Advantages of intraoperative semiquantitative evaluation of myenteric nervous plexuses in patients with Hirschsprung disease

Counting myenteric ganglion cells in histologic sections: an empirical approach

“…We used the TZ in colonic resection specimens from patients with HD as a "testing ground" for our counting method because hypoganglionosis in the TZ has been observed consistently by others using a variety of approaches and incomplete resection of the TZ is a putative cause of persistent, postoperative obstructive symptoms [7,10,30,31,40]. When applied to 6 surgical specimens from patients with HD, our neuronal counts from 5 fullcircumference, Hu IHC sections were sensitive enough to detect the gradually distal to proximal neuronal density of the TZ.…”

“…The latter can be challenging histopathologic diagnoses, which should be based on rigorous and well-controlled quantitative data, but often rest on subjective impressions with uncertain reliability. One context in which ganglion cell density may be particularly important is the transitional zone (TZ) of HD, a hypoganglionic length of bowel that lies proximal to the segment of aganglionosis and varies from a few millimeters to several centimeters in length [7][8][9][10][11]. Some studies suggest that failure to resect the TZ along with the aganglionic segment may account for the postoperative obstructive symptoms observed in many HD patients [10,12,13], but conflicting data exist [14].…”

“…One context in which ganglion cell density may be particularly important is the transitional zone (TZ) of HD, a hypoganglionic length of bowel that lies proximal to the segment of aganglionosis and varies from a few millimeters to several centimeters in length [7][8][9][10][11]. Some studies suggest that failure to resect the TZ along with the aganglionic segment may account for the postoperative obstructive symptoms observed in many HD patients [10,12,13], but conflicting data exist [14]. Isolated hypoganglionosis (independent from HD) is also a putative cause of pseudoobstruction [15][16][17][18][19][20].…”

“…Potential variation in the circumferential distribution of neurons has important implications for choosing the biopsy size and site. In the TZ of HD, for example, the distribution of ganglion cells around the circumference is uneven, with irregularities in the "leading edge" of ganglion cells that extends into the aganglionic distal bowel [10,30,31]. Irregularity in the circumferential distribution of ganglion cells may be important in other contexts as well, and it is unclear whether biopsies that sample a portion of the circumference can be used to accurately estimate the full circumferential density of neurons in normal or diseased bowel.…”

Quantitative evaluation of myenteric ganglion cells in normal human left colon: implications for histopathological analysis

“…By contrast, the processing of wax-embedded material allows tissue specimens to be easily stored and handled without excessive care and to be made quickly available from archival collections. Some studies have been performed on paraffin sections to evaluate the organization of myenteric perikarya and networks (Aubé et al 2006;Hanani 2004) and to obtain semiquantitative counts of myenteric cells both in experimental (Sandgren et al 2002) and human (Smith 1993;da Silveira et al 2007;Boman et al 2007) colonic pathologies. In addition, routine hematoxylin-eosin staining, which has been shown to reveal myenteric ganglia and to identify patients with hypo-and hyperganglionosis (Smith 1993), can be used as a preliminary screening method, although it does not allow an accurate discrimination of small neurons from glial cells.…”