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Small group summary Wed 9/21/16 – Secondary Headache
Case 1:
18 yo F with history of morbid obesity presents with daily headaches that started 2 months ago and
have become constant for the past one week. She has never had this type of headache before and that
the pain is diffuse and bilateral. They are associated with mild nausea and occasional blurred vision on
both sides. She notices brief ibuprofen but the headache never goes away completely. She feels relief
when she is upright and feels that it worsens when laying down to sleep at night. On exam she appears
comfortable. She has normal VS and normal standard physical and neurologic exam.
• What additional physical exam component is important to obtain in this patient presentation?
In addition to a thorough neurologic exam, the most physical exam step is to perform fundoscopy to
assess for papilledema. The patient in this scenario is presenting with classic signs and symptoms of
increased intracranial pressure – HA which is worse when laying down/bending over, coughing or
Valsalva, blurry vision, confusion, gait abnormality, nausea and vomiting. The least invasive way to
confirm elevated intracranial pressure is identify papilledema on fundoscopy. The optic nerve sheath
directly communicates with the subarachnoid space and as such transmits pressure changes in the brain
to the back of the eye where it can be visualized as a blurring of the normally sharp borders of the optic
disc. While extremely important, this physical exam step is often very difficult to perform using
nondilated direct fundoscopy. As such there are several options available: 1) dilate the eye using drops
such as tropicamide or atropine (watch for contraindications such as a history of glaucoma); 2) use a
pan-optic ophthalmoscope; 3) consult ophthalmology (preferred at our institution); 4) use ocular
ultrasound. A recent metaanalysis published in the Annals of EM found a SN of 96% and SP of 93% for
the use of ultrasound in detecting elevated ICP. The procedure is done by filling the orbit with a copious
amount of ultrasound gel, examining the eye in axial section, identifying the optic nerve sheath, and
measuring its diameter at 3mm posterior to its junction with the globe. A value of >5mm is considered
abnormal in adults, 4.5 mm in children, and 4mm in infants.
• What diagnostic evaluation for headache should be pursued?
As mentioned, the above patient is presenting with signs and symptoms of elevated intracranial
pressure. Although this patient’s presentation is most consistent with idiopathic intracranial
hypertension (IIH, pseudotumor cerebri), structural causes of elevated ICP must be ruled out in a patient
without a prior established Dx of IIH. At OSU, we have a defined algorithm for the workup of these
patients, both with a prior Dx of IIH and without. For patients without a prior Dx, the first step is
ophthalmology evaluation for assessment of papilledema. For most patients, the first step will be a
noncontrasted CT of the head to look for blood or obvious mass lesions. This is followed by an MRI brian
if one has not been performed in the past 6 months, with MRA and MRV as well if this has never been
done before. If papilledema is graded as mild to moderate and brain imaging reveals findings consistent
with IIH, the Pt’s HA can be managed symptomatically and they may be referred for outpatient
ophthalmology follow—up and LP on an outpatient basis. If the papilledema is severe, then LP is
performed in the ED, neurosurgery is consulted, and the patient is admitted to ophthalmology. In pts
with a known Dx of IIH WITHOUT a shunt, those with mild-moderate papilledema can be managed
symptomatically and discharged with optho and/or neurosurgery f/u in 3 days and LP on outpatient
basis. Those with severe papilledema should have MRI brain (if not done within 6mos), LP in the ED, and
should be admitted to ophthalmology with neurosurgery consult. For those with an established Dx of IIH
and a shunt in place, those with low pressure HA symptoms OR high pressure Sx and mild-moderate
papilledema should have an XR shunt series performed and may be managed symptomatically in the
CDU or on an outpatient basis. If high pressure Sx and severe papilledema are present, shunt series (if
not done in past month) and MRI brain (if not done in past 6mos) should be done, LP should be
performed (if Pt does not have a lumbo-peritoneal shunt), and neurosurgery should be consulted for
shunt adjustment.
Here is the link to the OSUMC clinical practice guideline:
https://evidencebasedpractice.osumc.edu/Documents/Guidelines/IIH.pdf
• Which consultants may be helpful in evaluation and treatment of this patient’s complaint?
As discussed above, ophthalmology and neurosurgery consultations are often necessary in the
management of these patients.
• Discuss treatment options for this patient.
Though the pathophysiology of IIH is poorly understood, there is a strong association with obesity. As
such, weight loss either through lifestyle modifications, pharmacologic management, or bariatric surgery
is the cornerstone of treating the underlying condition. These patients should have an established
relationship with a PCP for assistance in managing weight and consideration of bariatric surgery referral
and should be referred to a nutritionist as well. Beyond weight loss, management is focused on lowering
intracranial pressure. In the acute setting, this can be accomplished through high volume LP. Other ED
treatments include standard iv headache cocktails which may be effective for some patients. Narcotic
medications should be avoided due to lack of demonstrated benefit, high rate of rebound HAs, and
potential for dependency, increased ED visits, etc. For maintenance therapy, many patients will be placed
on acetazolamide, a carbonic anhydrase inhibitor diuretic which has equivocal evidence for benefit and
poor tolerance in many patients. Other medications such as furosemide have been used as well but have
even less evidence to support them. Surgical procedures such as optic nerve fenestration may provide
some benefit. CSF diversion through ventriculoperitoneal, lumboperitoneal, ventriculoatrial, etc shunts is
also commonly performed, though the evidence for benefit is modest at best.
Case 2:
A 20 year old female college student presents to the emergency room and reports experiencing a severe
headache. She was seen 2 days ago for fever, headache, and neck stiffness in another ED and underwent
lumbar puncture at that time that she was told was normal. Her fever has resolved, but she reports
onset yesterday of a headache that has changed in character from aching to severe, diffuse pain. It is
worse when sitting or standing and only tolerable when laying flat in bed. Physical and neurologic exam
were normal as well.
• What diagnostic evaluation of headache should be pursued in this case presentation?
This patient is presenting with a story concerning for post lumbar puncture headache (PLPH) and does
not require any further specific diagnostic workup. The important features of her Hx include recent LP
and low pressure HA, defined by worsening with upright position and improvement with laying flat.
Although post lumbar puncture meningitis has been documented due to introduction of skin flora into
the CSF during the performance of LP, it is very uncommon and in the absence of compelling symptoms
such as fevers or profound meningismus, repeat LP to rule it out need not be performed. Other post-LP
complications to be aware of include cerebral herniation or development of intracranial hemorrhage
from tearing of bridging vessels due to intracranial pressure shifts; again these complications are
extraordinarily rare. The pathophysiology of PLPH is low intracranial pressure caused by dural defect
allowing for ongoing leakage of CSF at the LP site.
• What are the risk factors for this type of headache?
Risk factors for PLPH include number of LP attempts, volume of CSF drained, and size and type of needle
used. Though classically taught that maintaining supine position for 1hr following LP can decrease the
incidence of PLPH, this has not been bourne out in the literature and a recent Cochrane review
recommends against routine use of supine positioning following LP, instead advocating for whatever
position is most comfortable for the pt. Ways to decrease the incidence of PLPH include using the
smallest caliber needle possible (a 25 or 22g needle if possible), as few attempts as is necessary,
positioning of the bevel of the needle UP (towards the ceiling when Pt is in lateral decubitus position),
taking the smallest volume of CSF necessary for the planned diagnostic testing, and using an atraumatic
needle such as the Sprotte needle, rather than the Quincke which is commonly included in LP kits (see
photo below). It should be noted however that many clinicians find the LP more difficult using the Sprotte
needle.
• Describe options for treatment of this condition.
There is moderate evidence for the use of iv caffeine in the acute treatment of PLPH. A recent systematic
review showed an absolute risk reduction of 0.61 for the use of IV caffeine which is typically dosed at
300-500mg. Oral caffeine is well-absorbed and so discharged patients can be given Rx for 300-500mg
either daily or bid for the next several days. The mechanism of action is thought to be related to
vasoconstriction of dilated intracranial blood vessels. Based on this presumed mechanism, sumatriptan
has also been advocated and has been reported effective in a few case reports but does not have strong
prospective data to support its use for this indication. Other measures aimed at replenishing the lost CSF
such as iv fluids, DDAVP, and ACTH have not been demonstrated to be effective. Typically headache
cocktails may also be tried though they have not been specifically studied. In PLPH lasting longer than
72hrs and refractory to conservative medical mgmt, consider anesthesia consultation for blood patch in
which a quantity ranging from 2-30cc of the patient’s own blood is injected into the epidural space at the
level of the LP. The theoretical origins of this practice come from the observation of decreased incidence
of PLPH following bloody taps. The injected blood forms a clot which seals off the hole in the dura,
allowing for reaccumulation of CSF and resumption of nml ICP. Success rates of beween 70-98% have
been reported.
Additional Question: How should patients undergoing lumbar puncture be counseled prior to the
procedure?
As with any procedure, the Pt should be counseled on the indications, risks, benefits, and alternatives to
the procedure. I typically begin by explaining that the LP is a very common ED procedure which is
typically well-tolerated with major complications being rare. I typically explain that the procedure is
much scarier to patients than it is dangerous and that, while tolerance of the procedure varies
considerably between patients, typically the most uncomfortable part is the injection of local anesthetic,
which is similar to when a dental procedure is performed, and that the majority of my patients do not
find it significantly more painful than PIV placement. I then go through the common complications before
moving on to rare but serious complications. The most common complications would be pain, discomfort
from the positioning, post lumbar puncture headache, and unsuccessful procedure requiring repeat
attempt under fluoroscopy. This is followed by bleeding and infection for which I recommend PLT >50k
and INR <1.6 before performing the procedure, and use of sterile technique (particularly face masks, as
the most common organisms implicated in post-LP meningitis have been oral flora). Finally I mention the
less common complications such as transient leg weakness, radicular back pain, injury to the spinal cord
(only in Pt’s with undiagnosed tethered cord), cerebral herniation (rare – only about 1% even in pts with
known elevated ICP), and aortic injury. In the case of suspected meningitis, the alternative to the
procedure would be to complete an empiric full course of IV ABX with all the unnecessary risk of ABX side
effects as well as the risk of partially treated meningitis with sterilized CSF Cx and inability to isolate a
resistant organism if LP is performed at a later time.