The Engineer's Eye
The cafeteria’s lunch service was nearing its end for the late midday meal. The rice grains felt as rough as sand, scattering awkwardly in his mouth. The lukewarm doenjang soup on the tray sloshed precariously as it cooled. Ijun loosened his grip slightly on the chopsticks and lowered his gaze. The preview charts for the two surgical cases scheduled that afternoon were precariously spread out next to the stir-fried pork.
“Come on, man. Just eat when you’re eating. You’re going to get indigestion, hyung.”
Lim Dohyeon from neurosurgery’s first year yanked out the chair across from him and sat down, scolding him lightly.
“At this rate you’re headed straight for the ER with stomach cramps.”
Ijun answered indifferently without lifting his eyes from the chart.
“I don’t have enough time to review the afternoon cases.”
“Making time to eat is a skill too!”
“Yeah, yeah… But why are you here without a tray? Aren’t you eating?”
Dohyeon glanced around quickly, then leaned his upper body close across the table.
“I got a real headache of a case dropped on me.”
Ijun quietly set down the pen he had been holding. The lowered tone of Dohyeon’s voice had completely stripped away its usual playfulness. This wasn’t simple grumbling; it was a clear request for help.
“Unofficial consultation, then.”
“Obviously.”
Dohyeon pulled his smartphone from his coat pocket and unlocked it. The screen displayed a captured brain MRI image. After a quick scan of their surroundings, he launched into a rapid-fire briefing.
“Thirty-eight-year-old male. Acute headache starting two days ago, accompanied by mild weakness in the right upper extremity. MRI picked up a lesion in the left parietal lobe. Size is roughly two centimeters.”
Ijun took the phone and used two fingers to zoom in on the image with meticulous care. The old habit from his biomedical engineering master’s days—analyzing tens of thousands of brain scans pixel by pixel—quietly resurfaced.
“What’s the problem?”
“The lesion borders are too ambiguous. I can’t get a clean read.”
Ijun’s eyes rapidly scanned the image’s contrast levels. Dohyeon rubbed his face in frustration.
“Our professor is leaning toward metastatic tumor based on age and speed of symptom onset.”
“But you don’t think so.”
“No matter how I look at it, it doesn’t match a metastatic pattern. It’s driving me crazy.”
“Did you screen every possible primary site?”
“Chest and abdominal CTs, all of them.”
Dohyeon let out a long sigh.
“There wasn’t a single finding that suggested primary cancer.”
“What about the contrast enhancement pattern on the MRI?”
“Swipe to the next image.”
Ijun swiped the screen, revealing the T1-weighted image after contrast administration.
“The central enhancement is weak.”
“Right.”
“But the periphery is taking it up relatively strongly.”
Dohyeon lightly smacked the table.
“See? It’s not just me, right?”
“If it were a metastatic malignant tumor, the entire nodule should show uniform, strong enhancement,” Ijun said, pointing at a specific area with the tip of his pen. “Or there should be a very distinct ring pattern from central necrosis. This is neither.”
“This pattern doesn’t match the metastatic tumor profile at all.”
Ijun swiped back to the previous image.
“How does the surrounding edema look?”
Dohyeon indicated another angle on the screen.
“The edema is far less than you’d expect for the lesion size.”
Ijun nodded, his voice filled with certainty.
“A tumor that has metastasized to the brain should come with extensive vasogenic edema compressing the surrounding brain tissue. The proportions here are completely off.”
“If it’s not metastatic, then what is it?”
Dohyeon looked at him with desperate eyes.
“We can’t completely rule out an early primary brain tumor,” Ijun said, sliding the phone back toward Dohyeon. “But the overall picture—contrast pattern and edema extent—points much more strongly to an inflammatory lesion or demyelinating disease.”
Dohyeon’s eyes widened in shock.
“Hyung.”
“What?”
“You are a general surgery resident, right?”
Ijun downed the rest of his water in one gulp.
“No, seriously—since when? How are you reading MRI contrast patterns more precisely than me, a neurosurgery resident?”
“It was my main focus when I was studying biomedical engineering before medical school.”
“What?”
“Signal intensity distribution in brain imaging and contrast uptake pattern analysis. That was the topic of my thesis.”
Dohyeon let out a dazed, hollow laugh.
“The final diagnosis should of course come from your professor,” Ijun added as he neatly stacked the chart copies. “I only pointed out the physical contradictions in the imaging pattern.”
Dohyeon’s gaze dropped back to the phone screen.
“You’re right, hyung.”
“……”
“From the first time I saw the film, something about a demyelinating disease kept bothering me. But when the professor called it metastatic, I thought I must have misread it.”
Ijun looked straight at him with a serious expression.
“If you spotted that kind of error, you should have reported it to the professor immediately and corrected the direction.”
“Would that come out of your mouth so easily?”
“……”
“How is a first-year supposed to talk back to a professor who might as well be the sky above us? Not everyone is like you, hyung.”
“Hmm… I know it’s not my place to say this, but instead of directly contradicting the diagnosis, try changing your delivery strategy. Present other possibilities as assumptions first…”
Ijun slipped the pen back into his coat pocket.
“Or suggest additional tests for differential diagnosis through an indirect route.”
Dohyeon looked stunned.
“Do you always have those kinds of detour routes ready when dealing with superiors?”
“It’s not easy,” Ijun said, slowly rising from his seat. “But if you swallow that uneasy feeling and stay silent, the damage goes straight to the patient. Doesn’t it?”
Dohyeon couldn’t find a rebuttal and hung his head. After a moment of silence, he lifted it again with renewed determination.
“Then what test should I suggest right now to pull a differential diagnosis?”
“Cerebrospinal fluid examination.”
“Lumbar puncture, you mean?”
“It’s the most direct and the results come quickly.”
Ijun picked up his empty tray.
“If inflammatory markers or demyelinating antibodies show up in the CSF, that ends the discussion. Even if it is malignant, cytology can clearly differentiate it.”
Relief finally spread across Dohyeon’s face.
“Thank you. Seriously. Now I know exactly how to push this.”
“Remember, this is strictly an unofficial consultation.”
Ijun drew the line as he headed toward the dish return station.
“Of course. I swear I won’t mention your name.”
Dohyeon stood up and pointed at the tray.
“Hurry up and finish eating. You said you didn’t have time for the afternoon cases.”
Ijun looked down at the completely cold rice bowl. The sense of fulfillment from having caught one system error more than made up for the lost warmth of the meal.
Three days later, Ijun was returning to the fourth-floor ward station after finishing afternoon rounds. In the middle of the hallway where nurses carrying charts hurried past, a familiar voice called out.
“Hyung!”
Dohyeon jogged over and fell into step right beside him.
“The CSF test results are back.”
Ijun kept walking at the same pace, eyes forward.
“What did they show?”
“Early-stage multiple sclerosis.”
“So it was a demyelinating disease.”
Dohyeon continued in an excited voice.
“The possibility of metastatic malignancy was cleanly ruled out.”
A faint curve formed at the corner of Ijun’s mouth.
“That’s good to hear. How did the professor react?”
“When I first brought up the additional test, his expression was honestly terrifying.”
Dohyeon made a show of wiping his chest in relief.
“But once the results came out and the diagnosis flipped, his attitude changed completely. He praised me for accurately identifying a difficult case to differentiate. Said I did really well. I feel like I aged ten years and then got them back.”
“How did you frame the report?”
“I used exactly the template you gave me. I laid out the CSF results as an assumption and pulled the full differential list for demyelinating diseases. When I delivered it politely in report form, it finally landed.”
“You handled it well.”
“It was all because you spoon-fed me the answer. Thanks.”
Ijun stopped walking abruptly and turned to look at him.
“That’s right. I’m the one who found the physical contradiction in the imaging pattern.”
“…Huh?”
“But convincing the professor in the clinical setting was entirely your ability. In the end, changing the patient’s treatment direction was your achievement.”
Ijun drove the point home firmly.
“The credit belongs to you.”
Dohyeon let out a short, disbelieving laugh.
“You’re always like this. Passing all the credit to others and slipping away like a shadow.”
“It’s just a clear division of roles.”
Ijun started walking toward the station again.
“Next time you hit another wall you can’t get past, bring it to me quietly through the unofficial route.”
Dohyeon burst into a bright laugh and turned toward the neurosurgery ward.
At that moment, Jeong Ujin, the anesthesiology fellow, came walking from the opposite corner carrying anesthesia records. His usual dry appearance—blue surgical scrubs under a white coat—looked as impassive as ever. Ijun gave a light nod and was about to pass by when—
“Doctor Baek.”
Jeong Ujin called out without stopping, eyes still fixed forward. Ijun matched his stride so they walked side by side.
“Yes?”
“You were having a rather serious conversation with that neurosurgery resident earlier.”
Ijun answered calmly.
“He’s a close classmate.”
“It didn’t seem like simple classmate chatter.”
Jeong Ujin’s gaze remained fixed on some invisible point in the air.
“The atmosphere felt like case discussion.”
Ijun inwardly let out a small sigh of admiration. He had thought the man only read vital signs on monitors in the operating room. Yet his intuition for picking up the weight of a conversation from nothing more than hallway tension was impressive.
“It definitely wasn’t a surgical case.”
“I wasn’t eavesdropping, but the tension between you two was obvious.”
Ijun responded in a measured tone.
“It was an extremely private exchange of opinions between classmates.”
“So.”
For the first time, Jeong Ujin turned his head and glanced at him.
“Did that neurosurgery resident’s patient case get properly directed?”
“Yes. It resolved well, fortunately.”
“Then that’s all that matters.”
Jeong Ujin tossed the short, indifferent remark into the hallway and disappeared through the automatic doors without a backward glance.
Ijun stood still for a moment, quietly staring at the closed doors. Every situation had been neatly wrapped up within the range of control.
Then his on-call phone in his coat pocket began to ring with a sharp, insistent vibration. It was a call that tore through the ward’s peaceful atmosphere in an instant. Ijun reflexively pulled out the phone and checked the caller ID. It was the emergency room.
EMERGENCY ROOM
“Yes, this is Baek Ijun, first-year general surgery resident.”
An urgent intern’s voice poured out from the receiver. The unofficial consultation was over. Now a battlefield he had to take full responsibility for was waiting.
With a hardened expression, Ijun turned on his heel and began running toward the emergency room.