Carpal tunnel syndrome assessment with diffusion tensor imaging: Value of fractional anisotropy and apparent diffusion coefficient

OBJECTIVES

To quantitatively assess carpal tunnel syndrome (CTS) with DTI by evaluating two approaches to determine cut-off values.

METHODS

In forty patients with CTS diagnosis confirmed by nerve conduction studies (NCs) and 14 healthy subjects (mean age 58.54 and 57.8 years), cross-sectional area (CSA), apparent diffusion coefficient (ADC) and fractional anisotropy (FA) at single and multiple levels with intraobserver agreement were evaluated.

RESULTS

Maximum and mean CSA and FA showed significant differences between healthy subjects and patients (12.85 mm² vs. 28.18 mm², p < 0.001, and 0.613 vs. 0.524, p=0.007, respectively) (10.12 mm² vs. 19.9 mm², p<0.001 and 0.617 vs. 0.54, p=0.003, respectively), but not maximum and mean ADC (p > 0.05). For cut-off values, mean and maximum CSA showed the same sensitivity and specificity (93.3 %). However, mean FA showed better sensitivity than maximum FA (82.6 % vs. 73.9 %), but lower specificity (66.7 % vs. 80 %), and significant correlation for maximum CSA, 97 % (p < 0.01), with good correlation for maximum ADC and FA, 84.5 % (p < 0.01) and 62 % (p=0.056), respectively.

CONCLUSIONS

CSA and FA showed significant differences between healthy subjects and patients. Single measurement at maximum CSA is suitable for FA determination. Key Points • DTI showed that FA is stronger than ADC for CTS diagnosis. • Single- and multiple-level approaches were compared to determine FA and ADC. • Single-level evaluation at the thickest MN cross-sectional area is sufficient.

Feasibility of Ultrasound-Guided Sacroiliac Joint Injections in Children Presenting with Sacroiliitis

PURPOSE

To evaluate the feasibility and effectiveness of US-guided sacroiliac joint injection in the treatment of sacroiliitis in children.

MATERIALS AND METHODS

This study was approved by the institutional review board and informed oral and written consent was obtained from the patients and their parents. In 13 patients (7 females and 6 males), 9 - 16 years (mean +/- std 11.39 +/-1.98), 18 sacroiliac joint (SI joint) injections were performed under US guidance. All patients suffered from severe sacroiliitis. US scanning was performed using a linear-array transducer operating at 5 - 18 MHz. Rating of the patients pain using a 0 - 10 dolorimetry scale on a visual analog score (VAS) was recorded before, immediately after and 3 months after injection to monitor severity and therapeutic response.

RESULTS

Injection could be performed in all patients without complication and showed good response immediately and 3 months after the injection with a decrease of the VAS (from mean +/- std 9.44 +/- 1.097 to 3.89 +/- 3.82, p < 0.001 and to 0.56 +/- 1.097, p < 0.05, respectively).

CONCLUSION

US-guided SI joint injection was feasible in all children, relatively quick and easy to perform and appeared effective in the treatment of children with sacroiliitis.

Sonoelastographic Findings of Carpal Tunnel Injection

PURPOSE

The objectives of this study were to compare sonoelastographic color findings of the perineural area between carpal tunnel syndrome patients and healthy volunteers, and to analyze elastographic findings in that area before and immediately after intracarpal tunnel injection in carpal tunnel syndrome patients.

MATERIALS AND METHODS

We studied both hands of 15 healthy volunteers (7 men, 8 women; mean age: 60.1 years, range: 41 - 88 years) and 72 hands from 70 patients with symptomatic carpal tunnel syndrome (24 men, 46 women; mean age: 54.2 years, range: 24 - 83 years). Sonoelastographic color distribution was assessed in the perineural area between the median nerve and adjacent flexor tendons. The color elastograms were graded using the following system: Grade 1 as red (softest), grade 2 as yellow (soft), grade 3 as green (hard), grade 4 as blue (hardest). The patients were treated with corticosteroid injection and were reassessed with sonoelastography immediately after the injection.

RESULTS

The median color grading in the perineural area of carpal tunnel syndrome patients was grade 3 (3.1 ± 0.3, mean ± 95 % Cl), which was stiffer than that of healthy volunteers (grade 1, 1.9 ± 0.4) (p < 0.0001). Immediately after injection, the diffusion of the injected fluid was observed as having a softer appearance (grade 1, 1.4 ± 0.2) (p < 0.0001).

CONCLUSION

The perineural area surrounding the median nerve in carpal tunnel syndrome patients was stiffer than that in healthy volunteers. Diffusion of the injected fluid in the carpal tunnel was seen as a softer finding after injection in real time using sonoelastography.

EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 2: Clinical applications

The clinical part of these Guidelines and Recommendations produced under the auspices of the European Federation of Societies for Ultrasound in Medicine and Biology EFSUMB assesses the clinically used applications of all forms of elastography, stressing the evidence from meta-analyses and giving practical advice for their uses and interpretation. Diffuse liver disease forms the largest section, reflecting the wide experience with transient and shear wave elastography . Then follow the breast, thyroid, gastro-intestinal tract, endoscopic elastography, the prostate and the musculo-skeletal system using strain and shear wave elastography as appropriate. The document is intended to form a reference and to guide clinical users in a practical way.

EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 1: Basic principles and technology

The technical part of these Guidelines and Recommendations, produced under the auspices of EFSUMB, provides an introduction to the physical principles and technology on which all forms of current commercially available ultrasound elastography are based. A difference in shear modulus is the common underlying physical mechanism that provides tissue contrast in all elastograms. The relationship between the alternative technologies is considered in terms of the method used to take advantage of this. The practical advantages and disadvantages associated with each of the techniques are described, and guidance is provided on optimisation of scanning technique, image display, image interpretation and some of the known image artefacts.

Contrast-enhanced ultrasonography for the detection of joint vascularity in arthritis--subjective grading versus computer-aided objective quantification

PURPOSE

To compare joint inflammation assessment using subjective grading of power Doppler ultrasonography (PDUS) and contrast-enhanced ultrasonography (CEUS) versus computer-aided objective CEUS quantification.

MATERIALS AND METHODS

37 joints of 28 patients with arthritis of different etiologies underwent B-mode ultrasonography, PDUS, and CEUS using a second-generation contrast agent. Synovial thickness, extent of vascularized pannus and intensity of vascularization were included in a 4-point PDUS and CEUS grading system. Subjective CEUS and PDUS scores were compared to computer-aided objective CEUS quantification using Qontrast® software for the calculation of the signal intensity (SI) and the ratio of SI for contrast enhancement.

RESULTS

The interobserver agreement for subjective scoring was good to excellent (κ = 0.8 - 1.0; P < 0.0001). Computer-aided objective CEUS quantification correlated statistically significantly with subjective CEUS (P < 0.001) and PDUS grading (P < 0.05). The Qontrast® SI ratio correlated with subjective CEUS (P < 0.02) and PDUS grading (P < 0.03). Clinical activity did not correlate with vascularity or synovial thickening (P = N. S.) and no correlation between synovial thickening and vascularity extent could be found, neither using PDUS nor CEUS (P = N. S.).

CONCLUSION

Both subjective CEUS grading and objective CEUS quantification are valuable for assessing joint vascularity in arthritis and computer-aided CEUS quantification may be a suitable objective tool for therapy follow-up in arthritis.

US-guided therapy of calcific tendinopathy: clinical and radiological outcome assessment in shoulder and non-shoulder tendons

PURPOSE

To analyze the effectiveness and complication rate of ultrasound (US)-guided perforation and lavage using a two-needle technique with 16 - 18 G needles in the treatment of patients with calcific tendinopathy in the shoulder, elbow, hip, and knee by radiological and clinical follow-up.

MATERIALS AND METHODS

A retrospective chart review was performed and 40 patients (13 male, 27 female; mean age, 53.5 years; range 24 -74 years) were identified as having received US-guided perforation and lavage due to symptomatic calcific tendinopathy of the rotator cuff tendons, triceps, extensor and flexor tendons at the elbow, rectus femoris tendon and patellar tendons. The radiographic outcome was assessed by comparison of the size and quality of the calcification before and 6 weeks after the procedure. On US images, the quality of the acoustic shadow was assessed, together with other alterations of the tendon and surrounding tissue. Patients were interviewed by telephone to assess the clinical outcome regarding pre-treatment and post-treatment pain and tendon function.

RESULTS

34 shoulder tendons and 6 non-shoulder tendons were identified. The mean calcium reduction was 39.9 mm(2) (range, 0 - 215; p < 0.001), while 80 % of patient showed a resolution of more than 60 % resulting in good clinical improvement. A very low complication rate was found (1 partial tear).

CONCLUSION

The US-guided perforation and lavage technique is an effective and safe treatment for rotator cuff calcifications as well as for other body tendons. Although the two-needle technique and large needles were used in this study, a very low complication rate was detected.

Real-time sonoelastography: findings in patients with symptomatic achilles tendons and comparison to healthy volunteers

PURPOSE

Real-time sonoelastography (SE), a newly introduced ultrasound technique, has already shown conclusive results in breast, prostate, and thyroid tumor diagnostics. This study investigated the performance of SE for the differentiation of Achilles tendon alterations of tendinopathy compared to clinical examination and conventional ultrasound (US).

MATERIALS AND METHODS

Achilles tendons in 25 consecutive patients with chronic Achilles tendinopathy and 25 healthy volunteers were examined clinically by US and by SE.

RESULTS

In the healthy volunteers, SE showed the tendon to be hard (93 %), while distinct softening was found in 57 % of the patients. SE showed more frequent involvement of the distal (64 %) and middle third (80 %) than the proximal third (28 %) of the Achilles tendon. Using SE a mean sensitivity of 94 %, specificity of 99 %, and accuracy of 97 % were found when clinical examination was used as the reference standard. The correlation to US was 0.89. Mild softening was found in 7 % of the healthy volunteers and in 11 % of the patients.

CONCLUSION

Our results emphasize that only distinct softening of Achilles tendons is comparable to clinical examination and US findings. However, mild softening might be explained by very early changes in tissue elasticity in the case of Achilles tendinopathy, which should be assessed in follow-up studies.

Diagnostic values of history and clinical examination to predict ultrasound signs of chronic and acute enthesitis

OBJECTIVE

To examine the diagnostic values of history of chronic enthesitic pain and clinical signs of acutely inflamed entheses to predict ultrasound (US) signs of enthesitis.

METHODS

Cohort study of 21 consecutive rheumatic out-patients (female/male 18/3) with suspected multiple enthesitis and 12 controls (female/male 10/2). 429 enthesal sites according to the Maastricht Ankylosing Spondylitis Entheses Score (MASES) were evaluated by history, clinical examination, B-mode and power Doppler US. Sensitivity and specificity of history suggesting chronic enthesitic pain and clinical examination suggesting acute enthesitis were calculated using corresponding US findings as reference standard.

RESULTS

Diagnostic accuracy widely varied between different MASES sites. Sensitivity and specificity of selected MASES points were 66.7 - 86.4% and 85.0 - 91.7% for history and 71.4 - 87.0% and 47.4 - 75.0% for clinical examination, respectively (p<0.05 for each).

CONCLUSION

At specific enthesal sites, history of chronic enthesitic pain and clinical signs of acute inflammation are sensitive and specific for the diagnosis of chronic and/or acute inflammation.

Reconstruction of the digital flexor pulley system: a retrospective comparison of two methods of treatment

The rare injury of closed rupture of the A2 and A3 flexor pulleys was treated using two non-encircling techniques of pulley reconstruction. Thirteen patients were treated with an extensor retinaculum graft (Group A). At a mean follow-up time of 48 months, the average PIP flexion was 97%, the power grip strength 96%, the pinch grip strength 100% and the thickening 94% of the uninjured side. Ten patients were treated with a free palmaris longus tendon grafts (Group B). At a mean follow-up time of 57 months, the average PIP flexion was 94%, the power grip strength 98%, the pinch grip strength 100% and the thickening 95% of the uninjured side. In both groups, finger extension was unrestricted. The Buck Gramcko score included 10 excellent, two good and one fair result in Group A and seven excellent, two good and one fair result in Group B. Both techniques proved beneficial. All climbers returned to their previous standard and all non-climbers regained full finger dexterity in their previous job.

Sonographie synovialer und erosiver entzündlicher Veränderungen

High-frequency sonography enables excellent detection of early erosions and synovial proliferations. Power Doppler sonography (PDUS) allows for an improved characterization of articular and peritendinous augmented volume, because detection of hypervascularity correlates with inflammatory activity and further is helpful in differentiation from effusion and inactive pannus. The use of contrast media improves the sensitivity of vascularity detection, because they allow for a delineation of vessels at the microvascular level. This is of increased interest, as the development of new therapeutic options targeting the microvascular level calls for earlier diagnosis and optimal assessment of disease activity. Because of good availability, cost effectiveness, and patient acceptance, sonography facilitates early diagnosis of synovial proliferations and erosions as well as therapy follow-up.