[Mammography screening. Concept, quality assurance and interdisciplinary cooperation]

In 2005/2006 the German National Mammography Screening Program was initiated and has now become established. The objective is to reduce breast cancer mortality and the early diagnosis and therapy of small cancers. The program follows the European guidelines and is controlled by over 30 parameters of quality. All trained members of the team document each step of the screening chain electronically. Histological assessment (HA) is recommended in up to 2% of examinations, 90% of HAs are performed by core needle biopsy (CNB) or by stereotactic vacuum-assisted biopsy (VABB). Open diagnostic biopsies are performed in <10% of all HAs and therapy is successful in some of the B3 lesions. Mammograms are interpreted by two independent readers. Recommendations of the regular interdisciplinary conferences, preoperative and postoperative, follow the European guidelines. About 45% of all breast cancers detected by screening are in-situ or less than 10 mm in size. The 17% alterations diagnosed by needle biopsy are B3 or B4 lesions and impose high demands on the pathologists and the interdisciplinary team. Due to the many early and discrete lesions counterchecking of representative biopsies is crucial. Problems may be caused by sampling error or partial volume effects. Interdisciplinary conferences and knowledge of the limitations of each discipline and method are needed to optimize diagnostic and therapeutic decisions.

[Experiences of the Bavarian mammography screening program]

The Bavarian Mammography Screening Program started in April 2003. A detailed analysis of the consistency of diagnosis in the evaluation of vacuum-assisted stereotactic or core needle breast biopsies is presented. A total of 32 pathologists participated in a blinded evaluation of the biopsies. Each case was evaluated independently by two participating pathologists. A total of 1,357 cases were reviewed. The histopathological reports of the biopsies made by the two consulting pathologists were compared. The concordance rate of the first and second consulting pathologist was 93% for the B-classification. In general, the level of diagnostic agreement was very high for well defined, benign and malignant lesions. Some of the discrepancies resulted from the incorrect application of the B-classification. Discrepancies in the reports were also due to divergent interpretation of benign and "borderline" lesions. The protocol for the blinded evaluation of breast biopsies in two rounds assured a high level of quality. In conclusion, prerequisites for the success of a mammography screening program are interdisciplinary consensus conferences and audit rounds involving pathologists.

MR-guided intervention in women with a family history of breast cancer

OBJECTIVE

A study was undertaken to assess the clinical value of magnetic resonance (MR) imaging-guided interventions in women with a family history, but no personal history of breast cancer.

METHODS AND PATIENTS

Retrospective review was performed on 63 consecutive women who had a family history, but no personal history of breast cancer. A total of 97 lesions were referred for an MR-guided intervention. Standardized MR examinations (1.0 T, T1-weighted 3D FLASH, 0.15 mmolGd-DTPA/kg body weight, prone position) were performed using a dedicated system which allows vacuum assisted breast biopsy or wire localization.

RESULTS

Histologic findings in 87 procedures revealed 9 (10%) invasive carcinomas, 12 (14%) ductal carcinomas in situ, 2 atypical ductal hyperplasias (2.5%) and 2 atypical lobular hyperplasias (2.5%). Sixty-two (71%) benign histologic results are verified by an MR-guided intervention, retrospective correlation of imaging and histology and by subsequent follow-up. In ten lesions the indication dropped since the enhancing lesion was no longer visible. Absent enhancement was confirmed by short-term re-imaging of the noncompressed breast and by follow-up.

CONCLUSION

Malignancy was found in 24%, high-risk lesions in 5% of successfully performed MR-guided biopsy procedures. A 57% of MR-detected malignancies were ductal carcinoma in situ. In 10% of the lesions the intervention was not performed, since no enhancing lesion could be reproduced at the date of anticipated intervention. Such problems may be avoided if the initial MRI is performed in the appropriate phase of the menstrual cycle and without hormonal replacement therapy.

Clipmarkierung nach MRT-gesteuerter Vakuumbiopsie der Mamma

PURPOSE

The purpose of our study was to determine the placement accuracy, usefulness as a guide for wire localization, and long-term stability of tissue marker clips following MR-guided vacuum-assisted biopsy (VB) of breast lesions.

METHODS

During a 2-year period, MR-guided VB with an 11-gauge device was performed in 79 lesions. In 26 lesions a marker clip was placed at the biopsy site.

RESULTS

In 18 cases, the clip was shown to be closely adjacent to the lesion on post-interventional MR images. In seven cases in which minor bleeding occurred, the clip dislocated (< or =15 mm) in the direction of the needle pathway. In one case dislocation in the dorsal direction (< or =5 mm) was observed. In eight cases with a malignant or borderline histology according to the VB, the marker clips served as targets for mammographically guided wire localization. In all of those patients, histology results derived from open surgery confirmed those of VB. Eighteen patients with benign findings according to the VB were followed up 6 months later. Among these cases we found a significant displacement of the marker clip in one case (3 cm). The clip generally caused a round artifact (diameter of 9+/-2 mm). In two cases it was not possible to determine whether the lesion had been removed completely or was just behind the artifact caused by the clip.

CONCLUSION

Based on our results, clip marker placement following MR-guided vacuum biopsy should be called into question due to the possibility of masking the lesion by a metallic artifact and because of possible dislocation.

Success of sentinel lymph node mapping after breast cancer ablation with focused microwave phased array thermotherapy

BACKGROUND

Breast cancer tumor ablation as part of a multimodality approach in the treatment of breast cancer is the subject of recent interest. This study was conducted to determine if the ability to perform sentinel node biopsy was impaired after thermal-induced ablation of breast cancer.

METHODS

We studied patients who had sentinel node biopsy after preoperative focused microwave phased array for breast cancer ablation.

RESULTS

Twenty-one patients with T1-T2 breast cancer and clinically negative axilla underwent wide local excision and sentinel node biopsy guided by blue dye and sulfur colloid. Surgery was done an average of 17 days after microwave ablation. Fifteen of 22 patients (68%) had histologic evidence of tumor necrosis. Sentinel lymph node mapping was successful in 19 of 21 patients (91%). Axillary metastases were detected in 42% of cases.

CONCLUSIONS

This study documents successful sentinel lymph node mapping for patients treated with antecedent local tumor ablation using focused microwave phased array ablation.

Interdisciplinary consensus on the use and technique of vacuum-assisted stereotactic breast biopsy

PURPOSE

Quality assurance of stereotactic vacuum-assisted breast biopsy (VB).

METHOD

A consensus was achieved based on the existing literature and the experience of VB users (Ethicon Endosurgery, Norderstedt).

RESULTS

The imaging work-up must be completed according to existing standards before an indication for stereotactic VB is established. Indications include microcalcifications and small non-palpable masses; for the time being lesions very close to the skin and architectural distortions (radial scar) are considered less suitable. Acquisition of >20 cores (11 Gauge) should be routinely attempted (goals: as complete a removal of small lesions as possible, thereby increasing diagnostic confidence and reducing so-called 'underestimates'). The pre/post-fire and post-biopsy stereotactic images and a post-biopsy orthogonal mammogram must be documented. All cases with no or uncertain histopathological correlation require discussion in a regular interdisciplinary conference and a documented consensus concerning further work-up or therapy. Standardised documentation of the primary findings and follow-up mammography after approximately 6 months is requested.

CONCLUSION

This consensus includes protocols for the establishment of an indication, performance indicators, interdisciplinary interpretation and therapeutic recommendation, documentation and follow-up. It does not replace official recommendations for percutaneous biopsy.

Follow-up of breast lesions detected by MRI not biopsied due to absent enhancement of contrast medium

Our objective was to follow-up patients in whom scheduled MR-guided vacuum biopsies for suspicious lesions were aborted due to absent enhancement of contrast medium. Thirty-seven of 291 scheduled MR-guided vacuum biopsies were aborted. Six cases were lost to follow-up. Two could be unequivocally identified and were nevertheless biopsied. In 25 of 29 patients absent enhancement was confirmed on subsequent studies without compression. Varying hormonal or inflammatory changes between initial MRI and MR-guided vacuum biopsy most probably explain the findings. Enhancement re-appeared on short-term follow-up <6 months without compression in 4 of the 29 patients. Too strong compression during MR-guided vacuum biopsy explains the absence of enhancement in these patients. Of note, on histology, three of these cases proved malignant. We conclude that short-term follow-up without compression is necessary and recommended for all lesions not visible during scheduled MR-guided vacuum biopsy.

European quadricentric evaluation of a breast MR biopsy and localization device: technical improvements based on phase-I evaluation

Our purpose was to report about technical success, problems and solutions, as experienced in a first multicentre study on MR-guided localisation or vacuum biopsy of breast lesions. The study was carried out at four European sites using a dedicated prototype breast biopsy device. Experiences with 49 scheduled localisation procedures and 188 vacuum biopsies are reported. Apart from 35 dropped indications, one localisation procedure and 9 vacuum biopsies were not possible (3 times space problems due to obesity, 2 times too strong compression, 3 times impaired access from medially, 2 times impaired access due to a metal bar). Problems due to too strong compression were recognised by repeat MR without compression. During the procedure problems leading to an uncertain result occurred in eight vacuum biopsies, two related to the procedure: one limited access, and one strong post-biopsy enhancement. Improvements after phase-I study concerned removal of the metal bar, development of an improved medial access, of a profile imitating the biopsy gun, optimisation of compression plates and improved software support. The partners agreed that the improvements answered all important technical problems.

Multicenter study for the evaluation of a dedicated biopsy device for MR-guided vacuum biopsy of the breast

The purpose of this multicenter study was to determine the accuracy and clinical value of a dedicated breast biopsy system which allows for MR-guided vacuum biopsy (VB) of contrast-enhancing lesions. In five European centers, MR-guided 11-gauge VB was performed on 341 lesions. In 7 cases VB was unsuccessful. This was immediately realized on postinterventional images or direct follow-up combined with histopathology-imaging correlation; thus, a false-negative diagnosis was avoided. Histology of 334 successful biopsies yielded 84 (25%) malignancies, 17 (5%) atypical ductal hyperplasias, and 233 (70%) benign entities. Verification of malignant or borderline lesions included reexcision of the biopsy cavity. Benign histologic biopsy results were verified by retrospective correlation with the pre- and postinterventional MRI and by subsequent follow-up. Our results indicate that MR-guided VB, in combination with the dedicated biopsy coil, offers the possibility to accurately diagnose even very small lesions that can only be visualized or localized by MRI.

[Do tissue marker clips after sonographically or stereotactically guided breast biopsy improve follow-up of small breast lesions and localisation of breast cancer after chemotherapy?]

PURPOSE

We wanted to determine if tissue marker clips after sonographically or stereotactically guided breast biopsy improve the follow-up of small breast lesions classified BI-RADS 4/5 and the localisation of breast cancer (TNM stage 2 or 3) after neoadjuvant chemotherapy.

MATERIAL AND METHODS

Prospective analysis was performed of 108 breast lesions 1 cm or smaller mammographically classified as BI-RADS 4/5 and 14 breast lesions larger than 2 cm mammographically classified as BI-RADS 5. 33 of the 108 breast lesions 1 cm or smaller underwent sonographic core cut breast biopsy (group 1) and 75 stereotactic vacuum-assisted breast biopsy (group 2). All 14 lesions greater than 2 cm were stereotactically vacuum-assisted breast biopsied (group 3). The centre of the lesion was marked by a clip after the biopsy. Mammographies were performed in all patients of group 1 and 2 with a histologically benign finding (n = 31, n = 69, respectively) and in all patients of group 3 directly after clip placement and after 6 and 12 months. Clip localisation and possible divergence from the original position were verified by a grid.

RESULTS

Two patients of group 1 and 6 patients of group 2 had breast conservative surgery (BET) because of the histological diagnosis of a ductal carcinoma in situ or invasive breast cancer. The tissue marker clips of the remaining 31 patients of group 1 and 69 patients of group 2 diverged with a mean value of 0.4 cm (standard deviation +/- 0.23 cm; range 0.1 cm to 0.9 cm) from their placement position after 6 months. After 12 months the marker clips deviated with a mean value of 0.4 cm (standard deviation +/- 0.21 cm; range 0.1 cm to 0.9 cm) in 94 patients and 0.8 cm (standard deviation +/- 0.25 cm; range 0.1 cm to 0.9 cm) in 6 patients from their original location. No tumour progression of the benign lesions in group 1 and 2 was diagnosed in follow-up mammograms. In all patients of group 3 the tissue marker clips were the only possibility to localize the tumour after neoadjuvant chemotherapy as all other diagnostic methods showed inconsistent results.

CONCLUSION

Positioning a tissue marker clip in the tumour centre seems to be reasonable after interventional biopsy of breast lesions of 1.0 cm or smaller and before neoadjuvant chemotherapy.

MR-guided interventional breast procedures considering vacuum biopsy in particular

Histologic work-up of just MR-detected breast lesions has become essential with increasing use of contrast-enhanced MR imaging. In the present article an overview is given about the different MR-guided breast interventions, performed since 1990. Presently, for reasons of costs and image quality closed magnets are most widely used. The following approaches have been described: MR-guided freehand localization in supine position, stereotaxic localization in supine position and most frequently used localization in the prone position by means of a compression device that immobilises the breast to prevent tissue shift during intervention. Only limited experience exists with interventions on open magnets. MR-guided wire localization is a well-established procedure. Recently, percutaneous vacuum biopsy of enhancing breast lesions has become possible under MR guidance. The new system allows accurate and safe access to lesions in any location of the breast and direct check-up of representative excision by visualisation of the cavity. Thus reliable histologic evaluation of lesions smaller than 10 mm is possible with this approach.

Stereotactic breast biopsies: analysis of needle deviation based on stereotactic views

Stereotaxy is widely used for breast biopsy and needle localization of mammographically detected lesions. If a lesion shift occurs during stereotaxy, corrections (even though possible with vacuum biopsy) is difficult due to the difficult assessment of the exact 3D shift. In this study we investigated the correlation between lesion shift (in up to three dimensions) and its visualisation on the stereotactic images (0 degree, -15 degrees, +15 degrees). The study was performed on a Fischer prone table (Fischer Imaging Europe, Vejle, Denmark) using a 3.8-mm steel ball (as lesion) and a 20-G needle. The 17 major malpositions of the ball with respect to the needle were imitated and imaged. A simple rule is suggested as to how the deviation in all three dimensions can be detected from the scout and the two stereotactic views. The rule proved to be a valuable tool to correctly assess lesion shifts.

CT-guided obturator nerve block for diagnosis and treatment of painful conditions of the hip

Obturator nerve blocks (ONB) have been performed by anaesthesiologists mainly to eliminate the obturator reflex during transurethral resections. An effect on hip pain has also been described. However, being a time-consuming and operator-dependent procedure if performed manually, it has not been widely used for chronic hip pain. The purpose of this pilot study was to check whether CT guidance could improve reproducibility of the block (= immediate effect) and to test its potential value for treatment of chronic hip pain. Fifteen chronically ill patients with osteoarthritis underwent a single ONB. Sixteen millilitres of Lidocaine 1% mixed with 2 ml Iopramide was injected into the obturator canal. The patients were followed up to 9 months after the intervention. With a single injection pain relief was achieved for 1-8 weeks in 7 of 15 patients. Excellent pain relief for 3-11 months was achieved in another 4 patients. Reasons for a mid-term or even long-term effect based on a single injection of local anaesthetic are not exactly known. The CT-guided ONB is a fast, easy and safe procedure that may be useful for mid-term (weeks) and sometimes even long-term (months) treatment of hip pain.

MR-Guided vacuum biopsy of 206 contrast-enhancing breast lesions

PURPOSE

To determine the accuracy and clinical use of MR-guided vacuum biopsy (VB) of enhancing breast lesions.

MATERIAL AND METHODS

254 lesions were referred to MR-guided vacuum-assisted breast biopsy. In 43 (16 %) patients the indication was dropped because the lesions could not be identified at the time VB was scheduled. This was due to hormonal influences (n = 37), to too strong compression (n = 3) or to misinterpretation of the initial diagnostic MRI (n = 3). In 5 cases (2 %) VB was not performed due to obesity (n = 2); problems of access (n = 2) or a defect of the MR-unit (n = 1). VB was performed on altogether 206 lesions. In 4 cases (2 %) VB was unsuccessful. This was immediately realized on the post-interventional images. Thus a false negative diagnosis was avoided. Verification included excision of the cavity in cases with proven malignancy or atypical ductal hyperplasia (ADH) and (for benign lesions) retrospective correlation of VB-histology with pre-and postinterventional MRI and subsequent follow-up.

RESULTS

51/202 successful biopsies proved malignancy. In 7 cases ADH and in 144 cases a benign lesion was diagnosed. One DCIS was underestimated as ADH. All other benign or malignant diagnoses proved to be correct.

CONCLUSION

MR-guided VB allows reliable histological work-up of contrast-enhancing small lesions which are not visible by any other modality.

[Spectral transillumination of the female breast]

PURPOSE

Evaluation of wavelength-associated characteristics by transilluminating normal and pathological breast tissue.

METHOD

80 in vivo and 52 in vitro measurements were carried out with a Mammaspectrograph (Siemens AG, ZFE München). 31 patients had a carcinoma and 59 patients a benign breast lesion. Measurements were performed with an increment of 10 nm, wavelengths between 550-1100 nm.

RESULTS

Normal and pathological breast tissue could be characterised in the area of absorption maxima of fat, water and haemoglobin. Atrophic breast tissue has a remarkable transmission minimum at 930 nm. Tumors with a high number of cells and neovascularisation showed a strong absorption over the entire "diagnostic window" and a transmission minimum at 970 nm. Below 700 nm the high concentration of haemoglobin resulted in an increase of transmission. Less wavelength-associated characteristics were seen in tumors with mastopatically-transformed surrounding tissue.

CONCLUSION

To differentiate breast tissue, transillumination has to be performed in the area of absorption maxima of fat, water and haemoglobin.

[New knowledge regarding tumor cell inactivation and histological evaluation after radiofrequency therapy. Single case observation and in vitro proof of a new hypothesis]

In a study, a radiofrequency (RF) treatment was performed on a patient with a small breast cancer after vacuum biopsy. As usual in cases with a malignant diagnosis, surgical excision and axillary dissection followed. Histopathology revealed some residual tumor in the margin of the cavity. It could not be distinguished from vital tumor on the hematotoxylin eosin (HE) stain. Based on the correlation of MRI and histopathology after subsequent surgical excision, we did, however, presume that the residual was contained within the zone of inactivation. Thus the hypothesis arose that, if too high temperatures can be avoided, it might be possible to inactivate tumor cells without significantly impairing histopathologic assessment. This hypothesis was supported by the following in vitro experiment performed on a fresh specimen: An RF treatment was performed using temperatures up to 70 degrees C only. Half of the specimen underwent HE-staining, the other half vitality testing. The results indicate that if a given temperature range is strictly observed it appears possible to inactivate tissue before tissue sampling, since histopathologic diagnosis will not be impaired. Further technologic improvements may eventually allow to develop a pre-treatment method which might permit to avoid potential hematogenous tumor spread during subsequent biopsy.

[Plans of the German Roentgen Society and the Professional Association for Quality Assurance in Mammography]

A high level of quality is an unequivocal prerequisite for obtaining the highest possible accuracy in symptomatic patients and for reproducing the results concerning mortality reduction, which were obtained in large screening trials. Present deficiencies in Germany are due to legal regulations, which have not been updated and which are thus below European standard. Furthermore the quality assurance program has not proven sufficiently effective for mammography. In order to promote mammographic quality assurance, the German Roentgen Society proposes an accreditation program. The accreditation, which concerns A.) mammographic technique and positioning and B.) mammographic reporting is not obligatory, but will allow acquisition of special official certificates, which may support the patients to find doctors who perform and read mammograms with high quality and expertise. The accreditation shall be performed by personnel and/or institutions who are specifically trained surveyed.

International investigation of breast MRI: results of a multicentre study (11 sites) concerning diagnostic parameters for contrast-enhanced MRI based on 519 histopathologically correlated lesions

A multicentre study was undertaken to provide fundamentals for improved standardization and optimized interpretation guidelines of dynamic contrast-enhanced MRI. Only patients scheduled for biopsy of a clinical or imaging abnormality were included. They underwent standardized dynamic MRI on Siemens 1.0 (163 valid lesions > or = 5 mm) or 1.5 T (395 valid lesions > or = 5 mm) using 3D fast low-angle shot (FLASH; 87 s) before and five times after standardized bolus of 0.2 mmol Gd-DTPA/kg. One-Tesla and 1.5 T data were analysed separately using a discriminant analysis. Only histologically correlated lesions entered the statistical evaluation. Histopathology and imaging were correlated in retrospect and in open. The best results were achieved by combining up to five wash-in or wash-out parameters. Different weighting of false-negative vs false-positive calls allowed formulation of a statistically based interpretation scheme yielding optimized rules for the highest possible sensitivity (specificity 30%), for moderate (50%) or high (64-71%) specificity. The sensitivities obtained at the above specificity levels were better at 1.0 T (98, 97, or 96%) than at 1.5 T (96, 93, 86%). Using a widely available standardized MR technique definition of statistically founded interpretation rules is possible. Choice of an optimum interpretation rule may vary with the clinical question. Prospective testing remains necessary. Differences of 1.0 and 1.5 T are not statistically significant but may be due to pulse sequences.

In situ and minimally invasive breast cancer: morphologic and kinetic features on contrast-enhanced MR imaging

PURPOSE

This retrospective study was undertaken to investigate the morphologic and dynamic features of in situ and minimally invasive breast cancer on contrast-enhanced (c.-e.) MR imaging and to examine possible associations to pathology features.

MATERIAL AND METHODS

A total of 71 patients underwent MR imaging. T1-weighted FLASH-3D images were obtained before and after intravenous administration of Gd-DTPA. Histopathologic analysis of 78 lesions revealed ductal carcinoma in situ (DCIS) n = 50 and DCIS with microinvasion n = 28. MR features were correlated with histopathologic findings.

RESULTS

Enhancement in DCIS was focal (73%), diffuse (10%) or ductal (17%). No enhancement occurred in two cases (4%). In 65% enhancement speed was classified as delayed. There was a tendency toward a more ill-defined (83 vs. 43%) enhancement pattern in high grade DCIS and a more ductal (29 vs. 12%) and faster (50 vs. 29%) enhancement in comedo type DCIS. However, significant differences in the enhancement behaviour could neither be demonstrated between high grade and non high grade DCIS nor between comedo and non comedo type DCIS. No significant differences were noted between pure and microinvasive DCIS.

CONCLUSION

In this retrospective analysis the majority (96%) of DCIS lesions show contrast enhancement. However, in only about 50% of DCIS the criteria of a so-called 'typical' enhancement behaviour was fulfilled, that means strong, early, focal ill-circumscribed or ductal. Enhancement that follows a duct is often associated with malignancy, however this feature was only present in 17% of the cases. c.-e. MR imaging allowed the detection of 25 additional foci of DCIS. Therefore malignant in situ lesions can be present with atypical enhancement, and should be taken into consideration in high-risk patients in particular.

Stereotaxic vacuum core breast biopsy--experience of 560 patients

The purpose of our study was the assessment of the diagnostic value of vacuum core biopsy, which promises high accuracy. The material used were a digital stereotaxic biopsy table (Fischer Imaging) and a Mammotome-gun (Biopsys). A total of 560 patients with 594 predominantly indeterminate lesions underwent vacuum core biopsy (VCB). Verification was a follows: (a) demonstration of complete or partial removal of the lesion or replacement of the lesion by a small hematoma by comparison of the pre- and post-VCB mammogram; (b) reexcision of 105 malignant and 13 borderline lesions; (c) radiologic-histologic correlation; (d) 6-month-follow-up mammograms in 460 cases. Five puncture errors occurred which, however, were immediately recognized and VCB was repeated. Based on the above verification a 100% accuracy was achieved. Only one relevant hematoma that required surgical excision occurred. Except for one case mammographically any severe scaring was visible. Based on the excellent accuracy and excellent tolerance of the procedure VCB appears to be the future method of choice for the workup of those indeterminate mammographically detected lesions that up to now have still required surgical biopsy.

Vertigo after stapes surgery: the role of high resolution CT

CT findings in patients with vertigo after stapes surgery include a prosthesis shaft entering the vestibule and compressing the saccule, a complete dislocation of the stapes prosthesis, air bubbles and fluid collections within the vestibule and outside the oval window indicating a perilymphatic fistula, and bony fragments leading to compression of the basal saccule. Although immediate post-operative vertigo is often transient, patients with persistent or recurrent vertigo should be imaged as high resolution CT will determine the underlying cause in the majority of cases.

Neurosarcoidosis: evaluation with MRI

Clinical studies report a rate of 5% and autopsy results a rate of 25% of brain involvement in sarcoidosis. The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of patients with neurosarcoidosis. The MRI brain scans of 22 patients with sarcoidosis were retrospectively reviewed, along with the clinical information that was provided in the request form. All patients had signs and symptoms referable to the head and were examined with gadolinium enhancement. Cranial (facial) nerve paralysis was the most common clinical manifestation identified in 10 patients. A wide spectrum of MR findings was noted: Periventricular and white matter lesions on T2W spin echo images, mimicking multiple sclerosis (46%); multiple supratentorial and infratentorial brain lesions, mimicking metastases (36%); solitary intraaxial mass, mimicking high grade astrocytoma (9%); solitary extraaxial mass, mimicking meningioma (5%); leptomeningeal enhancement (36%). These findings are not specific for sarcoidosis and one must consider appropriate clinical circumstances in arriving at the correct diagnosis. In selected cases with isolated brain involvement, meningeal or cerebral biopsy may be required.

Value of spiral CT in patients with cricothyroid approximation

Cricothyroid approximation raises the vocal pitch by simulating contraction of the cricothyroid muscle with sutures. The aim of this study was to determine the role of spiral CT in patients scheduled for cricothyroid approximation. 29 transsexual patients were examined with spiral CT prior to and after laryngoplastic surgery. CT findings were correlated with phonographic findings in all patients. The average reduction of the cricothyroid distance was 6 mm (range 2-10 mm). Vocal pitch elevation was greatest in patients with the largest reduction of the cricothyroid distance. CT accurately determines the cricothyroid distance prior to and after surgery and is an ideal method for follow-up, especially in post-operative reversion towards a lower pitch. In addition, CT provides important data in determining the most appropriate extent and site of intracordal intervention to achieve a desired pitch elevation.

Spiral computed tomography before and after cricothyroid approximation

Cricothyroid approximation raises the vocal pitch by simulating the contraction of the cricothyroid muscle with sutures. The aim of this study was to determine the role of spiral computed tomography (CT) in patients scheduled for cricothyroid approximation. Twenty-nine transsexual patients were examined with spiral CT before and after laryngoplastic surgery. Computed tomography findings were correlated with phoniatric findings in all patients. The average reduction of the cricothyroid distance was 6 mm (range 2-10 mm). The vocal pitch elevation was more remarkable in the patient group with greater reduction of the cricothyroid distance. Computed tomography accurately determines the cricothyroid distance before and after surgery and is an ideal method for follow-up purposes, especially when there is a postoperative reversion towards a lower pitch. In addition, CT provides important data as to the most appropriate extent and site of intracordal intervention to be done for a desired pitch elevation.

Suspected acute appendicitis: is ultrasonography or computed tomography the preferred imaging technique?

OBJECTIVE

To compare the sensitivity and specificity of unenhanced spiral computed tomography (CT) and ultrasonography (US) in patients with suspected acute appendicitis.

DESIGN

Prospective study.

SETTING

University hospital, Germany.

SUBJECTS

120 consecutive patients with acute appendicitis as a differential diagnosis, whose clinical findings were not enough to make operation essential, but were too severe to send home.

INTERVENTIONS

CT and US of the appendix.

MAIN OUTCOME MEASURES

Sensitivity, specificity, and positive and negative predictive value.

RESULTS

The results were correlated with surgical and histopathological findings at appendicectomy or clinical follow-up. 93 patients had acute appendicitis, 27 patients did not. The sensitivity of CT was 95% and of US 87%. The corresponding specificities were 89% and 74%, positive predictive values 97% and 92%, negative predictive values 83% and 63%. In the 27 patients who did not have acute appendicitis, the correct diagnosis was established with CT in 14 patients and with US in eight.

CONCLUSION

CT is more sensitive and specific than US in patients suspected of having acute appendicitis, but in whom the presentation is equivocal. The use of unenhanced spiral CT led to a significant improvement in the accuracy of preoperative diagnosis and a lower negative appendicectomy rate.

Interventional MRI of the breast: lesion localisation and biopsy

With the growing use of breast MRI an increasing need exists for reliable MR-guided preoperative localisation or even MR-guided needle biopsy. In this article an overview is given of the different approaches and the present state of the art. With closed magnets the following approaches have been made: freehand localisation (similar to CT-guided freehand localisation), and freehand localisation combined with a frameless stereotaxic system operating with support by ultrasound. One localisation device for supine localisation and a thermoplastic mesh for breast stabilisation have been reported. Most investigators have used compression devices to immobilize the breast and prevent shift during needle insertion. Thus far, one immobilisation and aiming device has been designed for open magnets. A small number of experiences exist with interventions on open MR units using a navigation system. Wire localisations are presently a well-established procedure. Magnetic-resonance-guided needle biopsy has been accomplished in closed systems as well as by the use of breast immobilisation devices. However, problems still exist due to severe needle artefacts, tissue shift during the intervention and fast equalization of contrast enhancement in lesions with surrounding tissue. Therefore, needle biopsy is not recommended for lesions < 10 mm. Magnetic-resonance-guided vacuum biopsy is somewhat more invasive but promises to solve most of these problems.

Role of radiology in the diagnosis of neurosarcoidosis

Clinical studies report a rate of 5% and autopsy results a rate of 25% of brain involvement in sarcoidosis. The aim of this study was to evaluate the role of radiology in the diagnosis of patients with neurosarcoidosis. The chest radiographs and MRI brain scans of 22 patients with sarcoidosis were retrospectively reviewed, along with the information that was provided in the request form and clinical charts. All patients had neurological signs and symptoms; 21 patients were examined with contrast enhancement. Facial nerve paralysis was the most common clinical manifestation identified in 10 patients. A wide spectrum of MR findings was noted: periventricular high-signal lesions on T2-weighted images (46%); multiple supratentorial and infratentorial brain lesions (36%); solitary intra-axial mass (9%); solitary extra-axial mass (5%); and leptomeningeal enhancement (36%). Neurological signs and symptoms can be significant manifestations of sarcoidosis. Magnetic resonance imaging shows a wide spectrum of brain abnormalities associated with neurosarcoidosis. The patient's history and chest X-ray are helpful in arriving at the correct diagnosis, but in selected cases with isolated brain involvement biopsy may still be required.

[Direct in-vitro measurement of ultrasound velocity in carcinomas, mastopathic tissue, fatty tissue and fibroadenomas of the female breast]

PURPOSE

The study aimed to investigate ultrasound velocity (SV) in carcinomas, fibrocystic changes, fibroadenomas and fatty tissue of the female breast by means of direct in-vitro measurements. We intended to test whether or not differences in SV exist between the various types of tissue and whether the SV is a useful criterion to differentiate the different tissues.

METHOD

SV was measured by comparing transmission time of the ultrasound beam through the specimen and through water. Altogether 40 specimens (12 cancer, 14 fibrocystic changes = FCD, 10 fatty tissues, 3 fibroadenomas, and 1 mixed tissue) were analysed.

RESULTS

Velocity differed significantly between fat (1478.5 +/- 6.5 m/s) and tumor (1523.1 +/- 5.9 m/s) (p approximately 10(-11)) and between fat and FCD (1526.0 +/- 9.0 m/s) (p approximately 10(-12)). No significant differences and much overlap were seen between the ultrasound velocities of tumors and FCD. Ultrasound velocity in fibroadenomas (1533.2 +/- 3.8 m/s) was comparable with that in carcinomas and FCD.

CONCLUSIONS

We conclude that ultrasound velocity may add complementary information to echogenicity (B-scan). Thus, a locally exact correlation of echogenicity and sound velocity might allow for an improved tissue characterization.

[Routine skull CT in psychiatric diagnosis]

PURPOSE

To prospectively assess the spectrum of brain CT findings in psychiatric patients and to determine the number of patients that had an underlying cause for the symptoms.

PATIENTS AND METHODS

Over a period of six months, 142 patients (78 males, 64 females; median age 61 [18-91] years) were referred for CT brain scans. Their scans were reviewed, along with the clinical information that was provided in the request form. All the hard copies were reviewed to assess areas of ischaemia, infarction, atrophy, tumours, and haematomas. The majority of requests were to exclude vascular event or space-occupying lesions. Clinical indications included mood disorders (depression, mania), schizophrenic disorders, dementia, personality and behavioural disorders.

RESULTS

31 (22%) were normal. 111 (78%) had varying degrees of ischaemia, infarction and cerebral/cerebellar atrophy. 7 (4.9%) had space-occupying lesions which included two gliomas and five meningiomas. There were two chronic subdural haematomas and one arteriovenous malformation.

CONCLUSION

1. In our series, pathologic findings in "routine" brain CT's were encountered in 78%. 2. The incidence of brain tumours was 4.9%, compared with 0.00005% of the general population. 3. CT scanning in psychiatric patients is cost-effective and especially indicated when there is an atypical presentation, or inadequate response to standard treatment.

Imaging of recurrent esthesioneuroblastoma

Esthesioneuroblastoma is an uncommon neoplasm arising from the olfactory epithelium and characterized by frequent local recurrences. The purpose of this study was to determine the role of CT and MRI in the diagnosis of recurrent esthesioneuroblastoma. A total of 14 histologically confirmed recurrent esthesioneuroblastomas referred to our institution between 1986 and 1998 was retrospectively reviewed. All patients underwent both CT and MRI. The tumour recurrences displayed a variety of imaging characteristics and aggressiveness. They were typically expansile and destructive in their growth patterns. Erosion of the cribriform plate and involvement of the anterior cranial fossa were common findings. The CT and MRI appearances of recurrent esthesioneuroblastoma do not differ significantly from tumours imaged at initial presentation. Patients should receive close follow-ups and CT/MRI examinations for several years beyond diagnosis, as early diagnosis of recurrent disease predicts survival.

MR-guided percutaneous excisional and incisional biopsy of breast lesions

The aim of this study was the realisation and clinical application of MR-guided vacuum biopsy for percutaneous excisional and incisional biopsy of enhancing breast lesions. A breast biopsy system and procedure have been developed which allow precise and safe access to breast lesions in any location and use of vacuum biopsy (VB) under MR guidance. Fifty-one patients with 55 MR-detected lesions were examined. Verification of these diagnoses included re-excision histology of all 14 malignancies and for benign lesions retrospective correlation of histology and imaging, assessment of complete or partial removal of the enhancing area directly after VB (40 of 40 lesions) and follow-up MRI (33 of 40 lesions), which in contrast to conventional needle biopsy can be used as proof of representative removal. Fifty-four of 55 procedures (including 15 lesions </= 5 mm and another 26 lesions of 5-10 mm size) were successful. One failure was caused by incorrect use of the VB gun. Vacuum biopsy yielded 14 malignancies and 40 benign lesions. With the available verification techniques all diagnoses proved correct. Percutaneous VB became possible under MR guidance. With minimal invasion it allowed increased certainty and accuracy even for very small lesions.

[Role of magnetic resonance imaging in the diagnosis of neurosarcoidosis]

Neurological involvement is a significant cause of morbidity and mortality in patients with sarcoidosis. The aim of this study was to evaluate the role of magnetic resonance imaging (MRI) in the diagnosis of patients with neurosarcoidosis. The MRI brain scans of 22 patients with sarcoidosis were retrospectively reviewed, along with the clinical information provided in the request form. All patients had signs and symptoms referable to the head and were examined with gadolinium enhancement. Cranial (facial) nerve paralysis was the most common clinical manifestation identified in 10 patients. A wide spectrum of MR findings was noted: periventricular and white matter lesions on T2 W spin echo images, mimicking multiple sclerosis (46%); multiple supratentorial and infratentorial brain lesions, mimicking metastases (36%); solitary intraaxial mass, mimicking high-grade astrocytoma (9%); solitary extraaxial mass, mimicking meningioma (5%); leptomeningeal enhancement (36%). The diagnosis of neurosarcoidosis is often difficult, particularly so in patients who lack either pulmonary or systemic manifestations of sarcoidosis. MRI shows a wide spectrum of brain abnormalities associated with neurosarcoidosis. These findings, however, are not specific for sarcoidosis and one must consider appropriate clinical circumstances in arriving at the correct diagnosis. In selected cases with isolated brain involvement, meningeal or cerebral biopsy may be required.

Computed tomography and magnetic resonance imaging features of olfactory neuroblastoma: an analysis of 22 cases

The computed tomography (CT) and magnetic resonance imaging (MRI) studies of 22 patients with a histologically proven olfactory neuroblastoma were retrospectively reviewed. The tumours displayed a variety of imaging characteristics and aggressiveness. The expansile tendency of olfactory neuroblastoma is characterised by bowing of the sinus walls. The destructive aspect is manifested as tumour replacing the turbinates, septum, and sinus walls with extension into contiguous areas. The density/signal and enhancement characteristics are non-specific. Olfactory neuroblastoma should be suspected in all ages following identification of a mass in the superior nasal cavity demonstrating both expansile and destructive growth patterns. The otorhinolaryngologist and the radiologist should be aware of this tumour entity, as early diagnosis appropriately guides therapy and predicts survival.

[New methods for minimal invasive assessment of uncertain mammography and MRI tomography findings]

Results of 3 minimal invasive techniques for breast biopsy of clinically occult lesion are presented. 1. Mammographically guided Site-Select biopsies allow removal of tissue in one piece using a large diameter core biopsy instrument (similar to the ABBI-principle). However the overlying subcutaneous tissue is saved. No technical problems occurred in 13/13 diagnostic biopsies. Complete removal was, however, only possible in 2/4 tumors < 1 cm due to tissue shift during insertion of the instrument. 2. Mammographically guided vacuum biopsy also allows contiguous removal of areas of 1.2-1.8 cm diameter, while blood is suctioned out, as well. 3 stereotaxic miscalculations were immediately recognized. Diagnostic accuracy in 405 biopsies so far is 100%. The examination was very well tolerated by the patients. 3. By means of a specially developed biopsy coil and vacuum biopsy percutaneous in- or excisional biopsy of enhancing lesions visible by MRI alone has been realized by us for the first time. 24/25 diagnoses are definitely representative--as proven by lack of enhancement after biopsy. One diagnosis, which was uncertain due to overlying blood, is being followed. Minimal invasive methods may open up new perspectives.

Retrospective analysis for evaluation of the value of contrast-enhanced MRI in patients treated with breast conservative therapy

PURPOSE

The aim of this study was to assess the value of contrast-enhanced (c.-e.) MRI in the follow-up of patients with conservatively treated breast cancer since detection and exclusion of malignancy may interfere significantly with posttherapeutic changes within the treated breast.

MATERIAL AND METHODS

A total of 207 patients with a history of limited surgery and radiation therapy underwent MR imaging, 40 patients were examined 0-12 months and 167 patients were examined later than 12 months after radiotherapy. Suspicious or indeterminate findings were suggested by clinical examination or conventional imaging in 80 studies. In 127 women, MRI was performed within breast tissue that was difficult to assess due to scarring or dense breast tissue.

RESULTS

Recurrent carcinoma was confirmed in 27 patients by surgical biopsy. All 27 carcinomas, except for one with a slow signal increase, demonstrated early rise of signal intensity on dynamic T1-weighted contrast enhanced images. During the first year after therapy, the diagnostic accuracy could not be improved by additional use of c.-e. MRI. Differentiation between posttherapeutic changes and recurrent carcinoma was frequently not possible because of strong and sometimes early and ill-circumscribed enhancement. Later than 12 months after therapy enhancement decreased significantly, thus the false positive calls could be reduced from 49 (conventional imaging) to 12 (conventional imaging plus MRI). A total of 12 of 26 recurrences and multifocality in 4/5 cases were diagnosed by MR imaging alone at this time interval.

CONCLUSION

In the first year after therapy, c.-e. MRI is only indicated in selected cases. The results later than 12 months emphasize that c.-e. MRI may contribute significant additional information. It allows better distinction of posttherapeutic fibrosis from recurrent carcinoma and proved to be able to detect recurrent disease more sensitive and at an earlier stage.

[Automated mammary sonography and mammography: the differentiation of benign and malignant breast lesions]

PURPOSE

A prospective study on the differentiation of breast lesions was carried out using experimental combination schemes of mammography and automatic sonography.

MATERIALS AND METHODS

X-ray mammograms and a B image from automatic sonography of 39 malignant and 41 benign lesions as well as 40 cases without lesions were separately examined by four experienced diagnosticians. The observers differentiated the findings mammographically and by measurement in the B images.

RESULTS

For two examiners the combination of mammography and automatic sonography gave with regard to the differentiation of breast lesions an improvement in sensitivity of 3 or 5% and in specificity of 31 and 18%, respectively, as compared to mammography alone while for the other two examiners an improved specificity of 21 and 36%, respectively, was accompanied by an 8 and 10% decrease in sensitivity as compared to mammography alone.

CONCLUSIONS

The differentiating criteria from automatic sonography and mammography can, in principle, be used to evaluate the dignity of breast lesions. However, an optimization is necessary since the improvement in specificity does not compensate the loss in sensitivity.

Minimally invasive stereotaxic vacuum core breast biopsy

The purpose of our study was the assessment of the diagnostic value of vacuum core biopsy, which promises high accuracy by minimally invasive percutaneous excision of 1-2 cm3 of tissue. The materials used were a digital stereotaxic biopsy table (Fischer Imaging) and a Mammotome-gun (Biopsys). A total of 236 patients with 261 predominantly indeterminate lesions (indeterminate: 230; suspicious: 26; malignant: 5) underwent vacuum core biopsy (VCB). Verification was as follows: (a) demonstration of complete or partial removal of the lesion or replacement of the lesion by a small hematoma by comparison of the pre- and post-VCB mammogram; (b) reexcision of 45 malignant and 6 borderline lesions; (c) radiologic-histologic correlation; and (d) 6-month-follow-up mammograms in 129 cases. Two VCBs were not possible because very fine microcalcifications could not be visualized. Two puncture errors occurred which, however, were immediately recognized and VCB was repeated. Based on the above verification a 100 % accuracy was achieved. No relevant side effects occurred. Except for 2 cases mammographically hardly any scarring was visible. Based on the excellent accuracy and excellent tolerance of the procedure VCB appears to be the future method of choice for the workup of those indeterminate mammographically detected lesions that up to now have still required surgical biopsy.

Contrast-enhanced magnetic resonance imaging of the breast: interpretation guidelines

In the past decade, most studies have shown that in selected indications of breast imaging, the overall accuracy can be improved by the additional use of contrast-enhanced magnetic resonance imaging (MRI). The sensitivity of contrast-enhanced MRI for invasive malignancy is >98%; reported specificity, however, ranges from 37% to 97%. This range of values is predominantly caused by different patient preselection and interpretation criteria. Other factors, such as technique (e.g., choice of pulse sequence and echo time, slice thickness, reduction in artifacts, dosage of contrast agent, and methods for elimination of fat signal), hormonal influences (menstrual cycle and hormonal replacement therapy), and levels of verification, influence the accuracy and reproducibility of contrast-enhanced MRI. An appropriate application of MRI is highly desirable because of the increased costs of imaging, increased rates of biopsy due to false-positive results, and possibility of false-negative results caused by technical failures and interpretation errors. We present an overview of the sensible application and interpretation of contrast-enhanced MRI of the breast based on our experience and on published data.

[Optical mammography in preoperative patients]

AIM

Research concerning alternative methods of breast imaging that may supplement or even replace mammography appears interesting for further improvement of diagnostic accuracy, for possible cost reduction and increased patient acceptance and compliance.

METHOD/PATIENTS

119 pre-operative patients (59 carcinomas, 60 benign lesions) were examined on a prototype breast scanner in this fundamental research project. Images of the compressed breast that display light transmission and phase shift at wavelengths of 690, 750, 790 and 860 nm were obtained with scanning steps every 2 mm. Based on these images we could calculate further images.

RESULTS

Images displaying the division of two original transmission images appeared most useful, whereas phase images generally did not yield relevant additional information. A total of 51 out of 59 carcinomas (mean diameter: 21 mm) were visualised and diagnosed. Specificity in respect of lesion diagnosis was 28%. If surrounding tissue was included in the evaluation, the specificity dropped to 9%.

DISCUSSION

The method is not sufficiently developed and well-tried for clinical use. Future research might consider the development of tumour-specific contrast media.

Detection of malignant and benign breast lesions with an automated US system: results in 120 cases

PURPOSE

To evaluate clinically an automated ultrasound (US) system for detecting benign and malignant breast lesions.

MATERIALS AND METHODS

A prototype automated US system was used to examine 119 patients: 38 patients with 39 proved malignant breast lesions (7-50 mm), 41 patients with 41 proved benign breast lesions (8-40 mm), and 40 patients without breast lesions. The device yields a three-dimensional set of B-mode scans and reconstructed US images comparable to mammograms. All patients had undergone mammography. Four radiologists who had not performed the examinations independently assessed the mammograms and US images to detect benign and malignant breast lesions.

RESULTS

Each of the four readers did not recognize one to three detectable malignant lesions on mammograms, one to two detectable malignant lesions on US images, two to four detectable benign lesions on mammograms, and five to seven detectable benign lesions on US images. All readers identified the 39 cancers with at least one of the modalities. The 40 cases without lesions were diagnosed correctly more frequently on the US images by three readers and on the mammograms by one reader.

CONCLUSION

Depiction of breast lesions at automated US is reproducible. Automated US is complementary to mammography.

[Vacuum punch biopsy under digital stereotaxic control, a new procedure in percutaneous diagnostic incision and excision biopsy of mammographic findings: initial experience]

PURPOSE

To evaluate a digital, stereotactically controlled vacuum punch biopsy method.

MATERIAL AND METHOD

In 60/61 female patients a vacuum punch biopsy (14 G) was performed under digital stereotactic control; by means of a single biopsy 1-2 cm3 of tissue was obtained. In one patient the examination could not be carried out because of insufficient microcalcification. Excision biopsies were performed because of doubtful microcalcification (24), focal lesions (35) or abnormal tissue architecture (1).

RESULTS

48 of the biopsies proved benign, 2 showed dysplasias, 5 in situ and 5 invasive carcinomas. In all cases the histological and radiological diagnoses were in agreement. The possibility of a non-presentative biopsy could be excluded with a high degree of certainty because of the accurate localisation and the coherent tissue samples; this produced significant increase in diagnostic certainty. Subsequent haematomas seen mammographically (58/60) are smaller (1-1.5 cm) than for conventional percutaneous punch biopsies because of the effect of suction. The examination was well tolerated (there were no significant haematomas and no infection). Problems consisted of one case of bleeding (due to little experience) and one incorrect localisation which was immediately recognised.

DISCUSSION

If the high degree of accuracy, which is expected, can be confirmed, the procedure would appear suitable for replacing diagnostic operative biopsies of non-characteristic mammographic finding.