Transfer times and patient outcomes - A review of head injuries requiring surgery in Tasmania 2006-2017.

The Royal Hobart Hospital (RHH) provides the only neurosurgical service in the state of Tasmania, Australia, with many patients requiring surgical treatment of intracranial injuries needing to be transferred from peripheral hospitals around the state to Hobart. This retrospective review analysed the medical records of all patients who underwent a neurosurgical intervention at RHH for an intracranial injury over a 10½ year period to ascertain if prolonged transfer times correlated with poorer patient outcomes. A total of 360 patients were included in the study, with 159 patients presenting initially to a peripheral hospital and subsequently transferred to RHH for surgery. A correlation analysis found no statistically significant relationship between transfer times from peripheral hospitals and patient Glasgow Outcome Scale (GOS) scores at 6 months post-surgery (r = 0.065, P = 0.434). There was also no correlation between transfer times and discharge destination (r = 0.088, P = 0.275). We concluded that patient transfers for head injury management in Tasmania are timely and meeting patient needs.

Role of 18F-fluoro-ethyl-tyrosine Positron Emission Tomography in Investigation and Management of Suspected Gliomas.

BACKGROUND: This study aims to investigate the utility of 18F-fluoro-ethyl-tyrosine (18F-FET) positron emission tomography in surgical decision making in suspected glioma. METHODS: A retrospective review of patients undergoing 18F-FET positron emission tomography was performed. Previously published thresholds for maximum tumor background ratios (TBRs) were used for quantitative analysis. Forty-seven patients were included in the study, of whom 15 had confirmed glioma and 7 had a confirmed alternative diagnosis. RESULTS: 18F-FET showed significantly higher uptake in high-grade glioma than in nonglioma. CONCLUSIONS: Lesions with TBRmax >2.5 should be considered suspicious for glioma and biopsy considered. Threshold TBRmax >3.0 is useful for differentiating high-grade glioma from low-grade glioma. This may be a particularly useful tool for directing management in eloquent areas, such as brainstem glioma.

Hearing Improvement Following Middle Cranial Fossa Floor Defect Repair Utilizing a Modified Middle Fossa Approach and Reconstructive Techniques.

BACKGROUND: Few studies report hearing preservation following middle cranial fossa (MCF) floor defect repair. OBJECTIVE: To investigate audiological outcomes following MCF floor defect repair using a modified MCF suprapetrous approach. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. PATIENTS: Eleven patients, with MCF floor defects. INTERVENTIONS: MCF floor defect surgical repairs with either fascia or fascia and bone graft. MAIN OUTCOME MEASURED: Hearing outcomes. RESULTS: Eleven patients (two men) aged 34 to 82 years (median, 62 yrs) were identified. All patients were operated on by the same two senior surgeons (M.P. and M.G.). One patient with conductive hearing loss (based on tuning fork test) was excluded from the analysis due to missing preoperative audiogram data. All patients had middle fossa plate defects leading to cerebrospinal fluid (CSF) otorrhoea, rhinorrhoea, or meningitis. Nine patients had retrieval of herniated contents from the defect. Five patients had repair with temporalis fascia and split calvarial bone graft, and six patients had repair with fascia only. Follow up audiogram was performed at a mean 7.5 months (range, 0.5-24 mo). There was no recurrent CSF leak during the follow up period. The 10 patients (90.9%, 95% confidence interval [CI] 60.1-100.6) who had complete audiologic data sets demonstrated a mean improvement of 18.86 dB (range, -7.5 to 33.75 dB) in hearing postoperatively. One of these patients acquired a 7.5 dB reduction in postoperative hearing due to post-procedural middle ear effusion which subsequently resolved. Hearing improvement following fascial graft alone versus fascial graft with bone was 12.5 and 26.5 dB, respectively (p < 0.01). CONCLUSION: Middle fossa craniotomy with or without retrieval of herniated contents and floor reconstruction with fascia and bone is associated with improved hearing. Clinical efficacy of this technique, however, can be only fully established when a statistically meaningful number of cases have been performed.

FET PET in the evaluation of indeterminate brain lesions on MRI: Differentiating glioma from other non-neoplastic causes - A pilot study.

We aimed to determine the utility of FET PET in the management of indeterminate CNS lesions found on MRI. We performed a retrospective analysis of patients with FET PET at a single tertiary institution from 2011 to 2015. FET PET images were processed using usual methods and measurements taken including SUVmax, TBRmax, and analysis of dynamic series where available (Kipeak, Vdpeak, as well as tumor:background ratio for these variables). Correlation studies were performed using ANOVA between cohorts of high-grade histology, low-grade histology, and benign histology/stable on observation. Thirty-five patients were included, of whom 34 were suitable for analysis with median follow-up of 5 months. The positive predictive value of FET PET in this cohort was 83.3%. FET SUVmax differentiated between patients with high-grade (mean SUV 3.38, 95% CI 2.21-4.55), low-grade (1.88, 95% CI 1.33-2.43) and benign/observation (1.42, 95% CI 1.13-1.71) cohorts (p = 0.0003). Similarly, tumour to brain ratio was significant (p < 0.0001). Kipeak distinguished between high grade and observation cohorts (p = 0.036), as did KiTBR (p = 0.025). Vd peak was not significantly different in these two cohorts (p = 0.057) but Vd TBR was (p = 0.041). In conclusion, FET PET demonstrated a high positive predictive value for glioma in patients with indeterminate brain lesions on MRI. The combination of negative FET and negative FDG PET scans may predict an indolent clinical course. Confirmatory trials are needed to establish the potential value of FET PET in guiding surgical management in this cohort.

Surgical Management of Spontaneous Spinal Cerebrospinal Fluid Epidural Fistula.

BACKGROUND: Intracranial hypotension secondary to spontaneous spinal cerebrospinal fluid (CSF) fistula is a rare condition that can have serious sequelae. Early diagnosis and treatment can be challenging. CASE DESCRIPTION: We present the case of a 17-year-old male who presented with a history of sudden-onset, postural headaches associated with upper thoracic back pain. Magnetic resonance imaging (MRI) demonstrated a thoracic extradural fluid collection and slumping of the brain within the posterior fossa. The patient was initially managed with a period of bed rest, followed by a thoracic epidural blood patch. Symptoms recurred and subsequent operative exploration found a large arachnoid cyst with CSF egress through a linear split in the axilla of the right T7 nerve root. The arachnoid cyst was resected, and the defect was closed primarily. All symptoms completely resolved. MRI at 3 months postoperatively demonstrated normal spinal configuration and resolution of brain sagging. CONCLUSIONS: Spontaneous CSF leaks are a rare cause of postural headache. Although epidural blood patching is an easy and safe intervention, early serial imaging to ascertain the evolution of the pathology may identify cases that are amenable to early surgical management.