Pātiki and Waharua Kōpito patterns
- Occurs in 5 percent of ectopic pregnancies
- Irregular fluid collection, centrally within endometrial cavity
- Irregular shape
- No double decidual reaction
- No yolk sac
- May be difficult to differentiate from early intrauterine pregnancy or decidual cyst
- A decidual cyst and early gestational sac are usually eccentric
- A pseudosac is central and often contains blood clot or mobile debris.
Free fluid or haemoperitoneum
- Describe free fluid as simple or complex.
- Quantify the amount, that is, small, moderate, large, deepest pocket, confined to pelvis, present in upper abdomen, etc. Document fluid at or above the uterine fundus.
- If small amount of simple fluid, ectopic is likely not ruptured.
- A small amount of complex fluid does not always indicate rupture. This can be due to leak from the end of the tube, but early rupture is not excluded.
- A moderate to large amount of complex fluid / haemoperitoneum is suggestive of rupture.