Is it important how the Chazon Ish knew urology?

From Cross-Currents, a guest post from Rabbi Dovid Landesman, which begins:

I have an acquaintance in Los Angeles, a urologist who is also a well-respected talmid chacham. To establish his credentials let me say that he has completed three cycles as the maggid shiur in a local daf yomi. He told me recently that he received a call from a young man in Bnei Brak who was writing a sefer on hilchos k’rus shafchah and wanted to come to Los Angeles to consult on the medical aspects of the condition. The doctor agreed and when the mechaber arrived, they spent a week reviewing the material. One of the sources which they went through together was the Chazon Ish on Yoreh Deah.

My medical friend told me that he was absolutely astounded by the Chazon Ish’s mastery of anatomy as evidenced in his sefer and speculated what was the source of the Chazon Ish’s knowledge. Clearly he did not have a copy of Gray‘s Anatomy under his pillow. I raised the question to another friend, one of the local rabbonim, who showed me a teshuvah from Rav Wozner shlitah maintaining that the Chazon Ish had ruach kodesh. One of my more skeptical friends conjectures that since the Chazon Ish grew up in close proximity to the medical library of the university in Vilna, it is not unlikely that he may have spent some time in the reading rooms learning anatomy. Whatever the case, and it doesn‘t really matter which is the truth, many people will agree that the Chazon Ish was one of the outstanding minds of the past century.

Emphasis mine. Perhaps it doesn't really matter because that was not the point of the post, but rather whether the world would be better off had the Chazon Ish become a doctor and cured cancer.

But of course it does matter, and matters greatly, how the Chazon Ish knew this. If one maintains like one of the local rabbonim, then one can deduce that personal righteousness of an individual is sufficient to grant him knowledge from On High about scientific matters. סוד ה' ליראיו. If so, we might readily extrapolate that the present Gedolim, who are surely extremely righteous, have deep scientific knowledge of the workings of the world, despite their coming

from a culture which looks often down on secular knowledge. And if the Chazon Ish did not value studying secular subjects where they had relevance to halacha, but got the right answer anyway, then perhaps a posek need not make himself familiar with the metzius either. Nor is it likely to be deemed important for the hamon am to have some familiarity with modern science and medicine. And if you think a Gadol is simply wrong for maintaining a geocentric model of the universe, or a flat earth, or that gentiles have fewer teeth than Jews, or (and here to issues of greater concern) that the earth is young, or than evolution is nonsense and heresy, then you are not only a kofer but an ignorant one at that, for surely your shallow observations and the shallow observations of modern scientists are nothing compared with the truth which these tzadikim intuited with their ruach hakodesh.

And further, if this was true of the Chazon Ish, who was a recent Acharon, then al achas kama vechama it is true of Chazal. They must have had ruach hakodesh. And so one is a heretic for claiming that Chazal could err in science. If anything in the gemara appears to be scientifically inaccurate, the gemara either must be interpreted non-literally, with a convenient deep mystical significance, or else their science is true and it is the kofer scientists who are in the wrong.
On the other hand, if one maintains that the Chazon Ish was willing to make use of regular channels to achieve his knowledge of science and medicine; and that this was important information to get in order to render pesak, then we might derive another equally important set of conclusions. One is that there is not this automatic deep knowledge of all things medical and scientific on the basis on tzidkus. Therefore, a posek who eschews such knowledge, and paskens on such matters anyway, is giving a deficient pesak. One must know both Torah and the metzius. Furthermore, it is more likely for one to deem it important for the hamon am to be familiar with science. And if dentists all say that both Jews and gentiles have 32 teeth, yet a rabbinic source, or a modern Gadol says otherwise, then one is not a kofer for respectfully disagreeing with that Gadol, and perhaps even seeking psak in relevant matters from those rabbonim who are familiar with the science.

And furthermore, it is yet another example of rabbis in each time and place relying on the scientific knowledge of their time to make psak. If he read contemporary medical journals, then this is wonderful. But who says that all the information in those medical journals represented the precise reality? (On the other hand, in a matter of anatomy and which part goes where and functions how is going to be more or less accurate.) But science is often making great strides in development and adding new insights. And so we are saying that the Chazon Ish based himself on contemporary medical knowledge. Just as did Ibn Ezra; just as did Rambam. And then what about Chazal. Sure, we don't render them superhuman if they relied on contemporary medicine. But the approach is a normal, intelligent, and correct one for them to take. You need to apply Torah to reality, and you determine the reality as best you can for your time and place.

Rabbi Slifkin, in a comment on the post, reports:

I once asked Rav Gedaliah Nadel z”l, one of the foremost talmidim of the Chazon Ish, about the Chazon Ish’s medical knowledge. He told me that the Chazon Ish’s knowledge came from reading medical journals.

There you have it.

Meanwhile, the Chazon Ish's deep knowledge is used all the time to argue against science and the importance of science. In The Siddur Speaks to Us, published by Feldheim, it is used for precisely this purpose, in the context of emunas chachamim, to explain how Gedolim can pasken on matters studied in university when they haven't studied there. (Start from the second-to-last paragraph on the preceding page.)

There (and it is in the book) is this famous story of the Chazon Ish who suggested how to perform brain surgery, where he later said that he got the insight from hilchot traifah as described in Chullin. Thus, everything is contained in Torah.

But if he regularly studied medical journals, then this is where he got his knowledge from. If the story is indeed to be believed, and the additional detail that he got his insight from the gemara in chullin, I would say that it was a combined knowledge. Some detail in a gemara can spark an insight into the general science one knows, or a strong knowledge of science can help one understand what exactly the gemara is talking about.