ABC/2 formula for "bedside" postoperative pneumocephalus volume measurement.

BACKGROUND: Postoperative pneumocephalus is associated with a higher risk of recurrence of chronic subdural hematoma (cSDH). However, there is no verified simple way to measure the pneumocephalus volume at the bedside for daily clinical use. The ABC/2 method was shown to be a simple and reliable technique to estimate volumes of intracranial lesions, such as intracranial hematomas. This study aims to evaluate the accuracy of the ABC/2 formula in estimating volumes of pneumocephalus, as compared to the gold standard with computer-assisted volumetric analysis. METHODS: A total of 141 postoperative computed tomographic (CT) brain scans of cSDH patients with burr-hole drainage were analysed. Pneumocephalus volume was measured independently by both the ABC/2 formula and the computer-assisted volumetric measurement. For the computer-assisted measurement, the volume of the air was semiautomatically segmented and calculated by computer software. Linear regression was used to determine the correlation between the ABC/2 method and computer-assisted measurement. RESULTS: The postoperative pneumocephalus volume after bilateral burr-hole drainage was significantly larger than that of unilateral burr-hole drainage (29.34 ml versus 12.21 ml, p < 0.001). The estimated volumes by the formula ABC/2 significantly correlated to the volumes as measured by the computer-assisted volumetric technique, with r = 0.992 (p < 0.001). The Pearson correlation coefficient is very close to 1, which signifies a very strong positive correlation, and it is statistically significant. CONCLUSIONS: An excellent correlation is observed between the ABC/2 method and the computer-assisted measurement. This study verified that the ABC/2 method is an accurate and simple "bedside" technique to estimate pneumocephalus volume.

Univariate and Multivariable Analyses on Independent Predictors for Cervical Spinal Injury in Patients with Head Injury.

OBJECTIVE: This study aims to identify independent factors associated with cervical spinal injuries in head-injured patients. The extent of injuries to other body parts was assessed by the Abbreviated Injury Scale (AIS) and was included in the analysis. METHODS: Consecutive head-injured patients admitted via the emergency department from January 1, 2014 to December 31, 2016 were retrospectively reviewed. The inclusion criteria were head-injured patients with an Abbreviated Injury Scale (AIS) score ≥2 (i.e., head injuries with intracranial hematoma or skull fracture). Patients with minor head injuries with only scalp abrasions or superficial lacerations without significant intracranial injuries (i.e., head injury AIS score = 1) were excluded. The primary outcome was to identify independent predictors associated with cervical spinal injuries in these head-injured patients. Univariate and multivariable analyses were conducted. RESULTS: A total of 1105 patients were identified. Of these patients, 11.2% (n = 124) had cervical spinal injuries. Univariate and multivariable analyses identified male gender (P = 0.006), the presence of thoracic injury (including rib fracture, hemothorax, or pneumothorax) (P = 0.010), and hypotension with systolic blood pressure <90 mm Hg on admission (P = 0.009) as independent predictors for cervical spinal injury in head-injured patients. CONCLUSIONS: This study showed that about 1 in 10 patients with significant head injury had cervical spine injury, usually associated with fracture or dislocation. Male gender, the presence of thoracic injury, and hypotension on admission were independent risk factors associated with cervical spinal injuries.

Cryostored autologous skull bone for cranioplasty? A study on cranial bone flaps' viability and microbial contamination after deep-frozen storage at -80°C.

Craniectomy is a life-saving procedure. Subsequent cranioplasty with autologous skull bone has a bone resorption rate from 4% to 22.8% and an infection rate from 3.3% to 26%. There are concerns with their viability and the potential microbial contamination as they were explanted for a long period of time. Eighteen cranial bone flaps stored at Prince of Wales Hospital Skull Bone Bank during the period from June 2011 to March 2016 were identified. Ethics approval was obtained. Bone chips and deep bone swabs were collected for osteoblast culture and microbial culture. Skull Bone Bank was kept at -80°C under strict aseptic technique during the study period. The storage period ranged from 4months to 55months. For the osteoblast culture, all eighteen bone flaps had no viable osteoblast growth. For the bacterial culture, five had positive bacteria growth (27.8%). Three were Pasteurella multocida and two were Methicillin-resistant Staphylococcus aureus. The mean duration of storage of the infected bone flap was 32.9months (±15.1months) versus 19.9months (±17.9months) of those bone flaps with no bacterial growth (p=0.1716). The mean size of the infected versus non-infected bone flaps was 117.7cm2 (±44.96cm2) versus 76.8cm2 (±50.24cm2) respectively (p=0.1318). Although in this study statistical significance was not reached, it was postulated that infected bone flaps tended to be larger in size and had a longer duration of storage. In conclusion, cryostored skull bone flaps beyond four months showed no viable osteoblasts. Bacterial contamination rate of bone flaps was 27.8% in this study.

Use of subdural drain for chronic subdural haematoma? A 4-year multi-centre observational study of 302 cases.

Chronic subdural haematoma (CSDH) is a common neurosurgical condition and is more prevalent in the ageing population. Studies have suggested that placement of subdural drains after burr-hole drainage was associated with lower recurrence rates. However, a considerable proportion of surgeons remained unconvinced of the effectiveness of drain placement and concerns exist with the potential complications this additional manoeuvre entails such as infection or bleeding. The aim of the present study is to evaluate the impact of subdural drain on CSDH recurrence and its safety. This is a multicentre observational study. Data of consecutive patients with burr-hole drainage performed for CSDH in three hospitals in Hong Kong during a four-year period from January 2008 to December 2011 were prospectively collected and retrospectively analysed. The primary outcome was symptomatic recurrence requiring re-operation. Secondary outcomes included the modified Rankin scales (mRS), morbidity and mortality at six months. A total of 302 patients were identified. The recurrence rate was 8.72% (13/149) with drain placement versus 16.3% (25/153) with no drain (Odds Ratio=0.489, 95%CI 0.240-0.998; p=0.0463). Local wound infection, subdural empyema, acute subdural haematoma and other complications had no significant difference. Six-month mRS, 30-day mortality and six-month mortality were comparable in both groups. In conclusion, the use of subdural drain significantly reduced recurrence with no significant increase in complications.

The use of atorvastatin for chronic subdural haematoma: a retrospective cohort comparison study.

Chronic subdural haematoma (CSDH) is a common neurosurgical condition. Burr-hole for drainage is an effective treatment. However, recurrence can be up to 8-33% and is associated with morbidities and mortalities. The underlying pathogenesis was postulated to be localised inflammation and pathological aberrant vessels formation. Atorvastatin, an HMG-CoA reductase inhibitor, is a type of lipid-lowering medication. In animal studies and a preliminary clinical trial, Atorvastatin was shown to be effective in the treatment of CSDH. It was found to inhibit inflammation and promote vascular maturation at the neomembrane of CSDH. Our study aimed to investigate the efficacy of Atorvastatin in CSDH. During the study period from January to December 2014, Atorvastatin was used in 12 CSDH patients with Glasgow Coma Scale (GCS) 13-15 or Markwalder's Grading Scale (MGS) Grade 0-2. They were retrospectively compared with GCS- and MGS-matched controls who had not used statin. Improvement with haematoma resolution at 3 months was 75% (9/12) for the Atorvastatin group, versus 42% (5/12) for the Control group (p = 0.0977). The risk of deterioration requiring burr-hole drainage was 16.7% (2/12) in the Atorvastatin group, versus 58.3% (7/12) in the Control group (p = 0.0447). The Odds Ratio (OR) of deterioration requiring burr-hole drainage with Atorvastatin was 0.143 (95%CI: 0.021-0.958), which favours the use of Atorvastatin in CSDH (p = 0.0451). The Number needed to treat (NNT) was 2.4 (p = 0.0447; 95%CI: 1.31-14.93). In conclusion, this retrospective cohort comparison study has shown that CSDH with Atorvastatin had a lower rate of deterioration and burr-hole drainage.

Intracranial aneurysm size responsible for spontaneous subarachnoid haemorrhage.

INTRODUCTION: It has been theorised that the relationship between smaller body size and smaller ruptured intracranial aneurysms in Asians indirectly supports the treatment of small, unruptured intracranial aneurysms. There has also been uncertainty regarding whether the progress that has been made in neuroimaging allows for better detection of smaller ruptured intracranial saccular aneurysms. Therefore, we conducted this systemic review of ruptured intracranial saccular aneurysm sizes according to region and time. MATERIAL AND METHODS: Computerised MEDLINE and PubMed searches of the literature for population-based studies of ruptured intracranial saccular aneurysms were carried out from 1 January 1980 to 1 March 2011. Statistical analyses were generated using SPSS for Windows, Version 15.0 (SPSS Inc., Chicago, IL) and Comprehensive MetaAnalysis 2.0 for Windows (Biostat, Englewood, NJ). The results of the meta-analyses are presented with 95% confidence intervals (CIs). RESULTS: Six eligible population- or hospital-based studies were analysed. The percentage of ruptured intracranial aneurysms measuring less than 5 mm was 28.4% (95% CI: 18.1% to 41.6%, I(2) = 98%). The percentage of ruptured intracranial aneurysms measuring less than 10 mm was 76.7% (95% CI: 69.2% to 82.9%, I2 = 89%). A higher proportion of patients with ruptured intracranial aneurysms of less than 5 mm was found in Asia compared to other regions. Similarly, a higher proportion of patients with ruptured intracranial aneurysms of less than 10 mm was found in Asia compared to other regions. CONCLUSIONS: The present findings suggest that ruptured intracranial aneurysms are smaller in Asians and should be confirmed in future prospective international multi-centre registries to assess ethnicity. Whether these findings support treating smaller unruptured intracranial aneurysms in Asians should be investigated.

Ultra-early (within 24 hours) aneurysm treatment after subarachnoid hemorrhage.

BACKGROUND: The timing of definitive aneurysm treatment (coiling or clipping) in acute aneurysm subarachnoid hemorrhage was a subject of controversy. Although most vascular neurosurgeons agreed on early aneurysm treatment (within the first 72 hours), whether ultra-early aneurysm treatment (within the first 24 hours) was beneficial remained debatable. We aimed to investigate whether ultra-early aneurysm treatment is associated with better neurological outcome in all patients or only good-grade patients or only poor-grade patients. METHODS: Two-hundred and seventy-six (84%) patients had hemorrhage onset time and aneurysm treatment time available for analysis. Values of P < 0.05 were taken as statistically significant, and P values between 0.05 and 0.10 were considered to be a trend. RESULTS: For the 96 poor-grade (World Federation of Neurological Surgeons grading scale 4 to 5) patients, there was a significant association between Short Form-36 mental scores and ultra-early aneurysm treatment (50 ± 10 vs. 46 ± 10, P = 0.019) and a trend toward association between ultra-early surgery and favorable neurological outcome (odds ratio 2.4 [95% confidence interval 1.0 to 6.0], P = 0.062). A reduction in clinical rebleeding (12% vs. 22%, P = 0.168) was observed in patients undergoing ultra-early aneurysm treatment. CONCLUSIONS: Aneurysm treatment performed within the 24-hour window may be associated with a better outcome and halve the clinical rebleeding risk in poor-grade aneurysmal subarachnoid hemorrhage patients.