Is vasospasm requisite for posterior leukoencephalopathy in patients with primary thunderclap headaches?

Primary thunderclap headache (TCH) is sometimes associated with cerebral vasospasm. However, the role of vasospasm in relation to the development of reversible or irreversible posterior leukoencephalopathy among patients with primary TCH has never been fully addressed. This paper includes a report on a 51-year-old woman with primary TCH complicated with posterior leukoencephalopathy and a literature review of 16 further patients with the same illness. Their magnetic resonance or conventional angiographic findings were clearly described. Our review found that all these 17 patients showed evidence of cerebral vasospasm. Eleven (65%) of them developed permanent ischaemic infarctions, almost exclusively located at the watershed zones. We suggest that the presence of vasospasm might be requisite for posterior leukoencephalopathy as well as for permanent infarctions in these patients. Therefore, searching for any clue of vasospasm is mandatory in treatment of patients with primary TCH. Absence of an accompanying vasospasm might predict a good outcome.     

Reduction in hypothalamic 1H-MRS metabolite ratios in patients with cluster headache

OBJECTIVE: To determine the 1H-MR spectroscopic (MRS) findings in the hypothalamus in patients with episodic cluster headache. METHODS: 47 patients were recruited with episodic cluster headache (35 in cluster period and 12 in remission), 21 normal controls, and 16 patients with chronic migraine. The hypothalamic 1H-MRS metabolite ratio changes in patients with cluster headache were evaluated and compared with results in the normal controls as well as patients with chronic migraine. Seven patients in the cluster period group underwent a follow up hypothalamic MRS study five to six months after remission. RESULTS: In patients with cluster headache, the hypothalamic N-acetylaspartate (NAA)/creatine (Cr) and choline (Cho)/Cr ratios were similar between those in cluster period and in remission. As a group, both NAA/Cr and Cho/Cr levels were significantly lower in patients with cluster headache in comparison with either the control or chronic migraine groups. In those with a follow up MRS study, the levels of metabolite ratios did not differ between the cluster and remission periods. CONCLUSIONS: This study provides evidence of persistent biochemical change of the hypothalamus in patients with episodic cluster headache. Low levels of NAA/Cr and Cho/Cr suggest that cluster headache might be related to both neuronal dysfunction and changes in the membrane lipids in the hypothalamus.     

Neuroradiological findings in atypical teratoid/rhabdoid tumor of the central nervous system

PURPOSE: To evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) findings of atypical teratoid tumor/rhabdoid tumor (AT/RT) of the central nervous system (CNS). MATERIAL AND METHODS: Twenty cases of CNS AT/RT have been found over the past 23 years in our hospital; these involving 11 boys and 9 girls whose mean age at diagnosis was 5.5 years. Their clinical data, the CT, and MRI findings were reviewed retrospectively. RESULTS: AT/RT was located in the cerebellum in 15 cases. Four cases arose from the supratentorial region, while only one occurred primarily in the lumbar spinal cord. Almost all cases revealed heterogeneous intensity and heterogeneous enhancement. Peripheral cystic components were common. Survival time ranged from 2 months to 3 years, with a mean survival of 11.6 months. CONCLUSION: Most cases of AT/RT are located in the cerebellum. The radiologic manifestations are non-specific. The diagnosis mainly depends on the pathologic findings. However, AT/RT should still remain in the differential diagnosis of brain tumors in young children, especially those located in the cerebellar hemisphere and with eccentric cysts.     

Imaging of invasiveness of pituitary adenomas

The purpose of our study was to examine the tumor size, imaging invasiveness of the pituitary macroadenomas (PMA) and to evaluate the directions of PMA spread. One hundred and thirty-five patients with PMA were examined with MRI and/or CT for pre-operative evaluation. We retrospectively reviewed the CT and MRI to identify tumor size, extension and to evaluate the directions of tumor spread. One hundred and seventeen patients (87%) had suprasellar extension with compression of optic apparatuses, twelve patients (9%) had extension of tumor upward to hypothalamus and third ventricle. Infrasellar extension via the floor of the sella and sphenoid sinus was found in thirty-eight patients (28%), and further downward extension to ethmoid sinus, nasopharynx and/or skull base was depicted in five patients (4%). Twenty-two patients (16%) had lateral invasion to the cavernous sinus and associated cranial nerves. Temporal and frontal extensions were depicted in seven patients (5%) and six patients (4%), respectively. Five patients (4%) had posterior subtentorial extension to posterior fossa. Histologically, only two patients showed microscopic invasive features. There was no correlation between histologic features and imaging invasiveness. The PMA had the potential of multi-directional extension. This experience indicated any type of pituitary adenoma could invade surrounding structures. Suprasellar invasion was the most common direction of pituitary adenoma spread, followed by infrasellar, lateral, anterior and posterior routes.     

Brainstem 1H-MR spectroscopy in episodic and chronic migraine

The pathogenesis of evolution from episodic migraine (EM) to chronic migraine (CM) has not yet been clearly determined. Some studies revealed that dysfunction of the brainstem may play a role. We aimed to determine the brainstem ¹H-MR spectroscopic (MRS) findings in episodic and chronic migraine. We recruited patients with EM, CM and controls. Patients with CM were divided into subgroups with and without medication overuse (MO). The ¹H-MRS metabolite ratios at the periaqueductal gray (PAG) and bilateral dorsal pons were measured and compared with those in controls. A total of 19 patients with EM, 53 patients with CM (with MO n = 30, without MO n = 23) and 16 control subjects completed the study. Patients with EM had the highest N-acetylaspartate (NAA)/creatine (Cr) ratio at the dorsal pons (right, P = 0.014; left, P = 0.034) in comparison with those of CM and controls. The latter two groups did not differ. Among migraine patients, NAA/Cr ratios at dorsal pons were inversely correlated with headache frequency (right, r = −0.350, P = 0.004; left, r = −0.284, P = 0.019) and intensity (right, r = −0.286, P = 0.019; left, r = −0.244, P = 0.045), but not disease duration. In contrast, the metabolite ratios did not differ at the PAG among the study groups. Of note, MO was not associated with brainstem MRS ratios in patients with CM. The increased NAA/Cr levels may suggest neuronal hypertrophy at the dorsal pons in EM. A progressive dysfunction of this region may occur from EM to CM since the levels declined with increasing headache frequency and intensity.     

Spontaneous intracranial hypotension presenting as mental deterioration

A 55-year-old woman had new onset of postural headache followed by change of mental status 3 weeks later. Magnetic resonance imaging (MRI) of the brain and whole spine showed typical spontaneous intracranial hypotension (SIH) findings, bilateral subdural hematoma, and cerebrospinal fluid leakage over the T7-T9. Her headache and mentality improved after epidural blood patches. Early recognition and correct diagnosis are crucial for successful treatment in patients with SIH presenting with mental confusion.     

Gamma knife radiosurgery for the treatment of recurrent seizures after incomplete anterior temporal lobectomy

To evaluate the efficacy and safety of gamma knife radiosurgery (GKS) in treating temporal lobe epilepsy, GKS was performed in four adult patients with recurrent complex partial seizures who underwent incomplete anterior temporal lobectomy (ATL) but were reluctant to undergo a second resective surgery. A marginal dose of 24.5–25 Gy, corresponding to 65–70% isodose curve, was delivered to the treatment target that included the residual amygdala and the head and anterior body of the hippocampus.None of the patients had severe acute side effects but three patients had radiation-induced MRI signal changes around the target volume 13, 20, and 24 months after GKS, respectively. All four patients had significant seizure reduction during the first 6-month period and clinical efficacy persisted throughout the 2-year follow-up period. All of the patients also had improved neuropsychological profiles, including memory function and quality-of-life, compared to their pre-GKS conditions.In conclusion, the safety and clinical efficacy of GKS make it a reasonable and suitable therapeutic alternative for patients with recurrent seizures after incomplete ATL. A higher marginal dose of >25 Gy and wider coverage may be more clinically beneficial but warrant further investigation.     

Sequential MRI studies of a patient with complex partial status--a case report

Complex partial status (CPS), the status epilepticus of complex partial seizure, is rarely seen in clinical practice. The clinical presentations of CPS are characterized by confusion, slowness in response, together with stereotypic or complex automatisms and occasional secondary generalization. The electroencephalographic findings of CPS reveal characteristic focal epileptiform activities of mesial temporal region. Magnetic resonance image (MRI) is the imaging method of choice for studying epilepsy, particularly when focus is in the temporal lobe. We report a 49-year-old female with diagnosis of viral encephalitis and clinical presentation of CPS. We present the sequential brain MRI findings at acute, subacute and chronic stages of this patient.