D. Ruter1, W. Chen4, R. Garza5, D. Eiferman3, R. Skoracki2 1The Ohio State University College Of Medicine,Columbus, OH, USA 2The Ohio State University College Of Medicine,Department Of Plastic Surgery,Columbus, OH, USA 3The Ohio State University College Of Medicine,Department Of General Surgery,Columbus, OH, USA 4The Ohio State University College Of Medicine,Department Of Pathology,Columbus, OH, USA 5PRMA Plastic Surgery,San Antonio, TX, USA
Introduction: Lymphedema is an accumulation of lymph fluid in the interstitial space that is most commonly due to surgical resection of lymph nodes secondary to malignancy. Standard of care compression and mechanical drainage based treatments are time intensive and provide limited long term relief. Autologous lymph node transfer (ALNT) is a microsurgical treatment in which a vascularized lymph node flap is harvested with its blood supply and transferred to the affected extremity to improve clearance of lymph fluid. A number of donor sites, including the groin, axilla, submental, and supraclavicular regions have been described as potential donor sites for vascularized lymph node containing free flaps. An ideal donor site minimizes the risk of iatrogenic lymphedema while being easily accessible with few potential complications. Previously, our group has utilized intraabdominal jejunal mesentery lymph nodes and omentum flaps for ALNT. We hypothesized that the mesoappendix could be harvested minimally invasively as an expendable "spare part" and would be ideal for transplantation if vessel size is adequate and a reliable number of vascularized lymph nodes can be included.
Methods: In this IRB approved study, 25 mesoappendix specimens (22 appendectomy and 3 right hemicolectomy) resected for benign disease underwent gross pathologic examination for determination of the presence of lymph nodes and measurement of the appendicular artery and vein caliber and length.
Results: A single lymph node was present in two of twenty-five (8%) specimens. Mean artery and vein calibers at the point of ligation were 0.87 and 0.86 mm, with mean lengths, as measured from the appendix mesentery to the ligated vessel end, of 1.70 and 1.84 cm, respectively. The two measurable right hemicolectomy specimens had an artery diameter of 1.2 mm, and vein diameters of 1.1 and 2.2 mm.
Conclusion: Mesoappendiceal lymph nodes were inconsistently present. The artery and vein calibers of 46% of the specimens were greater than 0.8 mm, the minimum caliber we prefer for microsurgical anastomosis. Maximal vessel caliber determination was limited by the site of vessel ligation chosen by the operating surgeon, and thus may be underestimated by our study. The exact role of the lymph node itself is not exactly delineated in the treatment of lymphedema, but evidence suggests that greater numbers of lymph nodes transplanted seem to have greater efficacy in removing lymph fluid. The mesoappendix, while it contains few or no lymph nodes is attached to the appendix, which contains a great number of lymphoid follicles in the submucosa. The uncertain role of this tissue in the treatment of lymphedema will require further investigation as a potential solution. However, for patients suffering from lymphedema, the mesoappendix can easily be explored and evaluated for the presence of lymph nodes and sufficiency of the vascular pedicle if planning to do an abdominal based lymph node transfer.