Bon-Jour Lin

Correlation between magnetic resonance imaging grading and pathological grading in meningioma

OBJECT This study investigated the specific preoperative MRI features of patients with intracranial meningiomas that correlate with pathological grade and provide appropriate preoperative planning. METHODS From 2006 to 2012, 120 patients (36 men and 84 women, age range 20-89 years) with newly diagnosed symptomatic intracranial meningiomas undergoing resection were retrospectively analyzed in terms of radiological features of preoperative MRI. There were 90 WHO Grade I and 30 WHO Grade II or III meningiomas. The relationships between MRI features and WHO histopathological grade were analyzed and scored quantitatively. RESULTS According to the results of multivariate logistic regression analysis, age ≥ 75 years, indistinct tumorbrain interface, positive capsular enhancement, and heterogeneous tumor enhancement were identified factors in the prediction of advanced histopathological grade. The prediction model was quantified as a scoring scale: 2 × (age) + 5 × (tumor-brain interface) + 3 × (capsular enhancement) + 2 × (tumor enhancement). The calculated score correlated positively with the probability of high-grade meningioma. CONCLUSIONS This scoring approach may be useful for clinicians in determining therapeutic strategy and in surgical planning for patients with intracranial meningiomas.

Progressive kyphosis after vertebroplasty in osteoporotic vertebral compression fracture.

Study Design. A single-center retrospective study. Objective. To identify the relevant incidence and risk factors of delayed vertebral collapse and progressive kyphosis with spinal canal encroachment after percutaneous vertebroplasty (PVP) for vertebral compression fracture (VCF). Summary of Background Data. Delayed vertebral collapse and progressive kyphosis with spinal canal encroachment are complications after PVP for VCF. Methods. Between December 2002 and February 2011, 843 patients underwent PVP for VCFs for at least 2 years of minimum follow-up term in a tertiary referral center. All imaging measurements were obtained digitally, with comparisons of the Cobb angle and spinal canal stenosis on fractured vertebral level at 3 different time points of pre- and postvertebroplasty, and before revision surgery. Results. Thirteen patients (14 fractures) who underwent PVP had delayed vertebral collapse and progressive kyphosis on the level of the fractured vertebra, 3 were male and 10 female, with a median age of 75 years (range, 66–89 yr). One had 2-level VCFs. All were treated with revision surgery of decompressive laminectomy for spinal canal stenosis with neurological complications. Twelve patients had additional instrument fixation. The involved vertebras were concentrated at the thoracolumbar junction region (T11–L2). The mean Cobb angles were measured at 23.67° before PVP, 15.90° after PVP, and 30.92° before revision surgery. The ratio of spinal canal stenosis was 35.45% and 49.48% before PVP and revision surgery, respectively. The occurrence rate of delayed complications was about 1.5% (13/843). Conclusion. Conservative treatment and minimal invasive vertebral augmentation surgery can be selected from patients with stable VCFs. Close follow-up is warrant to monitor the occurrence of late collapse with neurological complications. Level of Evidence: N/A

Pituitary abscess following expanding sphenoid sinus pyocele: Complication of endoscopic endonasal transsphenoidal surgery

Sphenoid sinus mucocele is a rare complication of endoscopic ndonasal transsphenoid surgery [1]. Sphenoid sinus pyocele s defined as secondary infection of sphenoid sinus mucocele ith bacterial colonization. If the clinical diagnosis is incorrect r delayed, several serious complications may occur, especially scending intracranial extension with central nervous system nfection [2]. Most patients with sphenoid sinus pyocele respond ell to broad-spectrum antibiotics and nasal decongestants. Surical intervention is only indicated for those who are refractory to edical treatment [2]. Pituitary abscess secondary to expanding sphenoid sinus infecionwas reported by few literature, and history of previous surgery or pituitary lesions may further increase its risk [3]. For patient ith sphenoid sinus mucocele/pyocele, aggressive surgical interention is recommended.

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.

Intradural Cement Leakage After Percutaneous Vertebroplasty.

Intradural cement leakage after percutaneous vertebroplasty (PV) is a rare clinical picture. We report a 64-year-old woman with osteoporotic compression fracture of the L2 vertebral body developing monoparesis and monoparesthesia after PV. The diagnosis of intradural cement collection with spinal cord damage was evidenced by clinical and neuroradiographic investigation. After decompressive surgery, the patient showed gradual improvement. This report highlights the postulated mechanism of intradural cement collection after PV and advocates some intraoperative skills to avoid this complication. In order to get a satisfactory clinical outcome, we suggest early decompressive surgery for those patients having symptomatic intradural cement leakage after PV.

Differences in Nicotine Encoding Dopamine Release between the Striatum and Shell Portion of the Nucleus Accumbens

The aim of this work was to determine the effect of nicotine desensitization on dopamine (DA) release in the dorsal striatum and shell of the nucleus accumbens (NAc) from brain slices. In vitro fast-scan cyclic voltammetry analysis was used to evaluate dopamine release in the dorsal striatum and the NAc shell of Sprague–Dawley rats after infusion of nicotine, a nicotinic acetylcholine receptor (nAChR) antagonist mecamylamine (Mec), and an α4β2 cholinergic receptor antagonist (DHβe). DA release related to nicotine desensitization in the striatum and NAc shell was compared. In both structures, tonic release was suppressed by inhibition of the nicotine receptor (via Mec) and the α4β2 receptor (via DHβe). Paired-pulse ratio (PPR) was facilitated in both structures after nicotine and Mec infusion, and this facilitation was suppressed by increasing the stimulation interval. After variable frequency stimulation (simulating phasic burst), nicotine infusion induced significant augmentation of DA release in the striatum that was not seen in the absence of nicotine. In contrast, nicotine reduced phasic DA release in NAc, although frequency augmentation was seen both with and without nicotine. Evaluation of DA release evoked by various trains (high-frequency stimulation (HFS) 100 Hz) of high-frequency stimulation revealed significant enhancement after a train of three or more pulses in the striatum and NAc. The concentration differences between tonic and phasic release related to nicotine desensitization were more pronounced in the NAc shell. Nicotine desensitization is associated with suppression of tonic release of DA in both the striatum and NAc shell that may occur via the α4β2 subtype of nAChR, whereas phasic frequency-dependent augmentation and HFS-related gating release is more pronounced in the striatum than in the NAc shell. Differences between phasic and tonic release associated with nicotine desensitization may underlie processing of reward signals in the NAc shell, and this may have major implications for addictive behavior.

Role of Post-Decompressive Hydrocephalus in Patients with Malignant Cerebral Infarction.

AIM The association between post-decompressive hydrocephalus and clinical neurological expression is still unclear. In order to investigate this relationship, the authors analyze series of ventricular morphology and level of consciousness at different clinical stages for patients accepting decompressive craniectomy (DC). MATERIAL AND METHODS From 2005 to 2011, 13 patients accepting DC under the diagnosis of malignant cerebral infarction were retrospectively evaluated in terms of ventricular frontal horn dilatation and level of consciousness, Glasgow Coma Scale score, at four different clinical stages: 1): pre-DC stage; 2): post-DC stage while stabilization; 3): post-cranioplasty stage; 4): post-shunt stage [for those with permanent cerebrospinal fluid (CSF) diversion]. RESULTS All 13 patients had ventricular dilatation and two of them had extra-axial CSF collection. Restoration of ventricular dilatation was not observed in all patients after bone flap placement, but extra-axial CSF collection resorbed spontaneously. Four patients accepting permanent CSF diversion had no improvement over neurological expression. Otherwise, two of them complicated with subdural effusion after shunt placement. CONCLUSION Decompressive craniectomy itself would lead to ventricular dilatation universally. There is no direct association between degree of ventriculomegaly and neurological expression. Permanent CSF diversion surgery as treatment for ventriculomegaly makes no clinical improvement with possible complications of overshunting.