Cross-sectional computed tomography assessment of exophthalmos in comparison to clinical measurement via Hertel exophthalmometry.

To determine protrusion assessment via Hertel exophthalmometry in comparison to measurement on Computed Tomography (CT). Retrospective blinded comparison of exophthalmos measurements on axial CT with Hertel exophthalmometry measurements in 113 patients. Descriptive statistics, Pearson's correlation, Kruskal-Wallis and Mann-Whitney-U test were employed for analysis. Mean difference of proptosis between both eyes was 2.4 (SD ± 2.0) mm in CT and 2.2 (SD ± 2.0) mm in Hertel measurements. Proptosis of 0-2 mm was present in 69 (61.1%), and > 2 mm in 42 (38.9%) patients in Hertel measurements (CT 64 (56.6%), and 49 (43.4%) patients). Pearson's coefficient showed a correlation of 0.793 between both methods (p < 0.001). Accuracy of Hertel measurement depended significantly from the examiners' experience (< 5 (group 1), 5-15 (2) and > 25 (3) years, p = 0.042, Kruskal-Wallis analysis; p = 0.086 group 1 vs. 2, p = 0.014 group 1 vs. 3, p = 0.688 group 2 vs. 3, Mann-Whitney-U-test), reflected by levels of Pearson's coefficient (correlation of both methods 0.691 (group 1), 0.837 (2) and 0.831 (3), respectively, p = 0.01). Generally, Hertel exophthalmometry correlates well with CT measurements. Subgroup analysis confirmed a superior quality of Hertel measurements in favour of experienced examiners. Teaching of accurate Hertel exophthalmometry should be improved. Assessment of exophthalmos using standardized criteria should be implemented for imaging reports.

[Imaging procedures to diagnose prostate cancer]. / Bildgebende Verfahren bei der Diagnose des Prostatakarzinoms.

Prostate cancer is one of the most frequent malignant diseases in men. Despite constant progress achieved in imaging procedures, prostate biopsy is the gold standard for diagnosing prostate cancer. For the assessment of lymph node status, only staging lymphadenectomy provides valid information. The aim of this work is to analyze the imaging procedures available in Germany and their value in primary and lymph node staging as well as biochemical recurrence.

Magnetic resonance imaging: a useful tool to distinguish between keratocystic odontogenic tumours and odontogenic cysts.

In contrast to odontogenic cysts, keratocystic odontogenic tumours often recur and require more aggressive surgical treatment, so we tried to find features that distinguished between them on magnetic resonance imaging (MRI). Without knowing the diagnosis, two radiologists reviewed intensity (low, intermediate, or high) and homogeneity (homogeneous or heterogeneous) of signals in short-tau-inversion-recovery (STIR), T1- and T2-weighted, and fat-suppressed, contrast-enhanced MRI in 20 consecutive patients with oval, radiolucent lesions of the mandible on panoramic radiography, and who were subsequently confirmed histopathologically to have either an odontogenic cyst or a keratocystic odontogenic tumour (n=10 in each group). Fisher's exact test was statistically significant at p<0.05. Delineation of a contrast-enhanced wall of a cyst with high signal intensity distinguished odontogenic cysts (9/10 and 8/10, respectively) from keratocystic odontogenic tumours (3/10, p=0.02, and 1/10, p=0.01, respectively). One radiologist found odontogenic cysts were more likely to be homogeneous on unenhanced T1-weighted images (odontogenic cysts 9/10, keratocystic odontogenic tumours 3/10, p=0.02) and one on contrast-enhanced MRI, when the cyst wall was enhanced (odontogenic cysts 7/9, keratocystic odontogenic tumours 0/3, p=0.01). There were no other significant distinguishing features on MRI. In conclusion, the signal intensity of the enhanced wall seems to be a feature on contrast-enhanced MRI that differentiates odontogenic cysts from keratocystic odontogenic tumours.

Non-invasive temperature mapping using MRI: comparison of two methods based on chemical shift and T1-relaxation.

PURPOSE: To implement and evaluate the accuracy of non-invasive temperature mapping using MRI methods based on the chemical shift (CS) and T1 relaxation in media of various heterogeneity during focal (laser) and external thermal energy deposition. MATERIALS AND METHODS: All measurements were performed on a 1.5 T superconducting clinical scanner using the temperature dependence of the water proton chemical shift and the T1 relaxation time. Homogeneous gel and heterogeneous muscle phantoms were heated focally with a fiberoptic laser probe and externally of varying degree ex vivo by water circulating in a temperature range of 20-50 degrees C. Magnetic resonance imaging data were compared to simultaneously recorded fiberoptic temperature readings. RESULTS: Both methods provided accurate results in homogeneous media (turkey) with better accuracy for the chemical shift method (CS:+/-1.5 degrees C, T1:+/-2.0 degrees C). In gel, the accuracy with the CS method was +/-0.6 degrees C. The accuracy decreased in heterogeneous media containing fat (T1:+/-3.5 degrees C, CS: +5 degrees C). In focal heating of turkey muscle, the accuracy was within 1.5 degrees C with the T1 method. CONCLUSION: Temperature monitoring with the chemical shift provides better results in homogeneous media containing no fat. In fat tissue, the temperature calculation proved to be difficult.

[Parametrial infiltration of cervix carcinoma: diagnostic value of contrast-enhanced fat-suppressed T1-weighted SE sequences at 1.5 tesla]. / Parametrane Infiltration beim Zervixkarzinom: Diagnostische Wertigkeit von kontrastverstärkten fettsupprimierten T1-gewichteten SE-Sequenzen bei 1,5 Tesla.

PURPOSE: To determine whether contrast-enhanced and fat-suppressed sequences contribute to the MR imaging diagnosis of parametrial invasion. METHODS: 21 patients with carcinoma of the cervix were prospectively examined with a phased-array coil and a 1.5T MR-scanner using the following sequences: transverse T2-weighted turbo spin echo (T2-TSE), T1-weighted spin echo (T1-SE) and fat suppressed T1-weighted SE sequences before and after Gd-DTPA. The sequences were evaluated separately for the presence of parametrial invasion. Image quality and diagnostic confidence were classified on a scale of 0-10 (nondiagnostic-excellent). Findings were compared to the results of the pathohistological examination. RESULTS: Sensitivity, specificity and diagnostic accuracy were highest for T2-TSE sequences (100%, 79% and 86%, respectively). Contrast-enhanced T1-SE sequences with fat-suppression (71%, 79%, and 76%) showed no improvement compared to T2-TSE. Unenhanced fat-suppressed T1-SE (100%, 30%, and 56%) and unenhanced T1-SE (100%, 7%, and 38%) as well as contrast-enhanced T1-SE (86%, 20%, and 47%) were significantly worse than T2-TSE. With similar image quality (p < 0.05) diagnostic confidence was higher on T2-TSE than on any of the other sequences (p < 0.001). CONCLUSION: Considering the cost-effectiveness of the examination, for the MR diagnosis of parametrial invasion the use of fat-suppressed contrast-enhanced sequences can be abandoned in favour of T2-weighted TSE sequences.

[Lymph node staging in cervix carcinomas: the results of high-resolution magnetic resonance tomography (MRT) with a phased-array body coil]. / Lymphknotenstaging beim Zervixkarzinom: Ergebnisse der hochauflösenden Magnetresonanztomographie (MRT) mit einer Phased-Array-Körperspule.

PURPOSE: To determine the diagnostic value of high resolution MR imaging with a circularly polarised (c.p.) body phased-array coil for the staging of pelvic lymph nodes in cervical carcinoma. MATERIAL AND METHODS: 42 patients with histologically proven carcinoma of the cervix were studied on a 1.5 T scanner by using a c.p. body phased-array coil. The imaging protocol included T2-weighted turbo-spin-echo (TSE) and T1-weighted spin-echo sequences pre and post i.v. application of Gd-DTPA; slice thickness was 5-7 mm and pixel size 0.53 mm2. Lymph nodes with a diameter of > or = 8 mm were considered to have metastatic involvement. MR imaging results were compared with histopathologic findings. RESULTS: MR imaging showed enlarged lymph nodes (> or = 8 mm) in 16 of 18 patients with histologic proof of lymph node metastases (sensitivity 89%). In 22 of 24 cases MR findings were true negative (specificity 92%). Diagnostic accuracy was 91%. CONCLUSION: High-resolution MR imaging with a c.p. body phased-array coil provides high sensitivity, specificity, and diagnostic accuracy for pelvic lymph node staging in cervical carcinoma.

[The facial nerve in the petrous bone in thin-layer paratransverse and sagittal magnetic-resonance-tomographic T1-spin-echo and FLASH images]. / Der Nervus facialis im Felsenbein in dünnschichtigen paratransversalen und sagittalen magnetresonanz-tomographischen T1-Spin-Echo- und FLASH-Aufnahmen.

PURPOSE: It is difficult to effect visualization and delineation of the facial nerve and its neighbouring structures in the temporal bone with conventional MRI examination protocols. We tested temporal bone MRI with 2 mm slices and compared T1-weighted FLASH (TR = 400 ms, TE = 10 ms, 90 degrees flip angle) and spin-echo (TR = 540 ms, TE = 15 ms) sequences. PATIENT AND METHODS: 5 volunteers and 14 patients were examined with the head coil of a 1.0T whole body MRI scanner (Impact, Siemens, Erlangen) with para-transversal images orientated parallel to the inferior outline of the clivus and sagittal images orientated along the brainstem. RESULTS: The facial nerve and its neighbouring structures could be reliably visualized and differentiated along its entire course. The FLASH sequence was superior to the spin-echo sequence. 8 of 11 patients with peripheral facial nerve palsy showed contrast enhancement. In two patients, local swelling of the affected facial nerve was evident. CONCLUSION: The MRI technique tested here seems promising for temporal bone examinations.

[Technics for the preoperative marking of nonpalpable breast lesions in MRT]. / Techniken der präoperativen Markierung nicht-palpabler Mammaläsionen in der MRT.

We describe a method of localizing suspicious breast lesions only visible by MRI that does not require additional hardware and can be carried out on any MRI-scanner suited for MR-mammography. We have performed a total of 48 localizations with different techniques: 28 charcoal/Gd-DTPA, 18 with wires and two skin markings. All localizations have been successful; wire localizations provided the best results, since the position of the wire could be corrected under MR-guidance. Until suitable localization- and biopsy coils become available the methods employed by us provide a satisfactory alternative which allows radiologists who perform diagnostic MR-mammography with techniques to carry out precise pre-operative localisations of breast lesions.

High resolution Gd-DTPA MR imaging of the inner ear in 60 patients with idiopathic vestibular neuritis: no evidence for contrast enhancement of the labyrinth or vestibular nerve.

Sixty patients with acute idiopathic vestibular neuritis (confirmed by clinical examination and caloric irrigation) were evaluated in a prospective study by high resolution magnetic resonance imaging (hr-MRI) between days 3 and 30 after onset of symptoms. We used a 1.5 Tesla imager with an axial and coronal T1-weighted 2D-fast low angle shot-, T2-weighted turbo spin echo-, and an axial T2-weighted 3D-constructive interference in steady-state sequence for MRI. None of the patients' MRIs exhibited contrast enhancement of the labyrinth, vestibulocochlear nerve, or vestibular ganglion, even when high doses of gadolinium (0.2 mmol/kg) were used. In contrast, several previous studies demonstrated contrast enhancement of the vestibulocochlear nerve/labyrinth in herpes zoster oticus, labyrinthitis, and Cogan's syndrome or of the facial nerve in Bell's palsy. On the basis of our MRI findings, we speculate that idiopathic vestibular neuritis is neither a viral infection directly affecting the nerve (such as herpes zoster) nor a labyrinthitis. An autoimmunological disease of the labyrinth, which should involve only the anterior and horizontal semicircular canals, is also unlikely. A subacute reactivation of a latent viral infection--as discussed for Bell's palsy--is compatible with our MRI findings. The observed differences between contrast enhancement of the facial nerve in Bell's palsy and the vestibulocochlear nerve in vestibular neuritis may be due to their dissimilar anatomy: contrary to the vestibular nerve, the facial nerve has very prominent circumneural arteriovenous structures. Hyperemia within these vascular structures may cause the contrast enhancement seen in Bell's palsy.

[Urological emergencies]. / Urologische Notfälle.

Urological emergencies that require specialist treatment include testicular torsion, gross hematuria, urogenital injuries and acute flank pain. After initial symptoms-adapted therapy, patients should be transferred immediately to an urological department for imaging (e.g. ultrasound, IVP, CT) and further specific examinations (e.g.blood tests, urine analysis, microbiology). Acute lower abdominal and scrotal pain in young men may be symptomatic of testicular torsion, which requires immediate urological surgery. Gross hematuria is usually not a life-threatening emergency. Nevertheless, urogenital tumor has to be ruled out by an urologist. Patients with urogenital injuries are triaged into surgical and non-surgical treatments. Differential diagnosis of acute flank pain falls into several medical fields. After initial symptom-related therapy, further diagnostic procedures have to be performed. Septic presentation may be symptomatic of infectious hydronephrosis which requires immediate urological intervention.

[Partial priapism. Case report and review of the literature of diagnostic and therapeutic measures]. / Partieller Priapismus. Kasuistik und Literaturübersicht über diagnostisches und therapeutisches Vorgehen.

Partial priapism is a rare condition which has been previously reported in the literature only in eight cases. Unlike the typical case of priapism, patial priapism generally shows erection only of the proximal corpora cavernosa. In most of the cases a well defined membrane separated the proximal erected and the distal flaccid part of the corpus. The origin of the fibrous membrane is not clear. Usually a painful segmental thrombosis of the corpora cavernosa was found proximal the membrane. Until 1985 diagnosis and therapy of this entity have principially involved invasiv methods. Later computed tomography (CT) and magnetic resonance (MR) were used for noninvasive imaging and conservative management was elected. We report a case of partial priapism and review the diagnostic and therapeutic procedure in the previous literature.

[Aerobilia as an initial sign of a cholecystoduodenal fistula--a case report]. / Patientin mit langjähriger Cholezystolithiasis. Woran denken Sie bei Aerobilie?

An 82 year old female patient has the following medical history: repeated chemotherapy and radiation therapy for non-Hodgkin's lymphoma, a radiation-induced osteoblastic osteosarcoma and a longstanding cholecystolithiasis with sclero-atrophic cholecystitis. She appeared at the practice and complained about a dull food-dependent mesogastric and epigastric pain as well as a discrete scleral jaundice. Sonography and CT showed air inclusions in the bile ducts. Subsequently, a cholecystoduodenal fistula was found intraoperatively. The cause could be the long-existing cholecystolithiasis.

Extramedullary multiple myeloma presenting as a pituitary mass lesion.

INTRODUCTION: A plasmocytoma involving the pituitary gland is an extremely rare entity, with approximately 22 cases of solitary myeloma or multiple myeloma presenting with sellar mass reported in the literature so far. CASE REPORT: Here, we report the case of a 71-year-old female patient affected by an extramedullary IgG-lambda multiple myeloma presenting as a pituitary mass lesion. We summarize the diagnostic approaches that confirmed the diagnosis of multiple myeloma and describe treatment outcome after therapy. DISCUSSION: Intrasellar plasmocytoma though rare, should be considered in the differential diagnosis of a pituitary mass lesion, since associated with different therapeutic and prognostic implications. Physicians should be alert for intrasellar plasma cell tumors in case of well preserved anterior pituitary function in combination with cranial nerve neuropathies and sellar destruction.

MR-perfusion (MRP) and diffusion-weighted imaging (DWI) in prostate cancer: quantitative and model-based gadobenate dimeglumine MRP parameters in detection of prostate cancer.

BACKGROUND: Various MR methods, including MR-spectroscopy (MRS), dynamic, contrast-enhanced MRI (DCE-MRI), and diffusion-weighted imaging (DWI) have been applied to improve test quality of standard MRI of the prostate. PURPOSE: To determine if quantitative, model-based MR-perfusion (MRP) with gadobenate dimeglumine (Gd-BOPTA) discriminates between prostate cancer, benign tissue, and transitional zone (TZ) tissue. MATERIAL AND METHODS: 27 patients (age, 65±4 years; PSA 11.0±6.1 ng/ml) with clinical suspicion of prostate cancer underwent standard MRI, 3D MR-spectroscopy (MRS), and MRP with Gd-BOPTA. Based on results of combined MRI/MRS and subsequent guided prostate biopsy alone (17/27), biopsy and radical prostatectomy (9/27), or sufficient negative follow-up (7/27), maps of model-free, deconvolution-based mean transit time (dMTT) were generated for 29 benign regions (bROIs), 14 cancer regions (cROIs), and 18 regions of transitional zone (tzROIs). Applying a 2-compartment exchange model, quantitative perfusion analysis was performed including as parameters: plasma flow (PF), plasma volume (PV), plasma mean transit time (PMTT), extraction flow (EFL), extraction fraction (EFR), interstitial volume (IV) and interstitial mean transit time (IMTT). Two-sided T-tests (significance level p<0.05) discriminated bROIs vs. cROIs and cROIs vs. tzROIs, respectively. RESULTS: PMTT discriminated best between bROIs (11.8±3.0 s) and cROIs (24.3±9.6 s) (p<0.0001), while PF, PV, PS, EFR, IV, IMTT also differed significantly (p 0.00002-0.0136). Discrimination between cROIs and tzROIs was insignificant for all parameters except PV (14.3±2.5 ml vs. 17.6±2.6 ml, p<0.05). CONCLUSIONS: Besides MRI, MRS and DWI quantitative, 2-compartment MRP with Gd-BOPTA discriminates between prostate cancer and benign tissue with several parameters. However, distinction of prostate cancer and TZ does not appear to be reliable.

[Alternative sonographic determination of liver size by intercostal scans]. / Alternative sonographische Bestimmung der Lebergrösse durch interkostale Schnittführung.

BACKGROUND: The evaluation of hepatic size is a daily question in abdominal ultrasound, especially to determine the presence of hepatomegaly. In the literature, different methods of measurement are described, mostly as a subcostal measured organ diameter in one direction. This method has its limits in patients with obesity, accumulation of abdominal gas or in uncooperative patients (lack of coordinative respiration) so that alternative measurements are necessary. METHODS: In 241 patients hepatic size was first measured in two conventional sections: midclavicular line (MCL) and anterior axillary line (AAL). Additionally, we measured the organs in midaxillary line craniocaudal (MAL) by determination of the cranio-caudal diameter. In 58 patients additional computed tomography was performed due to special diagnostical reasons so that liver size in MCL could be revealed and compared with ultrasonographical values. RESULTS: The mean value in MCL was 10.7 +/- 2.1 cm measured by ultrasound, 11.4 +/- 3.7 cm measured by computed tomography, 14.0 +/- 1.9 cm in AAL and 14.9 +/- 2.0 cm in MAL. In 5% of the cases the liver could not be measured in the conventional subcostal sections due to obesity or masking by gas, but this was possible in MAL. CONCLUSIONS: We revealed a good correlation of liver size in MCL between ultrasound and computed tomography, as well as in the measurement of AAL and MAL diameters. However, even in cases with difficult subcostal approach intercostal diameters allow for an accurate determination of hepatic size.

[Urological diagnosis of prostate carcinoma]. / Urologische Diagnostik des Prostatakarzinoms.

PURPOSE: To summarize current urologic measures in the diagnosis of prostate cancer. MATERIAL AND METHODS: Current urologic literature as listed by electronic literature search and retrieval media (PubMed, Medline) was evaluated. Current measures and trends in the diagnosis of prostate cancer were summarized. RESULTS: Early diagnosis of prostate cancer (PCA) is crucial because PCA can be curatively treated only in its early stages. German general health insurance covers digital rectal examination (DRE) in men over the age of 45, however measurement of prostate specific antigen-serum levels (PSA) as a screening measure for PCA is not covered. CONCLUSION: DRE, PSA-serum level measurements, transrectal ultrasound and prostate biopsy are essential in the early diagnosis of PCA.

[High resolution magnetic resonance tomography of the temporal bone]. / Hochauflösende Kernspintomographie am Felsenbein.

Computed tomography (CT) has long been the method of choice for investigations of the temporal bone. Advances in high resolution magnetic resonance imaging (MRI) enabled MRI of the temporal bone. The purpose of this study was to assess detailed reconstruction of the anatomy of the temporal bone by MRI. Healthy volunteers were examined on a 1T MR whole body scanner (Impact, Siemens, Erlangen, Germany). A Helmholtz-configurated head coil was used. A T1-weighted 2D-FLASH sequence (TR = 400 ms, TE = 10 ms, 90 degrees flip angle, 2 mm slice thickness, 180* 256 matrix, 160 mm FOV) was performed pre- and postcontrast as well as a T2-weighted turbo spin echo sequence (TR = 6300 ms, TE = 112 ms, 3 mm slice thickness, 200 mm matrix, 200 mm FOV). A sagittal and an angulated paraxial projection, parallel to the nasopharyngeal edge of the clivus, were chosen. We suceeded in imaging the facial nerve along its entire course, including the geniculate ganglion and the greater superficial petrosal nerve, the cochlear nerve and the vestibular nerve (superior and inferior part). The facial nerve was visualised continuously from the cerebellopontine angle to the foramen stylomastoideum. The delineation of the different turns of the cochlea, the vestibule and the semicircular canals was excellent. High resolution MRI promises to be of great value in the diagnosis of the temporal bone.

[MR imaging of prostate cancer]. / MR-Tomographie des Prostatakarzinoms.

PURPOSE: Accurate diagnosis and staging of prostate cancer (PC) is developing into an important health care issue in light of the high incidence of PC and the improvements in stage-adapted therapy. The purpose of this paper is to provide an overview on the current role of MR imaging and MR spectroscopy in the diagnosis and staging of PC. MATERIAL AND METHODS: Pertinent literature was searched and evaluated to collect information on current clinical indications, study techniques, diagnostic value, and limitations of magnetic resonance imaging and spectroscopy. RESULTS: Major indications for MR imaging of patients with suspected PC are to define tumor location before biopsy when clinical or TRUS findings are inconclusive, and to provide accurate staging of histologically proven PC to ascertain effective therapy. Current MR imaging techniques for the evaluation of PC include multiplanar high-resolution T2-weighted FSE and T1-weighted SE sequences using combined endorectal and phased-array coils. Using these techniques, the reported accuracy of MR imaging for the diagnosis of extracapsular tumor extension ranges between 82 and 88% with sensitivities between 80 and 95%, and specificities between 82 and 93%. Typical MR findings of PC in different stages of disease, as well as diagnostic problems, such as chronic prostatitis, biopsy-related hemorrhage and therapy-related changes of prostatic tissue are discussed. In addition, the current perspectives and limitations of MR spectroscopy in PC are summarized. CONCLUSIONS: Current MR imaging techniques provide important diagnostic information in the pretherapeutic workup of PC including a high staging accuracy, and is superior to TRUS.

[Ultrasonography of veins]. / Ultraschalluntersuchungen der Venen.

PURPOSE: The high incidence of acute and chronic diseases of the venous system requires the application of reliable, non-invasive, low-cost methods in diagnosis and follow-up after therapy. MATERIAL AND METHODS: Current technology, principles of examination, and results of ultrasonography of the peripheral venous systems are reviewed. RESULTS: Since the mid 1980s, compression ultrasonography (US) has been introduced in the diagnosis of deep venous thrombosis. Doppler-US methods reach the hallmarks of venous imaging, particularly since the advent of color duplex US. In thrombosis, postthrombotic syndrome, and primary varicosis, color duplex US increasingly replaces the "gold standard" of phlebography as the imaging method of choice. Venous diseases of the neck, and of the upper and lower extremities are reliably recognized by color duplex US. New areas of application of Doppler and duplex-US include examinations of the venous system in patients in intensive care units, evaluation of transplanted organs, and the demonstration of blood flow in hemodialysis shunts. CONCLUSIONS: Color duplex US is useful in most imaging investigations of the peripheral veins. In view of cost development in the medical imaging sector, however, in which ultrasonography takes a major part, critical indication for the application of Doppler- and duplex-US in the diagnosis and follow-up of venous disease is out most importance.