Exaviination of the Cervical Canal 105 



as shown in Fig. 43, and invading the peritoneal cavity. In 

 order to avoid wounding the uterus, the operator needs to 

 judge well the approximate length of the cervix and when 

 the end of the instrument reaches the region of the os uteri 

 internum, it should be directed slightly downward. That is, 

 using a curved instrument, as is always most convenient and 

 safest, the operator should at this time turn the instrument 

 so that the concave side of the curve is directed downward. 

 Ordinarily no metal instrument should pass far beyond the 

 OS uteri internum. In the ordinary empty, non-pregnant 

 uterus, the downward curvature of the uterus is so marked 

 that there is great peril of puncturing the walls if the instru- 

 ment is pushed more than one to two inches into the uterine 

 cavity. In addition to this danger, if the uterus is flaccid or 

 if the pushing of the instrument through the cervical canal 

 requires some degree of pressure, the uterus bends sharply 

 and the instrument catches in this and punctures the wall. 



If chronic cervicitis is present, it inevitably causes scle- 

 rosis of the annular mucous folds of the cervix, and the hy- 

 pertrophy of the sclerotic areas presses across against the 

 opposite side of the cervical canal, bending it but of its 

 course and narrowing its lumen. The sharp bendings of the 

 canal, with the intruding sclerotic and hypertrophied masses, 

 so impede the passage of the instrument that once it has 

 entered the uterine cavity, the resistance of the uterine wall 

 is not clearly recognizable if the instrument is pushed into 

 or through it. When using the dilators, therefore, the ad- 

 vancement of the instrument should cease when the uterine 

 cavity is reached. The length of the cervix, if doubt arises, 

 may be learned by rectal palpation. The same means may 

 be used to learn when the dilator has passed the cervical 

 canal. In all cases where the cervical canal is not freely 

 open and sufficiently direct to permit the easy passage of the 

 uterine catheter, it is prudent and advisable to use first the 

 uterine dilator. I have found the Palmer uterine dilator of 

 the human gynecologist, modified as shown in Fig. 39, the 

 best instrument for this purpose. It is small and the curva- 

 ture of its blades corresponds fairly well with the average 



