Hands train the brain-what is the role of hand tremor and anxiety in undergraduate microsurgical skills?

INTRODUCTION: Physiological hand tremor occurs naturally, due to oscillations of the upper extremities. Tremor can be exacerbated by stress and anxiety, interfering with fine motor tasks and potentially impact on surgical performance, particularly in microsurgery. We investigated the link between tremor, anxiety and performance in a neurosurgical module as part of an international surgical course. METHODS: Essential Skills in the Management of Surgical Cases (ESMSC) course recruits medical students from European Union (EU) medical schools. Students are asked to suture the dura mater in an ex vivo swine model, of which the first suture completed was assessed. Questionnaires were distributed before and after the module, eliciting tremor risk factors, self-perception of tremor and anxiety. Johnson O'Connor dexterity pad was used to objectively measure dexterity. Direct Observation of Procedural Skills (DOPS) was used to assess skills-based performance. Anxiety was assessed using the Westside Test Anxiety Scale (WTAS). Tremor was evaluated by four qualified neurosurgeons. RESULTS: Forty delegates participated in the study. Overall performance decreased with greater subjective perception of anxiety (p = 0.032, rho = - 0.392). Although increasing scores for tremor at rest and overall WTAS score were associated with decreased performance, this was not statistically significant (p > 0.05). Tremor at rest did not affect dexterity (p = 0.876, rho = - 0.027). CONCLUSIONS: Physiological tremor did not affect student performance and microsurgical dexterity in a simulation-based environment. Self-perception of anxiety affected performance in this module, suggesting that more confident students perform better in a simulated neurosurgical setting.

Appraisal of the current staging system for residual medulloblastoma by volumetric analysis.

AIM: This study aims to investigate the accuracy of the current staging system of childhood medulloblastoma by using volumetric image analysis on immediate post-operative MRI scans. MATERIAL AND METHODS: Tumour volume and maximum cross area of residual medulloblastoma were measured on immediate post-operative MR scans of 37 children operated between 1999 and 2005. RESULTS: Mean preoperative volume was 32 cm(3) (range 4.5-71.9 cm(3)). Mean post-operative volume was 3.3 cm(3) (range 0-23.3 cm(3)). At mean follow-up of 50.08 months (range 6-129), 15 (40%) patients had died. Cut-off limit for residual post-operative tumour volume employed was maximum cross section of 1.5 cm(2), which corresponds to volume of 1.376 cm(3); 14 patients (38%) had no residual tumour, 7 patients (19%) had less than 1.5 cm(2) and 16 patients (43%) had more than 1.5 cm(2) residual tumour in its maximum cross section area. In three patients (8.2%) there was mismatch between the measured maximum cross section area and volume. In particular, in two patients, the cross section areas were more than 1.5 cm(2) but the residual tumour volumes were less than 1.376 cm(3) (the cross section area overestimated the residual volume) and in one case, the cross section area was less than 1.5 cm(2) but the residual tumour volume was more than 1.376 cm(3) (the cross section area underestimated the residual volume; difference statistically significant, Fisher's exact test, p < 0.01). CONCLUSIONS: It appears that volumetric measurement of residual medulloblastoma on immediate post-operative MRI scans may further improve the accuracy of staging process.

Spontaneous pediculolysis with associated contralateral laminar fracture. A case report.

The authors report the case of a 38 year-old female with a rare combination of spontaneous pediculolysis with an associated contralateral laminar fracture of the lumbar spine. Multimodal radiological examinations of the whole lumbar spine are recommended in the case of a symptomatic patient with low back pain who is not responding to basic physiotherapy and pain management modalities. This will provide the unsuspecting clinician a method to diagnose this rare cause of low back pain and avoid unnecessary surgical intervention.

Spontaneous extra-axial intracranial hemorrhage followed by thrombosis in congenital afibrinogenemia: perioperative management of this rare combination.

BACKGROUND: Although congenital afibrinogenemia can commonly present with hemorrhage from the umbilical cord at birth, or with spontaneous mucosal or intracranial hemorrhage in the neonatal period, life-threatening intracerebral hemorrhage in adults is infrequent. CASE DESCRIPTION: We report a 32-year-old woman with congenital afibrinogenemia. Postoperatively, she developed bilateral pulmonary emboli despite the fact that her INR was elevated to 2.3. Highly purified fibrinogen concentrate infusion may have partly contributed to this complication. An inferior vena caval filter was used successfully to prevent further pulmonary emboli. CONCLUSIONS: Spontaneous intracerebral hemorrhage must be included in the differential diagnosis in patients with known afibrinogenemia presenting with symptoms suggesting raised intracranial pressure. Immediately after surgery, intracranial pressure monitoring of patients is mandatory to pick up further intracranial bleeding early. Fibrinogen replacement therapy is recommended before surgery, but its use as a long-term prophylaxis against hemorrhage should be weighed against the risk of thrombosis.

Predictive value of preoperative ventricular volume on the need for permanent hydrocephalus treatment immediately after resection of posterior fossa medulloblastomas in children.

OBJECT: In this study, the authors investigated whether preoperative ventricular volume can be used to predict the need for permanent treatment of hydrocephalus in children with posterior fossa medulloblastomas. METHODS: Ventricular volumes were measured on magnetic resonance imaging studies obtained preoperatively and immediately postoperatively in 20 children who had undergone resection for medulloblastomas between 1999 and 2007. Comparison of mean values was performed using the one-way analysis of variance test. The association between ventricular and tumor volume was also investigated. RESULTS: All patients had obstructive hydrocephalus preoperatively, and 4 patients required postoperative shunt placement. The mean preoperative ventricular volume was 252 ml for those who required shunt placement, and 106 ml for those who did not (p = 0.000). The postoperative ventricular volume was 157 and 78 ml, respectively (p = 0.039), larger than normal in both groups. The mean postoperative and preoperative ratios were 0.69 and 0.70, respectively (p = 0.932). There was no correlation of ventricular volumes with age at operation (older or younger than 3 years), presence of metastasis, or amount of residual tumor. There was a statistical correlation between the preoperative ventricular volume and the tumor volume, related to the need for permanent shunt placement. CONCLUSIONS: Preoperative ventricular volume has predictive value for the later need for shunt placement, but in clinical practice this may be difficult to appreciate because all patients have significant hydrocephalus at presentation. The rate of ventricular size reduction in response to tumor excision does not have predictive value because ventricular volume is related to tumor volume. It appears that the removal of cerebellar medulloblastoma converts hydrocephalus from obstructive to communicating, which requires surgical treatment if it exceeds a certain level of cerebrospinal fluid volume.

Non-hodgkin lymphoma presenting with tetraparesis in a 3-year-old child.

INTRODUCTION: Spinal cord compression (SCC) is a rare presentation of non-Hodgkin lymphoma (NHL) which requires early diagnosis and prompt treatment to avoid devastating events and permanent neurological deficits. MATERIAL: We report a 3-year-old boy with a history of rapidly progressive tetraparesis. MRI revealed a large mass in the left side of the neck extending from the skull base into the supraclavicular fossa with extra- and intra-dural extension of this mass, causing cervical SCC from C1/2 to C7/T1 level. Liver and right kidney lesions were present as well. A 'tru-cut' needle biopsy was performed under general anaesthetic and histological examination showed a high-grade B cell lymphoma. In light of the extensive CNS involvement, chemotherapy was commenced with prednisolone, cyclophosphamide, vincristine, doxorubicin, methotrexate, cytarabine and etoposide. Patient neurological status started to improve clinically 1 week after commencement of chemotherapy. He made good neurological recovery and after 6 months was fully mobile without any neurological deficits. Six-month MRI showed complete resolution of the intraspinal-extradural disease, which unfortunately recurred 1 year after the initial diagnosis, involving the cervical and upper thoracic spinal cord. DISCUSSION: In view of the satisfactory neurological outcome that treatment with chemotherapy can achieve, and bearing in mind the potential complications and late adverse consequences of decompressive laminectomy or radiotherapy in a very young child, biopsy of the extraspinal part of the tumour causing SCC should be considered first, before more aggressive therapeutic measures are decided.

Magnetic resonance spectroscopy suggests key differences in the metastatic behaviour of medulloblastoma.

BACKGROUND: Metastatic medulloblastoma has a poorer prognosis than localised disease in part due to inherent properties of the tumour. 1H magnetic resonance spectroscopy (MRS) provides a powerful method for investigating tumour metabolism in vivo. METHODS: Magnetic resonance imaging and short echo time (Te 30 ms) single voxel MRS were performed on the primary tumour of 16 children with medulloblastoma prior to surgical resection. Tumour volumes were calculated using a segmentation technique and the MRS was analysed using LCModel. RESULTS: Patients with metastatic disease had primary tumours which were smaller (p=0.01), had higher levels of total choline (p=0.03) and lower levels of mobile lipids (p=0.04). CONCLUSION: Metastatic medulloblastomas have metabolite profiles indicative of increased cell growth and decreased cell death compared with localised tumours reflecting intrinsic differences in underlying biology. Localised tumours with an MRS metabolite profile similar to those with metastatic disease may be at increased risk of metastatic relapse.

The Pott puffy tumor revisited: neurosurgical implications of this unforgotten entity. Case report and review of the literature.

The Pott puffy tumor is a subperiosteal abscess of the frontal bone that appears as a localized swelling of the overlying region of the forehead associated with frontal osteomyelitis. The authors report the case of an 11-year-old boy who presented with a 6-week history of frontal headaches and a recent sudden-onset, progressively enlarging swelling of his midline forehead associated with immediate relief of headaches. A computed tomography (CT) study revealed 1) a subperiosteal abscess with intracranial extension through the perforated posterior table of the frontal sinus and 2) a large epidural abscess overlying a compressed and narrowed superior sagittal sinus. Emergency surgical relief of the epidural abscess, curettage of the osteomyelitic bone, and excision of the periosteal granulomatous puffy lump were performed. A 6-week course of intravenous antibiotic medication was completed, and the patient had an excellent recovery. The Pott puffy tumor remains a serious complication of frontal sinusitis. In the past 5 years, the frequency of published pediatric cases has increased. Undiagnosed or partially treated frontal sinusitis may lead to this serious complication, and the apparent increase in incidence rate may suggest that this complication of frontal sinusitis could be underestimated in clinical practice. The authors conclude that early diagnosis and complete treatment of frontal sinusitis is crucial.

Risk factors for developing epilepsy after craniotomy in children.

INTRODUCTION: We performed a retrospective analysis of children undergoing supratentorial craniotomy, attempting to identify possible risk factors for postoperative epilepsy and the need for prophylactic anticonvulsant therapy. MATERIALS AND METHODS: We analysed 107 consecutive patients (55% males) who had supratentorial craniotomy for a variety of diagnoses (tumours, trauma, infection, vascular malformations and others) during 1995-1999. Mean age at operation was 89 months (range: 1-180 months). Patients who presented with epilepsy were excluded. Postoperative epilepsy was considered present if patients required systematic pharmacological treatment, at a minimum follow-up of 6 months. Linear regression was used to analyse the effect of sex, anticonvulsant prophylaxis, duration of operation, closure of dura, postoperative infection, the diagnosis, anatomical region of brain affected, operation type (craniotomy/craniectomy) and the need for brain resection. RESULTS: Prophylactic anticonvulsants were given to 52% of the patients; 97% had craniotomy; in five patients, the dura was left open; in 33%, some kind of brain tissue resection had been performed; two patients (1.8%) developed postoperative infection; one patient died. Only 13 patients (12%) developed postoperative epilepsy. The only two factors with statistical significance were female sex (p=0.045) and the absence of dural closure (p=0.001). All other factors were not significant (p>0.258). CONCLUSIONS: Postoperative epilepsy after supratentorial craniotomy is uncommon in children, incidence being 12%. The administration of prophylactic anticonvulsants does not appear to influence the risk of epilepsy. Surprisingly, females have statistically higher risk. Lack of dural closure has higher risk of epilepsy, but this may reflect the type of pathology.

Atlanto-axial rotatory fixation caused by spontaneous intracerebral haemorrhage in a child.

INTRODUCTION: Atlanto-axial rotatory fixation is rare in children and usually associated with upper respiratory tract infection or trauma. We present a patient who developed the condition acutely as a consequence of rapidly evolving hemiplegia secondary to intracerebral haemorrhage. CASE REPORT: A previously well 12-year-old boy suddenly developed left hemiparesis within 30 min. Soon after, he developed painful torticollis. On examination, a dense left hemiplegia was associated with left facial and hypoglossal weakness. On computerised tomography (CT) scan there was an intracerebral haemorrhage in the deep aspect of the right frontal lobe in the corona radiata, with extension in the ventricular system. The plain radiographs of the cervical spine, and CT scan later, confirmed the presence of C1-C2 rotatory subluxation. The haematoma was aspirated stereotactically through a burr hole, and at the same session, the subluxation was reduced by manipulation and traction of the cervical spine. The patient was treated with a hard collar. The torticollis did not recur. The hemiparesis resolved within 6 months. A subsequent magnetic resonance imaging and magnetic resonance angiography scan indicated possible arterio-venous malformation (AVM) at the site of the haemorrhage, which was confirmed with digital subtraction angiography. The AVM was surgically excised 1 year from the original haemorrhage. DISCUSSION: In the absence of any other predisposing factor, it is postulated that the acute atlanto-axial rotatory subluxation was secondary to the acute loss of muscular tone due to the acute hemiparesis. This explains that the subluxation has not recurred a year after, while the hemiparesis has completely resolved.

Removal of subdural-peritoneal shunts in infants.

INTRODUCTION: A common method of treating subdural collections is the insertion of a unilateral subdural-peritoneal shunt. In most cases, the shunt can be removed a few months later, but there is the anxiety that removal could cause complications and some surgeons elect to leave the shunts permanently implanted, on the understanding that they are not causing problems. A retrospective review was performed of patients who had their subdural shunts removed after CT evidence of resolution of the collections, with the intention of assessing the possible risks and benefits. MATERIALS AND METHODS: Of the 19 patients who had insertion of a subdural shunt for infantile subdural collections by a single surgeon between 1999 and 2003, 14 were eligible for removal of the shunt and 13 had the shunt removed, while in 1 patient the parents refused the option of removal. Mean age at shunt insertion was 9.1 months (range 1.5-25.4 months). The mean shunt implantation time was 5 months (range 0.5-11 months). The mean follow-up period was 30.3 months (range 1-59 months). RESULTS: All shunts were removed successfully without complications. There was difficulty in removing the shunt in one case (implantation time 10 months) because of migration of the shunt, requiring extension of the incision and a small craniectomy. None of the patients required re-insertion of the shunt. CONCLUSION: Subdural shunts can be removed safely, but it is advisable to perform such an operation during the first 6 months after insertion to avoid undue operative difficulties.