Chemical characteristics of wildfire ash across the globe and their environmental and socio-economic implications

The mobilisation of potentially harmful chemical constituents in wildfire ash can be a major consequence of wildfires, posing widespread societal risks. Knowledge of wildfire ash chemical composition is crucial to anticipate and mitigate these risks. Here we present a comprehensive dataset on the chemical characteristics of a wide range of wildfire ashes (42 types and a total of 148 samples) from wildfires across the globe and examine their potential societal and environmental implications. An extensive review of studies analysing chemical composition in ash was also performed to complement and compare our ash dataset. Most ashes in our dataset had an alkaline reaction (mean pH 8.8, ranging between 6 and 11.2). Important constituents of wildfire ash were organic carbon (mean: 204 g kg-1), calcium, aluminium, and iron (mean: 47.9, 17.9 and 17.1 g kg-1). Mean nitrogen and phosphorus ranged between 1 and 25 g kg-1, and between 0.2 and 9.9 g kg-1, respectively. The largest concentrations of metals of concern for human and ecosystem health were observed for manganese (mean: 1488 mg kg-1; three ecosystems > 1000 mg kg-1), zinc (mean: 181 mg kg-1; two ecosystems > 500 mg kg-1) and lead (mean: 66.9 mg kg-1; two ecosystems > 200 mg kg-1). Burn severity and sampling timing were key factors influencing ash chemical characteristics like pH, carbon and nitrogen concentrations. The highest readily dissolvable fractions (as a % of ash dry weight) in water were observed for sodium (18 %) and magnesium (11.4 %). Although concentrations of elements of concern were very close to, or exceeded international contamination standards in some ashes, the actual effect of ash will depend on factors like ash loads and the dilution into environmental matrices such as water, soil and sediment. Our approach can serve as an initial methodological standardisation of wildfire ash sampling and chemical analysis protocols.

Identification and characterization of urinary prenylamine metabolites by means of liquid chromatography-tandem mass spectrometry

Prenylamine is a vasodilator of phenylalkylamine structure and was used for the treatment of angina pectoris, until reports of undesirable effects including ventricular tachycardia led to a decreasing use of the drug in the 1980s. Metabolic N-dealkylation of orally ingested prenylamine can liberate amphetamine in humans and cause positive findings for amphetamine in doping and forensic analysis. In 2010, the World Anti-Doping Agency (WADA) classified prenylamine as a non-specified stimulant according to the 2010 Prohibited List, thus banning its use in sports in-competition. Supporting the development of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) based detection method, a post-administration urine sample following a single oral prenylamine ingestion (Segontin(®) 60 mg) was analyzed for urinary metabolites. The LC-separated analytes were ionized in positive electrospray ionization (ESI) mode and detected as protonated ions using an AB Sciex TripleTOF 5600 quadrupole-time-of-flight hybrid mass spectrometer. Over 40 phase I metabolites were detected, including previously unknown mono- bis-, tris- and tetra-hydroxylated prenylamine, several hydroxylated and methoxylated prenylamine metabolites and (hydroxylated) diphenylpropylamine. Investigation of the collision-induced dissociation behaviours of the metabolites by high resolution/high accuracy mass spectrometry allowed for the assignment of the nature and the site of observed metabolic transformations. The most abundant phase I metabolite was confirmed as p-hydroxy-prenlyamine by chemical synthesis and stable isotope labelling of reference material. An existing routine screening assay based on direct injection and LC-MS/MS analysis of urine was modified and validated according to common guidelines, in order to allow for the detection of p-hydroxy-prenylamine in sports drug testing. The assay demonstrated the ability to detect the target metabolite at 0.1 ng/ml at intra- and inter-day imprecisions below 10%.

Identification of the aromatase inhibitor letrozole in urine by gas chromatography/mass spectrometry

Letrozole (1-(bis-(4-cyanophenyl)methyl)-1,2,4-triazole) is used therapeutically as a non-steroidal aromatase inhibitor (Femara) to treat hormone-sensitive breast cancer in postmenopausal women. For doping purposes it may be used to counteract the adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase the testosterone concentration by stimulation of the testosterone biosynthesis. The use of aromatase inhibitors has been prohibited by IOC/WADA regulations for male and female athletes since September 2001 and January 2005, respectively. Spot urine samples from women suffering from metastatic breast cancer and being treated with letrozole were collected and analysed to develop/optimise the detection system for metabolites of letrozole to allow the identification of athletes who do not comply with the internationally prohibited use of this cancer drug. The assay was based on gas chromatography/mass spectrometry (GC/MS) and the main metabolite of letrozole (bis-4-cyanophenylmethanol) was identified by comparison of its mass spectrum and retention time with that of a bis-4-cyanophenylmethanol reference. The full-scan spectrum, diagnostic ions and a validation of the method for the analysis of bis-4-cyanophenylmethanol are presented.

Massives lokalisiertes Lymphödem - eine seltene Entität

Massive localized lymphedema is a rare disease. Only a few cases have been described in the literature. These monstrous pseudotumors of the subcutis are mostly localized in the inguinal region or at the lower extremity. These tumors often show a slow growth for many years. Besides hernias, lipomatous tumors must be distinguished. The therapy of choice is the excision of the tumor. Relapse is not uncommon in the few cases described in the literature so far. The diagnostic procedure and therapy of an 48-year-old women with a massive localized lymphedema weighing about 22 kg are demonstrated and discussed.

The Trier mummy Paï-es-tjau-em-aui-nu: radiological and histological findings

The ancient Egyptian mummy Paï-es-tjau-em-aui-nu, now on exhibition in the Rheinische Landesmuseum in Trier, Germany, was examined by conventional X-ray radiography, computed tomography, and digital fluoroscopy. In addition, some tissues were biopsied for further histologic identification. Along with some representative images, the peculiarities of the Trier mummy concerning the mummification process are presented.

Identification of the aromatase inhibitor aminoglutethimide in urine by gas chromatography/mass spectrometry

Aminoglutethimide is used therapeutically as an aromatase inhibitor in the treatment of metastatic breast cancer in post-menopausal women. For doping purposes, aminoglutethimide may be used for treatment of adverse effects of an extensive abuse of anabolic androgenic steroids (gynaecomastia) and to increase the testosterone concentration and stimulation of testosterone biosynthesis. The use of aromatase inhibitors has been prohibited for male athletes since September 1, 2001. The purpose of this study was to develop methods for the identification of the parent compound or its main metabolite and the inclusion of this information into established screening procedures in doping analysis. An excretion study was conducted using oral application of one single therapeutic dose (500 mg) of Orimeten. The analysis was performed by gas chromatography/mass spectrometry (GC/MS). Aminoglutethimide is excreted almost totally as unconjugated parent compound and is detectable by different screening procedures for up to 165 h. Most suitable for the detection of aminoglutethimide is the screening procedure for heavy volatile nitrogen-containing drugs ('Screening 2'). However, since only competition samples are analysed in that screening procedure, the additional inclusion of aminoglutethimide in the screening procedure for anabolic androgenic agents ('Screening 4') is recommended. Full mass spectra and diagnostic ions for the analysis of aminoglutethimide are presented.

[Evaluation of renal artery stenosis: comparison of angiography and invasive blood pressure measurement and Doppler ultrasound]

PURPOSE

In the procedure of renal artery angioplasty, the angiographically measured degree of stenosis should be compared with the intraarterial transstenotic blood pressure gradient and pre-interventional Doppler findings.

METHODS

In a total of 46 renal arteries in 35 patients with renovascular hypertension, the angiographic-morphological parameters: "linear", "geometric" and "densitometric" degree of stenosis are compared with the invasive transstenotic blood pressure gradient and the pre-interventional Doppler ultrasound.

RESULTS

All angiographically determined degrees of stenosis ("linear", "geometric" and "densitometric") correlate--moderately--with the transstenotic blood pressure gradient (correlation coefficients: 0.67 ("linear"), 0.65 ("geometric") and 0.49 ("densitometric"), each versus systolic pressure gradient, respectively). Stenoses that are angiographically classified as "low grade" (< 50%) nevertheless have a high number of high transstenotic pressure gradients: 21 of 22 show systolic values > or = 10 mmHg, 13 of 22 even > or = 30 mmHg. All stenoses Doppler sonographically classified as "high or very high grade" (Vmax,syst > or = 3 m/s) are confirmed by angiography and/or pressure measurement.

CONCLUSIONS

Angiography has the tendency to underestimate the degree of renal artery stenosis, especially in "low grade" stenoses (< 50%). However, in those > or = 50% a high transstenotic blood pressure gradient can be taken for granted. If the angiographic degree of stenosis seems uncertain, we recommend measurement of blood pressure gradient.

[Radiology of gastrointestinal stromal tumors (GIST) and a case of Carney syndrome]

Gastrointestinal stromal tumors (GIST) represent an extremely rare group of tumors, which are mostly of smooth muscle origin like leiomyomas, leiomyosarcomas and leiomyoblastomas. With the introduction of immunohistochemical analysis an epithelioid and an autonomic nerve variant can be distinguished. The purpose of this review is to demonstrate the image morphological appearance of these rare tumors together with the pathology based upon a retrospective analysis of five of our own cases since 1997. There are no pathognomonic imaging findings for characterizing a gastrointestinal stromal tumor; however, it should be included in the differential diagnosis if one or multiple large, round or oval, well-delineated gastrointestinal tumors occur in combination with central necrosis. Carney's syndrome is characterized by the syndromal association of a gastrointestinal stromal tumor (originally: gastric leiomyosarcoma) with an extra-adrenal paraganglioma and a pulmonary chondroma. In this rare syndrome, the radiological approach is important to diagnose or rule out the--simultaneous or consecutive--appearance of at least two of the three tumor entities (GIST, extra-adrenal paraganglioma, pulmonary chondroma).

[Computerized tomography and magnetic resonance tomography studies before and after para-tibial fasciotomy]

Paratibial fasciotomy has been employed since 1981 to treat patients with chronic venous insufficiency (CVI) and therapy-resistant leg ulcers with severe lipodermatosclerosis. The characteristic morphological changes in CVI were evaluated shown before and after paratibial fasciotomy using computerized tomography (CT) and magnet resonance tomography (MRT). 10 patients (6 female, 4 male) were examined by CT and MRT pre- and postoperatively. Preoperatively there is a clear thickening of the dermis and subcutaneous field. In addition, the area around the achilles tendon is thickened, the fasciae are enlarged and the muscles of the lower leg show an increase of fatty tissue. A decrease of the cutaneous and subcutaneous thickening is seen postoperatively. The fasciotomy split is visible in most patients.

CT and MRI of Gorham syndrome

Gorham syndrome, also known as massive osteolysis or vanishing bone, is a rare disorder (135 cases reported) leading to extensive loss of bony matrix, replaced by proliferating thin-walled vascular channels. Three histologically proven cases of the disease are reported, including the clinical presentation and modern imaging features with CT (with 3D reconstruction) as well as T1- and T2-weighted MRI. Two cases in young women were located in the pelvis with extensive osteolysis reaching to the acetabulum. The third case in a 2-month-old boy is the youngest case ever reported and involved the humerus. The radiological appearance of the disease is discussed and the importance of the modern imaging methods debated.

Invasive pulmonary aspergillosis. MRI, CT, and plain radiographic findings and their contribution for early diagnosis

A prospective study was conducted in 38 patients with nodular lesions on plain chest radiographs and the clinical suspicion of invasive pulmonary aspergillosis (IPA) to assess the diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT). For early diagnosis of IPA (clinical signs and symptoms < 10 days), CT scans with demonstration of the halo sign had a high sensitivity (16/22) and specificity (8/8). Magnetic resonance imaging performed at the same time revealed a relatively higher sensitivity (22/22), but a very poor specificity (0/8). Gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA) enhanced images did not improve specificity. In the later course of infection (clinical signs and symptoms > 10 days), MRIs showed typical nodular target-like lesions with Gd-DTPA enhancement of the rim area that was not seen in the early course of the disease or in patients with Pseudomonas or staphylococcal infection. In conclusion, MRI findings are not as characteristic as the CT halo sign in diagnosing IPA in the early course of the disease, but the MRI target sign with Gd-DTPA enhancement of the rim area and the "reverse target" on T2-weighted images are strongly suggestive of IPA at a later stage of the disease.

[The value of bone marrow scintigraphy and magnetic resonance tomography in diagnostic imaging of bone marrow]

This article provides an overview of the possibilities and indications for magnetic resonance imaging (MRI) and bone marrow scintigraphy in imaging the bone marrow. After a brief review of the anatomical and physiologic structures of bone marrow, the principles of both methods are described. The radiopharmaceuticals of choice for bone marrow scintigraphy are the newly developed 99mTc-labelled anti-granulocyte monoclonal antibodies. They allow a high-quality, whole-body visualization of haematopetically active bone marrow by specifically targeting granulopoetic bone marrow cells and mature granulocytes. MRI enables us to visualize the bone marrow with high contrast and spatial resolution by assessing different properties of the biological tissue--mainly fat, water, and mineral content. Both methods provide a non-invasive and sensitive approach for imaging the bone marrow in different benign and malignant disorders.

False-positive diagnosis of a pheochromocytoma with I-123 metaiodobenzylguanidine

The rare case of a false-positive scintiscan with I-123 labelled metaiodobenzylguanidine (MIBG) in a patient with suspected pheochromocytoma is reported. Focal accumulation of the tracer in the upper right abdomen, primarily thought to represent a right-sided pheochromocytoma, was subsequently proven to be caused by an ampullary renal pelvis. In cases of unexplained MIBG accumulation the possibility of prolonged retention of the tracer, because of an abnormality of the renal pelvis, should be considered and excluded by ultrasound.

[Early changes in the hip joint following epiphysiolysis of the femoral head. Results of an MRT study]

With the aim of detecting patients at risk of developing coxarthritis, 34 patients were investigated prospectively by MRI 6-14 years after epiphysiolysis for slipped capital femoral head. In particular, cartilage changes were analysed by gradient-echo sequences. In 40% of the hip joints investigated cartilaginous lesions were present, detectable as irregularity and flattening of contour and more rarely as changes in signal intensity. In contrast, only 18% of the radiographs available revealed any pathology. When pelvic X-rays are normal or reveal slight sclerosis, cartilaginous lesions on MRI are considered early signs of coxarthrosis. This combination was seen especially often in patients with a primarily high angle of dislocation and in those who needed treatment by reposition or osteotomy. Only in 8 of the 17 hip joints showing sclerosis on conventional radiograms, sclerosis was also diagnosed by MRI, possibly because of partial volume and susceptibility effects at high field strength. Even with limited spatial resolution, cartilage examination is warranted in young patients in whom early osteoarthritis can be expected.

Pheochromocytomas, multiple endocrine neoplasia type 2, and von Hippel-Lindau disease

BACKGROUND

Pheochromocytoma is a feature of two disorders with an autosomal dominant pattern of inheritance--multiple endocrine neoplasia type 2 (MEN-2) (with medullary thyroid carcinoma and hyperparathyroidism) and von Hippel-Lindau disease (with angioma of the retina, hemangioblastoma of the central nervous system, renal-cell carcinoma, pancreatic cysts, and epididymal cystadenoma). The frequency of these syndromes in patients with pheochromocytoma is not known.

METHODS

In an unselected group of patients with pheochromocytoma, we performed pentagastrin tests, parathyroid hormone assays, computed tomography (CT) or magnetic resonance imaging (MRI) of the brain, ophthalmoscopy, CT imaging of the abdomen, and ultrasonography of the testes. We also screened members of families with MEN-2 or von Hippel-Lindau disease for pheochromocytoma by measuring plasma and urine catecholamines and plasma chromogranin A and by performing abdominal ultrasonography, CT and MRI, and metaiodobenzylguanidine scintigraphy.

RESULTS

Nineteen of 82 unselected patients with pheochromocytomas (23 percent) were carriers of familial disorders; 19 percent had von Hippel-Lindau disease and 4 percent had MEN-2. Prospectively, in 36 of 79 subjects at risk for pheochromocytoma (46 percent), 42 unsuspected pheochromocytomas were found. Overall, there were 130 patients with 185 pheochromocytomas; 43 had von Hippel-Lindau disease, 24 had MEN-2, and 63 had sporadic tumors. The patients with familial and those with sporadic pheochromocytomas differed in mean age at diagnosis (32 vs. 46 years, P < 0.001), multifocal localization (55 vs. 8 percent, P < 0.001), and cancer (0 vs. 11 percent, P = 0.005); but not in the frequency of extraadrenal tumors (24 vs. 16 percent). Thirty-eight percent of carriers of von Hippel-Lindau disease and 24 percent of carriers of MEN-2 had pheochromocytoma as the only manifestation of their syndrome.

CONCLUSIONS

All patients with pheochromocytomas should be screened for MEN-2 and von Hippel-Lindau disease to avert further morbidity and mortality in the patients and their families. All patients in families with MEN-2 or von Hippel-Lindau disease should be screened for pheochromocytoma, even if they are asymptomatic.

[Nuclear spin tomographic findings in compensated chronic hemolysis. A case report of a hereditary spherocytosis]

A case report of a 58-year-old patient with hereditary spherocytosis and large paravertebral masses in the thorax and abdomen is presented MRI detects the origin of the masses with typical signal intensities of the masses and the bone marrow in T1 and T2 weighted sequences as extramedullary hematopoiesis. In this special case there is bleeding into these masses and, as often, liver hemosiderosis and splenomegaly.

[Metal abrasion as an imaging artefact in nuclear spin tomography]

Eighteen patients with vertebral body fractures that had been stabilized by an internal spinal skeletal fixation system were prospectively examined by magnetic resonance (MR) imaging between February 1989 and November 1990 at the Department od Diagnostic Radiology of the University Hospital Freiburg 3-7 days after removal of the metallic implants. In most cases imaging artifacts in the paraspinal extensor muscles were evident on MR studies. These were found especially in the region of the previous site of the metal clip jaw bearing. In a few cases artifacts were also present within the vertebral body and/or vertebral arch, but only if the vertebral body had been surgically reconstructed by transpedicular spongiosa implantation. None or only minor artifacts by abrasion of metal were detected if the (modified Schanz's) screws appeared to be tight at surgical removal of the implants. Therefore, marked metal artifacts on MR imaging retrospectively indicate a chronic straining of the implants, which has been shown to be a risk factor for implant loosening. Additional in vitro studies with powdered metallic alloy showed that as little as 1 mg of metal could be detected as artifacts in routine spin-echo sequences. When the metallic pieces were large enough to be seen on conventional radiographs or computed tomograms, they caused severe, distorting artifacts on MR imaging. It is concluded that MR imaging is the method of choice for detection of small amounts of metal.

Correlation of ultrasound and renal scintigraphy in children with unilateral hydronephrosis in primary workup

Ultrasound accurately detects hydronephrosis in infants and children, while nuclear medicine techniques quantify relative renal function in addition to characterizing the urodynamic relevance of hydronephrosis. This prospective study was undertaken to examine the relationship between ultrasound morphological findings and relative renal function, quantified with dynamic 99mtechnetium mercaptotriacetylglycine imaging, in the initial diagnostic workup of children with unilateral hydronephrosis. The ultrasound grade of hydronephrosis and relative renal function ipsilateral to the hydronephrosis were inversely related, indicating that with more severe hydronephrosis ultrasound fails to estimate the potential reduction of relative kidney function. Because renal function is not necessarily affected by hydronephrosis, renal scintigraphy is indicated to assess the functional status of hydronephrotic kidneys.

[Magnetic resonance tomography of so-called transient osteoporosis. Primary diagnosis and follow-up after treatment]

Transient osteoporosis or transient bone marrow oedema is a rare cause of acute hip pain that predominantly affects adults of middle and younger age. We report on the MR image in 8 patients with transient bone marrow oedema of the hip and in one patient with affection of the knee joint. In three of these, sympathetic nerve blockade has been performed. The MR image after sympathicolysis is discussed.

[Pheochromocytoma as dominant manifestation of v. Hippel-Lindau syndrome]

A diagnosis of von Hippel-Lindau syndrome was made in two families originating from the same part of the Black Forest but apparently unrelated. Nine affected persons (seven males and two females) had a total of 17 tumours: retinal angioma (4), haemangioblastoma of the CNS (1), and phaeochromocytoma (12). Three of the affected persons and eight of the tumours (six phaeochromocytomas, two retinal angiomas) were diagnosed by family screening. Phaeochromocytoma was diagnosed in eight persons; in four it was the only symptomatic lesion. After extensive diagnostic tests the phaeochromocytoma was the sole tumour in four. Despite severe symptoms the diagnosis of von Hippel-Lindau syndrome had not been made prior to the screening examinations because either the common aetiology of the tumour was not known or there was insufficient exchange of information between the two families.--It is recommended that in each case of phaeochromocytoma von Hippel-Lindau syndrome should be excluded so that lesions can be discovered early in other organs and in other affected family members. If the syndrome is present, annual examinations are indicated because of asynchronous and multi-focal tumour growth.

MR imaging of the pericardial cyst

Findings obtained with magnetic resonance (MR) imaging in four patients with pericardial cyst are reported. MR imaging allowed not only localization and diagnosis in all four cases but characterization of cystic content. MR imaging, including RARE (rapid acquisition with relaxation enhancement) MR hydrography, which shows only liquids with T2s greater than 500 msec, proved to be useful in characterizing the fluid content of a mediastinal lesion and monitoring follow-up. In one case, MR imaging allowed differentiation of a pericardial cyst from a suspected necrotic lymph node in a patient with colic carcinoma, with subsequent correction of staging and therapy. The authors conclude that MR imaging is the method of choice for diagnosis (especially in unusual locations) and monitoring of pericardial cysts and for differential diagnosis of malignant mediastinal cystic tumors that show a solid part.

[Indications for magnetic resonance tomography of abdominal space-occupying lesions in children]

The frequency of magnetic resonance imaging for investigation of abdominal tumors in childhood is increasing. Malignancies of the liver can be visualized. For benign lesions the accuracy is high particularly in the case of hemangiomas. Magnetic resonance investigations are advisable in the presence of abdominal tumors, in order to differentiate lymph nodes and vascular involvement. Magnetic resonance imaging is mandatory in the case of retroperitoneal and presacral masses to depict any intraspinal tumor spread. RARE myelography can replace computed tomography myelography.

[Obstetric pelvimetry using nuclear magnetic resonance tomography (MRI): clinical experiences with 150 patients]

Between Oct. 1987 and Oct. 1991 150 patients of the Frauenklinik Freiburg were examined by MR pelvimetry (MRI), 135 of which were "ante partum", i.e. just before delivery. The indications were: earlier operative or strongly protracted delivery, clinical suspicion of disproportion between head and pelvis, or obstetrical "problem pelvis" indicated by manual pelvic examination or ultrasonic foetometry. Previous experimental measurements with a phantom and the comparison with conventional radiograms by Guthmann and Martius of 10 patients in puerperium have shown, that the mean divergence was +/- 2 mm, the maximum divergence 5 mm. The MRI method for pelvimetry "ante partum" or in childbed, proved to be a method of high accuracy and a very good option to judge the pelvic shape, whilst being well accepted by the patients. Furthermore, it allows to determine the foetal BIP (biparietal head-diameter), to judge the pelvic soft-tissue, as well as the visualisation of the birth canal, all without any exposure to radiation. MR pelvimetry is thus part of today's clinical routine. The disadvantages are still the high costs as well as the fact, that only few centres have access to MRI equipment. Nevertheless, the pelvimetry "post partum" can be safely practised radiologically due to the very low radiation exposure.

MRI of knee arthritis in rheumatoid arthritis and spondylarthropathies

The knees of fifty-two patients suffering from rheumatoid arthritis (RA), 22 patients with seronegative spondylarthopathies (SA) as well as of 20 healthy volunteers were examined by magnetic resonance imaging (MRI). Osseous erosions (RA 52%-SA 18%; P less than 0.005), Baker cysts (RA 56%-SA 12%; P less than 0.005), pannus formation (RA 67%-SA 36%; P less than 0.05), and cartilage thinning with narrowing of the joint space (RA 46%-SA 18%; P less than 0.05) proved to be more frequent MRI findings in patients with RA. Additionally, in patients with RA erosions were more extensive. Follow-up MRI examinations of 19 patients revealed an improvement in MRI changes in SA within an average interval of 6 months. No substantial changes were noted in 7 of 13 RA patients. Quantitative and qualitative MRI findings of knee arthritis differ in patients with RA and SA and this was statistically significant. However, as there is considerable overlap of the MRI and radiographic changes in both groups the discriminating diagnostic value in the individual case was limited.

[MR imaging of a giant solitary trichoepithelioma of the skin]

Magnetic resonance images of a "giant solitary trichoepithelioma" (GST) are presented for the first time. Furthermore, to our knowledge this is the largest GST ever to be reported in the current literature. Magnetic resonance imaging gave information on the origin of the tumor and on the depth of invasion. The signal intensity is non-specific and does not allow histological classification. Preoperatively, the MR examination depicts the extent of the tumor and thus helps in the surgical management that follows.

[MR tomography of aneurysmal bone cyst]

The preoperative findings of magnetic resonance imaging (MRI) in six histology-proven aneurysmal bone cysts (ABC) are examined and compared with previous publications concerning MRI of ABC. The signal intensities differ considerably, and not all of our cases conform with the literature data. They can be summarised in three different subheadings: one form that is very inhomogeneous in T1- and T2-weighting, with fluid-fluid levels in the cystic spaces; one intermediate form without fluid-fluid levels, which is inhomogeneous only in T2-weighted images; and finally, an unusual form of ABC that has homogeneous low signal both in T1- and T2-weighting, and which has not been described in literature so far.

Pancreatic lesions in the von Hippel-Lindau syndrome

Common manifestations of the von Hippel-Lindau syndrome, an autosomally dominant inherited cancer-prone disorder, include retinal angiomatosis, hemangioblastoma of the central nervous system, renal cysts, renal cancer, pheochromocytoma, and epididymal cystadenoma. Multiple cysts and microcystic (serous) cystadenomas of the pancreas have also been reported occasionally in patients afflicted with this syndrome. In the large Freiburg study of the von Hippel-Lindau syndrome composed of 66 affected individuals, pancreatic lesions were systematically studied. Fifty-five living individuals were examined by abdominal ultrasound imaging. Abnormal findings were confirmed by computed tomographic scan and/or magnetic resonance imaging. For an additional 11 decreased patients autopsy data were available. Cystic lesions of the pancreas were found in 10 patients (15%). One of these patients presented with multiple pancreatic cysts as the only manifestation of the syndrome. In one patient, a malignant islet-cell tumor was found at autopsy. Because multiple pancreatic cysts did not cause major clinical symptoms and because follow-up examinations over an average period of 5 years did not show significant progression of the lesions, it is concluded that these patients usually do not require surgical treatment. Abdominal ultrasound screening is recommended for patients at risk as a tool to identify potential von Hippel-Lindau syndrome gene carriers with pancreatic manifestations. In all patients with multiple pancreatic cysts, the von Hippel-Lindau syndrome should be included in the differential diagnosis.

[RARE-MR urography: a rapid MR tomographic imaging procedure for the diagnosis of urinary tract malformations in childhood]

RARE-MR urography (so called "water-pictures") is a fast MR imaging technique that selectively depicts fluid without contrast application. Acquisition time is 6.4 s per slice with 1 excitation, or 23 s per slice with 2 averages respectively. From Sept. 1989 to April 1990 24 children with anomalies of the urinary tract have been examined each by RARE MR urography and one T1-weighted spin-echo sequence. Independent of excretory function, the technique can show dilated calices and renal pelvis, pelviureteric obstruction, renal duplication, and megaureter. However, it cannot distinguish between vesicoureteric reflux and obstructive megaureter. Our first results suggest that RARE MR urography combined with ultrasound, reflux cystography and isotope nephrography, can replace excretory urography in certain circumstances--or at least postpone it to the preoperative phase.

[Magnetic resonance tomography in the diagnosis of peripheral joints]

Magnetic resonance imaging (MRI) provides an excellent soft tissue contrast with high spatial resolution. Using spin echo and fast gradient echo sequences all relevant joint structures such as the hyaline cartilage, the meniscus, the ligaments, the tendons, the capsulae, and their adjacent muscles and their pathology are visualized. Diagnosis of osteonecrosis, meniscal and cruciate ligament lesions, as well as tumors, represents the major current indication for MRI. Due to its high cost MRI should be employed for the diagnosis of joint disease only to clarify equivocal findings of conventional radiographic, nuclear and tomographic methods. Prior clinical examination and laboratory tests are mandatory. As a component of a stepwise diagnostic approach, MRI often provides reliable differential diagnostic information.

[A technic of magnetic resonance tomographic pelvimetry in obstetrics]

Magnetic resonance imaging (MRL) allows for the first time direct determination of maternal pelvic dimensions without ionising radiation. Phantom measurements and the correlation with traditional pelvimetric measurements in 10 patients after Caesarean section have shown mean differences of +/- 2 mm, with a maximum of 5 mm. The evaluation of pelvic configuration is obtained analogous to the conventional roentgenogram. In addition to conventional or digital x-ray pelvimetry, the soft tissues of the maternal pelvis and the presenting part of the foetus is delineated with high contrast. Positioning in the body coil can be accomplished even late in pregnancy or in impending labour, acceptance by the pregnant women being high. Whereas in a given indication after delivery conventional x-ray pelvimetry continues to be performed, antenatally MRI pelvimetry has now been established in our Departments as the method of choice--based on meanwhile 107 examinations. Present drawbacks are the relatively high cost and the limited availability of MR units.

RARE-MR-urography in the diagnosis of upper urinary tract abnormalities in children

RARE-MR-urography (Rapid Acquisition with Relaxation Enhancement) is a fast MR imaging technique (6.4 s/acquisition) that selectively depicts fluid by heavy T2-weighting. From 9/1989 to 11/1990, RARE-MR urograms were prospectively evaluated in the diagnosis of upper urinary tract abnormalities in 55 children. The method is performed in several planes and combined with a coronal, T1-weighted spin-echo sequence. Forty out of 42 kidneys with dilated renal pelvis, and 21 out of 24 dilated ureters were identified, only the mildly dilated ones were missed. Even in non-functioning kidneys the urinary tract was clearly depicted by RARE-MR-urography. However, no differentiation could be made with this technique between vesicoureteral reflux and non-refluxing dilatation of ureter and/or renal pelvis. All 19 pelviureteric obstructions and all eight renal duplications with a dilated segment were identified. RARE-MR-urography is a new tool for diagnosing urinary tract abnormalities in children without having to employ ionizing radiation, contrast media, or general anesthesia. A dilated urinary tract can be shown in one image displaying the entire urinary system, similar to excretory urography. The technique is presently not able to provide the information of voiding cystourethrography or renal scintigraphy, nor is it as easy to perform as ultrasound. However, in certain cases it may replace excretory urography.

[Non-Hodgkin's lymphoma of the descending colon in a 6-year-old girl]

The most common site of non-Hodgkin lymphoma of the intestinal tract in children is the terminal ileum and the ileocecal region; boys are 5- to 10 times more frequently affected than girls, peak incidence is between 5 and 8 years of age. We present a 6-year-old girl with non-Hodgkin lymphoma of the descending colon.

Percutaneous sclerotherapy of idiopathic varicocele in childhood: a preliminary report

Of 31 boys 10 to 16 years old referred for treatment of a left grade II or III varicocele 28 underwent percutaneous sclerotherapy. Due to anatomical and technical obstacles sclerotherapy was not possible in 3 boys. At follow-up 1 of 16 boys (6.2 per cent) had a mild recurrence detected by Doppler sonography of the spermatic cord. Percutaneous sclerotherapy had no serious side effects, and proved to be an efficient and convenient treatment of left varicocele in childhood.

[Cyclophosphamide-induced pneumonitis]

Pneumotoxicity of cyclophosphamide is a rare complication of chemotherapy with this drug. 28 cases have so far been reported in world literature. We add one case in whom lung changes had appeared subacutely, after a single dose of cyclophosphamide, and were reversed by corticoids.

[Pulmonary reaction to radiation following mantle-field irradiation. Comparison of follow-up by conventional x-ray and by computed tomography]

A group of 36 patients who received mantle field irradiation for Hodgkin's disease (35 pts) or non-Hodgkin lymphoma (1 pt) were prospectively examined by plain film radiography and computed tomography (CT) for evaluation of the pulmonary reaction at the beginning and the end of the course of irradiation, and at 12 weeks, 17 weeks, and 37 weeks after the start of the mantle field irradiation. A total of 173 plain chest radiographs (p.a. and lateral view), and 167 CTs were reviewed. As in chest radiography, the pulmonary reaction to radiation seen in CT took a characteristic course with different distinguishable stages. The radiation-induced changes typically seen on on CT were reducible to three basic patterns of opacification, which sometimes appeared in combination, and had a characteristic spatial distribution. Comparison of the two imaging modalities suggest that CT should be used in special cases, while conventional plain film radiography of the chest, with the possibility of short-term controls, is still the mainstay of follow-up for patients with Hodgkin's disease.

Idiopathic varicoceles: feasibility of percutaneous sclerotherapy

Percutaneous retrograde venography was performed in 717 patients with a left-sided idiopathic varicocele. In 674 (94.0%), testicular (internal spermatic) vein insufficiency was proved by contrast medium reflux from the left renal vein into the testicular vein, down to the pampiniform plexus. The different venographic patterns of the testicular veins were classified into seven basic types. Five of these, comprising 624 patients, had incompetent or missing valves all along the trunk of the testicular vein. In 554 of the 624 (88.8%), sclerotherapy was performed, but such treatment was possible in only three of 50 patients with a competent orifice valve bypassed by an insufficient collateral (type IVb). In 43 of the 717 patients (6.0%), no insufficient vein could be found at all (type 0). The mean fluoroscopy time was 4.4 minutes. There were no serious complications associated with venography or sclerotherapy, and the initial recurrence rate was 9.8%. Percutaneous sclerotherapy is therefore a simple, safe, and effective treatment of testicular vein insufficiency and is suitable for almost 80% of patients with varicoceles.

Stop-type and shunt-type varicoceles: venographic findings

Forty-four patients with a left-sided idiopathic varicocele were examined with bidirectional Doppler ultrasound (US), physical examination, and percutaneous retrograde venography. On the basis of the Doppler findings, the varicoceles were classified as either stop type or shunt type. On venography, the stop-type varicoceles showed only retrograde blood flow (reflux) in the testicular (internal spermatic) vein, whereas each shunt-type varicocele showed both retrograde and orthograde (i.e., physiologic) venous blood flow: First, reflux appeared in the testicular vein, then orthograde flow occurred in the deferential vein, cremasteric vein, or both. The shunt-type varicocele therefore represented a kind of venous bypass. Thus, the existence of two hemodynamically different types of varicocele as suggested initially by Doppler US is confirmed by percutaneous retrograde venography. The shunting of venous blood appears to be a precondition for medium and large varicoceles and might have some prognostic significance for subfertility associated with varicoceles.

[Radiation planning in breast cancer. What is the depth of the internal mammary lymph nodes?]

For irradiation of the parasternal lymph nodes by high-energy electrons the target volume depth, i.e. the depth of the parasternal nodes below the skin surface, was determined by CT in 25 consecutive female patients with a sternal irradiation field. On measurement at the cranial end of the sternum, at a middle level, and at the caudal part of the sternal field, intraindividual differences were low, whereas interindividual findings differed markedly--depending on thickness of subcutaneous fatty tissue. For individual treatment planning, we recommend measuring target volume depth by CT.

[Percutaneous sclerotherapy of testicular vein insufficiency in persistent and recurrent varicocele]

Among 1217 retrograde phlebographies of left-sided idiopathic varicoceles 66 patients presented because of persistence or recurrence of varicocele, 34 of them after operation and 32 after sclerotherapy. After operation without success there was always - except for one case - a reflux passing the site of ligature. If persistence or recurrence of varicocele occurred after sclerotherapy, the testicular (internal spermatic) vein was most often found to be obliterated at the junction with the renal vein and the sonographically proven reflux went via collaterals or unidentified veins which prevented a repeat sclerotherapy. In 12 out of 32 patients after sclerotherapy a persistent main stem of the testicular vein allowed a second attempt of sclerotherapy. If sclerotherapy in patients after operation or previous sclerotherapy could be performed, it was an effective, low risk procedure on an outpatient basis just as in primary sclerotherapy of testicular vein insufficiency causing varicocele.