Preoperative imaging of Charcot neuroarthropathy

With about 4 million diabetics in germany and presumed inclination over the following years the treatment of diabetic complications like diabetic foot will become an even more important point. The management of Charcot’s foot has undergone fundamental change in the last few years. Formerly, treatment was almost exclusively limited to non surgical measures; since the late 1990’s, however, current practice has shifted to early, stage-appropriate surgical therapy. The aim of the present prospective study was to investigate the value of positron emission tomography (PET) in the pre-operative work-up of Charcot’s foot. PET were compared to magnetic resonance tomography (MRI). Patients, methods: MRI and PET imaging were used as part of the preoperative work-up in 18 patients with Type II diabetes mellitus. The diagnosis of Charcot’s foot requiring surgical treatment were made on the basis of clinical and radiologic criteria. Results: Of 46 Charcot’s lesions confirmed at surgery, 44 and 35 were detected by means of PET and MRI, respectively. PET can be used in the work-up of patients with metal implants where the MRI does not show adequate findings. PET shows the areas of detritus formation exhibit only moderately increased glucose metabolism and at visual interpretation do not usually impress as typical for acute osteomyelitis. Average SUV values stood at 1.2 (range: 0.5–2.9). Conclusions: The differentiation between Charcot’s lesions and florid osteomyelitis provides the surgeon with important additional information, which is often unavailable from MRI. Because of this important additional data, PET could be considered preferable to morphologic imaging (CT, projection radiography) in the preoperative work-up of Charcot’s foot.

Bildgebende Verfahren in der Frühdiagnostik rheumatischer Veränderungen der Hände

PURPOSE

Besides the use of conventional x-rays in the diagnostic work-up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The aim of this study was to compare the diagnostic value of ultrasound of the hands with proven methods such as conventional x-rays, low-field MRI and 3P-Sz.

METHODS

A total of 30 patients were studied using a 1 day protocol with ultrasound, 3P-Sz, MRI and x-ray of the hands. Images were visually assessed by two blinded nuclear medicine physicians and radiologists and classified as RA typical and non-RA typical changes. All methods were compared to the summarized findings interpreted by a rheumatologist after 2 years.

RESULTS

Of the 30 patients, 19 presented with clinical symptoms of initial changes due to rheumatoid arthritis. Ultrasound revealed 14/19 patients with the correct diagnosis. Conventional x-rays indicated 11/19 patients, while 3P-Sz (100%) and low-field MRI (95%) showed high sensitivity. It was possible to differentiate between inflammation and inconspicuous findings.

CONCLUSIONS

An experienced examiner can use ultrasound effectively for the initial diagnosis of RA. Based on its low cost, ultrasound is a valid alternative to conventional x-rays.

[Preoperative imaging of Charcot neuroarthropathy: Does the additional application of (18)F-FDG-PET make sense?]

With about 4 million diabetics in germany and presumed inclination over the following years the treatment of diabetic complications like diabetic foot will become an even more important point. The management of Charcot's foot has undergone fundamental change in the last few years. Formerly, treatment was almost exclusively limited to non surgical measures; since the late 1990's, however, current practice has shifted to early, stage-appropriate surgical therapy. The aim of the present prospective study was to investigate the value of positron emission tomography (PET) in the pre-operative work-up of Charcot's foot. PET were compared to magnetic resonance tomography (MRI).

PATIENTS, METHODS

MRI and PET imaging were used as part of the preoperative work-up in 18 patients with Type II diabetes mellitus. The diagnosis of Charcot's foot requiring surgical treatment were made on the basis of clinical and radiologic criteria.

RESULTS

Of 46 Charcot's lesions confirmed at surgery, 44 and 35 were detected by means of PET and MRI, respectively. PET can be used in the work-up of patients with metal implants where the MRI does not show adequate findings. PET shows the areas of detritus formation exhibit only moderately increased glucose metabolism and at visual interpretation do not usually impression as typical for acute osteomyelitis. Average SUV values stood at 1.2 (range: 0.5-2.9).

CONCLUSIONS

The differentiation between Charcot's lesions and florid osteomyelitis provides the surgeon with important additional information, which is often unavailable from MRI. Because of this important additional data, PET could be considered preferable to morphologic imaging (CT, projection radiography) in the preoperative work-up of Charcot's foot.

[Diagnosis of initial changes in patients suffering from rheumatoid arthritis. Two years follow up control with a low-field magnetic resonance scanner, 3-phase bone scintigraphy and conventional x-ray]

Besides conventional x-ray, in the diagnostic work up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The AIM of this study was to compare the diagnostic value of a newly developed low field MRI with proven methods such as conventional x-ray and 3P-Sz.

PATIENTS, METHODS

42 patients were studied using a one days protocol with 3P-Sz, MRI, and x-ray of the hands with yearly follow up examinations. Images were visually assessed by two blinded nuclear medicine physicians and radiologists and classified as RA-typical and non-RA-typical changes. All methods were compared to the summarised findings interpreted by a rheumatologist in consideration of the Ritchie articular index as gold-standard.

RESULTS

24/42 patients presented with clinical symptoms of initial changes by rheumatoid arthritis. Conventional x-ray revealed in 20/24 patients within the correct diagnosis in the study period. On the other hand 3P-Sz and low field MRI concordantly showed all 24 patients with initial changes due to RA. Time of detection showed variations with a tendency to later findings by conventional x-ray.

CONCLUSIONS

In the diagnostic work up of initial changes conventional x-ray should be the first choice in imaging. Our findings suggest that MRI represents an equally sensitive method for the diagnosis of initial changes due to RA in the region of the hands as compared to the 3P-Sz. The limitation of the low field MRI is the small field of view, so we prefer 3P-Sz or high field MRI in the diagnosis of patients with suspected RA.

Diagnosis of initial changes in patients suffering from rheumatoid arthritis

In der Initialdiagnostik bei rheumatoider Arthritis (RA) werden neben der Projektionsradiographie (PR) auch die Magnetresonanztomographie (MRT) und die 3-PhasenSkelettszintigraphie (3P-SZ) eingesetzt. Ziel dieser Studie war es, bei Patienten mit Verdacht auf RA die Wertigkeit der PR, der 3P-SZ und der MRT anhand von Verlaufsbeobachtungen über 2 Jahre zu beurteilen. Patienten, Methoden: Bei 42 Patienten wurden am selben Tag je eine 3P-SZ, Niederfeld-MRT und PR der Hände im dorsovolaren Strahlengang durchgeführt. Verlaufskontrollen erfolgten im jährlichen Abstand. Alle Bilder wurden von jeweils zwei erfahrenen Radiologen/ Nuklearmedizinern befundet und in rheumatypisch und nicht rheumatypisch unterteilt. Als Goldstandard diente die abschließende klinische Diagnose des Rheumatologen unter Berücksichtigung des Ritchie-articular-Index. Ergebnisse: Bei 24/42 Patienten wurde die Diagnose einer initialen RA gestellt. In der PR konnte bei 20/ 24 Patienten im zeitlichen Verlauf die richtige Diagnose gestellt werden. Demgegenüber wurde sowohl in der 3P-SZ als auch in der MRT bei allen 24 Patienten eine beginnende RA erkannt. Lediglich im Detektionszeitpunkt gab es Variationen mit insgesamt tendenziell späterer Diagnosestellung in der PR. Schlussfolgerung: In der bildgebenden Initialdiagnostik der RA ist die PR weiterhin als Verfahren der ersten Wahl anzusehen. In der weiterführenden Diagnostik von unklaren Befunden stellt die Niederfeld-MRT ein der 3P-SZ annähernd vergleichbar sensitives Verfahren dar. Trotzdem sollten – wenn möglich – aufgrund des geringen Field-of-view neben der 3P-SZ zur weiteren Abklärung unklarer Befunde Hochfeldtomographen bevorzugt werden.

[Systematic characterization of sonomorphological changes in the early stage of rheumatoid arthritis]

AIM

The early stage of rheumatoid arthritis (RA) is primarily manifested in the soft tissue of the hand. Although ultrasound (US) is regarded as an important imaging process in diagnostic medicine, precise characterization of sonomorphological changes has not yet been undertaken.

METHOD

20 patients with RA were examined with US. Two radiologists described semiquantitatively the characteristics of synovial changes in the hand in a consensus-based process and measured the synovial width. Statistical methods were used to determine whether the various synovial changes differed significantly and to identify the most frequent locations of changes.

RESULTS

On the basis of the significant differences in morphology and synovial width, it is possible to distinguish between unremarkable findings, pannus tissue and band-like synovitis. Pannus tissue is most frequently found on the finger flexor tendons (FFT), the metacarpophalangeal joints (MCP) and the tendon of M. extensor carpi ulnaris (ECU). Band-like synovitis exhibits an uncharacteristic distribution pattern with a slight propensity to favour these locations.

CONCLUSION

The FFT, MCP joints and ECU tendons are particularly important in systematic US screening of the hand for the purpose of establishing reliable evidence of inflammatory changes. Different stages of RA can be identified on the basis of the characteristic types of synovitis and the number of joints and tendons affected.

[Radiological interventions in inflammatory bowel disease]

INTRODUCTION

Abscesses, fistulas,hemorrhages and stenoses are common complications of inflammatory bowel diseases. This study provides an overview on various methods of radiological intervention and the clinical usefulness of these methods is analyzed.

METHODS

The success rate of percutaneous abscess drainage (PAD), embolisation of hemorrhages and dilatation of bowel stenoses is reviewed and current literature is addressed. Success rate is defined in terms of cure rate and need for subsequent surgery.

RESULTS

After PAD, surgery can be avoided during the observation period in about 50% of patients with abscesses due to Crohn's disease and diverticulitis. Preoperative PAD reduces the degree of invasiveness and thus the risk of surgery. Abscess recurrence is found with the same frequency following surgery or PAD. Bowel dilatation can be performed both with radiological and with endoscopic guidance.Embolisation of GI-hemorrhage is technically feasible, but the indication should be limited to strictly selected cases.

CONCLUSIONS

In treating abscesses and fistulas associated with Crohn's disease and diverticulitis, PAD is a valuable treatment option. Embolisation or dilatation are restricted to rare cares.

[Diagnosis of initial changes in the hand of patients with rheumatoid arthritis--comparison between low-field magnetic resonance imaging, 3-phase bone scintigraphy and conventional x-ray]

Besides conventional X-rays, in the diagnostic work up of initial changes in patients suffering from rheumatoid arthritis (RA), 3-phase bone scintigraphy (3P-Sz) is as well established as magnetic resonance imaging (MRI). The aim of this study was to compare the diagnostic value of the newly developed low field MRI with the proven methods X-rays and 3P-Sz.

METHODS

65 patients (47f, 18m; 20-86 yrs) were studied on a one day protocol with 3P-Sz (550 MBq Tc-99m DPD), MRI and X-rays of the hands. Images were visually analysed by two blinded nuclear medicine physicians and radiologists and classified as a) RA-typical, b) inflammatory, non-RA-typical and c) non inflammatory changes. All methods were compared to 3P-Sz as golden standard.

RESULTS

In comparison to 3P-Sz, low field MRI presents with almost equal sensitivity and specificity in rheumatoid-typical and inflammatory changes. Conventional X-rays revealed in arthritis-typical changes as well as in inflammatory changes a significantly lower sensitivity and also a lower negative predictive value while specificity equals the one of MRI. Quantitative analysis of 3P-Sz using ROI-technique unveiled significantly higher values in patients with rheumatoid arthritis than in those with no inflammatory changes.

CONCLUSION

MRI represents an equally sensitive method in the initial diagnosis of rheumatoid-typical and inflammatory changes in the region of the hands as compared to the 3P-Sz. Besides the basic diagnosis with conventional X-rays, 3P-Sz is still the recommended method of choice to evaluate the whole body when RA is suspected. Additionally, quantitative analysis of the 3P-Sz using the ROI technique in the region of the hands reveals statistically significant results and should therefore be taken into account in the assessment of inflammatory changes.

Diagnosis of initial changes in patients suffering from rheumatoid arthritis

Zur Diagnostik initialer Veränderungen bei rheumatoider Arthritis (RA) werden neben der Projektionsradiographie (PR) im bilddiagnostischen Stufenkonzept die 3-Phasen- Skelettszintigraphie (3P-Sz) und die Magnetresonanz- Tomographie (MRT) eingesetzt. Ziel dieser Studie war es, die neu entwickelte Niederfeld-MRT mit den etablierten Verfahren (PR, 3P-Sz) in der Initialdiagnostik der RA an der Hand zu vergleichen. Methode: Bei 65 Patienten (47 w, 18 m; 20-86 Jahre) wurden an einem Tag 3P-Sz (550 MBq Tc-99m DPD), Niederfeld-MRT und PR der Hände durchgeführt. Alle Bilder wurden von zwei erfahrenen Nuklearmedizinern/Radiologen geblindet befundet und unterteilt in a) rheumatypische, b) entzündliche, nicht rheumatypische und c) nicht entzündliche Veränderungen sowie der 3P-Sz als Goldstandard gegenüber gestellt. Ergebnisse: Im Vergleich zur 3P-Sz zeigt die Niederfeld-MRT bei nahezu gleicher Sensitivität gegenüber rheumatypischen und entzündlichen Veränderungen nur eine gering niedrigere Spezifität. Bei der PR war sowohl bei rheumatypischen als auch bei entzündlichen Veränderungen die Sensitivität vermindert bei gleicher Spezifität wie die Niederfeld-MRT. Die quantitative Auswertung der 3P-Sz mittels ROI-Technik ergab signifikant höhere Werte bei rheumatypischen Veränderungen. Schlussfolgerung: Die Niederfeld-MRT stellt ein der 3PSz vergleichbar sensitives Verfahren in der Initialdiagnostik zum Nachweis rheumatypischer und entzündlicher Veränderungen im Bereich der Hände dar. Neben der Basisuntersuchung der PR empfiehlt sich die 3P-Sz durch Erhebung eines Ganzkörperstatus sowie quantitativer ROI-Technik für die weiterführende Diagnostik bei Verdacht auf RA.

Fibrous architecture of the dorsal aponeurosis of the thumb

BACKGROUND

The extensor apparatus of the thumb displays obvious structural variations in its proximo-distal expanse. Its associated tissue comes in close relation to the dorsal aponeurosis that have varying topographical relationships to the extensor apparatus of the thumb. This region is especially important as the location of pathological and repair processes.

METHODS

In this anatomical study using a modified embedding technique a histological description of the fibrous architecture of the dorsal aponeurosis and the peritendinous connective tissue body of the thumb is presented.

RESULTS

The dorsal connective tissue of the thumb forms different layers of collagen lamellae as a peritendinous system around the tendons of the long and short extensor tendons of the thumb. This peritendinous laminar system as the main part of the dorsal aponeurosis is connected with both the capsular and the retinacular ligaments of the thumb.

CONCLUSIONS

It will be shown that the structural variations of the dorsal aponeurosis and peritendinous connective tissue are an expression of different topographical zones of stress along the lines of a balanced musculofibrous stabilization of the interphalangeal joint of the thumb. The expansions in the peritendinous intercellular space act as defined gliding spaces or clefts of the extensor apparatus.