Ming-Ying Liu

The antinociceptive role of a bulbospinal serotonergic pathway in the rat brain

&NA; The antinociceptive role of spinal serotonin (5‐HT) neurons descending from 5‐HT cells near the ventrolateral surface of the medulla oblongata was investigated by stimulating these cells in normal rats, in rats with generalized or selective chemical ablation of 5‐HT nerves, and in rats with postsynaptic blockade of 5‐HT receptors. Electrical stimulation of the lateral medulla elicited analgesia in normal rats; the increase in pain threshold was proportional to the intensity and to the frequency of stimulation. In addition, microinjection of kainic acid or L‐glutamate at the same sites also produced analgesia. However, generalized destruction of CNS 5‐HT nerves produced by intraventricular injection of 5,7‐dihydroxytryptamine (5,7‐DHT) or selective destruction of spinal 5‐HT nerves produced by intraspinal injection of 5,7‐DHT reduced the magnitude of the antinociceptive responses to electrical stimulation. Postsynaptic blockade of CNS 5‐HT receptors produced by intraventricular injection of cyproheptadine also reduced the stimulation‐produced analgesia. The specificity of the lesions for 5‐HT nerves is demonstrated by the lack of effect on the levels of noradrenaline in the same brain regions. The results indicate that the activity of 5‐HT nerve cells adjacent to the ventrolateral surface of the medulla oblongata and projecting to the spinal cord serves to elevate pain threshold.

Intraventricular morphine produces pain relief, hypothermia, hyperglycaemia and increased prolactin and growth hormone levels in patients with cancer pain

SummaryThe effects of analgesic, thermoregulatory and endocrine functions of administering morphine sulphate (0.3mg) into the lateral cerebral ventricle via an Ommaya catheter were assessed in eight patients with cancer pain. Satisfactory control of intractable pain was obtained in these patients, without any change in other sensory modalities. The delay in the onset of pain relief and the duration of analgesia ranged, respectively, from 20 to 40 min and from 12 to 16 h after drug injection. In addition, intraventricular administration of morphine caused a reduction in rectal temperature in these patients at an ambient temperature of 24°C. The hypothermia in response to the injection of morphine was due to cutaneous vasodilation and sweating. There was no change in metabolism or in respiratory evaporative heat loss after morphine injection. Further, 10 to 20 min after intraventricular administration of morphine, the blood levels of prolactin, growth hormone and glucose were elevated in these patients. The changes in temperature and endocrine levels lasted for 1–3 h. In addition to the pain relief, these side-effects of morphine treatment were short-lasting and disappeared as the morphine treatment continued. The results indicate that activation of opiate receptors in the brain produced pain relief, hypothermia (due to cutaneous vasodilation and sweating), and increased blood levels of prolactin, growth hormone and glucose in patients with cancer pain.

CyberKnife stereotactic radiosurgical rhizotomy for refractory trigeminal neuralgia

Stereotactic radiosurgery (SRS) has been established as an option for the treatment of trigeminal neuralgia (TN). Here, we report our experience of CyberKnife®-based (Accuray, Sunnyvale, CA, USA) stereotactic rhizotomy on medically refractory patients to determine its clinical effectiveness. Between January 2007 and December 2009, 14 selected patients underwent SRS for TN at our CyberKnife Center. Patients were evaluated for pain relief using a visual analog scale (VAS) score, time to reach pain relief (latency), duration of pain control, decrease of pain medication, occurrence of new dysesthesia, and side effects at the 3-month, 6-month, 1-year and 2-year follow-up. A literature analysis revealed that compared with other SRS systems, which can provide a high rate of pain control, CyberKnife® stereotactic rhizotomy yielded an earlier onset of pain relief in our cohort.

Temozolomide-related acute lymphoblastic leukemia with translocation (4;11)(q21;q23) in a glioblastoma patient

Temozolomide (TMZ), an alkylating agent, is widely used for treating high-grade gliomas. TMZ has been reported to cause secondary myelodysplastic syndrome and acute myeloid leukemia. However, TMZ-related acute lymphoblastic leukemia is rare. Here we describe a 54-year-old woman with glioblastoma multiforme, who developed precursor-B acute lymphoblastic leukemia with translocation (4;11)(q21;q23) after 15 months of TMZ treatment.

Quantitative analysis of anatomical relationship between cavernous segment internal carotid artery and pituitary macroadenoma

Abstract Cavernous segment internal carotid artery (CSICA) injury during endoscopic transsphenoidal surgery for pituitary tumor is rare but fatal. The aim of this study is to investigate anatomical relationship between pituitary macroadenoma and corresponding CSICA using quantitative means with a sense to improve safety of surgery. In this retrospective study, a total of 98 patients with nonfunctioning pituitary macroadenomas undergoing endoscopic transsphenoidal surgeries were enrolled from 2005 to 2014. Intercarotid distances between bilateral CSICAs were measured in the 4 coronal levels, namely optic strut, convexity of carotid prominence, median sella turcica, and dorsum sellae. Parasellar extension was graded and recorded by Knosp–Steiner classification. Our findings indicated a linear relationship between size of pituitary macroadenoma and intercarotid distance over CSICA. The correlation was absent in pituitary macroadenoma with Knosp–Steiner grade 4 parasellar extension. Bigger pituitary macroadenoma makes more lateral deviation of CSICA. While facing larger tumor, sufficient bony graft is indicated for increasing surgical field, working area and operative safety.

Image analysis of open-door laminoplasty for cervical spondylotic myelopathy: Comparing the influence of cord morphology and spine alignment

OBJECTIVES Previous studies have identified the factors affecting the surgical outcome of cervical spondylotic myelopathy (CSM) following laminoplasty. Nonetheless, the effect of these factors remains controversial. It is unknown about the association between pre-operative cervical spinal cord morphology and post-operative imaging result following laminoplasty. The goal of this study is to analyze the impact of pre-operative cervical spinal cord morphology on post-operative imaging in patients with CSM. METHODS Twenty-six patients with CSM undergoing open-door laminoplasty were classified according to pre-operative cervical spine bony alignment and cervical spinal cord morphology, and the results were evaluated in terms of post-operative spinal cord posterior drift, and post-operative expansion of the antero-posterior dura diameter. RESULTS By the result of study, pre-operative spinal cord morphology was an effective classification in predicting surgical outcome - patients with anterior convexity type, description of cervical spinal cord morphology, had more spinal cord posterior migration than those with neutral or posterior convexity type after open-door laminoplasty. Otherwise, the interesting finding was that cervical spine Cobbs angle had an impact on post-operative spinal cord posterior drift in patients with neutral or posterior convexity type spinal cord morphology - the degree of kyphosis was inversely proportional to the distance of post-operative spinal cord posterior drift, but not in the anterior convexity type. CONCLUSIONS These findings supported that pre-operative cervical spinal cord morphology may be used as screening for patients undergoing laminoplasty. Patients having neutral or posterior convexity type spinal cord morphology accompanied with kyphotic deformity were not suitable candidates for laminoplasty.

Paraganglioma of the cauda equina

A 48-year-old female presented with symptoms of low back pain and radiation down the posterior aspect of both the legs of six months duration. She was not a known case of diabetes and hypertension. On admission, physical examination was unremarkable. The neurological examination revealed sensory deficits in the distribution of L4 and L5 dermatomes on both the legs. The muscle power was normal and tendon reflexes were normal. The plain X-ray of lumbar spine was normal. Magnetic resonance imaging (MRI) showed an intrathecal extramedullary well-defined tumor measuring about 2.5 3 0.7 3 1.2 in size at the level of L4-5. The tumor appeared as isointensity with respect to the spinal cord on T1-weighted sequences and hyperintensity on T2-weighted image [Figure 1a and b]. Contrast MRI showed homogenous enhancement of the tumor and also a serpiginous enhancing vascular structure extending from conus medullaris to the tumor [Figure 1c]. She underwent L4 and L5 laminectomy to remove the tumor. At operation the tumor was soft and reddish and was attached to one of the nerve roots. A single vessel along the nerve root was found entrapped into the tumor [Figure 2]. Histopahtological examination shwed, nests of tumor cells separated by a fine vascular network, representing a ‘Zellballen’ pattern [Figure 3]. Immunohistochemical staining was negative for glial fibrilary acid protein and was positive for synaptophysin and chromogranin A. In

Validation of CSF Marker to Predict Shunt-Dependence Patients after Aneurysmal SAH

Purpose: A theory of blood-CSF barrier has been postulated for interpretations of clinical diseases. The microenvironment is enriched in specific molecules following physiological rhythms. In this study, we examined the possible role of CSF transthyretin in the patients who required shunt dependences after episodes of aneurysmal subarachnoid hemorrhage (aSAH).Materials and Methods: Over a 5-year period (2004-2009), there were 147 patients (79 females and 68 males) with a mean age of 58.2 years (range from 43 to 79 years) suffered from subarachnoid hemorrhage. 81 of them (subcategorized by traumatic, aneurysmal and idiopathic groups) developed altered CSF hypodynamic state contributing to the chronic hydrocephalus. The CSF samples were collected during their first shunt surgeries. The transthyretin was quantified to validate its clinical relevance to shunt dependence.Results: The transthyretin levels in three-group patients were statistically compared. The simple linear regression analysis was applied to our proposed correlation. The Pearson correlations coefficient revealed a significantly positive result (R^2=0.72 in traumatic group and R^2=0.86 in aneurismal group). There is significantly statistical meaning for tramatic and aneurysmal patients with regard to tracing CSF transthyretin to predict the intent-to-treated hydrocephalus secondary to aSAH (Both p-value≦0.05).Conclusions: In our study, the CSF transthyretin could be a important CSF maker to correlate the clinical shunt-dependence. As specific for aneurysmal cases, a prospective randomized study is further required to verify its reliability rather than traumatic and idiopathic occasions.

Successful Staged Obliteration of Three Unruptured Cerebral Aneurysms by Clipping, Coiling, and Proximal Occlusion: Report of a Case

Endovascular techniques offer a mode of therapy alternative or adjuvant to surgery in treatment of multiple or inoperable cerebral aneurysms. Proximal arterial occlusion, with or without extracranial-to-intracranial (EC-IC) bypass, is frequently performed for inoperable cerebral aneurysms. The authors report hereby a 70-yearold woman presenting with the left cavernous sinus syndrome because of a giant inoperable internal carotid aneurysm. In addition, two other aneurysms were identified. The patient underwent staged obliteration of the three aneurysms by clipping, Guglielmi detachable coils (GDCs) embolization, and proximal internal carotid artery occlusion with golden valve balloons (GVBs). At 5-month follow-up, the cerebral angiogram showed that the left ICA aneurysm was completely obliterated, the right ICA aneurysm was totally occluded by GDCs, and the left MCA aneurysm was successfully clipped. In addition, the collateral circulation of the left hemisphere had been well reestablished. Symptoms and signs of the left cavernous sinus syndrome subsided about three months after the treatment. Triple aneurysms can be managed successfully with a combination of different therapies.