The lowest point comes a few months later, when he undergoes an endoscopy-colonoscopy-biopsy. He has a bad reaction to the general anesthesia—as he comes out of it, his eyes bulge wide and he starts wailing, a loud, screechy sob that reminds me of ghok, the full-throated ceremonial wail of Korean funerals. My son’s voice brims with grief, the raw, shaking cry of a child who’s been abandoned, bereft and alone. It takes fifteen minutes to calm him down. The anesthesiologist says it’s fine, a “not ideal but not atypical” reaction he’ll forget about when the drugs are out of his system, but two months later, working on an “All About Me!” poster for preschool, he comes across a magazine picture of a doctor holding an anesthesia-­inhalation mask and glues it on the “things I don’t like” spot.

I first hear about hyperbaric oxygen therapy, or HBOT, about three months after the diagnosis, which is “celiac disease and ulcerative colitis, existing comorbidly,” according to the gastroenterologist’s report. (Note to doctors: Comorbidly is not a good word for children’s medical reports.) Long used by hospitals for carbon-monoxide poisoning and decompression sickness, HBOT is becoming a popular experimental treatment for a variety of conditions, from cerebral palsy and autism to Lyme disease. Damaged cells need oxygen to heal, so the theory is that deep penetration of extra oxygen can result in faster healing and regrowth. A patient gets that extra oxygen by sitting in a tank where the air pressure is increased, which allows the lungs to absorb more than they normally would.

A year prior, I would have dismissed HBOT out of hand. It’s not FDA-approved for ulcerative colitis, and I can’t find any double-blind studies proving its effectiveness. But with my child still in pain after months of standard treatments, his ribs showing through his skin, I’ve become desperate. The new standard becomes: Could this be harmful in any way? My son’s doctor doesn’t approve, exactly—he warns it might (and probably will) be a waste of time and money—but when I ask what he’d do if it were his own child, he sighs and admits he might try it.

We do 40 sessions over the next month, consisting mainly of double dives—one morning and one evening—which give me glimpses into the lives of the other patients. The majority are kids with cerebral palsy or autism, but the severity varies greatly; some are nonverbal or need feeding tubes, and others have anxiety or sensory issues that aren’t readily apparent. Despite this range, it’s remarkable how much intimacy builds. Partly it’s the atmosphere; once the hatch is sealed, we’re locked in a dark, confined space with an eerie confessional feel. There’s nothing to do except talk—no music, no magazines, no phones—so we trade our life stories, the minutiae of our day-to-day routines. But even more, it’s our kids, trapped in this chamber hour after hour, with no way out. There are dis­as­ters along the way, little and big. The near-daily bathroom emergencies teach us to keep pee jars and disinfectant wipes close by. One day, a girl with a fecal-smearing tic reaches into her pants, pulls out a handful of feces, and starts smearing it on the wall. When a thunderstorm knocks out power for several days, the generator keeps the HBOT functioning, but the AC and DVD are offline. It feels like a sauna inside, and the portable DVD player the operator has duct-taped outside a porthole is hard to hear. A ten-year-old boy with autism takes off his oxygen helmet in frustration and bangs his head against the steel wall. It takes all four adults to pull him away.

Toward the end of the 40 dives, I take my son for a hearing checkup. During the test, the audiologist frowns, a concerned look on her face. “What’s wrong?” I say, though I already know. It’s the HBOT. The pressurization harmed his ear, and now, in my quest to heal one part of his body, I’ve messed up another. My stomach lurches, and I’m trying to keep from throwing up when she says, “He has hearing in his right ear,” and hands me the chart. The line that has always been flat is showing response in lower decibels. Hearing. Only for bass tones. Probably not enough to hear voices, especially women’s voices. But still, it’s something. When I tell the other HBOT moms, they call it a miracle. I shake my head and say, “It’s not full hearing, just a little bit.” “Well, then,” one mom says, “it’s a little miracle.”

At the end of the summer, there are more little miracles. My son’s stomach has stopped hurting, and he’s gaining weight again. The girl with OCD has stopped fecal-smearing; her mother has tears in her eyes when she reports this, and we all whoop and high-five. The mom of a teenage girl with cerebral palsy says she’s been laughing out loud. “She’s making actual sounds. Can you laugh again, baby?” the mom asks, and the girl opens her mouth and says, “Huh.” It sounds somewhat mechanical, but the grin on her face makes it clear: It’s an exuberant, joyous laugh. We all join in, caught up in the wonder of this, the first deliberate sounds this girl has made in years.

Read the fill article in Vogue: