Patrick Statham

Cauda equina syndrome – What is the correlation between clinical assessment and MRI scanning?

The indications for magnetic resonance imaging (MRI) in suspected cauda equina syndrome, and the urgency for this investigation are regularly disputed. In this study we assess the ability of neurosurgical residents to predict on clinical grounds in which patients with cauda equina syndrome (CES) this was due to prolapsed intervertebral disc thereby justifying a request for urgent MR imaging. Design. Prospective cohort study of all adult patients with a suspected diagnosis of cauda equina syndrome. Setting. A single tertiary referral neurosurgical centre. Participants. All patients referred over a four month period with a suspected diagnosis of cauda equina syndrome. Results. MRI was normal in 10 (43%) patients. A disc prolapse causing cauda equina distortion was present in 5 (22%) patients. The diagnostic accuracy of urinary retention, urinary frequency, urinary incontinence, altered urinary sensation and altered perineal sensation were 0.57, 0.65, 0.61, 0.65 and 0.60 respectively. Conclusions. Because it is impossible in a significant proportion of patients to exclude the diagnosis of prolapsed intervertebral disc in the context of referral with suspected cauda equina compromise the authors recommend urgent MRI assessment in all patients who present with new onset urinary symptoms in the context of lumbar back pain or sciatica.

Third ventricular chordoid glioma: clinicopathological study of two cases with evidence for a poor clinical outcome despite low grade histological features

Chordoid glioma of the third ventricle is a rare glial tumour whose precise histogenesis remains uncertain. We describe two cases that presented recently to our department and review the background literature. The neoplasm tends to occur in women and its clinical presentation is variable, resulting from acute hydrocephalus or impingement upon local structures. However, the radiological appearance is distinct, with an ovoid shape, hyperdensity and uniform contrast enhancement on computerized tomography and magnetic resonance imaging. Intraoperative smear diagnosis is difficult because of the lack of specific features, although the presence of metachromatic extracellular mucin may be useful. The characteristic histological appearance is that of cords and clusters of cohesive, oval‐to‐polygonal epithelioid cells with abundant eosinophilic cytoplasm and a mucinous background. There is often a mixed chronic inflammatory infiltrate with lymphocytes and plasma cells with Russell bodies. The main differentials for histological diagnosis include chordoid meningiomas, pilocytic astrocytomas and ependymomas. An immunohistochemical panel including antibodies to glial fibrillary acidic protein, CD34, epithelial membrane antigen, pan cytokeratin, S100 and vimentin can be used to distinguish between these possibilities. Ultrastructurally the tumour cells have basal lamina and microvilli, reminiscent of ependymomas. The clinical outcome in our cases was poor because of the location of the lesion and its close relation to the hypothalamus. Limited follow‐up after surgery with or without radiotherapy suggests that as‐full‐as‐possible resection favours a better outcome, although surgery in this area carries significant operative risks.

The Halifax Interlaminar Clamp for posterior cervical fusion: Initial experience in the United Kingdom.

A retrospective review of patients who underwent posterior cervical stabilization with Halifax Interlaminar Clamps in four neurosurgical centers in the United Kingdom was performed. Satisfactory bone fusion without complication occurred in all patients in whom lower cervical spinal stabilization (C3-C7) was performed. Complications occurred in 14 of 45 patients undergoing atlantoaxial arthrodesis. In 10 patients, one of the screws loosened, and in 4 patients, one of the clamps disengaged; additional operations to achieve bone fusion were required in 9 patients (20%). The Halifax Interlaminar Clamp is safe and effective for posterior stabilization in the lower cervical spine; there is a significant failure rate associated with its use for atlantoaxial arthrodesis.

Management of poor grade patients after subarachnoid haemorrhage: the importance of neuroradiological findings on clinical outcome

The prognosis for patients in poor neurological grade (WFNS grades IV and V) after subarachnoid haemorrhage (SAH) is grave. Previous reports of such patients have analysed outcome without defining either the cause or the course of the depressed level of consciousness. We report a retrospective study of the outcome of 62 consecutive patients in poor grade after SAH analysed with respect to their clinical course and the predominant computed tomographic feature. Neuroradiological findings were (1) intracranial haematoma, (2) hydrocephalus with or without intraventricular haemorrhage (IVH) and (3) SAH alone. Sixteen patients (25.8%) had a Glasgow Coma Score (GCS) < or = 12 on admission to hospital and subsequently deteriorated. The predominant computed tomographic feature of these patients was hydrocephalus/IVH. Twelve patients (19.4%) had a GCS < or = 12 on admission and subsequently improved without intervention; all had SAH on computed tomography (CT) on admission. Thirty-four patients (54.8%) had a GCS < or = 12 on admission and did not improve or improved only after emergency surgical intervention. Haematoma (44%) and hydrocephalus/IVH (47%) were the predominant CT features in this group. The overall mortality in the 62 patients was 44%. Fifty-two per cent of patients achieved a good outcome or were moderately disabled. Patients harbouring an intracerebral haematoma had a significantly poorer prognosis when compared with the other groups. Patients in poor neurological grade after SAH are a heterogenous group both clinically and neuroradiologically. Management approaches must consider the cause of clinical deterioration and the related CT findings.

Autoimmune Hypothyroidism Coexisting with a Pituitary Adenoma Secreting Thyroid-Stimulating Hormone, Prolactin and α-Subunit

A 44-year-old woman presented to her GP with excessive tiredness. She had positive thyroid microsomal and thyroglobulin autoantibodies and was found to have an elevated serum thyroid-stimulating hormone (TSH) concentration of 8.37 (normal = 0·15–3·5) mU/L and a low normal total thyroxine (T4) of 86 (reference range 60–145) nmol/L. She was rendered symptom free on a dose of 150μg of thyroxine per day. However, her TSH failed to return to normal, and following a further increase in her thyroxine dose she was referred to the endocrine clinic for further assessment. Her TSH at this stage was 14mU/L, free T4 (fT4) 28 (normal = 10–27) pmol/L and free T3 (fT3) 10 (normal = 4·3–7·6) pmol/L. She denied any problems with adherence to her medication. Her serum prolactin was elevated at 861 (normal = 60–390) mU/L. A pituitary tumour was suspected and an MRI scan showed a macroadenoma of the right lobe of the pituitary, extending into the suprasellar cistern. The tumour was resected trans-sphenoidally. Electron microscopy showed a dual population of neoplastic cells compatible with a thyrotroph cell and prolactin-secreting adenoma. Immunocytochemistry and cell culture studies confirmed the secretion of TSH, prolactin and α-subunit. Postoperative combined anterior pituitary function tests did not demonstrate any deficiency of anterior pituitary hormones. A repeat MRI scan showed no significant residual tumour; however, her serum TSH and prolactin levels remained high and she was given a course of pituitary irradiation. This case illustrates the difficulty of diagnosing a TSHoma when it coexists with autoimmune hypothyroidism. We believe the combination of pathologies reported here is unique.

A national survey of thromboprophylaxis in traumatic brain injury in the United Kingdom.

Abstract Introduction: Patients with traumatic brain injury (TBI) are at increased risk of venous thromboembolic events (VTE). In this survey, we aimed to assess current practice in the United Kingdom and identify areas of variation for further investigation. Methods: We distributed a case-based survey to neurosurgical consultants and trainees via e-mail. The survey included four index TBI cases commonly seen: a surgically treated acute extradural haematoma, bilateral frontal contusions treated conservatively, diffuse axonal injury requiring critical care and a conservatively managed small acute subdural haematoma. Each case vignette included questions looking at a range of areas regarding thromboprophylaxis. Results: Sixty-two responses were collected among UK neurosurgeons with a good geographic distribution. In each case, over 90% of respondents would initiate mechanical prophylaxis (MTP) at admission. There was greater variation on the decision to commence pharmacological prophylaxis (PTP). Consultants showed a higher willing to commence PTP across all cases (84%) compared to trainees (77.4%). Low molecular weight heparin (LMWH) was the favoured PTP agent in over 90% of respondents. There was significant variability in the timing of initiation of PTP within and between cases. The median times to commence PTP across all four cases ranged from 1 to 7 days. Conclusion: This survey highlighted broad consensus on the use of MTP and choice of PTP agent, when used. However, the survey also demonstrated wide intra-case variation on whether to start PTP and particularly the timing of initiation. This discordance in practice shines light on the lack of evidence guiding thromboprophyalxis in TBI and adds weight to the need for prospective randomised trials to guide clinical management.

THE CLINICAL FEATURES AND PROGNOSIS OF SCAN NEGATIVE URO-NEUROLOGICAL DISORDERS

Background Studies from our group have shown that around half of patients presenting with cauda equina syndrome (CES) have normal imaging, many of whom may have evidence of a functional neurological disorder. We have also shown high rates of comorbidity of functional neurological disorders in patients with idiopathic chronic urinary retention (including Fowlers syndrome). Aims To determine what proportion of patients with ‘scan negative’ CES and chronic dysfunctional voiding have a functional disorder by clinical consensus. To determine distress, disability and ongoing symptoms in patients with ‘scan positive’ and ‘scan negative’ CES three months after symptom onset. To determine frequency of comorbid functional disorders, distress, disability and physical function in patients with voiding dysfunction and a control urological group. Project Plans: The Back or Leg Pain with Bladder symptoms study (BLB) study is a prospective case control study of all patients admitted with possible CES to the Western General Hospital, Edinburgh. The Overview of Comorbidity in Chronic Urinary Retention (OCCUR) study is a prospective cohort study and retrospective notes review of patients with Chronic Urinary Retention (including Fowlers syndrome) via the urodynamic clinics in Glasgow, Edinburgh and London.