The surgical laugh

Dr Mazda Turel gives a thumbs up after performing a surgery in the middle of the Coronavirus-induced lockdown

I got a little worried when he started laughing at his brother's funeral two weeks ago," said a concerned wife, as Rusi, her 55-year-old husband, sat in front of me shaking his crossed legs with his hands clasped on his belly. He wore a chequered shirt with grey pants that complemented his pepper hair, and a confused look for why everyone was so perturbed about a few laughs.

"The other day, our cat had diarrhoea and defiled our expensive Persian carpet, and all he did was sit on the couch and laugh." "Not only has it been ruined, it doesn't smell as good anymore either!" Rusi added with a huge grin followed by a cachinnating guffaw.

"See, isn't this ludicrous?" she pointed, almost instructing me to fire him for having switched from being a caring and loving man to a callous embarrassment. "He chuckles at old people being unable to cross the road. He laughed so much, he snorted when I mentioned to him that our son and his wife got COVID-19. He has started behaving like that man from the movie Joker."

"Not the Raj Kapoor one!"Rusi interjected as I burst out into a bit of a giggle myself. "Yes, the actor whose name no one can pronounce properly," his wife concluded with exasperation, as she pulled out an MRI scan of the brain that their family physician had ordered.

"So, he's laughing at all the wrong things," I said, summarising her woes as I plugged in the MRI into the luminance of the X-ray box,"and this is why."With the back of my pen, I went on to circle a 3.5-cm tumour arising from the trigeminal nerve and pressing onto the brainstem. "A tumour in this location in known in extremely rare cases to produce pathological laughter," I explained, as they looked at me befuddled. "We'll remove it and he'll be fine," my confidence coming from seeing a similar outcome in my training days of this common tumour with an arcane presentation.

A couple of days later, we tucked under his right temporal lobe, drilling into a little quadrant of bone obscuring our vision. Neurosurgeons take a look into the glistening opalescence of the brain everyday, but the view is a tad different on each day. The brain is a variant shade of beige-pink, the nerves a diverse spectrum from white to yellow, and the corridors to access these tumours keep changing, making it a wondrous journey into enthralling nooks and crannies. There is a new treasure to be excavated every day. "Can I cut this?" is the most common question I voice aloud to the amusement of the team watching the surgery on the big screen. Most often, you know what you're about to cut, but on occasion, you end up nipping something you can't identify in the hope it's a part of nature's abundance.

We peeled the tumour off the nerve it originated from, and when we removed it completely, the dent it had made on the brain stem gently ballooned back to take its original form. "You think he'll stop laughing after surgery?" I indulged my assistant as we closed, a time of the operation where we resort to prosaic yet philosophical questions of life. "I think he has a great sense of humour; your surgery is only going to ruin it for him!" came the reply.

The morning after surgery, when neurosurgical patients are fully awake and alert, we check if they are oriented to time, place, and person, and do a thorough neurological examination to check for motor or sensory impairment, seeing if things had become better or worse. In Rusi's case, we needed to say or do something strange to see if he laughed. "We'll leave that for his wife to assess, after she spends the whole day with him," I decreed as we wrote orders to transfer him out of the ICU and into the ward, which deemed everything was perfect.

Two days later, we got a call from the emergency department about a 67-year-old lady who began crying violently and inconsolably for two hours after a glass of water slipped from her hand and smashed to the floor. On checking further, we realised that she wasn't hurt nor did the glass have any emotional value for her. The psychiatrist who was called into opine was also confused. Our astute neurologist ordered an urgent MRI that showed a stroke in the left thalamus. She was administered a clot-busting drug and we could see her tears dry up as the last few drops of medication emptied into her veins.

Pathological laughter and crying are uncommon manifestations of common neurological conditions. They don't have a motivating stimulus nor are they triggered by an impulse that would not have otherwise led to this reaction. Scientists term this as "emotional incontinence" and it is often seen in patients with amyotrophic lateral sclerosis, a form of motor neuron disease. We have also seen this in patients with multiple sclerosis, Parkinson's, and in some brain tumours.

We went to check on Rusi on the day of his discharge. I could hear a roar as I knocked on the door. "We haven't cured him, have we?" I turned to my colleague. "Hi Doc," he smiled as the door opened. "Is he still laughing at stuff he's not supposed to?" I turned to his wife. "Nothing crazy so far," she said, her hands folded in gratitude. "Then what was he laughing at when we walked in?" I asked, my curiosity piqued. "Someone sent him a neurosurgeon joke!" "Let's hear it," I said, preparing myself to be embarrassed.

"How many neurosurgeons does it take to change a light bulb?" he asked, and then followed up with the answer after a sly grin from me. "Just one: he holds the bulb and the world revolves around him." I smiled, shaking my head at the comical impression people have of us, but appreciating the humour nonetheless.

The next time you see someone laughing nonsensically, don't hesitate to get a scan on him. If the scan is normal, you can safely diagnose him to be Parsi.

The writer is practicing neurosurgeon at Wockhardt Hospitals and Honorary Assistant Professor of Neurosurgery at Grant Medical College and Sir JJ Group of Hospitals.