Multitechnique Imaging Findings of Prolene Plug Hernia Repair

Transcription

1 Genitourinary Imaging Pictorial Essay Cronin et al. Imaging of Prolene Plug Hernia Repair Genitourinary Imaging Pictorial Essay Carmel G. Cronin 1 Mukesh G. Harisinghani Onofrio Catalano Michael. lake Cronin CG, Harisinghani MG, Catalano O, lake M Keywords: inguinal hernia, polypropylene, Prolene plug repair system, Prolene plugs DOI: /JR Received December 17, 2009; accepted after revision February 11, ll authors: Department of bdominal Imaging and Interventional Radiology, Massachusetts General Hospital and Harvard Medical School, White 270, 55 Fruit St., oston, M ddress correspondence to C. G. Cronin. JR 2010; 195: X/10/ merican Roentgen Ray Society Multitechnique Imaging Findings of Prolene Plug Hernia Repair OJECTIVE. The objective of this article is to illustrate the spectrum of imaging findings of polypropylene (Prolene) plug hernia repair. CONCLUSION. Knowledge of patient history and awareness of postsurgical imaging appearances are of importance because Prolene plugs are often incidentally encountered and if misdiagnosed may lead to erroneous patient disease staging and management. I nguinal hernias are very common. The lifetime risk of developing an inguinal hernia is 27% for men and 3% for women [1]. Patient symptoms, such as groin fullness and pain, and complications including bowel obstruction and incarceration are not rare. Their significant morbidity and possible mortality have resulted in patients frequently undergoing repair, making herniorrhaphy one of the most common surgical operations. Mesh systems used at inguinal hernia repair as well as for other abdominal wall hernias are now well recognized as linear 1-mmthick high-density foreign bodies at the site of repair [2]. newer mechanism of hernia repair includes filling the hernial orifice with a nonabsorbable material such as a polypropylene (Prolene, ard) plug to reinforce the defect [3]. The Prolene mesh plug is placed into inguinal hernia defects, and flat mesh is used to cover the defect [4] (Fig. 1). The plug is readily and often seen on cross-sectional imaging; however, its typical appearance has been described infrequently [2, 4]. Identification of the normal postsurgical appearance at ultrasound, CT, PET/CT, and MRI is essential to avoid misdiagnosis. Knowledge of patient history and identification of an inguinal surgical scar may be helpful in the diagnosis. wareness of the postsurgical imaging appearance is of importance because Prolene plugs are often incidentally encountered. In addition, pertinent surgical history is not usually highlighted and is sometimes unavailable and, if misinterpreted, may lead to erroneous patient disease staging, intervention, and management. Imaging Findings Prolene plugs are not routinely appreciated at radiography. t ultrasound, Prolene plugs appear as hyperechoic lines with distal shadowing [2] (Fig. 2). On cross-sectional imaging (ultrasound, CT, and MRI), Prolene plugs appear as focal masses that may be unilateral or bilateral (Fig. 3). They may be small or large depending on the size requirement at surgery and have a mean long-axis diameter up to 2.6 cm [3] (Figs. 4 and 5). t CT, Prolene plugs have a slightly nodular or smooth outline (Figs. 4 6). The density is similar to (Fig. 4) or slightly lower than (Fig. 5) the adjacent muscle. Occasionally two distinct plugs may be seen if multiple or recurrent hernia defects are being repaired (Fig. 5). They are usually located anterior to the iliac vessels at the inguinal canal. Prolene plugs have been reported to appear as a ringlike density with central fat attenuation (Figs. 6 and 7] and a rim of higher attenuation in up to 39% of repairs [4]. When this appearance is seen in a left-sided inguinal hernia repair that abuts the sigmoid colon, it can potentially mimic epiploic appendagitis [4]. When the plugs are of soft-tissue density, they may simulate an area of fat necrosis or an inflamed diverticulum (Fig. 8). ir may be seen within the plug, which may represent postoperative change if within the postoperative period in the presence of local inflammation or infection in the correct clinical setting (Fig. 9). The location of Prolene plugs in the inguinal regions and their soft-tissue density may lead to their being misdiagnosed by the unwary as lymphadenopathy [4] (Figs. 10 and 11). This JR:195, September

2 Cronin et al. imaging similarity may result in unnecessary interventions, including radiologic or surgical biopsy to provide a tissue diagnosis, or may result in erroneous diagnoses of lymphomatous disease or false upstaging of disease. The appearance of Prolene plugs has not been described at PET/CT. The CT features are similar to those already described at CT. The PET features vary from showing no significant 18 F-FDG uptake (Fig. 12) to increased FDG uptake (Fig. 13). Without the correct clinical history of a Prolene plug hernia repair, moderate to intensely avid uptake may be misdiagnosed as lymphomatous disease and patient disease erroneously upstaged and treated (Fig. 13). The appearance of Prolene plugs has not yet been described at MRI. In our experience, Prolene plugs appear to have a low signal on T1-weighted and low to intermediate or slightly high signal on T2-weighted images relative to the adjacent musculature (Figs. 14 and 15). The periphery or majority of the Prolene plug may enhance (Figs. 14 and 15). The presence of a herniorrhaphy scar and susceptibility artifact and surgical clips indicate surgery as the cause (Fig. 15). gain, Fig. 1 Photograph shows polypropylene mesh plug and sheet. Mesh plug is placed into inguinal hernia defects, and flat mesh is used to cover defect. this finding may pose similar clinical dilemmas if not correctly identified. Complications The recurrence rate after primary inguinal hernia repair is 4% and for repair of recurrent inguinal hernia is 11% [5]. Other complications associated with Prolene plugs include postoperative seromas (Figs. 9, 11, and 16), mesh infection [6] (Fig. 7), plug migration (Fig. 16), bowel injury with small-bowel obstruction [7], recurrent herniation, and testicular atrophy [8]. Conclusion Knowledge of patient history and awareness of the expected postsurgical imaging appearance is of importance because Prolene plugs are often incidentally encountered and if unrecognized by radiologists may lead to erroneous patient disease staging and management. References 1. Jenkins JT, O Dwyer PJ. Inguinal hernias. MJ 2008; 336: Parra J, Revuelta S, Gallego T, et al. Prosthetic mesh used for inguinal and ventral hernia repair: Fig year-old woman with atypical lymphocytes raising possibility of lymphoma. This patient was found to have soft-tissue-density mass in left inguinal region. History of distant hernia repair was unknown, and mass was biopsied. Lesion later was diagnosed correctly as polypropylene (Prolene, ard) plug. Ultrasound image obtained at time of needle biopsy shows characteristic appearance of Prolene plugs at ultrasound that of hyperechoic lines with distal shadowing (arrow). normal appearance and complications in ultrasound and CT. r J Radiol 2004; 77: llan SM, Heddle RM. Prolene plug repair for femoral hernia. nn R Coll Surg Engl 1989; 71: Yeung VH, Pearl JM, Coakley FV, Joe N, Westphalen C, Yeh M. Computed tomographic appearance of Prolene Hernia System and polypropylene mesh plug inguinal hernia repair. J Comput ssist Tomogr 2008; 32: Staarink M, van Veen RN, Hop WC, Weidema WF. 10-year follow-up study on endoscopic total extraperitoneal repair of primary and recurrent inguinal hernia. Surg Endosc 2008; 22: Hasegawa S, Yoshikawa T, Yamamoto Y, et al. Long-term outcome after hernia repair with the Prolene hernia system. Surg Today 2006; 36: Lo DJ, ilimoria KY, Pugh CM. owel complications after Prolene hernia system (PHS) repair: a case report and review of the literature. Hernia 2008; 12: Faraj D, Ruurda JP, Olsman JG, van Geffen HJ. Five-year results of inguinal hernia treatment with the Prolene Hernia System in a regional training hospital. Hernia 2010; 14: JR:195, September 2010

3 Imaging of Prolene Plug Hernia Repair Fig. 3 Polypropylene (Prolene, ard) plugs., 45-year-old man with right-sided unilateral Prolene plug (arrow)., 50-year-old man with left-sided unilateral Prolene plug (arrow). C, 40-year-old man with bilateral Prolene plugs (arrows). Fig year-old man who underwent CT for upper abdominal pain. Image shows incidental small cm polypropylene (Prolene, ard) plugs bilaterally (arrows). Fig year-old man after hernia repair. CT image shows bilateral polypropylene (Prolene, ard) plugs (arrows) to reinforce large hernial defects. C Fig year-old man with history of lung cancer who underwent staging CT that shows polypropylene (Prolene, ard) plug with fat peripherally (arrow). Fig year-old man with bilateral polypropylene (Prolene, ard) plugs (black arrows). Postoperative seroma (curved arrow) around and anterior to right Prolene plug gradually resolved on follow-up imaging. Eccentric fat is seen within left Prolene plug (straight white arrow). JR:195, September

4 Cronin et al. Fig year-old man who underwent CT for evaluation of lymphoma. Location of polypropylene (Prolene, ard) plugs in inguinal regions and their soft-tissue or lower density may be misdiagnosed by unwary as lymphadenopathy. This patient has not undergone hernia repair, and lymphadenopathy is identified in inguinal regions (white and black arrows). Lymphadenopathy (white arrows) may have similar appearance to Prolene plugs in their location anteromedial to iliac vessels. Further lymph nodes also are seen alerting to correct diagnosis of lymphoma (black arrows). Fig year-old man who underwent CT for assessment of abdominal pain. and, Patient was found to have diverticulosis and low-density nodular soft-tissue lesion inseparable from sigmoid colon, indistinguishable from inflamed diverticulum with surrounding fat stranding or fat necrosis (arrow). However, correct diagnosis of polypropylene (Prolene, ard) plug was made on further review of history. Fig year-old man after repair of incarcerated right inguinal hernia., ir (black arrow) is seen within polypropylene (Prolene, ard) plug (straight white arrow), which in presence of local inflammation and subcutaneous air and seroma (curved arrow) may represent postoperative findings or infection in correct clinical setting., In this case, the findings represented postsurgical changes and resolved on follow-up imaging. rrow = prolene plug. Fig year-old man under evaluation for fevers and weight loss. Within abdomen, solitary soft-tissue mass was seen anterior to left iliac vessels. Its appearance is similar to that of polypropylene (Prolene, ard) plug; however, patient did not have relevant history of hernia repair and this was correctly diagnosed as lymph node (arrow). 704 JR:195, September 2010

5 Imaging of Prolene Plug Hernia Repair Fig year-old man with lung cancer who underwent staging PET/CT examination. PET/CT image shows soft-tissue mass (arrow) anterior to right iliac vessels without 18 F-FDG uptake. Clinical history revealed that this mass was polypropylene (Prolene, ard) plug. Fig year-old man who underwent MR enterography for evaluation of suspected flare of known Crohn s disease. and, Polypropylene (Prolene, ard) plugs (arrows) are seen to have low signal on 3D T1-weighted fat-saturated volumetric interpolated breath-hold examination image () and slightly high signal on T2- weighted fat-saturated image (). C and D, Periphery of Prolene plug may enhance (white arrows, C). Presence of herniorrhaphy scar and susceptibility artifact (black arrows, C) and surgical clips (arrows, D) indicate surgery as cause. Fig year-old man who underwent staging PET/CT for lung cancer. PET/ CT image shows intense uptake in left inguinal soft-tissue mass (arrow). Without correct clinical history of polypropylene (Prolene, ard) plug, this mass may have been misdiagnosed as metastatic disease and patient erroneously upstaged. C D JR:195, September

6 Cronin et al. Fig year-old woman who underwent pelvic MRI for evaluation of uterine lesion. She had recent right inguinal hernia repair. C, MR images show T1-weighted low signal (), T2-weighted intermediate to low (), and signal enhancing (C) polypropylene (Prolene, ard) plug in right inguinal region (white arrow). Postoperative peripherally enhancing seroma is also visualized (black arrow). Fig year-old man who underwent prior polypropylene (Prolene, ard) plug hernia repair. t follow-up imaging, Prolene plug had migrated into and distally within right inguinal canal (arrow). C 706 JR:195, September 2010