He set aside this document and searched for a few related articles. One review stated that hypertrophic pachymeningitis presents with a variety of symptoms, including headache, blurred vision, diplopia, hearing loss, cranial nerve palsy, cerebellar ataxia, and limb weakness. Due to its atypical symptoms, it is often misdiagnosed. The key to diagnosis is performing an enhanced cranial MRI scan.

Zhaxi printed these articles and gathered materials about the etiology, pathology, diagnostic criteria, and treatment plans for hypertrophic pachymeningitis. He organized all the information into a folder and then drew a mind map in his notebook, placing the patient’s symptoms at the center and listing all possible diagnoses. He used the exclusion method to rule them out one by one. In the end, only a few possibilities remained—hypertrophic pachymeningitis, intracranial venous sinus thrombosis, low cranial pressure syndrome, autoimmune meningitis. Intracranial venous sinus thrombosis can be ruled out by performing magnetic resonance venography. Low cranial pressure syndrome can be excluded because the patient’s intracranial pressure is elevated rather than reduced. Autoimmune meningitis, normally presents with increased cell count or protein in cerebrospinal fluid, but the patient’s cerebrospinal fluid was normal, making it less likely. Therefore, the most probable diagnosis is hypertrophic pachymeningitis.

He closed his notebook, checked the clock, and realized it was already noon. He stood up, grabbed the documents, and headed to Yang Ping’s office.

Yang Ping was eating in his office. Seeing Zhaxi enter, he put down his chopsticks: "Any findings?"

Zhaxi placed the documents on the desk and began his report. He discussed all the information he gathered, his analysis process, and the reasons for excluding other diagnoses, explaining them one by one. Finally, he stated his conclusion: "Professor Yang, I suspect this patient has hypertrophic pachymeningitis and recommend performing an enhanced cranial MRI scan for confirmation."

Yang Ping listened quietly before speaking. He flipped through the documents, studying them page by page. After about ten minutes, he looked up at Zhaxi: "I generally agree with your reasoning process, but there’s one issue: the articles you found are all from foreign case reports. Hypertrophic pachymeningitis is very rare domestically. Have you considered other, more common diagnoses?"

Zhaxi thought for a moment and replied: "Yes, intracranial venous sinus thrombosis can be ruled out with MRV. Autoimmune meningitis is unlikely since the patient’s cerebrospinal fluid is normal. Low cranial pressure syndrome is excluded due to elevated intracranial pressure. Tuberculous meningitis, the patient’s cerebrospinal fluid normal, no symptoms of tuberculosis poisoning, can be ruled out. Tumorous meningitis can also be excluded, as the patient’s cerebrospinal fluid normal, no medical history of primary tumor."

He paused, then said: "There’s also the possibility of neurofibromatosis. But neurofibromatosis often presents with other systemic symptoms like lung issues, skin, and joints. The patient doesn’t have these symptoms. Moreover, neurofibromatosis in cerebrospinal fluid usually presents with increased cells or proteins, but the patient’s cerebrospinal fluid is normal, making it unlikely."

Yang Ping nodded and said: "Your analysis is comprehensive, but there’s one diagnosis you haven’t considered."

Zhaxi was startled: "What?"

Yang Ping replied: "Paraneoplastic syndrome."

Zhaxi opened his mouth but couldn’t speak. Paraneoplastic syndrome, immune-mediated neurological damage caused by tumors, can appear before the tumor is discovered. It has a variety of manifestations, including cerebellar degeneration, limbic encephalitis, and peripheral neuropathy. The patient’s subacute cerebellar ataxia indeed matches the manifestations of paraneoplastic cerebellar degeneration, but paraneoplastic syndrome typically doesn’t elevate intracranial pressure. Zhaxi expressed his thoughts.

Yang Ping nodded: "You’re right, paraneoplastic syndrome typically doesn’t cause increased intracranial pressure. But this patient has elevated intracranial pressure, making paraneoplastic syndrome unlikely. However, in your analysis, you should mention this differential diagnosis and explain why it’s ruled out. This is complete clinical reasoning, considering all possibilities, which requires strong knowledge base, from textbooks, literature, teachers’ instructions, clinical experience..." 𝗳𝚛𝗲𝕖𝚠𝚎𝚋𝗻𝗼𝕧𝗲𝐥.𝚌𝚘𝐦

Zhaxi lowered his head and added a line in his notebook: Differential diagnosis: Paraneoplastic syndrome ruled out due to increased intracranial pressure.

Yang Ping stood up and picked up the phone on the desk: "Neurology Department? It’s Yang Ping, the patient in ward seven. I suggest performing an enhanced cranial MRI along with MRV to rule out venous sinus thrombosis. Okay, thank you."

After hanging up the phone, he turned to Zhaxi: "Do the MRI tomorrow morning. Once the results are out, you analyze them."

Zhaxi nodded, feeling both nervous and excited.

The next morning, Zhaxi arrived early at the MRI room. The patient, guided by the technician, entered the scanning area, while Zhaxi stood at the glass window of the control room, watching the images gradually appear on the screen. The technician first did a plain scan, T1-weighted, T2-weighted, FLAIR, layer by layer. Zhaxi stared at the screen, his heartbeat quickening, next to him was Dr. Fang Chuan from the imaging department.

In the plain scan images, no significant abnormalities were seen in the brain parenchyma. No tumor, infarction, or bleeding. Then the technician began the enhanced scan, injecting the contrast agent, waiting for a few minutes, then starting the scan. The enhanced images displayed layer by layer.

Currently, Professor Yang is training him on reading various images, including MRIs, but he doesn’t have that level of skill yet. He needs to rely on Dr. Fang for the results.