Leeper — On Retro-peritoneal Cavities. 



XIII. — Ox PiETEO-PEEiTONEAL Cavities. By George PtEGryALD Leepee, 

 student in Medicine, Trinity College, Dublin. (With Plate 5.) 



[Read 14th December, 1874.] 



The subject of retro -peritoneal pouches when taken in connexion 

 •with the occurrence in them of intra-abdominal herniae is a very in- 

 teresting one, especially as so few of these fossae exist. Only three 

 such cavities have as yet been described, which are as follow : — 



1°. The "Possa Duodeno-Jejunalis" on the left side of the 3rd 

 lumbar vertebra. — This fossa has been fully described by Huschke,^-' 

 and has been found the seat of an intra-peritoneal hernia by Treitz,f 

 Chiene,| Peacock, § and Gruber.H 



2°. The " Eecessus Ileo Coecalis" (fig 1). — This concavity is very 

 constant and is frequently a deeply-excavated hollow. It may be 

 from 0-25 of an inch to ' 1-25 inches in depth, and may be seen lying 

 between the mesenteriolum of the vermiform appendix, the plica, ileo- 

 coecalis, and the ccecum. This fossa has been described by Professor 

 Luschka of Tubingen^ ; it may (not unfrequently) contain a cyst.*^' 

 Hernia has been found herein by Engel.f f 



3°. The " Subcoecal Possa" figured in the sketch (fig. 2) has been 

 described by Luschka.jJ '^o example of hernia has as yet been de- 

 scribed as occurring in this fossa, as its mouth is always very wide in 

 proportion to its depth. It only exists when the mesocoecum is im- 

 perfect. 



Thi'ough the kindness of Dr. Macalister, who poiated it out to me, I 

 now bring forward another as yet undescribed form of these retro- 

 peritoneal fossae which came under my observation on the 16th of '^o- 

 vember last in the Trinity College Dissecting Eoom. 



On opening into the abdominal cavity of a man of about 55 years 

 of age, in the right iliac fossa, an abnormal fold of iliac fascia was dis- 

 covered bounding a sac or pouch of moderate size. It consisted of a 

 thin, strong semi-transparent arch extending outwards from the bor- 

 der of the psoas magnus muscle to the crest of the Ilium, part of the 



* Lelire von den Einge^^^eiden des Menschlischen Korpers. Leipzig, 1844, 

 p. 216. 



t Hernia retro-peritonealis. Ein Beitrag zur Geschichte innerer Hernier 

 Prag, 1857. 



% Journal of Anatomy and Physiology, 2nd Series, No. 2, 1868, p. 218. 

 ^ Trans: Pathological Society of London, Tol. 2., page 60. 

 II St. Petersburges Med. Zeitschrift, 1831, Bd. 1. 



1l Ueber die peritonseale umhiillung des Blinddarmes und iiber die fossa ileo- 

 coecalis. Yircho-w's Archiv, Vol. 21, 1861. s. 285. This sac is really a portion of the 

 visceral, and not of the parietal peritoneum. 

 ** Schott, "Wiener "VTochenblatt. No. 44, 1862. 

 tt "Wiener Med. "Wochenscbrifti 1861, No. 10. 

 XX Die Anatomie des Menschlischen Bauches, s. lo4. 



