- Email: [email protected]
Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method
European Journal of Radiology 81 (2012) 3339–3343
Contents lists available at SciVerse ScienceDirect
European Journal of Radiology journal homepage: www.elsevier.com/locate/ejrad
Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method Kai Tao a,∗ , Sen Xu b,1 , Xiao-yan Liu a,2 , Jiu-long Liang a,3 , Tao Qiu a,4 , Jia-nan Tan a,5 , Jian-hua Che a,6 , Zi-hua Wang a,7 a b
Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016, China Department of Radiology, General Hospital of Shenyang Military Command, 83 Wenhua Steet, Shenhe District, Shenyang 110016, Liaoning Province, China
a r t i c l e
i n f o
Article history: Received 20 November 2011 Received in revised form 27 December 2011 Accepted 3 January 2012 Keywords: Foreign body Soft tissue Extraction 3-Dimensional computed tomography
a b s t r a c t Objective: To introduce a useful and accurate technique for the locating and removal of small metal foreign bodies in the soft tissues. Methods: Eight patients presented with suspected small metal foreign bodies retained in the soft tissues of various body districts. Under local anesthesia, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced through three different planes around the entry point of the foreign bodies. Using these finders, the small metal FBs were confirmed under 3D CT guidance. Based on the CT findings, the soft tissues were dissected along the path of the closest needle and the FBs were easily found and removed according to the relation with the closest needle finder. Results: Eight metal foreign bodies (3 slices, 3 nails, 1 fish hook, 1 needlepoint) were successfully removed under 3D CT guidance in all patients. The procedures took between 35 min and 50 min and the operation times took between 15 min and 25 min. No complications arose after the treatment. Conclusion: 3D CT-guided technique is a good alternative for the removal of small metal foreign body retained in the soft tissues as it is relatively accurate, reliable, quick, carries a low risk of complications and can be a first-choice procedure for the extraction of small metal foreign body. © 2012 Elsevier Ireland Ltd. All rights reserved.
Injury resulting from foreign bodies (FBs) is one of the most common injury types in the hand, foot, knee, and elbow [1,2]. Detection and management of foreign materials in soft tissues is a common problem in the emergency department. There are many techniques available for finding them, but the exact position of a small object buried in soft tissue is still difficult to determine using two-dimensional imaging techniques. In this report we describe a new, reliable technique which uses 3D CT guidance for detection of small, superficial, metal FBs.
∗ Corresponding author at: Dept. of Plastic Surgery, General Hospital of Shenyang Military Command 83 Wenhua Steet, Shenhe District, Shenyang 110016, Liaoning Province, China. Tel.: +86 24 28851311/16/13309887570; fax: +86 24 23880136. E-mail addresses: [email protected] (K. Tao), [email protected] (S. Xu), [email protected] (X.-y. Liu), [email protected] (J.-l. Liang), [email protected] (T. Qiu), [email protected] (J.-n. Tan), [email protected] (J.-h. Che), [email protected] (Z.-h. Wang). 1 Tel.: +86 24 28851452; fax: +86 13804982084. 2 Tel.: +86 24 28856250/13309888802; fax: +86 24 23880136. 3 Tel.: +86 24 28851311; fax: +86 15309882760. 4 Tel.: +86 24 28851311; fax: +86 13309885736. 5 Tel.: +86 24 28851311; fax: +86 18909882599. 6 Tel.: +86 24 28851311; fax: +86 15309880774. 7 Tel.: +86 24 28851311; fax: +86 18909882043. 0720-048X/$ – see front matter © 2012 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrad.2012.01.002
1. Patients and methods Eight patients with soft tissue foreign bodies were treated in our department between January and August 2011. They were seven men and one woman aged 25–63 years (mean age 41 years). The metal FBs were 3 slices, 3 nails, 1 fish hook and 1 needle tip. Small metal foreign bodies were retained in the soft tissues of various body districts including 6 palms, 1 forearm and 1 buttock. The pretherapeutic times were from 1.5 h to 2 w. Three patients presented to our department complaining of persistent foreign body sensation. Five patients had no abnormal sensation (see Table 1).
1.1. Treatment protocol The first part of the intervention was plain radiography to confirm the diagnosis of a metal FB. The subcutaneous or muscular local anesthesia were made by 0.75% bupivacaine. For the cases with visible entrances of the FB, short incisions of about 1.5 cm were made and the soft tissue was dissected for the detection of the FB. In this way, some FBs may be found if the location is not very deep and just under the entrance (we had three such cases, which were not included in this case report). If the FB was not detected easily, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced
3340
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
Table 1 Patient demographic and clinical data. Patient
Gender
Age
FB character
Site
Pretherapeutic time
Symptom
FB size (mm)
Locating layer
Therapeutic time (min)
Operative time (min)
1 2 3 4 5 6 7 8
Male Female Male Male Male Male Male Male
39 63 50 36 46 38 31 25
Slice Needle tip Fish hook Slice Nail Nail Nail Slice
Forearm Buttock Palm Palm Palm Palm Palm Palm
1h 2w 3d 2h 1.5 h 2h 4h 4h
None None None None Foreign body sensation Foreign body sensation None Foreign body sensation
3×3 5 × 0.5 2 × 0.5 6×5 4×2 4×2 5×1 5×4
Intramuscular Subcutaneous Subcutaneous Intramuscular Intramuscular Subcutaneous Intramuscular Intramuscular
50 45 50 45 55 40 40 40
25 20 20 15 25 20 20 20
through three different planes around the entry point of the FBs. The first and second needles were inserted in the direction tangential to the body surface and were perpendicular to each other. They were inserted deeply enough to bury the needle totally. The other needles were inserted in the direction perpendicular to the body surface and they aligned with an interval of 5 mm. In one case, 3 needles were enough. In two cases, 4 needles were enough. The injury sites were bandaged with sterile dressing. With these needle finders in place, the patients underwent the CT examination. The multiplane reconstruction (GE Medical Systems LightSpeed VCT 64 with an ADW 4.4 workstation) enabled the position of the needles and FBs to be visualized in different planes and the most direct distance to the skin to be estimated, as well as the closest needle to be determined. The 3D CT images provided accurate positioning of the metal FBs relative to the needle finders. The depth, length and direction of the FBs were also determined. After the CT examination, patients returned to the operation room. Based on the CT findings, an incision was made superficial to the foreign body and adjacent to the closest needle. After the incision, the FBs were easily found and removed according to their relation to the closest needle finder. Following the removal of the FBs, the wounds were thoroughly irrigated and carefully debrided, then they were primarily closed. Tetanus prophylaxis was prescribed to all patients and antibiotic prophylaxis with cefoperazone (3 g, IV, Bid) was also prescribed for 5 days after the procedure. 2. Results The FBs, 2–6 mm in length and 0.5–5 mm in width or in diameter, were extracted successfully in all cases. The locating layers were 3 subcutaneous planes and 5 intramuscular planes. The mean therapeutic time was 45 min (range from 40 to 55 min) and the mean operative time was 20 min (range from 15 to 25 min). All postoperative courses were uneventful and the wound healed without complications in all cases. All patients showed great satisfaction with the results (see Table 1). 3. Case reports 3.1. Case one A 63-year-old woman presented to the plastic surgery department complaining of a retained tip of insulin-injection needle in her right buttock. She had a history of diabetes and insulin injection for about 5 years. Two weeks before, the injection needle severed and left a small part of itself in her buttock. Although she had no symptoms, she felt a psychological burden and demanded the removal of the needle tip. Before she came to our hospital, she had been refused by many others. Physical examination revealed no wound on the buttock and the patient only remembered the injection point approximately. After the usual preparation, the 3D CT-guidance method was used. The metal needle tip was removed within 45 min.
The needle tip was 5 mm in length and 0.5 mm in diameter. The distance between the remembered injection point and the actual incision point was 2 cm (see Fig. 1 of the case 1). 3.2. Case two A 50-year-old man presented to the plastic surgery department complaining of a retained fish hook in his left palm. Three days before, a fish hook stuck accidentally while he was fishing. Physical examination revealed a 2 mm entrance wound in the left minor thenar region. Although without symptoms, he wanted the small part of fish hook removed. Once again, CT-guidance method was used. When detecting the FB, because the object was very small and was in superposition with the needle image, the FB could not be seen at first. After using multiple planes of observation, a very small, abnormal image was finally found. The fish hook was removed within 50 min. It was 2 mm in length and 0.5 mm in diameter (see Fig. 2). 4. Discussion Foreign bodies embedded in soft tissue can cause toxic and allergic reactions, inflammation, or infection. The extraction procedure is not a large operation but sometimes can be difficult and time consuming [3–5]. Although focused history questions and physical examination may provide clues to the presence of a retained FB, its presence may not always be obvious. Detecting the presence of a foreign body in soft tissue is easier than locating its exact position. Before exploring tissue, the clinician should identify a point on the skin directly over the foreign body and estimate the depth of the object in the tissues; otherwise potential damage to the surrounding tissues may occur under blind and unplanned exploration. Plain radiography, computed tomography, and ultrasonography can be used to detect FBs embedded in soft tissue [6–8], but for a small FB, the exact position is difficult to determine using two-dimensional imaging techniques. The common method is the following: based on the image finding, the incision is made surrounding the entrance of the FB. The soft tissue is separated from the superficial tissue deep enough for detection. Because the size, configuration and orientation of FBs are not clear, however, the exploring course is usually blind or can become a dilemma which can afflict both patient and clinician. Therefore some clinicians make the choice to refuse the treatment. The patient of case one with the severed needle tip in her right buttock is an example of this. Although without any symptoms, she had the psychological burden and demanded the removal of the FB. After being refused by many hospitals, she came to our hospital. Another common location methods is the following: two or three needles are angled at 90◦ to each other, radiographs are used to identify the needle closest to the FB. The tissue is then dissected along the path of the closest needle [9]. This two-dimensional method is usually not enough for the location of the small FB and the detection procedure is still not under control. Ultrasonography has
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
3341
Fig. 1. A 63-year-old woman with a retained tip of insulin-injection needle in her right buttock. (a) and (b) Based on the remembered injection points (with the “ × ” label), four needles were inserted into the buttock. (c) and (d) The 3D CT reconstructed images revealed the position of the FB. It was in the subcutaneous plane and the distances between the foreign body and the skin surface was 19.6 mm. And it was closed to the tip of one of the needles with the distance of 8.2 mm. (e)–(g): Based on the 3D CT images, the metal needle tip was detected and removed, which was 5 mm in length and 0.5 mm in diameter. The distance between the remembered injection point and the actual incision point was 2 cm.
been used with variable success to locate soft tissue foreign bodies [10,11]. Successful imaging of sound echoes depends on the size, shape, orientation, and composition of the object. Therefore the small object may be confused with an echo artifact. Furthermore, an experienced examiner and a technically reliable transducer are essential [12].
We report on a simple and reliable technique for small metal FB extraction. After inserting needle finders in three planes, the multiplane reconstruction of a CT scan provide a three-dimensional picture that allows localization and identification of the FB. As a result of the accurate localization, the procedure becomes very simple and quick. The total therapeutic time is less than 1 h and the real
3342
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
Fig. 2. A 50-year-old man with a retained fish hook in his left palm. (a) A 2 cm incision was made over the left palm. (b) Five needles were inserted after failing to detect the foreign body. (c) and (d) The 3D CT reconstructed images revealed the position of the FB. It was in the subcutaneous plane. At first, the small object’s image was in the superposition with that of the needle. After the multiple planes observation it was found just closed to one of the needles, which was perpendicular to surface. (e) The fish hook was 2 mm in length and 0.5 mm in diameter.
operative time is less than half an hour. Another advantage is the minimal damage and rapid recovery time. Here are some details for this technique: at least three needle finders, angled at 90◦ to each other, are necessary. The needle number should be increased if the body surface is large, such as the buttock. A 5 ml syringe needle is commonly be used as the finder while sometimes 1 ml syringe needles can also be used, especially as the finder perpendicular to the body surface. During the course
of detecting and observing FB, a very small object’s image may be in superposition with that of the needle. In that case, the multiple planes observation is necessary (see case two). Because different tissue has different radiodensity, with the volume rendering technique the presence layer of the FB can be determined by adjusting the window and level of the image. Once the FB is located, the tissue is dissected along the path of the most adjacent needle and down to the corresponding layer. As a result, during the course of returning
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
to the operating room and opening the dressing, more attention should be paid to ensure the needles’ position remains unchanged. 5. Conclusion Due to its relative accuracy, reliability, operating and recovery speed and low risk of complications, 3D CT-guided technique is a good alternative for the removal of small metal FBs retained in the soft tissues and should be considered a first-choice procedure. Conflict of interest The authors have no financial interest to declare in relation to the content of this article. References [1] Anderson MA, Newmeyer WL, Kilgore ES. Diagnosis and treatment of retained foreign bodies in the hand. Am J Surg 1982;144(1):63–7.
3343
[2] Donaldson. Radiographic imaging of foreign bodies in the hand. Hand Clin 1991;7(1):125–34. [3] Chisholm CD, Wood CO, Chua G, et al. Radiographic detection of gravel in soft tissue. Ann Emerg Med 1997;29(6):725–30. [4] Turner J, Wilde CH, Hughes KC, et al. Ultrasound-guided retrieval of small foreign objects in subcutaneous tissue. Ann Emerg Mel 1997;29(6):731–4. [5] Lammers RL. Soft tissue foreign bodies. Ann Emerg Med 1988;17(12):1336–47. [6] Ginsburg MJ, Ellis GL, Flom LL, et al. Detection of soft-tissue foreign bodies by plain radiography, Xerography, computed tomography, and ultrasonography. Ann Emerg Med 1990;19(6):701–3. [7] De Flaviis L, Scaglione P, Del Bo P, et al. Detection of foreign bodies in soft tissues: experimental comparison of ultrasonography and xeroradiography. J Trauma 1988;28(3):400–4. [8] Amoretti N, Hauger O, Marcy PY, et al. Foreign body extraction from soft tissue by using CT and fluoroscopic guidance: a new technique. Eur Radiol 2010;20(2):190–2. [9] Rickoff SE, Bauder T, Kerman BL. Foreign body localization and retrieval in the foot. J Foot Surg 1981;20(1):33–4. [10] Levsky ME, McArthur T, Abell BA, et al. A procedure for soft tissue foreign body removal under real-time ultrasound guidance. Military Med 2007;172(8):858–9. [11] Dean AJ, Gronczewski CA, Costantino TG. Technique for emergency medicine bedside ultrasound identification of a radiolucent foreign body. J Emerg Med 2003;24(3):303–8. [12] Manthey DE, Storrow AB, Milbourn JM, et al. Ultrasound versus radiography in the detection of soft-tissue foreign bodies. Ann Emerg Med 1996;28(7):7–9.
Contents lists available at SciVerse ScienceDirect
European Journal of Radiology journal homepage: www.elsevier.com/locate/ejrad
Small metal soft tissue foreign body extraction by using 3D CT guidance: A reliable method Kai Tao a,∗ , Sen Xu b,1 , Xiao-yan Liu a,2 , Jiu-long Liang a,3 , Tao Qiu a,4 , Jia-nan Tan a,5 , Jian-hua Che a,6 , Zi-hua Wang a,7 a b
Department of Plastic Surgery, General Hospital of Shenyang Military Command, PLA, Shenyang 110016, China Department of Radiology, General Hospital of Shenyang Military Command, 83 Wenhua Steet, Shenhe District, Shenyang 110016, Liaoning Province, China
a r t i c l e
i n f o
Article history: Received 20 November 2011 Received in revised form 27 December 2011 Accepted 3 January 2012 Keywords: Foreign body Soft tissue Extraction 3-Dimensional computed tomography
a b s t r a c t Objective: To introduce a useful and accurate technique for the locating and removal of small metal foreign bodies in the soft tissues. Methods: Eight patients presented with suspected small metal foreign bodies retained in the soft tissues of various body districts. Under local anesthesia, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced through three different planes around the entry point of the foreign bodies. Using these finders, the small metal FBs were confirmed under 3D CT guidance. Based on the CT findings, the soft tissues were dissected along the path of the closest needle and the FBs were easily found and removed according to the relation with the closest needle finder. Results: Eight metal foreign bodies (3 slices, 3 nails, 1 fish hook, 1 needlepoint) were successfully removed under 3D CT guidance in all patients. The procedures took between 35 min and 50 min and the operation times took between 15 min and 25 min. No complications arose after the treatment. Conclusion: 3D CT-guided technique is a good alternative for the removal of small metal foreign body retained in the soft tissues as it is relatively accurate, reliable, quick, carries a low risk of complications and can be a first-choice procedure for the extraction of small metal foreign body. © 2012 Elsevier Ireland Ltd. All rights reserved.
Injury resulting from foreign bodies (FBs) is one of the most common injury types in the hand, foot, knee, and elbow [1,2]. Detection and management of foreign materials in soft tissues is a common problem in the emergency department. There are many techniques available for finding them, but the exact position of a small object buried in soft tissue is still difficult to determine using two-dimensional imaging techniques. In this report we describe a new, reliable technique which uses 3D CT guidance for detection of small, superficial, metal FBs.
∗ Corresponding author at: Dept. of Plastic Surgery, General Hospital of Shenyang Military Command 83 Wenhua Steet, Shenhe District, Shenyang 110016, Liaoning Province, China. Tel.: +86 24 28851311/16/13309887570; fax: +86 24 23880136. E-mail addresses: [email protected] (K. Tao), [email protected] (S. Xu), [email protected] (X.-y. Liu), [email protected] (J.-l. Liang), [email protected] (T. Qiu), [email protected] (J.-n. Tan), [email protected] (J.-h. Che), [email protected] (Z.-h. Wang). 1 Tel.: +86 24 28851452; fax: +86 13804982084. 2 Tel.: +86 24 28856250/13309888802; fax: +86 24 23880136. 3 Tel.: +86 24 28851311; fax: +86 15309882760. 4 Tel.: +86 24 28851311; fax: +86 13309885736. 5 Tel.: +86 24 28851311; fax: +86 18909882599. 6 Tel.: +86 24 28851311; fax: +86 15309880774. 7 Tel.: +86 24 28851311; fax: +86 18909882043. 0720-048X/$ – see front matter © 2012 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.ejrad.2012.01.002
1. Patients and methods Eight patients with soft tissue foreign bodies were treated in our department between January and August 2011. They were seven men and one woman aged 25–63 years (mean age 41 years). The metal FBs were 3 slices, 3 nails, 1 fish hook and 1 needle tip. Small metal foreign bodies were retained in the soft tissues of various body districts including 6 palms, 1 forearm and 1 buttock. The pretherapeutic times were from 1.5 h to 2 w. Three patients presented to our department complaining of persistent foreign body sensation. Five patients had no abnormal sensation (see Table 1).
1.1. Treatment protocol The first part of the intervention was plain radiography to confirm the diagnosis of a metal FB. The subcutaneous or muscular local anesthesia were made by 0.75% bupivacaine. For the cases with visible entrances of the FB, short incisions of about 1.5 cm were made and the soft tissue was dissected for the detection of the FB. In this way, some FBs may be found if the location is not very deep and just under the entrance (we had three such cases, which were not included in this case report). If the FB was not detected easily, 3–6 pieces of 5 ml syringe needles or 1 ml syringe needles were induced
3340
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
Table 1 Patient demographic and clinical data. Patient
Gender
Age
FB character
Site
Pretherapeutic time
Symptom
FB size (mm)
Locating layer
Therapeutic time (min)
Operative time (min)
1 2 3 4 5 6 7 8
Male Female Male Male Male Male Male Male
39 63 50 36 46 38 31 25
Slice Needle tip Fish hook Slice Nail Nail Nail Slice
Forearm Buttock Palm Palm Palm Palm Palm Palm
1h 2w 3d 2h 1.5 h 2h 4h 4h
None None None None Foreign body sensation Foreign body sensation None Foreign body sensation
3×3 5 × 0.5 2 × 0.5 6×5 4×2 4×2 5×1 5×4
Intramuscular Subcutaneous Subcutaneous Intramuscular Intramuscular Subcutaneous Intramuscular Intramuscular
50 45 50 45 55 40 40 40
25 20 20 15 25 20 20 20
through three different planes around the entry point of the FBs. The first and second needles were inserted in the direction tangential to the body surface and were perpendicular to each other. They were inserted deeply enough to bury the needle totally. The other needles were inserted in the direction perpendicular to the body surface and they aligned with an interval of 5 mm. In one case, 3 needles were enough. In two cases, 4 needles were enough. The injury sites were bandaged with sterile dressing. With these needle finders in place, the patients underwent the CT examination. The multiplane reconstruction (GE Medical Systems LightSpeed VCT 64 with an ADW 4.4 workstation) enabled the position of the needles and FBs to be visualized in different planes and the most direct distance to the skin to be estimated, as well as the closest needle to be determined. The 3D CT images provided accurate positioning of the metal FBs relative to the needle finders. The depth, length and direction of the FBs were also determined. After the CT examination, patients returned to the operation room. Based on the CT findings, an incision was made superficial to the foreign body and adjacent to the closest needle. After the incision, the FBs were easily found and removed according to their relation to the closest needle finder. Following the removal of the FBs, the wounds were thoroughly irrigated and carefully debrided, then they were primarily closed. Tetanus prophylaxis was prescribed to all patients and antibiotic prophylaxis with cefoperazone (3 g, IV, Bid) was also prescribed for 5 days after the procedure. 2. Results The FBs, 2–6 mm in length and 0.5–5 mm in width or in diameter, were extracted successfully in all cases. The locating layers were 3 subcutaneous planes and 5 intramuscular planes. The mean therapeutic time was 45 min (range from 40 to 55 min) and the mean operative time was 20 min (range from 15 to 25 min). All postoperative courses were uneventful and the wound healed without complications in all cases. All patients showed great satisfaction with the results (see Table 1). 3. Case reports 3.1. Case one A 63-year-old woman presented to the plastic surgery department complaining of a retained tip of insulin-injection needle in her right buttock. She had a history of diabetes and insulin injection for about 5 years. Two weeks before, the injection needle severed and left a small part of itself in her buttock. Although she had no symptoms, she felt a psychological burden and demanded the removal of the needle tip. Before she came to our hospital, she had been refused by many others. Physical examination revealed no wound on the buttock and the patient only remembered the injection point approximately. After the usual preparation, the 3D CT-guidance method was used. The metal needle tip was removed within 45 min.
The needle tip was 5 mm in length and 0.5 mm in diameter. The distance between the remembered injection point and the actual incision point was 2 cm (see Fig. 1 of the case 1). 3.2. Case two A 50-year-old man presented to the plastic surgery department complaining of a retained fish hook in his left palm. Three days before, a fish hook stuck accidentally while he was fishing. Physical examination revealed a 2 mm entrance wound in the left minor thenar region. Although without symptoms, he wanted the small part of fish hook removed. Once again, CT-guidance method was used. When detecting the FB, because the object was very small and was in superposition with the needle image, the FB could not be seen at first. After using multiple planes of observation, a very small, abnormal image was finally found. The fish hook was removed within 50 min. It was 2 mm in length and 0.5 mm in diameter (see Fig. 2). 4. Discussion Foreign bodies embedded in soft tissue can cause toxic and allergic reactions, inflammation, or infection. The extraction procedure is not a large operation but sometimes can be difficult and time consuming [3–5]. Although focused history questions and physical examination may provide clues to the presence of a retained FB, its presence may not always be obvious. Detecting the presence of a foreign body in soft tissue is easier than locating its exact position. Before exploring tissue, the clinician should identify a point on the skin directly over the foreign body and estimate the depth of the object in the tissues; otherwise potential damage to the surrounding tissues may occur under blind and unplanned exploration. Plain radiography, computed tomography, and ultrasonography can be used to detect FBs embedded in soft tissue [6–8], but for a small FB, the exact position is difficult to determine using two-dimensional imaging techniques. The common method is the following: based on the image finding, the incision is made surrounding the entrance of the FB. The soft tissue is separated from the superficial tissue deep enough for detection. Because the size, configuration and orientation of FBs are not clear, however, the exploring course is usually blind or can become a dilemma which can afflict both patient and clinician. Therefore some clinicians make the choice to refuse the treatment. The patient of case one with the severed needle tip in her right buttock is an example of this. Although without any symptoms, she had the psychological burden and demanded the removal of the FB. After being refused by many hospitals, she came to our hospital. Another common location methods is the following: two or three needles are angled at 90◦ to each other, radiographs are used to identify the needle closest to the FB. The tissue is then dissected along the path of the closest needle [9]. This two-dimensional method is usually not enough for the location of the small FB and the detection procedure is still not under control. Ultrasonography has
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
3341
Fig. 1. A 63-year-old woman with a retained tip of insulin-injection needle in her right buttock. (a) and (b) Based on the remembered injection points (with the “ × ” label), four needles were inserted into the buttock. (c) and (d) The 3D CT reconstructed images revealed the position of the FB. It was in the subcutaneous plane and the distances between the foreign body and the skin surface was 19.6 mm. And it was closed to the tip of one of the needles with the distance of 8.2 mm. (e)–(g): Based on the 3D CT images, the metal needle tip was detected and removed, which was 5 mm in length and 0.5 mm in diameter. The distance between the remembered injection point and the actual incision point was 2 cm.
been used with variable success to locate soft tissue foreign bodies [10,11]. Successful imaging of sound echoes depends on the size, shape, orientation, and composition of the object. Therefore the small object may be confused with an echo artifact. Furthermore, an experienced examiner and a technically reliable transducer are essential [12].
We report on a simple and reliable technique for small metal FB extraction. After inserting needle finders in three planes, the multiplane reconstruction of a CT scan provide a three-dimensional picture that allows localization and identification of the FB. As a result of the accurate localization, the procedure becomes very simple and quick. The total therapeutic time is less than 1 h and the real
3342
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
Fig. 2. A 50-year-old man with a retained fish hook in his left palm. (a) A 2 cm incision was made over the left palm. (b) Five needles were inserted after failing to detect the foreign body. (c) and (d) The 3D CT reconstructed images revealed the position of the FB. It was in the subcutaneous plane. At first, the small object’s image was in the superposition with that of the needle. After the multiple planes observation it was found just closed to one of the needles, which was perpendicular to surface. (e) The fish hook was 2 mm in length and 0.5 mm in diameter.
operative time is less than half an hour. Another advantage is the minimal damage and rapid recovery time. Here are some details for this technique: at least three needle finders, angled at 90◦ to each other, are necessary. The needle number should be increased if the body surface is large, such as the buttock. A 5 ml syringe needle is commonly be used as the finder while sometimes 1 ml syringe needles can also be used, especially as the finder perpendicular to the body surface. During the course
of detecting and observing FB, a very small object’s image may be in superposition with that of the needle. In that case, the multiple planes observation is necessary (see case two). Because different tissue has different radiodensity, with the volume rendering technique the presence layer of the FB can be determined by adjusting the window and level of the image. Once the FB is located, the tissue is dissected along the path of the most adjacent needle and down to the corresponding layer. As a result, during the course of returning
K. Tao et al. / European Journal of Radiology 81 (2012) 3339–3343
to the operating room and opening the dressing, more attention should be paid to ensure the needles’ position remains unchanged. 5. Conclusion Due to its relative accuracy, reliability, operating and recovery speed and low risk of complications, 3D CT-guided technique is a good alternative for the removal of small metal FBs retained in the soft tissues and should be considered a first-choice procedure. Conflict of interest The authors have no financial interest to declare in relation to the content of this article. References [1] Anderson MA, Newmeyer WL, Kilgore ES. Diagnosis and treatment of retained foreign bodies in the hand. Am J Surg 1982;144(1):63–7.
3343
[2] Donaldson. Radiographic imaging of foreign bodies in the hand. Hand Clin 1991;7(1):125–34. [3] Chisholm CD, Wood CO, Chua G, et al. Radiographic detection of gravel in soft tissue. Ann Emerg Med 1997;29(6):725–30. [4] Turner J, Wilde CH, Hughes KC, et al. Ultrasound-guided retrieval of small foreign objects in subcutaneous tissue. Ann Emerg Mel 1997;29(6):731–4. [5] Lammers RL. Soft tissue foreign bodies. Ann Emerg Med 1988;17(12):1336–47. [6] Ginsburg MJ, Ellis GL, Flom LL, et al. Detection of soft-tissue foreign bodies by plain radiography, Xerography, computed tomography, and ultrasonography. Ann Emerg Med 1990;19(6):701–3. [7] De Flaviis L, Scaglione P, Del Bo P, et al. Detection of foreign bodies in soft tissues: experimental comparison of ultrasonography and xeroradiography. J Trauma 1988;28(3):400–4. [8] Amoretti N, Hauger O, Marcy PY, et al. Foreign body extraction from soft tissue by using CT and fluoroscopic guidance: a new technique. Eur Radiol 2010;20(2):190–2. [9] Rickoff SE, Bauder T, Kerman BL. Foreign body localization and retrieval in the foot. J Foot Surg 1981;20(1):33–4. [10] Levsky ME, McArthur T, Abell BA, et al. A procedure for soft tissue foreign body removal under real-time ultrasound guidance. Military Med 2007;172(8):858–9. [11] Dean AJ, Gronczewski CA, Costantino TG. Technique for emergency medicine bedside ultrasound identification of a radiolucent foreign body. J Emerg Med 2003;24(3):303–8. [12] Manthey DE, Storrow AB, Milbourn JM, et al. Ultrasound versus radiography in the detection of soft-tissue foreign bodies. Ann Emerg Med 1996;28(7):7–9.