The Neurology Department was on the seventh floor of the Sanbo Hospital inpatient wing. Zhaxi walked down the corridor and found the Patient’s Ward. It was a three‑bed room, and the Patient was in the bed by the window. When he pushed the door open, the Patient was leaning against the head of the bed looking at her phone, her husband sitting beside her.

"Hello, I’m Professor Yang’s Student, Doctor Zhaxi, I’m here to take a look at you." Zhaxi tried to make his voice sound calm.

The Patient raised her head. She was a gentle‑looking woman wearing glasses, her complexion a bit pale. She smiled, but there was fatigue in her smile: "Hello, Doctor Zhaxi. You’ve been doing ward rounds for several days already, what exactly is this illness?"

Zhaxi did not answer, but instead asked, "May I ask you a few questions first?"

The Patient nodded. Zhaxi sat down, opened his notebook, and began to take the Medical History. He asked in great detail: When did the headache start? What was the nature of the pain? What location? Any precipitating factors? Any associated nausea or vomiting? How did the blurred vision come on—suddenly or gradually? Any double vision? When did the right‑sided limb weakness begin? Did it appear suddenly or worsen gradually? Any sensory abnormalities? Any bowel or bladder dysfunction? Before onset, any history of a cold, diarrhea, trauma, or vaccination? Any chronic Medical History? Any long‑term medication use? Any family history of hereditary disease?

Zhaxi marveled that he was actually this rigorous and detailed in taking a Medical History; in the past he was always forgetful and careless.

The Patient answered one by one. The headache had started three months earlier, with no obvious trigger—one morning she simply woke up with a headache and thought she’d just slept poorly. After that it was on and off: sometimes it wouldn’t hurt for several days, sometimes it would hurt for several days in a row. The blurred vision also came on gradually; at first she thought her glasses prescription was no longer sufficient, but getting new glasses didn’t help. The right‑sided limb weakness had appeared suddenly a week earlier: that morning when she got up to pick up a cup, the cup slipped from her hand, and only then did she realize her right hand had no strength. Her gait was also unsteady, like she was drunk. Before onset she had not had a cold, diarrhea, trauma, or vaccination. She had no hypertension, diabetes, or Heart disease. She was on no long‑term medications. Both parents were healthy, with no hereditary disease.

Zhaxi jotted down all the information, then stood up and said to the Patient, "I’ll do another physical examination for you, is that okay?"

The Patient nodded. Zhaxi examined her from head to toe: pupils equal and round, brisk light reflexes. Fundoscopy showed that the borders of both optic discs were indeed blurred, with mild Edema. The Muscle Strength of the right‑sided limbs was indeed grade four minus; the left hand gripped strongly, the right hand was weaker. The right Babinski sign was positive. Finger‑to‑nose testing—having the Patient touch her own nose with the right hand—her finger wavered and could not hit the target accurately. Heel‑to‑shin testing was the same: when she raised her right leg to find the left knee, it also wobbled.

After finishing the exam, he packed up his tools and said to the Patient, "Thank you for your cooperation, I’ll go back and study this further."

Walking out of the Ward, Zhaxi stood in the corridor and ran through in his mind what he had just asked and found. A forty‑three‑year‑old woman, subacute onset with progressive worsening, mainly presenting with increased intracranial pressure and right‑sided cerebellar signs. Increased intracranial pressure: headache, papilledema, elevated cerebrospinal fluid pressure. Right‑sided cerebellar signs: right‑sided limb ataxia, decreased right‑sided limb Muscle Strength, positive right Babinski sign. But the head CT was normal, routine labs normal, cerebrospinal fluid routine normal. What disease was this? Was there something growing in the Brain? But the CT was normal, no mass lesion was seen. Intracranial infection? But the cerebrospinal fluid was normal: no increase in Cell count, no elevated protein, no pathogen. Cerebrovascular disease? But the CT showed no hemorrhage or infarction. Demyelinating disease? Multiple sclerosis? But the Patient had no signs of optic neuritis, no sensory abnormalities, no spinal cord symptoms. Autoimmune disease? But the Patient had no joint pain, rash, oral ulcers, or other manifestations.

Zhaxi went back to Yang Ping’s office, sat down, and recounted everything he had found and thought. Yang Ping listened without commenting, only asking, "What do you plan to do?"

Zhaxi thought for a moment and said, "I need to do a literature search. This disease is too atypical; I need to see whether there are similar case reports."

Yang Ping nodded. "All right, tell me after you’ve finished searching."

Zhaxi returned to the Study room, turned on the computer, and began searching PubMed. He used several combinations of keywords—intracranial hypertension, cerebellar ataxia, normal CT, normal CSF. Not many papers came up; he went through them one by one, reading the titles and abstracts.

After searching for about an hour, he found a case report from the journal Neurology, titled "A Case of Idiopathic Hypertrophic Pachymeningitis Presenting Initially with Intracranial Hypertension and Cerebellar Ataxia." Zhaxi opened the full text and quickly skimmed it. The Patient described in the case report was very similar to the Patient he had seen in the Ward: a middle‑aged woman with subacute onset of headache, blurred vision, and increased intracranial pressure, later developing cerebellar ataxia. Head CT was normal, cerebrospinal fluid routine was normal. Only after a contrast‑enhanced Brain MRI was performed did they discover diffuse thickening and enhancement of the dura mater.

Quite excited, Zhaxi kept reading. The article stated that hypertrophic pachymeningitis is a rare disease of unknown etiology, possibly related to autoimmunity. Diffuse thickening of the dura compresses Brain tissue and Nerves, leading to increased intracranial pressure and various neurological symptoms. Diagnosis relies mainly on contrast‑enhanced Brain MRI: on T1‑weighted images, thickening of the dura can be seen, with marked enhancement after contrast.