Extremity anomalies associated with Robinow syndrome

Robinow syndrome, a rare genetic disorder, is characterized by skeletal dysplasia with, among other anomalies, extremity and hand anomalies. There is locus heterogeneity and both dominant and recessive inheritance. A detailed description of associated extremity and hand anomalies does not currently exist due to the rarity of this syndrome. This study seeks to document the hand anomalies present in Robinow syndrome to allow for improved rates of timely and accurate diagnosis. A focused assessment of the extremities and stature was performed using clinical examination and standard photographic images. A total of 13 patients with clinical and molecular diagnosis consistent with dominant Robinow syndrome or recessive Robinow syndrome were evaluated. All patients had limb shortening, the most common of which was mesomelia; however, rhizomelia and micromelia were also seen. These findings are relevant to clinical characterization, particularly as Robinow syndrome has classically been defined as a "mesomelic disorder." A total of eight distinct hand anomalies were identified in 12 patients with both autosomal recessive and dominant forms of Robinow syndrome. One patient did not present with any hand differences. The most common hand findings included brachydactyly, broad thumbs, and clinodactyly. A thorough understanding of the breadth of Robinow syndrome-associated extremity and hand anomalies can aid in early patient identification, improving rates of timely diagnosis and allowing for proactive management of sequelae.

Comparing 10 kVp and 15% Rules in Extremity Radiography

PURPOSE

To investigate the viability of the 10 kVp rule as a substitute for the 15% rule in obtaining extremity radiographs of high diagnostic quality while lowering patient radiation dose. The intention of this substitution is to allow technologists a simpler and quicker calculation for use in clinical settings to benefit patients without disrupting workflow.

METHODS

Three anteroposterior or posteroanterior exposures were made on 3 anthropomorphic phantom extremities: hand, knee, and shoulder. Thermoluminescent dosimeters (TLDs) were placed at the center of each phantom; a new TLD was used for each exposure. Exposures were made on a Defininium 8000 digital radiography system (General Electric) using the unaltered, system-preset techniques used by the authors' imaging department, techniques adapted from the 10 kVp rule, and techniques adapted from the 15% rule. The detector exposure indicator from each image was used to compare image quality among the 3 exposures in each group. Entrance skin dose measured from the TLDs also were compared among the 3 exposures for each extremity. One TLD was used as a control to determine the amount of background radiation to which the TLDs were exposed.

RESULTS

The detector exposure indicator remained in optimal range for every exposure with both applied rules as well as the system-preset techniques. Entrance skin dose was lower for both rules in the shoulder and hand trials, with the possibility of error during exposure and reading of the system-preset technique used on the knee phantom. Entrance skin dose also was lower for the shoulder and hand exposures when using the 10 kVp techniques compared with the 15% rule techniques.

DISCUSSION

Aside from unknown entrance skin dose errors during knee imaging, no failures of the tested rules were found. Using manual technique selection rather than automatic exposure control allowed for consistent manipulation of technical factors. TLDs allowed for relatively reliable and quick readings from each exposure, although they could have been the cause of an error in the exposure reading of the preset technique of the knee. Environment and equipment were unchanged to maintain consistency.

CONCLUSION

Results demonstrated that both the 15% rule and the 10 kVp rule successfully maintained or slightly improved image quality according to the detector exposure indicators. The results also demonstrated lowered patient dose according to the entrance skin doses. Based on these results, the 10 kVp rule might be a reasonable substitute for the 15% rule. Further research should be conducted with more repetitions that include digital radiography equipment for a wider range of examinations.

Monitoring Vascular Compromise Using Ultrasound After Free Tissue Transfer

OBJECTIVES

To report the clinical utility of high-resolution ultrasound (US) for monitoring vascular compromise after free tissue transfer.

METHODS

Fifty-two tissue transfers in the extremities were included in this study. Blood flow around the anastomotic pedicle and subcutaneous tissue of the grafted flap was monitored with pulsed color and power Doppler US whenever the conventional monitoring method, comprising the bedside assessment of the temperature, capillary refill, and flap color, showed abnormalities until 1 week after reconstruction.

RESULTS

All flaps were indicated for US monitoring, with 44 flaps showing Doppler signals in each position, even though conventional flap monitoring showed an abnormality. Forty of the 44 flaps showed no flap failure, whereas the remaining 4 flaps developed partial necrosis. Abnormal US findings were noted in 8 of the 52 flaps. Ultrasound revealed interruption of venous blood flow around the anastomotic pedicle in 6 of 8 flaps. Emergent exploration revealed venous occlusion at the anastomotic pedicle, similar to the US finding. In 2 of the 8 flaps, US showed no blood flow to either the anastomotic pedicle or subcutaneous tissue. Emergent exploration revealed arterial occlusion at the anastomotic pedicle. Seven of the 8 reexplored flaps were salvaged after revision surgery with complete flap survival. Partial flap survival was noted in 1 case, but complete flap failure was avoided.

CONCLUSIONS

Ultrasound is a useful adjunct that enables a direct assessment of perfusion in grafted tissues, which may reduce unnecessary exploration when conventional flap monitoring shows an abnormality.

Origin of the 31 P MR signal at 5.3 ppm in patients with critical limb ischemia

An unknown intense signal (P_un ) with a mean chemical shift of 5.3 ppm was observed in ³¹ P MR spectra from the calf muscles of patients with the diabetic foot syndrome. The aim of the study was to identify the origin of this signal and its potential as a biomarker of muscle injury. Calf muscles of 68 diabetic patients (66.3 ± 8.6 years; body mass index = 28.2 ± 4.3 kg/m² ) and 12 age-matched healthy controls were examined by (dynamic) ³¹ P MRS (3 T system, ³¹ P/¹ H coil). Phantoms (glucose-1-phosphate, P_i and PCr) were measured at pH values of 7.05 and 7.51. At rest, P_un signals with intensities higher than 50% of the P_i intensity were observed in 10 of the 68 examined diabetic subjects. We tested two hypothetical origins of the P_un signal: (1) phosphorus from phosphoesters and (2) phosphorus from extra- and intracellular alkaline phosphate pools. 2,3-diphosphoglycerate and glucose-1-phosphate are the only phosphoesters with signals in the chemical shift region close to 5.3 ppm. Both compounds can be excluded: 2,3-diphosphoglycerate due to the missing second signal component at 6.31 ppm; glucose-1-phosphate because its chemical shifts are about 0.2 ppm downfield from the P_i signal (4.9 ppm). If the P_un signal is from phosphate, it represents a pH value of 7.54 ± 0.05. Therefore, it could correspond to signals of P_i in mitochondria. However, patients with critical limb ischemia have rather few mitochondria and so the P_un signal probably originates from interstitia. Our data suggest that the increased P_un signal observed in patients with the diabetic foot syndrome is a biomarker of severe muscular damage.

Surgical Ectrodactyly Repair Using Limb-lengthening and Bone Tissue Engineering Techniques in a Toy Dog Breed

BACKGROUND/AIM

Bone tissue engineering is an emerging field of regenerative medicine that holds promise for the restoration of bones affected by trauma, neoplastic diseases, and congenital deformity. During the past decade, bone tissue engineering has evolved from the use of biomaterials that can only replace small areas of damaged bone, to the use of scaffolds in which grafts can be seeded before implantation. This case report proposes an alternative option for a veterinary patient suffering from ectrodactyly, which is one of several congenital deformities in dogs. A 2-month-old male toy poodle dog with ectrodactyly was treated using several stages of surgery involving pancarpal arthrodesis, limb lengthening, and bone tissue engineering techniques.

RESULTS AND CONCLUSION

Over a period of 2 years, the operated limb gained almost the same function as the contralateral limb. Bone tissue engineering techniques can be used for the treatment of congenital deformities in dogs.

IMRiS phase II study of IMRT in limb sarcomas: Results of the pre-trial QA facility questionnaire and workshop

INTRODUCTION

Soft tissue sarcomas of the extremities (STSE) are rare malignancies. We report current UK practice for immobilisation of soft tissue sarcoma of STSE, as part of the initial study set-up within the IMRiS trial, a phase II study of intensity modulated radiotherapy (IMRT) in primary bone and soft tissue sarcoma.

METHODS

A facility questionnaire (FQ) was circulated to 29 IMRiS centres investigating the variation in immobilisation devices, planning techniques, and imaging protocols. A workshop was held to address concerns raised by centres. It focused on STSE immobilisation and patient set-up. Robustness of patient set-up at each centre was evaluated based on the following criteria: evidence of local set-up audit, calculation of margins based on set-up audit results, imaging frequency, and number of patients treated per centre per annum.

RESULTS

Twenty-seven (93%) questionnaires were returned. 30% (8/27) of responders routinely treated STSE with IMRT. The remaining 70% (19/27) had little or no experience with IMRT for STSE. Vacuum bags were the most frequent immobilisation device (9/27), followed by thermoplastic shells (7/27). Nine centres had audited their local set-up; however, only 4 had calculated margins in response to the results. Ten centres were classified as having high level of robustness.

CONCLUSIONS

Immobilisation devices and planning techniques for STSE are inconsistent across centres. Robustness of set-up is an important tool to ensure quality of results in a multicentre trial setting with such different levels of experience. The IMRiS trial Quality Assurance programme encourages centres to assess robustness of set-up through local audit and subsequent calculation of treatment margins.

IMPLICATIONS FOR PRACTICE

This is the first study that used robustness criteria to tailor QA support to individual centres.

Reference data on in vitro anatomy and indentation response of tissue layers of musculoskeletal extremities

The skin, fat, and muscle of the musculoskeletal system provide essential support and protection to the human body. The interaction between individual layers and their composite structure dictate the body's response during mechanical loading of extremity surfaces. Quantifying such interactions may improve surgical outcomes by enhancing surgical simulations with lifelike tissue characteristics. Recently, a comprehensive tissue thickness and anthropometric database of in vivo extremities was acquired using a load sensing instrumented ultrasound to enhance the fidelity of advancing surgical simulations. However detailed anatomy of tissue layers of musculoskeletal extremities was not captured. This study aims to supplement that database with an enhanced dataset of in vitro specimens that includes ultrasound imaging supported by motion tracking of the ultrasound probe and two additional full field imaging modalities (magnetic resonance and computed tomography). The additional imaging datasets can be used in conjunction with the ultrasound/force data for more comprehensive modeling of soft tissue mechanics. Researchers can also use the image modalities in isolation if anatomy of legs and arms is needed.

Is 64-Row Multi-Detector Computed Tomography Angiography Equal to Digital Subtraction Angiography in Treatment Planning in Critical Limb Ischemia?

BACKGROUND

Critical limb ischemia (CLI) represents the end stage of peripheral arterial disease (PAD). It is defined as a chronic ischemic rest pain, ulcers or gangrene, attributable to proven arterial occlusive disease. Intra-arterial digital subtraction angiography (IA DSA) still represents the gold standard for the evaluation of steno-occlusive lesions, but it has greatly been replaced with non-invasive multi-detector computed tomography angiography (MDCTA). The purpose of this prospective study was to compare diagnostic performance of MDCTA versus DSA in treatment planning in patients with CLI according to TransAtlantic Inter-Society Consensus Document on Management of Peripheral Arterial disease (TASC II).

SUBJECTS AND METHODS

The study was designed as prospective; it was conducted from March 2014 to August 2016, and included 60 patients with symptoms of CLI, Fontaine stage III and IV. MDCTA of the peripheral arteries was performed first, followed by DSA. The lesions of aorto-iliac, femoro-popliteal and infra-popliteal regions were classified according to the TASC II guidelines, and inter-modality agreement between MDCTA and DSA was determined by using Kendall's tau-b statistics.

RESULTS

Inter-modality agreement was statistically significant in all three vascular beds, with excellent agreement >0.81 in aortoiliac and femoropopliteal regions, and a very good agreement >0.61 in infrapopliteal region. Treatment recommendations based on MDCTA findings and DSA findings were identical in 54 (90%) patients. In one patient (1.7%), CTA was not interpretable. In five patients (8.3%), CTA findings disagreed with DSA findings in regard to the preferable treatment option.

CONCLUSION

64-row MDCT angiography is highly competitive to DSA in evaluation of steno-occlusive disease and treatment planning in patients with critical limb ischemia.

Ultrasound Imaging of Disorders of Small Nerves of the Extremities: Less Recognized Locations

Ultrasound is a well-proven imaging modality for showing peripheral nerve disorders and guiding perineural injections. The aim of this review is to focus on small peripheral nerve abnormalities, which are usually not recognized by sonologists. In fact, most of these small nerves have a tiny diameter (<2 mm), and their anatomy is less familiar. We describe the most common causes of small peripheral nerve disorders, providing an accurate description of their anatomic locations and relationships with adjacent structures; we also focus on technical hints that may help in their evaluation.

Portable infrared imaging for longitudinal limb volume monitoring in patients with lymphatic filariasis

BACKGROUND

The Global Programme to Eliminate Lymphatic Filariasis (LF) emphasizes hygiene, exercise, and other measures to reduce morbidity and disability related to LF. We recently reported that a portable, three-dimensional, infrared imaging system (3DIS) provides accurate limb volume measurements in patients with filarial lymphedema. To assess the practical utility of repeated 3DIS measurements for longitudinal lymphedema management, we examined intraday and day-to-day leg volume changes in adults with filarial lymphedema in southern Sri Lanka.

METHODOLOGY AND PRINCIPAL FINDINGS

We assessed 41 participants with lower extremity lymphedema (stages 1-6) in their homes in the mornings (6:00-9:00 AM) and afternoons (2:00-6:00 PM) of three days within one calendar week. Two examiners performed replicate 3DIS volume measurements at each visit. Median coefficient of variation among replicate volume measurements was 1.7% (IQR 1.1% - 2.3%) for left legs and 2.2% (IQR 1.6% - 2.8%) for right legs. Median intraday volume increase was 3.0%. Range among daily volume measurements tended to be lower for afternoon measurements (median 2.25%, IQR 1.4%- 5.4%) than for morning measurements (median 3.0%, IQR 1.4% - 8.4%).

CONCLUSIONS AND SIGNIFICANCE

Limb volume measurements by 3DIS are accurate and reproducible, and this technique is feasible for use in patients' homes. We have developed practical suggestions for optimal outcomes with 3DIS. Duplicate measurements should be performed and repeat assessments should be done at approximately the same time of day to minimize bias. Duplicate measures that vary by more than 8% should prompt review of scanning technique with a repeat measurement. With proper training and attention to technique, 3DIS can be a valuable tool for healthcare workers who work with lymphedema patients.

Variation in appendages in early Cambrian bradoriids reveals a wide range of body plans in stem-euarthropods

Traditionally, the origin and evolution of modern arthropod body plans has been revealed through increasing levels of appendage specialisation exhibited by Cambrian euarthropods. Here we show significant variation in limb morphologies and patterns of limb-tagmosis among three early Cambrian arthropod species conventionally assigned to the Bradoriida. These arthropods are recovered as a monophyletic stem-euarthropod group (and sister taxon to crown-group euarthropods, i.e. Chelicerata, Mandibulata and their extinct relatives), thus implying a radiation of stem-euarthropods where trends towards increasing appendage specialisation were explored convergently with other euarthropod groups. The alternative solution, where bradoriids are polyphyletic, representing several independent origins of a small, bivalved body plan in lineages from diverse regions of the euarthropod and mandibulate stems, is only marginally less parsimonious. The new data reveal a previously unknown disparity of body plans in stem-euarthropods and both solutions support remarkable evolutionary convergence, either of fundamental body plans or appendage specialization patterns.

Dual Near-Infrared-Emissive Luminescent Nanoprobes for Ratiometric Luminescent Monitoring of ClO- in Living Organisms

The difficulty of near-infrared (NIR) ratiometric detection imaging lies in the lack of high-efficiency NIR probes and the overlapping interference between two emission peaks. To achieve more accurate detection in living organisms, dual NIR-emissive luminescent nanoprobes were designed under the same excitation at 808 nm. The Er³⁺ ion-doped nanoparticles were employed as a reference with their fluorescence emission at 1525 nm. Meanwhile, a cyanine dye molecule (Cy925) was combined on the surface of nanoparticles as the ClO^- recognition site with its NIR emission at 925 nm. The ratiometric nanoprobe relied on the ratio of aforementioned two separated NIR peaks ( I_925nm/ I_1525nm), featuring deeper imaging penetration depth and low autofluorescence. This nanoprobe was verified to be sensitive and highly selective to ClO^- through photoluminescence titration. The in vitro detection experiment developed reasonable work curves, guaranteeing that we can detect the change in concentration of ClO^- in mice limbs with arthritis through in vivo imaging experiments.

Angioleiomyoma of the Extremities: Findings on Ultrasonography and Magnetic Resonance Imaging

OBJECTIVES

The purpose of this study was to describe the features of angioleiomyomas of the extremities on ultrasonography (US) and magnetic resonance imaging (MRI).

METHODS

We retrospectively reviewed the US and MRI findings of 29 pathologically confirmed cases of angioleiomyomas of the extremities in 29 patients. Twenty patients underwent only US; 7 patients underwent only MRI; and 2 patients underwent US and MRI. Clinical data and histopathologic specimens were reviewed.

RESULTS

There were 19 women and 10 men. The mean patient age was 48.9 years (range, 23-80 years). On US, angioleiomyomas were located primarily in the subcutaneous fat layer (n = 20 [91%]), were oval (n = 17 [77%]), had well-circumscribed margins (n = 22 [100%]), had hypoechoic protrusions on one or both ends (n = 9 [41%]), had a homogeneous echo texture (n = 17 [ 77%]), had posterior acoustic enhancement (n = 20 [91%]), and had color Doppler flow (n = 20 [91%]). On MRI, the masses showed heterogeneous enhancement (n = 7 [88%]) and enhancing structures on one or both ends (n = 4 [50%]) on contrast-enhanced T1-weighted images.

CONCLUSIONS

Angioleiomyoma of the extremities is usually a well-circumscribed oval mass with a homogeneous echo texture and occasionally hypoechoic protrusions on US and shows heterogeneous enhancement with occasionally enhancing structures on one or both ends of the mass on MRI. Therefore, it should be included in the differential diagnosis of a soft tissue mass that has protruding structures from one or both ends.

[Update on gunshot wounds to extremities]

Due to recent rampage and terror attacks in Europe, gunshot wounds have become a focus of attention even though they are still rare in Europe. Approximately 50% of gunshot wounds affect the extremities and to understand the sequelae, a basic knowledge of wound ballistics is indispensable. The energy transmitted from the bullet to the tissue is responsible for the severity of the injury and is dependent on the type of weapon and ammunition. A differentiation is made between low-energy injuries caused, e.g. by pistols and high-energy injuries mostly caused by rifles. The higher energy transfer to the tissue in high-energy injuries, results in a temporary wound cavity in addition to the permanent wound channel with extensive soft tissue damage. High-energy gunshot fractures are also more extensive compared to those of low energy injuries. Debridement seems to be necessary for almost all gunshot wounds. Fractures should be temporarily stabilized with an external fixator due to contamination.

Ultrasound Bone Fracture Sensing and Data Communication: Experimental Results in a Pig Limb Sample

Approximately 6.3 million fractures occur each year in the United States alone. Accurately monitoring the progression of fracture healing is essential to be able to advise patients when it is safe to return to normal activity. The most common method used to confirm and monitor fracture healing is the acquisition of multiple radiographic images over the many months required for healing. This imaging method uses large expensive equipment and exposes patients to high levels of ionizing radiation. In the study described here, we tested another technology for monitoring fracture healing that could minimize the need for multiple radiographic images. We tested a piezoelectric transducer fixed to the surface of a bone that uses electromechanical impedance spectroscopy to measure simulated fractures and transmits the measurement data to an acoustic receiver located externally on the skin surface.

3D Ultrasound Imaging of Residual Limbs With Camera-Based Motion Compensation

Ultrasound is a cost-effective, readily available, and non-ionizing modality for musculoskeletal imaging. Though some research groups have pursued methods that involve submerging the transducer and imaged body segment into a water bath, many limitations remain in regards to acquiring an unloaded volumetric image of an entire human limb in a fast, safe, and adequately accurate manner. A 3D dataset of a limb is useful in several rehabilitative applications including biomechanical modeling of soft tissue, prosthetic socket design, monitoring muscle condition and disease progression, bone health, and orthopedic surgery. This paper builds on previous work from our group and presents the design, prototyping, and preliminary testing of a novel multi-modal imaging system for rapidly acquiring volumetric ultrasound imagery of human limbs, with a particular focus on residual limbs for improved prosthesis design. Our system employs a mechanized water tank setup to scan a limb with a clinical ultrasound transducer and 3D optical imagery to track motion during a scan. The iterative closest point algorithm is utilized to compensate for motion and stitch the images into a final dataset. The results show preliminary 2D and 3D imaging of both a tissue-mimicking phantom and residual limbs. A volumetric error compares the ultrasound image data obtained to a previous MRI method. The results indicate potential for future clinical implementation. Concepts presented in this paper could reasonably transfer to other imaging applications such as acoustic tomography, where motion artifact may distort image reconstruction.

Trichilemmal Cyst: Clinical and Sonographic Features

OBJECTIVES

In this study, we retrospectively reviewed the clinical and sonographic features of patients with trichilemmal cysts.

METHODS

Sonographic findings of 54 cases of trichilemmal cysts were retrospectively analyzed from 50 patients, including 4 cases of proliferating trichilemmal cysts. Associated factors of internal calcification-positive cases were also evaluated.

RESULTS

The mean age of the 50 patients was 43.4 years (range, 15-80 years) and the female-to-male ratio was 1.3. Overall, 68% of the trichilemmal cysts in the 54 lesions were located in the scalp, and 15% were located in the extremities. All 54 lesions were preoperatively examined by sonography and showed well-defined, oval-shaped structures located in subcutaneous soft tissues close to the dermis. Of the 54 lesions, 72% were hypoechoic masses, 89% were heterogeneous, and 65% had internal calcification. Among the internal calcification-positive cases, the mean age of the patients was 43.4 years, and the female-to-male ratio was 0.6. Of these lesions, 83% were located in the scalp. We did not find any significant association between calcification, age, or sex (P = .993 and P = .99); however, lesions present in the scalp were significantly associated with internal calcification (P = .005). 81% of the 54 lesions displayed posterior enhancement. but the color Doppler sonography of all lesions revealed no vascularization.

CONCLUSIONS

Trichilemmal cysts should be considered to diagnose of well-defined, hypoechoic lesions with internal calcification and posterior sound enhancement in the subcutaneous soft tissues of the scalp or extremities upon sonography.

Estimation of effective doses from MDCT and CBCT imaging of extremities

Little research has been published on the radiation burden of cone beam computed tomography (CBCT) in comparison with multi-row detector computed tomography (MDCT) for extremity imaging. This manuscript reports effective doses produced by standard and reduced dose imaging protocols for a 128-slice MDCT unit and a dedicated extremity imaging device using CBCT technology. Anthropomorphic phantoms with x-ray attenuation characteristics simulating adult hand-wrist, foot-ankle, and knee areas were modified to receive optically stimulated luminescent dosimeters (OSL). Standard and lower kVp reduced dose (Lite) exposures were compared. Effective doses for four age groups (five years old to adult) were calculated following 2007 recommendations of the ICRP. Standard CBCT imaging protocols produced effective doses (1.3-21.1 μSv) that were on the order of daily US ubiquitous background radiation doses. CBCT doses were on average 90% less than comparable MDCT views of the same anatomy (9.1-204 μSv). Child doses were significantly greater than adult doses (p = 0.0001). CBCT doses could be further reduced by 36%-51% with Lite exposure protocols. These protocols can be recommended for children and in cases where increased image noise will not interfere with the diagnostic task.

Real-time 3D Photoacoustic Visualization System with a Wide Field of View for Imaging Human Limbs

Background: A breast-specific photoacoustic imaging (PAI) system prototype equipped with a hemispherical detector array (HDA) has been reported as a promising system configuration for providing high morphological reproducibility for vascular structures in living bodies. Methods: To image the vasculature of human limbs, a newly designed PAI system prototype (PAI-05) with an HDA with a higher density sensor arrangement was developed. The basic device configuration mimicked that of a previously reported breast-specific PAI system. A new imaging table and a holding tray for imaging a subject's limb were adopted. Results: The device's performance was verified using a phantom. Contrast of 8.5 was obtained at a depth of 2 cm, and the viewing angle reached up to 70 degrees, showing sufficient performance for limb imaging. An arbitrary wavelength was set, and a reasonable PA signal intensity dependent on the wavelength was obtained. To prove the concept of imaging human limbs, various parts of the subject were scanned. High-quality still images of a living human with a wider size than that previously reported were obtained by scanning within the horizontal plane and averaging the images. The maximum field of view (FOV) was 270 mm × 180 mm. Even in movie mode, one-shot 3D volumetric data were obtained in an FOV range of 20 mm in diameter, which is larger than values in previous reports. By continuously acquiring these images, we were able to produce motion pictures. Conclusion: We developed a PAI prototype system equipped with an HDA suitable for imaging limbs. As a result, the subject could be scanned over a wide range while in a more comfortable position, and high-quality still images and motion pictures could be obtained.

Correlation of L-Dex Bioimpedance Spectroscopy with Limb Volume and Lymphatic Function in Lymphedema

Background: Bioimpedance spectroscopy (BIS) is an established tool for the measurement of extracellular fluid in lymphedema. This study assesses the validity of BIS measurements using the l-Dex^® for evaluating the effectiveness of interventions to treat lymphedema. Measurements are correlated with limb volume, assessment of pitting edema, physiologic measures of lymphatic function, and response to surgical intervention. Three l-Dex BIS metrics are compared. Methods and Results: This retrospective study of prospectively collected data identified consecutive patients with lymphedema. l-Dex BIS measurements, limb volume measurements using perometry, transport index (TI) evaluation using radioisotope lymphoscintigraphy, staging using indocyanine green (ICG) fluorescent lymphography, and clinical evaluation of degree of pitting edema were compared to examine correlations. l-Dex BIS metrics included the l-Dex ratio, absolute difference between the affected and unaffected extremities, and their unadjusted ratio. The study included 26 patients with 70 sets of evaluations. There were significant correlations between the l-Dex ratio and limb volume ratio (LVR) using perometry, the degree of pitting edema, TI evaluation using lymphoscintigraphy, and staging using ICG lymphography. Of the l-Dex BIS metrics, the l-Dex ratio correlated most closely with all measures (ρ = 0.71-0.94, p < 0.0001). Following complete decongestive therapy, the mean decrease in the l-Dex ratio was 48.3% whereas the corresponding mean reduction in limb volume was 13.8% (ρ = 0.19; p = 0.65); subsequent physiological surgery including lymphovenous bypass and vascularized lymph node transfer resulted in an average reduction in l-Dex ratio of 36.1% and mean limb volume reduction of 25.2% (ρ = 0.38; p = 0.27). Conclusions: L-Dex BIS measurements demonstrate face, construct, and criterion validity, and correlate with clinical assessment, LVR, physiologic measures of lymphatic function, and response to conservative and surgical intervention. The L-Dex ratio correlates most closely with all measures and is the recommended metric when using BIS.

MRI surveillance for local recurrence in extremity soft tissue sarcoma

INTRODUCTION

The role of MRI in surveillance for local recurrence (LR) remains uncertain in extremity soft tissue sarcoma (STS). The aims of this study were 1) to examine the usefulness of MRI in detecting LR, 2) to identify the characteristics of LR detected by MRI, and 3) to examine whether MRI surveillance is associated with oncologic outcome.

MATERIALS AND METHODS

477 patients who had regular surveillance for LR after surgery for extremity STS were reviewed. Surveillance was performed by routine MRI in 325 patients or other imaging modalities in 152 patients.

RESULTS

The rate of MRI-detected LR, defined as clinically undetectable LR identified on MRI, was 10.5% in the MRI surveillance cohort. The detection rates of MRI-detected LR were significantly higher in the patients with high risk of LR. MRI-detected LRs were more commonly located in the thigh or buttock (p = 0.005), were smaller (p = 0.001) and had LRs without mass formation (p = 0.007) than non-MRI-detected LRs. On Kaplan-Meier analysis, patients with MRI-detected LR tended to have better post-LR survival (p = 0.104).

CONCLUSION

Routine MRI surveillance can detect a significant number of clinically undetectable LRs in extremity STS especially for LRs in the thigh or buttock, small LRs or LRs without mass formation.

Imaging lymphatics in human normal and lymphedema limbs-Usefulness of various modalities for evaluation of lymph and edema fluid flow pathways and dynamics

The human lymphatic system morphology and function still remain largely unknown to clinicians and biologists. How does the lymphatic vascular system look like in comparison to the blood transport system, how does lymph flow, where does capillary filtrate accumulate in cases with lymphatic obstruction caused by inflammation, trauma, and cancer therapy, remain as basic questions. Visualization of the lymphatic pathways and dynamics of lymph flow, and in cases of obstruction, the localization of the capillary filtrate/edema fluid accumulation becomes indispensable. The contemporary methods only partly meet these requirements. Since the early 1950s of the 20th century only few specific clinical methods of imaging of limb lymphatics are being used in human clinic. Each of the applied modalities provides different images due to different physical chemistry and distribution of tracer, methods used for its detection in tissues, their sensitivity and specificity and clinical type of lymph vessel pathology. Here, the advantages and disadvantages of the most commonly used 3 methods of imaging: the iodinated oil X-ray, isotopic, and fluorescent lympangiographies are presented. The study is based on retrospective and recent collections of lymphangiograms from large cohorts of patients. Imaging of lymph nodes has not been included as it is requiring different interpretation compared with vessels. Composite evaluation of X-ray, isotopic, and fluorescent lymphographic images or, as it is practiced now the isotope and indocyanine green near infrared lymphographies, provide most clinically important information. Special attention was directed at methods enabling early diagnosis of imminent lymphedema especially in cases with cancer therapy-related lymphedema. Groups of typical images obtained with the 3 methods are presented.

Volumetric Bone Mineral Density and Failure Load of Distal Limbs Predict Incident Clinical Fracture Independent HR-pQCT BMD and Failure Load Predicts Incident Clinical Fracture of FRAX and Clinical Risk Factors Among Older Men

Our objective was to determine the associations of peripheral bone strength and microarchitecture with incident clinical and major osteoporotic fracture among older men after adjusting for major clinical risk factors. We used a prospective cohort study design with data from 1794 men (mean age 84.4 years) in the Osteoporotic Fractures in Men (MrOS) study. Eligible men attended the year 14 visit, had high-resolution peripheral quantitative computed tomography (HR-pQCT) scans of the distal radius and distal or diaphyseal tibia, DXA measured BMD, and were followed for mean 1.7 years for incident fracture. Failure load was estimated using finite element analysis. We used Cox proportional hazards models with standardized HR-pQCT parameters as exposure variables. Primary outcome was clinical fracture (n = 108). Covariates included either Fracture Risk Assessment Tool (FRAX) major osteoporotic fracture probability calculated with BMD (FRAX-BMD), or individual clinical risk factors (CRF) including age, total hip BMD, race, falls, and prevalent fracture after age 50 years. Lower failure load was associated with higher risk of incident clinical fracture and incident major osteoporotic fracture. For clinical fracture with FRAX-BMD adjustment, the associations ranged from hazard ratio (HR) 1.58 (95% CI, 1.25 to 2.01) to 2.06 (95% CI, 1.60 to 2.66) per SD lower failure load at the diaphyseal tibia and distal radius. These associations were attenuated after adjustment for individual CRFs, but remained significant at the distal sites. Associations of volumetric BMD with these outcomes were similar to those for failure load. At the distal radius, lower trabecular BMD, number, and thickness, and lower cortical BMD, thickness, and area were all associated with higher risk of clinical fracture, but cortical porosity was not. Among community-dwelling older men, HR-pQCT measures including failure load, volumetric BMD, and microstructure parameters at peripheral sites (particularly distal radius) are robust independent predictors of clinical and major osteoporotic fracture. © 2018 American Society for Bone and Mineral Research.