Detection Of Wooden Foreign Bodies Research Articles

Orbital wooden foreign body manifesting as hyperdensity on computed tomography

Detection of wooden foreign bodies within the orbit can be difficult on imaging, including computed tomography (CT). When visible, wood appears iso- or hypodense and can mimic air or fat. We report the case of a 3-year-old boy with progressive orbital cellulitis following a penetrating wood injury to the right lower lid. CT imaging revealed a linear hyperdensity contiguous with an orbital abscess. He underwent a right anterior orbitotomy with abscess drainage, during which exploration revealed a 2.3cm retained wooden foreign body. The appearance of wood as hyperdense on imaging is unusual. In the appropriate context, high clinical suspicion for retained wood should be maintained with any irregularity on CT imaging.

Improved Detection of Foreign Bodies on Radiographs Using X-ray Dark-Field and Phase-Contrast Imaging.

The aim of this study was to investigate whether the detection of foreign bodies can be improved using dark-field and phase-contrast radiography compared with conventional (transmission) radiographs. Experiments were performed using ex vivo pig paws, which were prepared with differently sized foreign bodies of metal, wood, and glass (n = 10 each). Paws without foreign bodies served as controls (n = 30). All images were acquired using an experimental grating-based large object radiography system. Five blinded readers (second- to fourth-year radiology residents) were asked to assess the presence or absence of any foreign body. Sensitivity and specificity for the detection of metal, wood, glass, and any foreign body were calculated and compared using McNemar test and generalized linear mixed models. Sensitivity for the detection of metal foreign bodies was 100% for all readers and image combinations. The sensitivity for the detection of wooden foreign bodies increased from 2% for transmission images to 78% when dark-field images were added (P < 0.0001). For glass foreign bodies, sensitivity increased from 84% for transmission images to 96% when adding phase-contrast images (P = 0.041). Sensitivity for the detection of any foreign body was 91% when transmission, dark-field, and phase-contrast images were viewed simultaneously, compared with 62% for transmission images alone (P < 0.0001). Specificity was 99% to 100% across all readers and radiography modalities. Adding dark-field images substantially improves the detection of wooden foreign bodies compared with the analysis of conventional (transmission) radiographs alone. Detection of glass foreign bodies was moderately improved when adding phase-contrast images.

The detection of wooden foreign bodies: An experimental study comparing direct digital radiography (DDR) and ultrasonography

IntroductionThis experimental study compares the appropriateness of direct digital radiography (DDR) and ultrasonography at detecting soft-tissue wooden foreign bodies (FBs) in extremities. MethodsVarying wooden FB splinters (2 mm, 5 mm and 10 mm) were inserted into eight porcine feet to simulate a patient presenting with a soft-tissue FB injury. Each of the FBs was placed in muscle distant, behind and near bone in the porcine feet. Control groups were used to check for false-positive diagnoses and, based on the presence of FBs; images were given a score depending on the level of visibility by the researcher. ResultsA higher detection rate was achieved for all FBs in muscle distant from bone using ultrasound. All of the 2 mm and 5 mm wooden FBs were not detected using DDR. The sensitivity in detecting the FBs was 5.8% and 30% in DDR and ultrasound respectively. ConclusionPoor sensitivities and specificities were identified in this study. However, this study shows that ultrasound remains superior to DDR at identifying small foreign body objects. This study demonstrates that ultrasound can be a clinically effective tool for detecting suspected wooden FBs >5 mm in the foot and thus should be considered as the primary imaging modality of choice for referring clinicians.

Diagnostic Accuracy of Emergency Bedside Ultrasonography to Detect Cutaneous Wooden Foreign Bodies: Does Size Matter?

Soft-tissue occult foreign bodies are a concerning cause of morbidity in the emergency department. The identification of wooden foreign bodies is a unique challenge because they are often not detectable by plain radiography. The purpose of this study was to determine the diagnostic accuracy of emergency physician-performed ultrasonography to detect wooden foreign bodies of varying sizes. We hypothesized that sonographic sensitivity would improve with increasing foreign body size. We conducted a blinded, prospective evaluation using a previously validated, chicken, soft-tissue model to simulate human tissue. We inserted wooden toothpicks of varying lengths (1mm, 2.5mm, 5mm, 7.5mm, 10mm) to a depth of 1cm in five tissue models. Five additional models were left without a foreign body to serve as controls. Fifty emergency physicians with prior ultrasonography training performed sonographic examinations of all 10 models and reported on the presence or absence of wooden foreign bodies. Subjects performed 10 ultrasonography examinations each for a total of 500 examinations. For the detection of wooden foreign bodies, overall test characteristics for sonography included sensitivity 48.4% (95% confidence interval [CI], 42.1%-54.8%) and specificity 67.6% (95% CI, 61.3%- 73.2%). Sensitivity did not change as object size increased (ρ = s.709). Emergency physician bedside ultrasonography demonstrated poor diagnostic accuracy for the detection of wooden foreign bodies. Accuracy did not improve with increasing object size up to 10mm. Providers should consider alternative diagnostic modalities if there is persistent clinical concern for a retained, radiolucent, soft-tissue foreign body.

RESULTS OF COMPUTED TOMOGRAPHY IN DOGS WITH SUSPECTED WOODEN FOREIGN BODIES.

Detection of wooden foreign bodies in dogs can be challenging. A retrospective, cross-sectional study was done to describe computed tomographic (CT) signs associated with wooden foreign bodies, and to estimate the accuracy of CT for detection of wooden foreign bodies. Patient records and CT images were reviewed for 72 dogs that had a history of suspected stick injury and CT of the affected body part, or possible wooden foreign object reported on CT, and had surgical exploration during the same period of hospitalization. Duration of clinical signs was acute in 48 (67%) dogs and chronic in 24 (33%). Wood was removed from 55 dogs, including a piece of a tree or shrub in 33 (60%) instances, kebab stick in 8 (15%), piece of bamboo garden cane in 2 (4%), cocktail stick in 2 (4%), thorn in 1 (2%), and unidentified wood in the remaining nine instances. Based on review of CT images with knowledge of the surgical findings, sensitivity of CT for wooden foreign bodies was 79% (95% CI 65%-89%), specificity 93% (78%-98%), positive likelihood ratio 11.5 (2.9-44.1), and negative likelihood ratio 0.23 (0.13-0.41). Wooden foreign bodies were predominantly rectangular or linear, with median length 48 mm (range 2-270 mm), median thickness 3 mm (range 1-22 mm), and median attenuation 111 HU (range -344 to +640 HU). A CT finding of gas in soft tissues was significantly associated with acute cases, whereas suspected foreign material, cavitary lesions, fat stranding, and periosteal reaction on adjacent bones were associated with chronic cases.

Wooden foreign bodies in soft tissue: role of tissue harmonic sonography

Background: Wooden foreign bodies (WFB) are usually not detectable on radiography. Ultrasound is a useful tool for detection and localization of WFB. Objectives: We evaluated the efficacy of tissue harmonic sonography in detection of WFB and describe the imaging features of WFB on tissue harmonic imaging. Methods: We retrospectively evaluated 28 patients with history of wooden (wood/thorn/bamboo) foreign body prick with tissue harmonic sonography. Results: The WFB was detected on ultrasonography in all 28 patients (100%) which was confirmed on surgery or follow up study. All WFB were echogenic casting strong posterior acoustic shadowing with or without surrounding hypoechoic halo. Conclusion: Tissue harmonic imaging is useful tool for detection and localization of retained WFB. DOI: http://dx.doi.org/10.3126/hren.v11i3.9650 Health Renaissance 2013;11(3):267-269

Rare presentation of a wooden foreign body in the thigh.

Children are prone to injury with foreign bodies, partly due to their ebullient nature. They may not always give an accurate history, which can lead to delay in diagnosis and treatment. Primary care givers need to be vigilant in eliciting a history of foreign body injury in children. Radiologists should be aware that a neglected foreign body lying close to the bone in the distal femur can evoke a massive periosteal reaction, which can mimic a bone neoplasm. Although metallic foreign bodies are detected with ease on radiographs, detection of wooden foreign bodies remains a challenging task for both the radiologist and the care-giving physician. Wood foreign bodies may induce errors in diagnosis. The paper includes an analysis of the different radiographic methods currently available and their main features. This report would be of relevance to primary care physicians, those concerned with trauma care, and for radiologists who screen for these injuries.

Ultrasound in the emergency department: detection of wooden foreign bodies in the soft tissues

Detection of a soft tissue foreign body is often very difficult, even when strongly suggested by history and physical examination. Plain radiography is helpful only in cases where the foreign body is radiopaque. Wood, which is usually radiolucent, can go undetected if further imaging is not considered. Undetected wooden foreign bodies can cause significant morbidity, repeat visits, high cost, and extensive surgery. Reported here are four cases in which ultrasound was used in the Emergency Department to detect and remove wooden foreign bodies from the soft tissues. These reports suggest that ultrasound is a clinically useful tool for the detection and removal of wooden foreign bodies by emergency physicians.

Wooden foreign bodies in soft tissue: detection at US.

To evaluate the use of ultrasound (US) for detection of wooden foreign bodies implanted in cadaveric specimens. Wooden foreign bodies were randomly placed in the plantar soft tissues of three cadaver feet by using 5-mm-long incisions. Ten foreign bodies were 2.5 x 1.0 mm (length x diameter); 10 were 5.0 x 1.0 mm. Ten incisions were performed without implantation of foreign bodies. Three musculoskeletal radiologists independently performed US in blinded fashion and recorded the presence of a foreign body. Each used 7.5- and 10-MHz linear-array transducers and was informed of the possible presence of a foreign body. Sensitivity and specificity for detection of 2.5-mm-long foreign bodies were 86.7% and 96.7%, respectively. Sensitivity and specificity for detection of 5.0-mm-long foreign bodies were 93.3% and 96.7%, respectively. Overall sensitivity was 90.0%, with specificity of 96.7%, accuracy of 92.3%, positive predictive value of 98.0%, and negative predictive value of 83.0%. US can be used effectively to locate wooden foreign bodies as small as 2.5 mm in length. Given that many foreign bodies are radiographically undetectable, the accuracy and availability of US make it an excellent modality for evaluation of radiolucent foreign bodies.

The use of ultrasonography for the detection of retained wooden foreign bodies in the foot

The efficacy of ultrasonography for the detection of wooden foreign bodies in the foot was analyzed retrospectively. Twenty patients underwent real-time, high-resolution ultrasound studies (7.5 or 10 MHz, linear array transducers) to rule out the presence of a wooden foreign body in their feet. Ten out of the 20 patients had positive ultrasound findings for a wooden foreign body. With the aid of the ultrasound study and preoperative markings, the subsequent mean surgical time was 20.8 minutes, with a 100% retrieval rate of the foreign body. Ultrasound was found to be 100% sensitive in the detection of wooden foreign bodies in the soft tissues of the foot. Ultrasonography should be considered an important diagnostic modality in the foot and ankle surgeon's armamentarium for the detection of retained wooden foreign bodies.

Detection of Wooden Foreign Bodies in Muscle Tissue: Experimental Comparison of Computed Tomography, Magnetic Resonance Imaging, and Ultrasonography

An experimental study was performed to compare computed tomography (CT), magnetic resonance imaging (MRI), and real-time, high resolution ultrasonography (US) for the detection of wooden foreign bodies in muscle tissue. Wooden splinters were prepared, measured for size, soaked in saline, and placed in porcine muscle distant from and adjacent to bone. The specimens were then examined using roentgenography, CT and MRI in planes parallel and perpendicular to the splinters, and US. The largest wooden foreign bodies (minimum smallest width = 10 mm) were easily detected by CT, MRI, and US. Almost all splinters of various sizes, small and large, soaked in saline for 5 months were easily detected by MRI. Smaller splinters (minimum smallest width = 1-4 mm) soaked for only 3 days and placed distant from bone were most easily detected by US; those soaked for 5 months were most easily detected by either US or MRI. The smaller splinters soaked for only 3 days and placed near bone were not reliably detected by any of the imaging methods; CT and MRI were both more sensitive than US in this situation. MRI scanning was more sensitive perpendicular than parallel to the long axis of the splinters. Therefore, either US or MRI may be the best initial imaging modality for evaluation of a suspected wooden foreign body, depending on availability of imaging method, chronicity of symptoms, and proximity to bone.