Quiz - Physiology - Equalizing

[Pedro Burrito]

From the Physiology section of the PADI Dive Theory Exam:

A(n) ___ may occur if a diver who is having difficulty equalizing blows too forcefully against a pinched nose.

a. round window rupture

b. reverse block

c. ear drum stretch

d. sinus squeeze

I will post a daily question from my exams to help newer divers and to encourage more experienced divers to interact gracefully and helpfully with the newer divers.

Reminder - this is a post in the Basic Forum and it is a green zone. Please be nice and on topic.

Thank you for your patience while we try to give people something to discuss other than Covid-19 and/or Politics. I will post the answer covered by the spoiler tag later today.

 

[Celt]

Didn’t know what A was so went for B

 

[scubadada]

This is excellent Ears & Diving - DAN Health & Diving

 

[tursiops]

The question describes a Valsava maneuver: pinch the nose and blow. It is the easiest to describe, but definitely not the only way to equalize and rarely the best. In my experience, many more divers are successful at equalizing (without endangering the ear!) using the Toynbee or Lowry maneuvers. See Middle-Ear Equalization | Ears & Diving - DAN Health & Diving and Beat the Squeeze: Equalize Like a Pro.

 

[TMHeimer]

It seems I got it right. Just an educated guess since I've never had any trouble equalizing (except with congestion, of course). I'm one of those lucky ones who do it internally with no other movement. I can pretty much go down an anchor line to 100' as fast as my hands will pull me.

 

[kelemvor]

I've never heard of "round window rupture". I assume "Round Window" = eardrum or something like that?

 

[Brett Hatch]

The eardrum is the membrane between the outer ear and the middle ear, also known as the tympanic membrane. The round window is a smaller membrane between the middle ear and the inner ear. There is also a second membrane between middle and inner ear, known as the oval window. Wikipedia actually has a pretty good article on this anatomy.

Most times when I have seen discussions along these lines, the concern is about the tympanic membrane, which happens to be right next to a needle-shaped bone. However, I could imagine round/oval membrane damage from too much air rushing in quickly, so voted for (a). The other options seems plausible as well, but not as serious, and not as directly related to a too-hard Valsalva.

 

[scubadada]

I've never heard of "round window rupture". I assume "Round Window" = eardrum or something like that?

No, the round window is shown in the nice diagram from the DAN article I posted in #3, a rupture of the round window may result in a perilymph fistula, if it does not seal and heal with conservative therapy, it may require surgery.

 

[Dizzi Lizzi]

total guess on my part based on the choices of rupture, block, stretch, and squeeze.
I chose A.

 

[Pedro Burrito]

Spoiler: Answer

a. round window rupture