The Clinical Syndrome
When the dura is intentionally or accidentally punctured, the potential for headache exists. The clinical presentation of post–dural puncture headache is classic and makes the diagnosis straightforward if considering this diagnostic category of headache. The diagnosis may be obscured if the clinician is unaware that dural puncture may have occurred or in the rare instance when this type of headache occurs spontaneously after a bout of sneezing or coughing. The symptoms and rare physical findings associated with post–dural puncture headache are due to low cerebrospinal fluid pressure resulting from continued leakage of spinal fluid out of the subarachnoid space.
The symptoms of post–dural puncture headache begin almost immediately after the patient moves from a horizontal to an upright position. The intensity peaks within 1 or 2 minutes and abates within several minutes of the patient again assuming the horizontal position. The headache is pounding in character, and its intensity is severe, with the intensity increasing the longer the patient remains upright. The headache is almost always bilateral and located in the frontal, temporal, and occipital regions. Nausea and vomiting and dizziness frequently accompany the headache pain, especially if the patient remains upright for long periods. If cranial nerve palsy occurs, visual disturbance may occur. Post–dural puncture headache is also known as spinal headache.
Signs and Symptoms
The diagnosis of post–dural puncture headache is most often made on the basis of clinical history rather than physical findings on examination. The neurological examination in most patients suffering from post–dural puncture headache is normal. If the spinal fluid leak is allowed to persist, or if the patient remains in the upright position for long periods despite the headache, cranial nerve palsies may occur, with the sixth cranial nerve affected most commonly. This complication may be transient, but may become permanent, especially in patients with vulnerable nerves, such as those with diabetes. If the neurological examination is abnormal, other causes of headache should be considered, including subarachnoid hemorrhage.
The onset of headache pain and other associated symptoms such as nausea and vomiting that occurs when the patient moves from the horizontal to the upright position and then abates when the patient resumes a horizontal position is the sine qua non of post–dural puncture headache ( Fig. 13.1 ). A history of intentional dural puncture, such as lumbar puncture, spinal anesthesia, or myelography, or accidental dural puncture, such as failed epidural block or dural injury during spinal surgery, strongly points to the diagnosis of post–dural puncture headache. As mentioned, a spontaneous postural headache that manifests identically to headache after dural puncture can occur after bouts of heavy sneezing or coughing and is thought to be due to traumatic rents in the dura. In this setting, a diagnosis of post–dural puncture headache is one of exclusion.
Testing
Magnetic resonance imaging (MRI) with and without gadolinium is highly accurate in helping confirm the diagnosis of post–dural puncture headache. Enhancement of the dura with low-lying cerebellar tonsils invariably is present. Poor visualization of the cisterns and subdural and epidural fluid collections also may be identified ( Fig. 13.2 ).
