Similar to the extra colonic findings in virtual colonoscopy studies [8], the incidental diagnosis in VHSG can be classified according to its clinical importance: high, moderate and low.

The report of the unexpected lesions is of great responsibility for the radiologist because the next steps to follow depend on its valuation. On the other hand, the referral physician must know the reaches of the method requested and be ready to face the results comprehensively. It is imperative to consider at this point the importance of the extra time the radiologist puts into the exploration of the rest of the soft and bone pelvis. It is necessary to analyze the acquired axial images in their totality and give them a different treatment than the uterine evaluation.

As mentioned before, the frequency of these incidental lesions is low due to the fact that most of the patients are young, asymptomatic and are in a study for infertility. The unexpected findings of low clinical significance represent a large part of the reports, and generally do not require complementary exams to clarify their diagnosis. The lesions of moderate importance are usually doubtful or undetermined diagnoses, hence the anxiety produced by the uncertainty. In these cases a re-evaluation is vital, and its following depends on each particular case. One example is the unspecific bone lesions, that require new short term imaging studies. The potentially important findings are extremely rare in this group of patients. These are the ones that can affect the health of the patient. Despite their infrequency, one must always be watchful and ready for these findings due to their high impact on morbi-mortality.

Both functional as well as structural abnormalities affect the ovaries and can be the cause of infertility. For the fecundation to be a success, it is necessary that the ovulation process and follicular development be normal [9]. The study which evaluates these functional parameters, as well as the structural anatomic characteristics, is ultrasound [10]. The conventional hysterosalpingography studies can only infer the existence of an abnormality in the ovary size when displacement and compression is observed in the adjacent uterine tube [11]. Nevertheless, these findings are not specific, because the tubes have a variable position and because other processes can generate a mass effect of the ovaries. On the other hand, in VHSG exams, one can correctly individualize the ovaries, measure their size, and evaluate their density and position in order to characterize pathologic processes (Fig. 11.4). The instilled contrast material which passes to the peritoneal cavity helps delineate the ovaries outline. One disadvantage is associated to the lack of intravenous contrast which is fundamental to detect solid areas and pathologic signs.

The polycystic ovary syndrome is the structural abnormality that most frequently causes infertility [9]. The ovary is enlarged and multiple cysts of different sizes are distinguished in its interior (Fig. 11.5). There exist cases where a complicated cyst can be found, with a high density content that suggests hematologic remains, frequent in endometriosis cases (Fig. 11.6). Another finding difficult to diagnose are mature cystic ovarian teratomas. They are round or ovoid masses of different dimensions that characteristically present a heterogeneous density, predominantly fat, alternated with solid and calcium areas (Fig. 11.7). When the ovarian masses are not typically benign, a complementary evaluation is required for its improved characterization. The parameters that suggest a malignity are: an ovarian size larger than 4 cm, mixed internal structure (solid-cystic), parietal or septal thickening, and the presence of associated swollen lymph nodes or ascites [12, 13] (Fig. 11.8).