The critical role of neuroimaging in hemicrania continua: A systematic review and case series.

BACKGROUND: Hemicrania continua is a primary unilateral headache characterized by ipsilateral parasympathetic and sympathetic autonomic features. A key diagnostic criterion is its dramatic response to indomethacin treatment; however, various vascular or structural abnormalities have been reported to cause secondary hemicrania continua, presenting with clinical features similar to those of the primary headache presentation. OBJECTIVE: We reviewed the literature to compile secondary hemicrania continua cases, highlighting the importance of imaging during the evaluation. Additionally, we also contributed our three cases to the existing studies. METHODS: We conducted a review of articles from the PubMed and EMBASE databases that described reported cases of secondary hemicrania continua, covering the period from 1993 to 2021. Our review included detailed patient information, signs, and symptoms of hemicrania continua, as well as information on indomethacin usage and headache resolution (if pertinent). RESULTS: Secondary hemicrania continua can result from a remarkably diverse range of structural and vascular lesions, yet clinical reports on long-term follow-up are lacking. Notably, cases may exhibit a classical response to indomethacin, emphasizing the importance of neuroimaging in excluding secondary cases. Our search yielded 41 cases meeting our criteria. We excluded six cases that were not treated with indomethacin or were unresponsive to it. Additionally, we present three cases that highlight the necessity of neuroimaging in evaluating hemicrania continua, along with short- and long-term clinical outcomes following indomethacin and lesion-directed treatments. Case 1 presented with daily right-sided headaches and cranial autonomic symptoms. Her pain completely resolved with indomethacin use. Neuroimaging of the brain revealed a laterally directed saccular aneurysm of the right internal carotid artery. Case 2 presented with continuous left-sided unilateral headaches with superimposed exacerbations. She complained of left-sided photophobia with a dull sensation in the left ear. Her symptoms decreased after 2 weeks of indomethacin use. Neuroimaging of the head indicated a benign tumor with mass effect into the left lateral medulla and inferior cerebellar peduncle. Case 3 presented with a right side-locked headache with daily, severe superimposed exacerbations. She had photophobia in the right eye and a right-sided Horner's syndrome, along with tearing during her exacerbations. Neuroimaging of the brain revealed a pituitary tumor and her pain completely resolved with indomethacin. CONCLUSION: Hemicrania continua is a rare headache disorder that can be either primary or secondary. Importantly, response to indomethacin can still occur in secondary hemicrania continua. Thus, neuroimaging should be considered to rule out underlying structural etiology in all cases, regardless of their clinical responsiveness to indomethacin therapy.

Arachnoiditis, a complication of epidural blood patch for the treatment of low-pressure headache: A case report and systematic review.

OBJECTIVE: To report a case of arachnoiditis as a complication of epidural blood patch procedures and to systematically review the diagnostic workup, clinical outcomes, and treatment modalities reported in the literature. BACKGROUND: Epidural blood patching is an effective treatment for low-pressure headache secondary to spontaneous cerebrospinal fluid leak or iatrogenic post-dural puncture. Spontaneous intracranial hypotension is believed to be a rare headache disorder, but recently has been diagnosed at higher frequencies, making it an important differential diagnosis for intractable headaches. Arachnoiditis has surfaced as a rare complication of epidural blood patching. Symptom presentation does not always correlate with evidence of meningeal enhancement on imaging. Optimal methods for treatment remain largely unknown. METHODS: Databases Embase and PubMed were searched for all published studies on arachnoiditis post-epidural blood patch using a combination of the following medical subject headings and keywords: arachnoiditis, arachnoid inflammation, adverse event, and epidural blood patch. All original English-language articles that described arachnoid and/or meningeal inflammation in conjunction with epidural blood patch procedures were included for analysis. Title and abstract screening, data extraction, and risk of bias assessment were conducted independently and in duplicate by two reviewers. RESULTS: Seven other cases of arachnoiditis post-blood patch placement have been documented, most of which were diagnosed via magnetic resonance imaging. Six of these were a result of a spinal-epidural anesthesia for labor and delivery. Common symptoms reported were headache, back and radicular pain, paresthesia, and motor weakness. There are currently no proven consensus-based treatment recommendations available. While intravenous methylprednisolone followed by oral prednisone taper was found to be effective in the case presented, the benefit of other multi-modal therapies was unclear. CONCLUSIONS: Headache specialists who treat postural headache should be aware of arachnoiditis as a potentially severe complication of epidural blood patch. The case presented is the first of its kind to report arachnoiditis as a complication of high-volume blood patch for the treatment of spontaneous intracranial hypotension. More studies are required to determine suitable treatment options for post-epidural blood patch arachnoiditis.

Reduced Visual Quality of Life Associated with Migraine is Most Closely Correlated with Symptoms of Dry Eye.

BACKGROUND AND OBJECTIVE: Patients with migraine frequently report ocular or visual symptoms including aura, photophobia, and eye pain. Using validated instruments, our group previously reported that due to these symptoms, patients have marked reductions in visual quality of life. In chronic migraine, these reductions can be as substantial as those reported for other neuro-ophthalmic diseases such as multiple sclerosis with optic neuritis and idiopathic intracranial hypertension. Because the instruments take several different dimensions into account, we were unable to determine which ocular symptom(s) contributed to reduced visual quality of life. The purpose of this investigation was to attempt to determine which ocular symptom(s) were driving the observed reduction in visual quality of life. METHODS: We designed a cross-sectional survey-based study to assess visual quality of life, headache impact, aura, dry eye, and photophobia in migraine patients. Subjects were recruited from the Headache Clinic and General Neurology Clinic at a tertiary teaching hospital. Subjects completed validated questionnaires including: The visual functioning questionnaire-25 (VFQ-25), the headache impact test (HIT-6), the visual aura rating scale (VARS), the ocular surface disease index (OSDI), and the Utah photophobia score (UPSIS-17). Associations between VFQ-25 and OSDI, VFQ-25 and VARS, VFQ-25 and UPSIS-17, HIT-6 and OSDI, HIT-6 and VARS, and HIT-6 and UPSIS-17 were calculated. RESULTS: Of the 62 patients who completed all questionnaires, 17 had episodic migraine and 45 had chronic migraine. Twenty-three patients experienced aura and 39 did not report aura. The most striking correlations were observed between the VFQ-25 and the OSDI (-0.678; P < .001), between the HIT-6 and UPSIS-17 (0.489; P < .001), and between the HIT-6 and OSDI (0.453; P < .001). CONCLUSIONS: Dry eye seems to be the most important symptom that reduces visual quality of life and worsens headache impact. This symptom may be a form of allodynia, a well-known feature of chronic migraine. Photophobia appears to have modest effects on headache impact. In the future, we hope to determine whether treatment of dry eye symptoms can improve visual quality of life and reduce headache impact.