An accurate description of PCH has been scant and perhaps nonspecific. Still, some research suggests that on history, patients may report a continuous, pulsatile, or pounding pain of variable intensity that appears within seven days of the surgery. Other common characteristics include symptoms on the same side as the surgical incision and improvement of symptoms over time.[6]

As with all headaches, it is imperative to rule out red flag signs including but not limited to paralysis, papilledema, drowsiness, confusion, memory impairment, loss of consciousness, focal neurologic signs, neck stiffness, sudden onset excruciating pain, or personality changes.

Some evidence points to scar neuromas as a potential trigger for headaches. Thus, it is essential to assess the scar site on the physical exam and evaluate the reproduction of headache pain with palpation.[9]

PCH is primarily diagnosed through history and physical examination. However, imaging may be warranted if intracranial pathology is suspected or red flags are found on examination. If so, a non-contrast head CT scan would be an appropriate first step.

According to the International Classification of Headache Disorders 3 Beta edition, the current criteria for diagnosis are as follows:

A. Any a headache fulfilling criteria C and D

B. Surgical craniotomy has been performed

C. A headache is reported to have developed within seven days after one of the following:

• The craniotomy
• Regaining of consciousness following the craniotomy
• Discontinuation of medication(s) that impair the ability to sense or report a headache following the craniotomy

D. Either of the following:

• A headache has resolved within three months after the craniotomy
• A headache has not yet resolved but three months have not yet passed since the craniotomy

E. Not properly accounted for by another ICHD-3 diagnosis.

Of note, persistent headache attributed to craniotomy differs from the acute headache criteria by the fact that it persists for more than three months after the craniotomy. About a quarter of patients who develop an acute headache attributed to craniotomy experience a persistent headache attributed to craniotomy. When a headache following craniotomy becomes persistent, the possibility of a medication-overuse headache should be considered.[10]

Unfortunately, research remains lacking in regards to current strategies to manage PCH. Therefore, options for consideration include using typical medications seen in the treatment of headaches with similar phenotypes. A list of these medications is beyond this review's scope, but, in the neurological population, care must be taken when using medications that may obscure the ability to monitor neurologic responses.[11]

This is of particular importance when opioids are prescribed. They remain a heavily relied upon option for moderate to severe pain, even with the risk of addiction, cognitive clouding, and respiratory depression. Worth noting is the ability to combine other analgesics with opioids to lessen the chance of adverse events. Some combinations in past studies include fentanyl and ketorolac or tramadol and diclofenac.[8]

Regarding prophylaxis, one single-center, randomized, the blinded trial found that a preoperative dose of 100 mg of diclofenac decreased the headache's intensity on postoperative day one and up to post-op day 5 for patients with infratentorial surgeries. Still, caution must be exercised due to the potential to increase the risk of bleeding using non-steroidal anti-inflammatory medications.[1]

Other interventions have been studied, either for PCH or post-craniotomy pain in general, but warrant more research before standardizing their use in these patients. These include transcutaneous electrical acupuncture stimulation, nerve blocks, gabapentinoids, COX inhibitors, and dexmedetomidine, a presynaptic alpha two adrenoceptor antagonist.

In the chronic phase, a shift to more non-pharmacological adjuncts may be considered. Alternatives to consider are physical therapy, acupuncture, TENS units, hot or cold packs, massage, or bio-behavioral interventions. A small case series of four patients demonstrated a benefit using Botulinum toxin-A to treat delayed onset PCH, but more research is needed, similar to the other treatments.[1]

• Post-surgical cerebrospinal fluid leak
• Hydrocephalus
• Intracranial hemorrhage
• Other headache types including cervicogenic, tension, cluster, and migraine
• A medication-overuse headache
• Meningitis or other infection
• Temporomandibular joint disorder

• PCH appears in over two-thirds of patients undergoing the procedure. 
• Diagnosis is made primarily through the use of ICHD 3-beta criteria.
• Risk factors include a choice of surgical approach and length of surgery. 
• Anxiety and depression may exacerbate symptom intensity.
• Management in the acute phase may be best guided by the treatment of headaches of a similar phenotype.
• Management in the chronic phase may best be achieved through non-pharmaceutical adjuncts.

Post craniotomy is quite common after surgery, but making the diagnosis is difficult as there are many serious causes of headaches post craniotomy, which first needs to be ruled out. The condition is best managed by an interprofessional team that includes a neurosurgeon, neurologist, internist, pharmacist, and a mental health nurse. Once the severe causes have been ruled out, it is best to use non-pharmacological therapy to relieve the headaches. The use of narcotics in post craniotomy patients is not recommended. Psychotherapy or some cognitive-behavioral therapy may be useful.