Optimizing and simplifying post-traumatic amnesia testing after moderate-severe traumatic brain injury despite common confounders in routine practice.

The duration of post-traumatic amnesia (PTA) following traumatic brain injury (TBI) is a key diagnostic and outcome indicator. However, concerningly, different PTA paradigms record different PTA durations: some over-estimate, others under-estimate, PTA. Thus, a compromise is implied. The potential effect of in-hospital confounders including opioids is unknown. Three clinical groups were prospectively recruited. Group-1: in-patients with moderate-severe-TBI (MS-TBI), considered likely 'in-PTA'. Group-2: patients rehabilitating after recent MS-TBI, considered 'out-of-PTA'. Group-3: orthopaedic in-patients without TBI undergoing elective surgery. Only Groups 1&3 were taking opioids. All were administered the Westmead Post-traumatic Amnesia Scale (WPTAS) and the Galveston Orientation and Amnesia Test (GOAT). Results were obtained in n = 56 (Group-1:n = 18, Group-2:n = 13 and Group-3:n = 25). On WPTAS, Groups 1&3 scored similarly, but significantly lower than, Group-2 (χ2 = 8.2, P = 0.017). Contrariwise, on GOAT, Group-1 scored significantly lower than Groups 2&3 (χ2 = 23.99, P < 0.001): however, no patient scored GOAT <75. WPTAS showed moderate sensitivity (72%) but poor specificity (40%) in distinguishing Group-1 from Groups 2&3. Contrariwise, GOAT showed 100% specificity but 0% sensitivity. WPTAS 'day of week' and 'pictures' combined with GOAT 'transport medium to hospital', 'anterograde amnesia' and 'retrograde amnesia' maximized sensitivity (100%), specificity (85-88%), PPV (77-83%) and NPV (100%) in distinguishing Group-1 from Groups 2&3. CONCLUSIONS: Confounders including opioids likely affected WPTAS overall, but not GOAT specificity. A merger, whereby WPTAS sensitivity augmented GOAT specificity, was therefore sought. Favourable items from WPTAS (4/12) and GOAT (3/10) together optimized, and yet simplified, PTA testing; despite prevalent clinical confounders. Less, not more, 'PTA' items would benefit both patients and staff alike.

Prospective randomized placebo-controlled double-blind clinical study of adjuvant dexamethasone with surgery for chronic subdural haematoma with post-operative subdural drainage: Interim analysis.

Most chronic subdural haematomas (CSDH) are successfully treated neurosurgically. However, operative recurrences occur with a frequency 3-30%, consume resources and potentially prolong length-of stay (LOS). The only adjuvant factor proven to significantly decrease CSDH recurrence rate (RR) is post-operative subdural drainage. Corticosteroids have been used to conservatively manage CSDH. One non-randomised study also compared dexamethasone (DX) as an adjunct to surgery without post-operative drainage: whilst a null effect was observed, the 'surgery-alone' group consisted of only n = 13. We present an interim analysis of the first registered prospective randomised placebo-controlled trial (PRPCT) of adjuvant DX on RR and outcome after CSDH surgery with post-operative drainage. Participants were randomised to either placebo or a reducing DX regime over 2 weeks, with CSDH evacuation and post-operative drainage. Post-operative mortality (POMT) and RR were determined at 30 days and 6 months; modified Rankin Score (mRS) at discharge and 6 months. Post-operative morbidity (POMB) and adverse events (AEs) were determined at 30 days. Interim analysis at approximately 50% estimated sample size was performed (n = 47). Recurrences were not observed with DX: only with placebo (0/23 [0%] v 5/24 [20.83%], P = 0.049). There was no significant between-group differences in POMT, POMB, LOS, mRS or AEs. CONCLUSIONS: In this first registered PRPCT, interim analysis suggested that adjuvant DX with post-operative drainage is both safe and may significantly decrease recurrences. A 12.5% point between-groups difference may be reasonable to power a final sample size of approximately n = 89. Future studies could consider adjuvant DX for longer than the arbitrarily-chosen 2 weeks.

Prospective controlled cohort study of Troponin I levels in patients undergoing elective spine surgery for degenerative conditions: Prone versus supine position.

Prior studies have suggested that elevated serum Troponin-I (TnI) levels immediately after non-cardiac surgical procedures (8-40%) represent subclinical cardiac stress which independently predicts increased 30-day mortality. Routine post-operative TnI monitoring has therefore been suggested as a standard of care. However, no prior studies have focussed on elective degenerative spine surgery, whilst few have measured pre-op TnI. Further, prolonged prone positioning could represent an additional, independent, cardiac stress. We planned a prospective controlled cohort study of consecutive TnI levels in routine elective spine surgery for degenerative spine conditions, incorporating 3 groups: 'prone<2h', 'prone>2h' and 'supine' positioning. TnI levels (>0.04µg/L) were recorded immediately pre-/post-surgery, and by 24h of surgery. N=120 patients were recruited. Complete results were obtained in 92 (39 supine, 53 prone). No significant between-groups differences were observed in demographic or cardiovascular risk factors. Validated TnI-elevation by 24h was not observed in any group. Spurious elevations were recorded in one 'prone<2h' and one 'prone>2h'. One non-ST segment myocardial infarction (STEMI) occurred on day 7 without TnI elevation by 24h (prone>2h). There was no 30-day mortality. CONCLUSIONS: Despite a lower cut-off, no validated TnI elevation was observed in any group by 24h after surgery. One non-STEMI had not been associated with TnI-elevation by 24h. Immediately peri-operative cardiac stress therefore appeared comparatively rare in patients undergoing routine elective spine surgery. Further, prone positioning did not represent an additional, independent, risk. Routine immediately post-operative TnI monitoring in elective spine surgery therefore appears unjustified. Our study highlighted several caveats regarding consecutive TnI testing.

A clinical comparison of the quadhelix appliance and the nickel titanium (tandem loop) palatal expander: a preliminary, prospective investigation.

Maxillary expansion using either a quadhelix appliance (Qx) or a nickel titanium palatal expander (Nt) was prospectively compared in 28 consecutive new patients (19 female, nine male) presenting with posterior buccal segment crossbites. Study models taken at each activation were measured to determine the mean maxillary expansion efficacy (Emax) and the mean expansion rate (m(max)) across the first molars and first premolars. Patient discomfort was assessed using visual analogue scores, and cost-effectiveness was also considered. Neither Emax nor m(max) differed significantly between Qx and Nt across either the first molars or the first premolars. However, both Emax and m(max) were significantly greater across the first molars than across the first premolars only with Qx (Emax: 8.4 +/- 0.7 mm versus 5.1 +/- 0.6 mm, P = 0.001; m(max): 0.09 +/- 0.005 mm/day versus 0.05 +/- 0.006 mm/day, P = 0.0001). In addition, greater variance was apparent in m(max) with Nt than with Qx across both the first molars and the first premolars. Overall, Qx and Nt elicited similar discomfort. However, significantly less was reported with Nt on days 6 (P = 0.04) and 7 (P= 0.03) following the second 'activation'. These preliminary results suggest that Qx and Nt are equally efficacious maxillary expanders. However, Qx expansion appeared significantly more controlled, as well as more individually predictable in expansion rate. Overall, Qx and Nt probably elicit similar discomfort, but significantly less discomfort may be seen with Nt following the second activation. Finally, because more than one appliance is invariably required with Nt, Qx expansion is potentially less costly.

Fibrous dysplasia of the cervical spine presenting as a pathological fracture.

Fibrous dysplasia (FD) is an uncommon benign fibro-osseous abnormality of bone, of unknown aetiology and equal sex incidence, which is most commonly restricted to one bone (monostotic FD: MFD, 70%). Less commonly multiple bones are affected (polyostotic FD: PFD, 27%). Vertebral involvement is uncommon (4%), but more common with PFD (7 - 24%) than MFD (1%). Of 20 cases of FD involving the cervical spine, only three have represented MFD. Unlike cases associated with PFD, all cases presented with acute neck pain without significant neurological impairment after minor trauma. We present the case of a 35-year-old male with MFD who developed a pathological fracture of C3 following minor trauma. Radiographs showed collapse and typical 'ground glass' lucency of C3. CT revealed replacement of C3 cancellous bone by hypodense tissue extending into the right lateral mass. The cortex was thinned and fractured, and encroached upon the right foramen transversarium and spinal canal. Magnetic resonance imaging demonstrated hypo-intensity on both T1 and T2, with uniform contrast enhancement. Subtotal excision was achieved via an anterior C3 corpectomy, with residual FD left within the right lateral mass. Stability was achieved utilizing an iliac crest strut autograft, C2-4 plate-and-screws, and mobilization in a halo frame for 3 months. At 18 months, he remained asymptomatic and without deficit. Radiography, CT and MRI confirmed graft fusion without FD invasion, but with residual right lateral mass FD unchanged in size.

Persistent absence of ring-enhancement on CT with an encapsulated brain abscess.

Ring-enhancement on CT (RECT) is generally considered a sine qua non in diagnosing a cerebral abscess. We describe a 16-year-old female who presented with headaches, vomiting and drowsiness, which over 2 weeks rapidly progressed to coma. CT demonstrated a moderately large left frontal extradural abscess, associated with contiguous left frontal osteomyelitis, and underlying frontal and ethmoidal sinusitis. In addition, there was a large circular low density area within the left frontal lobe associated with midline shift that, owing to negative RECT, was assumed to represent nascent ischaemic cerebritis. Despite emergency twist-drill drainage of the extradural abscess, and antibiotic/corticosteroids administration, her clinical condition continued to deteriorate and two episodes of uncal herniation were reversed medically. Repeated CT, however, continued to demonstrate negative enhancement within the left frontal low density, although significant enhancement continued to be apparent with recurrent contiguous extradural suppuration. At definitive craniotomy, a large, well-encapsulated abscess cavity was excised from the left frontal lobe corresponding precisely to the area of previously negative enhancement, along with drainage of the recurrent extradural abscess. Thus, in addition to well-known 'false-positives' for RECT with a cerebral abscess, our case highlights the rare occurrence of a 'false-negative'. A low density mass lesion on CT with persistent negative RECT can neither be assumed to represent early cerebritis nor to exclude a mature abscess.