103 +/- 27 micrograms/24 h (44 +/- 17 micrograms/l) respectively, with a wide range (45-258 micrograms l/24 h globally). Possible reasons for the decreasing iodide intake in recent years, resulting in the 1990s in a marginally deficient supply, are reduced intake of salt in recent decades, increased consumption of foodstuffs prepared with non-iodized salt, dietary diversification, and frequent meals away from the family table. Therefore, intake of non-iodized salt should be avoided in Switzerland.

Adult↗
PubMed1996

Noninvasive differentiation of meningiomas from other brain tumours using combined 111Indium-octreotide/99mtechnetium-DTPA brain scintigraphy.

We have studied prospectively 47 patients with CNS tumours including 16 meningiomas and 33 other tumours using combined 111In-octreotide and 99mTc-DTPA brain scintigraphy. 111In-octreotide scintigraphy was used to image somatostatin receptors (SSR) and 99mTc-DTPA scintigraphy was used to assess the integrity of the blood-brain barrier (BBB). A total of 32 tumours (65%) were detected. All SSR positive tumours also had positive 99mTc-DTPA scans and all SSR negative tumours were negative on 99mTc-DTPA scans. Among the tumours located outside the BBB, all meningiomas and two out of six schwannomas were positive on combined SSR/99mTc-DTPA scintigraphy. Among the tumours located inside the BBB, seven out of nine gliomas grade I-III were negative, whereas all glioblastomas were positive. Other positive tumours included one malignant non-Hodgkin lymphoma and two cerebral metastases. SSR scintigraphy alone was non-specific in the diagnosis of meningiomas, as 16 non-meningiomatous tumours also had positive SSR scans probably due to a breakdown of the BBB (excluding the malignant lymphoma). Measuring the tumour-to-background ratio on SSR scans improved specificity, but sensitivity was decreased below 70% because some meningiomas were only slightly positive. Only the ratio of SSR scintigraphy to conventional 99mTc-DTPA brain scintigraphy (SSR-to-BS index) allowed a reliable differentiation of meningiomas from other CNS tumours, most notable from schwannomas (sensitivity: 94%; specificity: 100%). Our results support the usefulness of combined SSR and conventional brain scintigraphy in the noninvasive pre-operative diagnosis of meningiomas.

Adolescent↗
PubMed1996

Separation of autonomous function from cell density in non-immunogenic hyperthyroidism--II. quantified comparison before and after radioiodine therapy.

Regional autonomous cell mass (Q: cell density ratio) and function (T: toxicity index) were compared by double isotope parametric thyroid scintigraphy (Als et al., Nucl. Med. 1995; 34) in 53 patients with non-immunogenic hyperthyroidism before and after radioiodine therapy (aRIT) and showed a break-down (medians) of Q: 4.3-->1.0 (toxic adenomas: TA), 2-->1.1 (multifocal functional autonomies: MFA)(p < 0.0001) as of T: 96-->1.7 (TA), 15-->1.1 (MFA) (p < 0.001). Five functional aRIT patterns resulted: euthyroidism (n = 37, 70%), at half with scarred/non-scarred autonomous areas (low/higher T, respectively), primary hypothyroidism (n = 4), residual hyperthyroidism (n = 7), secondary hyperthyroidism (n = 5). The last two groups with persistent subnormal TSH values were clearly separated by divergent T, thyroxine and triiodothyronine levels. A resulting T > 1 may represent a clinically sub-critical mass of residual autonomous tissue. This new technique facilitates individual pretherapeutic evaluations and aRIT quality control.

Follow-Up Studies↗
PubMed1995

[Toxic adenomas of the thyroid gland becoming less frequent in Berne].

The frequency distribution of immunogenic and non-immunogenic hyperthyroidism (IH, NIH) was evaluated retrospectively in the former endemic goiter area of Berne over a 15-year period (1976, 1982, and 1991). Out of 12,320 patients referred for thyroid examinations, 9.1% were hyperthyroid. NIH still predominates with a constant frequency of 59%; but the ratio between toxic adenomas (TA) and multifocal functional autonomies (MFA) was significantly inversed, from 2.6 over 0.9 to 0.4. The frequency of TA decreased from 41% to 17% and that of MFA increased from 16% to 38%. The arithmetic mean age at diagnosis was constant: 53.9 (IH), 61.5 (TA) and 67.5 years (MFA). The decreasing frequency of TA over the last 15 years is explained by an increased but still insufficient iodine supply.

Aged↗
PubMed1995

The impact of W. K. Röntgen's discovery on the use of internalizable sources of ionizing energy in diagnostic and therapeutic nuclear medicine.

The early history of cathode rays, X-rays and a third kind of natural radiation from several minerals and atomic fission is described. In this way the fundamental concept of radioactivity, laws of decay and atomic models were developed. With artificial radioactive isotopes, new tailored radiopharmaceuticals could be introduced into metabolic research, medical diagnostics and therapy. Von Hevesy's concept of the dynamic state of body constituents led to examination of the locations and movements of labelled atoms and molecules as a function of time. That was the birth of nuclear medicine. The principles and value at the molecular level of several specific tracer studies in research and diagnostic or therapeutic use are explained. Typically, diagnostic tests with tracer agents are non-invasive and have low radiation exposure. Competing with other diagnostic and therapeutic modalities, nuclear medicine is a speciality in its own right. But there are moves to classify it as a subspecialization of other organ-oriented clinical disciplines. That is a misunderstanding of the radiologist's role and does not answer the question: What is the best way of working for the patient? New horizons in diagnostic modalities, biochemistry, immunology, imaging and the use of immunogenic therapeutic agents demand a continuous cooperation within interdisciplinary teams. That is as necessary with radiologic departments, participating in changed organizational structures, as with other clinical departments.

Humans↗
PubMed1995

The instability of dietary iodine supply over time in an affluent society.

In the Bernese region, where goiter was formerly endemic, alimentary salt has been supplemented by increasing amounts of potassium iodide (KI): 5, 10, 20 mg KI/kg in 1922, 1965 and 1980 respectively. Ioduria rose from < 30 micrograms I/g creatinine in 1920 to > 100 micrograms I/g creatinine in the 1980s. In 1992 ioduria was estimated in 55 healthy volunteers (group A and individual B) and 234 thyroid carcinoma patients after thyroidectomy: hypothyroid patients with (C) and without thyroid remnants (D) and euthyroid patients on T4 substitution (E). The arithmetic mean iodine excretion of the healthy volunteers in group A and individual B was found to be 87 +/- 40 micrograms I/g creatinine. This is insufficient according to the recommendations of the WHO. In all groups, the iodine excretion reached the recommended level only in some members: 24% (A, B), 19% (C), 38% (D) and 81% (E). It was thought in the 1980s that in a formerly iodine-deficient society, iodinated salt would continue to provide an adequate supply of iodine. However, iodine intake in this affluent society has proved to be unstable. This can be attributed to modifications of eating habits, which include a reduction of total salt consumption, combined with a growing consumption of manufactured food of cosmopolitan origin, prepared using salt containing little or no iodine.

Adolescent↗
PubMed1995

Renal pathology after arterial yttrium-90 microsphere administration in pigs. A model for superselective radioembolization therapy.

RATIONALE AND OBJECTIVES: To test the selectivity of tissue damage in radioembolization, the authors performed an experimental study using superselective administration of yttrium-90 particles to deliver up to 100 Gy to the porcine kidney. Patterns and severity of damage in test organs were compared with controls, and the feasibility of this model is discussed. METHODS: Eight sows were included in the study. Bio-Rex 70 particles were applied via selective catheterization of the renal artery. Four pigs received inactive particles and four pigs received active particles. Organ distribution and shunting of yttrium-90 were determined, and kidney damage patterns were histologically analyzed. RESULTS AND CONCLUSIONS: The model demonstrates that yttrium-90-labeled resin particles can superselectively be applied. Retention of beta activity in the target organ was more than 95%. In addition to tissue shrinkage from mechanical obstruction, considerable damage ensued mainly by radiation-induced arterial necrosis and arteritis.

Animals↗
PubMed1995

Congestive hypersplenism: treatment by means of radioembolization of the spleen with Y-90.

Radioembolization of the spleen with yttrium-90 was performed in a patient with severe thrombocytopenia attributable to congestive hypersplenism. Follow-up included performance of serial contrast material-enhanced computed tomographic studies for 13 months. Splenic volume decreased from 1,400 to 470 cm3. The platelet count increased to almost normal levels. No complications were observed. Splenic radioembolization merits further investigation in selected patients.

Aged↗
PubMed1995

Immunogenic and non-immunogenic hyperthyroidism. Recent trends in prealpine Switzerland and in coastal Poland.

Annual occurrences of immunogenic (IH) and non-immunogenic hyperthyroidism (NIH) between Berne (1976, 1982, 1991) and Szczecin (1973, 1980, 1991) were compared. Out of 21,025 patients referred for thyroid examinations, 10.1% (average) were hyperthyroid. In Berne (former endemic goiter region) and Szczecin (without goiter endemicity) IH occurred in 41% and 68%, NIH in 59% and 32% of hyperthyroid patients, respectively. Within a stable incidence of NIH in Berne, toxic adenomas (TA) decreased from 41% (1976) to 17% (1991) (p < 0.005). In Szczecin, where iodine deficiency is in an early stage, the TA frequency did not change significantly: from 24% (1973) to 28% (1991). Increases of TA or of multifocal functional autonomy apparently "mark" incipient or, respectively, decreasing deficiencies in nutritious iodine. Hyperthyroid patients in Berne compared to Szczecin were older, both with IH (54 versus 45 y) and NIH (65 versus 52 y). Age at diagnosis was stable in Berne but increasing (p < 0.05) in Szczecin (from 43 to 52 y).

Adenoma↗
PubMed1995

Optimal sampling times for OIH-clearance calculations using a two-compartment/two-sample method.

Orthoiodohippurate (OIH) clearance data obtained with the two-compartment/two-sample method of Lear which uses varying sampling time combinations, were compared with those of the reference two-compartment/multi-sample method of Sapirstein. A total of 35 studies were performed in 33 adult patients. The OIH clearance values determined by the reference method ranged from 107 to 883 ml/min/1.73 m2, with a median of 406 ml/min/1.73 m2. It was ascertained that the precision of the Lear method is partially dependent upon the sampling time combination. The most reliable results with the Lear method in this patient population were obtained by taking a first sample at approximately 8 min p.i., and a second sample at 32 min p.i. or later.

Adult↗
PubMed1995

Somatostatin receptor scintigraphy in central nervous system tumors: role of blood-brain barrier permeability.

UNLABELLED: Somatostatin receptors are expressed in meningiomas and low-grade gliomas, raising the hope that scintigraphy with 111In-DTPA-D-Phe1-octreotide might be helpful in the in vivo localization, differential diagnosis and postoperative/postradiotherapy brain tumor follow-up. METHODS: Indium-111-DTPA-D-Phe1-octreotide scintigraphy and brain scintigraphy using 99mTc-DTPA as a nonspecific tracer for blood-brain barrier integrity were simultaneously performed in 60 patients with CNS tumors using dual-isotope acquisition mode SPECT. For 23 patients, the scintigraphic findings were also compared with in vitro somatostatin receptor autoradiography of surgical biopsy specimens. RESULTS: In meningiomas (located outside the blood-brain barrier), the somatostatin receptor scan showed all tumors and scintigraphic signal intensity correlating with in vitro SSR density positive in all meningiomas. Less contrast was seen on 99mTc-DTPA scans. In all tumors inside the blood-brain barrier, the 111In-DTPA-D-Phe1-octreotide scan visualized the tumors with a disrupted blood-brain barrier, as seen by 99mTc-DTPA scintigraphy. Discrepancies, however, were observed between somatostatin receptor scintigraphy and in vitro receptor autoradiography. CONCLUSION: Combined somatostatin receptor and 99mTc-DTPA scintigraphy may be helpful for noninvasive differentiation between meningiomas and other CNS tumors. False-negative scans were observed as a result of shielding by the intact blood-brain barrier. Interpretation of negative and positive somatostatin receptor scans in CNS tumors must therefore be done with caution.

Adolescent↗
PubMed1995

Separation of autonomous function from cell density in non-immunogenic hyperthyroidism. I. Quantification by double-isotope parametric scintigraphy.

UNLABELLED: A new quantitative subtraction method of thyroid scans is proposed which shows that regional function (F) by far exceeds regional cellularity or cell density (C) in potentially toxic thyroidal areas of non-immunogenic hyperthyroidism (NIH). METHODS: A multistep processing of radioiodine and MIBI thyroid scans of patients with non-immunogenic hyperthyroidism led to normalized images of regional function excess and of perinodular enhancement. Two numeric factors were derived from regions of interest: Q (cell density ratio) comparing MIBI uptake in autonomous and suppressed areas and T (toxicity index): the maximal F/C contrast. RESULTS: Q never exceeded 61; T, however, expanded toxicity levels over a range of 6-8735 with toxic adenomas (median = 165) and with hot areas of multifocal functional autonomy (median = 15). T was weakly correlated to serum TT3 (r = 0.41), but not to autonomous tissue mass, ultrasonographic or cytologic criteria. CONCLUSIONS: T is governed by inherent features of autonomous tissue and the response of the imbedded thyroid tissue to TSH stimulation. This standardized technique consolidates experiences from visual analysis; the huge T range mirrors the natural evolution from compensated autonomy towards hyperthyroid, decompensated stages.

Diagnosis, Differential↗
PubMed1994

[Methods for the superselective radioembolization of liver tumors with 90yttrium-resin particles].

An improved technique for radioembolization of non-resectable liver tumours is described. 90yttrium-labelled Bio-Rex-70 particles which show high stability and good tissue tolerance are applied superselectively via the tumour-feeding artery using a microcatheter. The procedure includes both diagnostic and therapeutic angiography. Angiography is complemented by angioscintigraphy (99mTc-MAP) and an i.v. 99mTc-colloid scan of the liver. Thus it is possible pretherapeutically to evaluate tumour volume and dose distribution both in and outside of the liver, and in the lung due to shunt. These estimates were re-evaluated posttherapeutically. Radioembolization can thus be quantified and the doses absorbed by the tumour as well as the liver and lung can be calculated.

Adult↗
PubMed1994

Superselective radioembolization of hepatocellular carcinoma: 5-year results of a prospective study.

Twenty patients with unresectable hepatocellular carcinoma (HCC) were followed up to 5 years after transarterial radiotherapy with 90Y-resin particles. Diagnostic radioembolizations of 99mTc-macroaggregates facilitated scintigraphic assessment of activity distribution, dose evaluation and final procedural verification. The overall survival rates were 56, 38 and 14% (after 1, 2 and 3 years, resp.). Patients with unifocal HCC and a single feeding artery (n = 7) even presented 83, 67 and 40% (2 alive after 2.75 and 4 years). With multiple arteries (n = 7), the longest survival was 26 months. Patients with multifocal HCC survived up to 33 months after selective radioembolization. Quality of life was improved in all. Survival was positively correlated with absorbed dose but residual/recurrent tumour occurred even after > or = 300 Gy. Post-treatment symptoms were minimal (35 applications), pulmonary shunt rates were correctly predicted and pulmonary complications avoided.

Adult↗