The “springform” technique in cranioplasty: custom made 3D-printed templates for intraoperative modelling of polymethylmethacrylate cranial implants

Background Manual moulding of cranioplasty implants after craniectomy is feasible, but does not always yield satisfying cosmetic results. In contrast, 3D printing can provide precise templates for intraoperative moulding of polymethylmethacrylate (PMMA) implants in cranioplasty. Here, we present a novel and easily implementable 3D printing workflow to produce patient-specific, sterilisable templates for PMMA implant moulding in cranioplastic neurosurgery. Methods 3D printable templates of patients with large skull defects before and after craniectomy were designed virtually from cranial CT scans. Both templates — a mould to reconstruct the outer skull shape and a ring representing the craniectomy defect margins — were printed on a desktop 3D printer with biocompatible photopolymer resins and sterilised after curing. Implant moulding and implantation were then performed intraoperatively using the templates. Clinical and radiological data were retrospectively analysed. Results Sixteen PMMA implants were performed on 14 consecutive patients within a time span of 10 months. The median defect size was 83.4 cm2 (range 57.8–120.1 cm2). Median age was 51 (range 21–80) years, and median operating time was 82.5 (range 52–152) min. No intraoperative complications occurred; PMMA moulding was uneventful and all implants fitted well into craniectomy defects. Excellent skull reconstruction could be confirmed in all postoperative computed tomography (CT) scans. In three (21.4%) patients with distinct risk factors for postoperative haematoma, revision surgery for epidural haematoma had to be performed. No surgery-related mortality or new and permanent neurologic deficits were recorded. Conclusion Our novel 3D printing-aided moulding workflow for elective cranioplasty with patient-specific PMMA implants proved to be an easily implementable alternative to solely manual implant moulding. The “springform” principle, focusing on reconstruction of the precraniectomy skull shape and perfect closure of the craniectomy defect, was feasible and showed excellent cosmetic results. The proposed method combines the precision and cosmetic advantages of computer-aided design (CAD) implants with the cost-effectiveness of manually moulded PMMA implants.

Traumatic infratentorial epidural haematoma: presentation and treatment outcome at the Jos University Teaching Hospital, North Central Nigeria

Background: Traumatic infratentorial epidural haematoma (TIEH), also called posterior fossa epidural haematomas when compared to their supratentorial counterparts, are very rare and their presentation nonspecific, accounting for 0.1-0.3% of all head trauma. Data on TIEH in our environment is very scanty. Our objective was to document the different presentations of TIEH and the outcome of management of these patients in our setting.Methods: This was a retrospective study of consecutive patients with head injury in whom non contrast cranial CT scan showed the presence of an infratentorial epidural haematoma and who presented to the Jos university teaching hospital between January 2012 to December 2020. The patients’ demographics, aetiology, clinical features, CT scan findings and outcome of treatment were extracted from the case folders and analysed using simple proportions.Results: There was a total of seven patients with TIEH out of a total of 308 patients with traumatic epidural haematoma, thus accounting for 2.3% of epidural haematomas in our series. All the TIEH were caused by road traffic collisions, all but one (85.7%) occurred in adults. Six (85.7%) of the patients had occipital skull fractures detected with cranial CT scan or at surgery. Two (28.6%) of the patients were managed non-operatively under close monitoring and did well. Five (71.4%) of the patients were managed surgically. There was one death, giving an overall mortality of (14.3%).Conclusions: TIEH is rare, the presentation is non-specific and early surgical decompression is lifesaving in selected patients.

Fluoroscopy comes to the rescue in anaesthesia management of a case of ankylosing spondylitis

Ankylosing spondylosis is always a challenge when patient has severe deformities to choose between general anaesthesia versus regional anaesthesia. Regional anaesthesia is always a choice either at institutionally or at smaller private hospital set ups. Schewley and colleagues compared regional versus general anaesthesia over 10 years and shown that regional anaesthesia is equally good choice.[1] There are many case reports which suggest that regional anaesthesia could be a safer option in severe Ankylosing spondylosis patients.[2] Author has managed to achieve neuraxial access by using fluoroscopy. However, interpretation of images by fluoroscopy could be difficult for anaesthetists without chronic pain management background. Also, availability of fluoroscopy could be variable as it may be busy in other theatres to be available later for surgery. Use of ultrasound to view spaces could be useful in cases with difficult neuraxial access to find the space. Most of the anaesthetists practising regional anaesthesia have expertise in using ultra-sound and also are comfortable to interpret the images. USG could also be helpful in pre-operative setting to identify and plan for central neuraxial blockade. [4] There are many case reports of use of USG guidance for neuraxial anaesthesia in such cases. [3] However, central neuraxial blocks in these patient comes with risks. The placement of epidural anaesthesia is technically difficult and is associated with an increased risk of an epidural haematoma. Wulf reported five out of 51 patients with spinal haematoma occurred in patients with AS in a comprehensive review of spinal haematoma associated with epidural anaesthesia over a 30?year period. These were related to difficult or traumatic insertion. In this his review article, he also mentions Ankylosing spondylosis as one of the risk factor for spinal or epidural haemoatoma. [5] Li et al also present a case report where patient developed epidural haematoma after epidura

Dural tear with multiple nerve root entrapment simultaneously after unstable spine injury: Intraoperative finding

Spinal cord injuries (SCIs) caused by trauma that frequently occur are dural tears and cerebrospinal fluid (CSF) leaks. They are not always detected with neuroimaging. Hence, the authors reported two cases of the dural tear with multiple nerve root entrapment after spine injury and described how managed. This case report was about two patients who had unstable spinal fractures. All patients have an asymmetrical neurological deficit. The following magnetic resonance imaging features have analyzed the presence of CSF leakage, epidural haematoma, and spine fractures. Both cases revealed intraoperative finding dural tear with multiple nerve root entrapment. We performed decompression with spinal fixation with a posterior approach, and then the patients were sent home without complication. During the follow-up period, none of the patients developed complications. The severe neurological deficit, fracture of laminar, and ligamentum flavum disruption on the MRI in patients were predictable factors in our cases.