Portal de Periódicos da CAPES

Lithopedion

1952; Radiological Society of North America; Volume: 58; Issue: 2 Linguagem: Inglês

10.1148/58.2.235

1527-1315

Samuel D. Hemley, Aaron Schwinger,

Ectopic Pregnancy Diagnosis and Management

The word Lithopedion is a descriptive term derived from the Greek lithos, meaning stone, and paidion, meaning child, to designate a fetus that has become stony or petrified. There are no classic clinical signs or symptoms which are of aid in the diagnosis. The majority of cases have been discovered at unrelated surgical procedures, during routine roentgenography of the abdomen, or at necropsy. Küchenmeister's classic article (5), in 1881, remains the basis of our present classification. He noted that calcification may involve either the fetus, membranes, or placenta, or any combination of these structures. On this basis, he proposed the following classification : 1. Lithokelyphos (stone sheath or egg shell), in which the membranes alone are calcified and form a hard shell surrounding the fetus. The fetus may undergo slight change only, or may be completely skeletonized, but is not involved in the process of calcification. 2. Lithokelyphopedion (stone sheath child), in which both the membranes and the fetus are calcified. 3. True lithopedion (stone child), in which the fetus is infiltrated with calcium salts and calcification of the membranes is negligible. Oden and Lee (10), in 1940, enumerated the following conditions necessary for the development of a lithopedion: (1) The pregnancy must be extra-uterine. (2) The fetus must survive in the abdomen for more than three months (otherwise it is absorbed). (3) The condition must escape medical notice. (4) The fetus must remain sterile. (5) The necessary conditions for the deposition of calcium must be present, i.e. minimal and sluggish circulation. In reviewing the literature, one is impressed with the paucity of reports in the English language (impression of cases reported prior to 1925). Schrenk, quoted by Schumann (13), in 1893 gave the incidence of lithopedion formation in ectopic pregnancy as 1.8 per cent, or 11 among 610 cases. Bainbridge (1) in 1912 estimated the incidence as 1.5 per cent, or 9 among 626 cases. In 1928 Masson and Simon (7) at the Mayo Clinic reported 9 cases in 445 extra-uterine pregnancies, or 2 per cent. In 1939, Mathieu (8), adding 31 cases to those previously collected, reported a total of 229 cases in the literature. Of the 31 cases, 8 were discovered by roentgenography. Reeves and Lipman (11), in 1941, brought the grand total of previously reported cases to approximately 236, covering five centuries. At the time of their publication, 247 cases had been reported. Mathieu's summary shows the patients to range in age from thirty to one hundred years, with a period of retention from four to sixty years. Mathieu also collected 274 recorded instances (up to 1936) of combined intra-and extra-uterine pregnancies, but was able to find among these only one case in which lithopedion developed. He added another example. Umnowa (16), in 1934, reported a case in which calcified masses were removed from either side of the abdomen.