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June 15, 2009

Image of the Month—Diagnosis

Arch Surg. 2009;144(6):589-590. doi:10.1001/archsurg.2009.69-b

Answer: Seroma

The histological examination revealed that the cystic mass contained reactive connective tissue. Thus, it was a well-organized seroma.

Seroma is a collection of serous fluid in the surgical wound. The size of the collection relates to the amount of dissection done between tissue planes and the amount of empty space in the surgical wound.1The exact pathogenesis of seroma remains a matter of debate. It has been postulated to be due to a local inflammatory response to the mechanical injury incurred by tissue dissection, as well as to the introduction of foreign material into the body.2The main risk factors are advanced age, big hernia sac, scrotal hernia, and transection of the sac with the distal part left behind.1,3

Because it mimics a postoperative recurrence of hernia, seroma has been a concern to hernia patients.4Seroma formation after laparoscopic inguinal hernia repair is reported with various rates (1.9%-22.9%) in the literature.4-6The mean size of seroma formations was reported to be 3.8 ± 1.7 cm.1Seroma is typically present after the third or fourth postoperative day, and its incidence peaks at the seventh postoperative day.1Patients with seroma formation usually worry that their hernia has recurred. Indeed, fluid usually fills the inguinal canal and previous hernia site, which creates a palpable mass. When examined, the wound appears raised, but it is not inflamed or tender. The mass is fluctuant and the fluid ballotable. Ultrasonographic imaging can confirm the diagnosis. Treatment consists primarily of observation. Aspiration is rarely needed, and the seroma is frequently reabsorbed by the body by the second or third month after surgery.1For that reason, seroma is not considered by many to be a complication after laparoscopic hernia repair. Moreover, as suggested by Park et al,7it should be considered a complication only if it persists for more than 6 weeks, increases steadily in size, or produces symptoms.

In a large study of 1903 laparoscopic hernia repairs, Schwab et al8concluded that seromas mostly occur in patients with large scrotal hernias, and most of the hernias disappear within 2 months. Only 0.9% of seromas persist and 0.2% of them require operative drainage. In another multicenter study of 1605 patients by Aeberhard et al,9the rate of postoperative seromas was reported to be 4.4% at the end of the third month and 2.1% at the end of the 12th month.

In evaluation of seromas by ultrasonographic imaging, more fluid is found to be collected at the end of the first postoperative day and first postoperative week, whereas after the end of the first month, the collections get smaller and the content gets denser, with capsule and septa formation in some cases.3Because the skin and subcutaneous tissue planes are undisturbed in laparoscopic repair, the serous fluid usually collects above the mesh in this area.

In the present case, the patient had 2 predisposing factors for the development of seroma: old age and a large scrotal hernia. He did not return to the outpatient department until 2 months after surgery, when he presented with a firm cystic mass in the right inguinal area. Upon palpation the mass seemed to be connected to the internal inguinal ring, but this hypothesis could not be proven with ultrasonographic imaging. At the time of surgery the cyst was connected to the inflammatory tissue, which had formed as a reaction to the mesh, around the internal inguinal ring. The cyst had multiple septa and contained a yellowish pulp. Histologic examination revealed reactive connective tissue, as expected. Although some studies mention that seromas that persist for more than 2 months transform into cystic formations, this is an extraordinary report of an organized seroma after a TAPP approach, the nature of which had been difficult to clarify before surgical intervention.

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Correspondence:Evangelos P. Misiakos, MD, Assistant Professor of Surgery, 76 Aigeou Pelagous St, Agia Paraskevi, Athens 15341, Greece (

Accepted for Publication:November 10, 2008.

Author Contributions:Study concept and design: Misiakos and Fotiadis. Acquisition of data: Preza. Analysis and interpretation of data: Misiakos, Liakakos, Macheras, and Fotiadis. Drafting of the manuscript: Misiakos and Preza. Critical revision of the manuscript: Misiakos, Liakakos, Macheras, and Fotiadis. Study supervision: Misiakos, Liakakos, and Macheras.

Financial Disclosure:None reported.

Lau  HLee  F Seroma following endoscopic extraperitoneal inguinal hernioplasty.  Surg Endosc 2003;17 (11) 1773- 1777PubMedGoogle ScholarCrossref
Bendavid  RKux  M Seromas. Bendavid  RAbrahamson  JArregui  MEFlament  JBPhilips  EH Abdominal Wall Hernias Principles and Management. New York, NY Springer Publishing2001;753- 756Google Scholar
Cihan  AOzdemir  HUçan  BH  et al.  Fade or fate: seroma in laparoscopic inguinal hernia repair.  Surg Endosc 2006;20 (2) 325- 328PubMedGoogle ScholarCrossref
Kapiris  SABrough  WARoyston  CMO’Boyle  CSedman  PC Laparoscopic transabdominal preperitoneal (TAPP) hernia repair: a 7-year two-center experience in 3017 patients.  Surg Endosc 2001;15 (9) 972- 975PubMedGoogle ScholarCrossref
Fitzgibbons  RJ  JrCamps  JCornet  DA  et al.  Laparoscopic inguinal herniorrhaphy: results of a multicenter trial.  Ann Surg 1995;221 (1) 3- 13PubMedGoogle ScholarCrossref
Leibl  BJSchmedt  CGKraft  KUlrich  MBittner  R Scrotal hernias: a contraindication for an endoscopic procedure? results of a single institution experience in transabdominal preperitoneal repair.  Surg Endosc 2000;14 (3) 289- 292PubMedGoogle ScholarCrossref
Park  ABirch  DWLovrics  P Laparoscopic and open incisional hernia repair: a comparison study.  Surgery 1998;124 (4) 816- 821PubMedGoogle ScholarCrossref
Schwab  JRBeaird  DARamshaw  BJ  et al.  After 10 years and 1903 inguinal hernias, what is the outcome for the laparoscopic repair?  Surg Endosc 2002;16 (8) 1201- 1206PubMedGoogle ScholarCrossref
Aeberhard  PKlaiber  CMeyenberg  AOsterwalder  ATschudi  J Prospective audit of laparoscopic totally extraperitoneal inguinal hernia repair: a multicenter study of the Swiss Association for Laparoscopic and Thoracoscopic Surgery (SALTC).  Surg Endosc 1999;13 (11) 1115- 1120PubMedGoogle ScholarCrossref