Professional background

Consultant neurosurgeon & clinical senior lecturer 1999 onwards

Senior registrar at Newcastle-upon-Tyne 1995 to 1999

MRC research fellowship at Institute of Neurology 1992-1995

Registrar at Atkinson Morley's/Queen Square/Great Ormond Street 1989-1992

Westminster rotation for general/orthopaedic training 1987-1989

Demonstrator in anatomy and junior posts in Cambridge 1984-1986

Surgical Practice
Consultant neurosurgeon at the National Hospital for Neurology and Neurosurgery performing general neurosurgery, with sub-speciality interests in hydrocephalus, neurovascular surgery, intracranial pressure, chronic headache and neuro-endoscopy. Clinical lead for hydrocephalus and member of the multidisciplinary Neurovascular Group.

Chairman of the Surgical Training Committee for Neurosurgery. Programme Director for the North London Neurosurgical Training Rotation (the largest neurosurgical training programme in the U.K.).

Regular lectures to undergraduates as part of their neurosciences attachment. Frequent lectures to nurses and therapists, and outreach teaching sessions at our core referring hospitals. Regular lecturer on MSc course and MSc/PhD project supervisor at the Institute of Neurology.

Regional specialty professional advisor for the Royal College of Surgeons.

Member of the Professional Affairs Board of the Royal College of Surgeons.

Other Activities
Working group of the International Headache Society which developed the IHS diagnostic criteria (Non-vascular intracranial causes of headache). Chairman, H-C Diener.

Research interests

  • Clinical and translational research in hydrocephalus
  • Intracranial pressure
  • Cerebral blood flow and cerebral vascular abnormalities
  • Neuromodulation for chronic intractable headache


Book Chapters
Miller S, Watkins L, Matharu MS. Trigeminal autonomic cephalalgias I: peripheral neuromodulation (occipital nerve and sphenopalatine ganglion stimulation). In: Surgery of the Autonomic Nervous System (Hyam JA, Pereira EAC, Green AL. Eds). Oxford University Press 2016. DOI:10.1093/med/9780199686407.003.0011

Watkins L, Thomas DGT. Traumatic injuries to the head. In: Oxford Textbook of Medicine 5th Edition (Warrell DA, Cox TM, Firth JD. Eds). Oxford University Press 2010. 24.10.3: 4963-4967

Elwell V, Watkins L. Consent in Neurosurgery. In: Consent in Surgery – a practical guide (Khundar R, De Silva S, Chowdhury R. Eds). Radcliffe Publishing 2010. 5: 49-62

Watkins L, Thomas DGT. Neurosurgery: Current trends and recent innovations. In: Key Topics in Surgical Research and Methodology. Springer-Verlag Berlin Heidelberg 2010. doi: 10.1007/978-3-540-71915-1_72

Watkins LD. Raised intracranial pressure. In: Clinical Neurology. (Scadding JW, Fowler, T. Eds). Hodder 2003. 18: 362-382

Journal Articles


D'Antona L, McHugh JA, Ricciardi F, Thorne LW, Matharu MS, Watkins LD, Toma AK, Bremner FD. Association of Intracranial Pressure and Spontaneous Retinal Venous Pulsation. JAMA Neurol. 2019 Sep 9. doi: 10.1001/jamaneurol.2019.2935

Fernández-Méndez R, et al (UK Shunt Registry Collaborators). Current epidemiology of cerebrospinal fluid shunt surgery in the UK and Ireland (2004–2013). J Neurol Neurosurg Psychiatry 2019 Jul;90(7):747-754. doi: 10.1136/jnnp-2018-319927

Craven CL, Ramkumar R, D'Antona L, Thompson SD, Thorne L, Watkins LD, Toma AK. Natural history of ventriculomegaly in adults: a cluster analysis. J Neurosurg. 2019 Feb 8:1-8. doi: 10.3171/2018.8.JNS18119

Craven CL, Thompson SD, Toma AK, Watkins LD. Superficial and Deep Skin Preparation with Povidone-Iodine for Ventriculoperitoneal Shunt Surgery : A Technical Note. Korean Neurosurg Soc. 2019 Jan;62(1):123-129. doi: 10.3340/jkns.2017.0282

Craven CL, Chapman MD, D'Antona L, Thompson SD, Lakdawala N, Zetterberg H, Watkins LD, Toma AK. Lumbar drains can affect CSF biomarker levels. J Clin Pathol. 2019 Jan;72(1):91-92. doi: 10.1136/jclinpath-2018-205296

Donald R, et al. (BrainIT Group Collaborators). Forewarning of hypotensive events using a Bayesian artificial neural network in neurocritical care. J Clin Monit Comput. 2019 Feb;33(1):39-51. doi: 10.1007/s10877-018-0139-y


Funnell JP, Craven CL, D'Antona L, Thompson SD, Chari A, Thorne L, Watkins LD, Toma AK. Intracranial pressure in patients with papilloedema. Acta Neurol Scand. 2018 Aug;138(2):137-142. doi: 10.1111/ane.12922

Funnell JP, Craven CL, Thompson SD, D'Antona L, Chari A, Thorne L, Watkins LD, Toma AK. Pulsatile versus non-pulsatile tinnitus in idiopathic intracranial hypertension. Acta Neurochir (Wien). 2018 Oct;160(10):2025-2029. doi: 10.1007/s00701-018-3587-8.

Kolias AG, et al. (Dex-CSDH Trial Collaborators). Dexamethasone for adult patients with a symptomatic chronic subdural haematoma (Dex-CSDH) trial: study protocol for a randomised controlled trial. Trials. 2018 Dec 4;19(1):670. doi: 10.1186/s13063-018-3050-4.

Dasgupta D, D'Antona L, Aimone Cat D, Toma AK, Curtis C, Watkins LD, Thorne L. Simulation workshops as an adjunct to perioperative care bundles in the management of external ventricular drains: improving surgical technique and reducing infection. J Neurosurg. 2018 Oct 1:1-5. doi: 10.3171/2018.5.JNS172881

Craven CL, Baudracco I, Thompson SD, Thorne L, Watkins LD, Toma AK. Transtentorial Distortion Syndrome: Consistent Complication Following Lateral and Fourth Ventricular Shunting in Adults. World Neurosurg. 2018 Feb;110:e514-e519. doi: 10.1016/j.wneu.2017.11.032

Jamjoom AAB, et al. (British Neurosurgical Trainee Research Collaborative). Prospective, multicentre study of external ventricular drainage-related infections in the UK and Ireland. J Neurol Neurosurg Psychiatry. 2018 Feb;89(2):120-126

Asif H, Craven CL, Siddiqui AH, Shah SN, Matloob SA, Thorne L, Robertson F, Watkins LD, Toma AK. Idiopathic intracranial hypertension: 120-day clinical, radiological, and manometric outcomes after stent insertion into the dural venous sinus. J Neurosurg. 2018 Sep;129(3):723-731. doi: 10.3171/2017.4.JNS162871

Miller S, Lagrata S, Watkins L, Matharu M. Occipital Nerve Stimulation for Medically Refractory Chronic Paroxysmal Hemicrania. Headache. 2017 Nov;57(10):1610-1613. doi: 10.1111/head.13187

Miller S, Watkins L, Matharu M. Predictors of response to occipital nerve stimulation in refractory chronic headache. Cephalalgia. 2018 Jun;38(7):1267-1275. doi: 10.1177/0333102417728747

Miller S, Watkins L, Matharu M. Long-term follow up of intractable chronic short lasting unilateral neuralgiform headache disorders treated with occipital nerve stimulation. Cephalalgia. 2018 Apr;38(5):933-942. doi: 10.1177/0333102417721716

Craven CL, Baudracco I, Zetterberg H, Lunn MPT, Chapman MD, Lakdawala N, Watkins LD, Toma AK. The predictive value of T-tau and AB1-42 levels in idiopathic normal pressure hydrocephalus. Acta Neurochir (Wien). 2017 Dec;159(12):2293-2300. doi: 10.1007/s00701-017-3314-x

Chari A, Dasgupta D, Smedley A, Craven C, Dyson E, Matloob S, Thompson S, Thorne L, Toma AK, Watkins L. Intraparenchymal intracranial pressure monitoring for hydrocephalus and cerebrospinal fluid disorders. Acta Neurochir (Wien). 2017 Oct;159(10):1967-1978. doi: 10.1007/s00701-017-3281-2

Matloob SA, Toma AK, Thompson SD, Gan CL, Robertson F, Thorne L, Watkins LD. Effect of venous stenting on intracranial pressure in idiopathic intracranial hypertension. Acta Neurochirurgica 2017 Aug;159(8):1429-1437. doi: 10.1007/s00701-017-3229-6

Thompson SD, Shand Smith JD, Khan AA, Luoma AMV, Toma AK, Watkins LD. Shunting of the over 80s in normal pressure hydrocephalus. Acta Neurochir (Wien). 2017 Jun;159(6):987-994. doi: 10.1007/s00701-017-3171-7

Miller S, Watkins L, Matharu MS. Treatment of intractable hemicrania continua by occipital nerve stimulation. J Neurol Neurosurg Psychiatry. 2017 Sep;88(9):805-806. doi: 10.1136/jnnp-2017-315747

Miller S, Matharu M, Watkins L. Treatment of intractable chronic cluster headache by occipital nerve stimulation: a cohort of 51 patients. European Journal of Neurology, 2017; 24: 381–390

Thompson S, Craven C, Toma A, Thorne L, Watkins L, Coutts A. Elective ICP monitoring: how long is long enough? Acta Neurochirurgica, 2017; 159: 485-490

Hermes J, Lakshmanan R, Watkins L, Davagnanam I. Teaching NeuroImages: Intracranial arterial dissection. Neurology, 88:e111-e112

Miller S, Watkins LD, Matharu MS. Long-term outcomes of occipital nerve stimulation for chronic migraine: a cohort of 53 patients. The Journal of Headache and Pain, 2016. 17:68. DOI: 10.1186/s10194-016-0659-0

Craven C, Toma AK, Watkins LD. Persistent hydrocephalus due to postural activation of a ventricular
shunt anti-gravity device. Journal of Clinical Neuroscience, 2016. DOI: 10.1016/j.jocn.2016.11.004

Craven C, Toma AK, Mostafa T, Patel N, Watkins LD. The predictive value of DESH for shunt responsiveness in idiopathic normal pressure hydrocephalus. Journal of Clinical Neuroscience, 2016. DOI:10.1016/j.jocn.2016.09.004

Hutchinson PJ, et al. (RESCUEicp Trial Collaborators). Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension. N Engl J Med. 2016 Sep 22;375(12):1119-30. doi: 10.1056/NEJMoa1605215

Craven C, Asif H, Farrukh A, Somavilla F, Toma AK, Watkins LD. Case series of ventriculopleural shunts in adults: a single-center experience. Journal of Neurosurgery, 2016. DOI:10.3171/2016.4.JNS16641

Craven C, Toma AK, Khan AA, Watkins LD. The role of ICP monitoring in patients with persistent cerebrospinal fluid leak following spinal surgery: a case series. Acta Neurochirurgica, 2016. DOI:10.1007/s00701-016-2882-5

Toma AK, Watkins LD. Surgical management of idiopathic normal pressure hydrocephalus: a trial of a trial. British Journal of Neurosurgery, 2016. DOI:10.1080/02688697.2016.1229751

Miller S, Fox Z, Watkins LD, Matharu MS. Occipital nerve stimulation in highly refractory chronic headaches: identification of possible predictors of success. Journal of Neurology Neurosurgery & Psychiatry, 2015; 86(11):e4.175-e4. DOI:10.1136/jnnp-2015-312379.81

McAllister JP 2nd, et al. (Hydrocephalus Symposium Expert Panel). An update on research priorities in hydrocephalus: overview of the third National Institutes of Health-sponsored symposium "Opportunities for Hydrocephalus Research: Pathways to Better Outcomes". J Neurosurg. 2015 Dec;123(6):1427-38. doi: 10.3171/2014.12.JNS132352

Malem DN, Shand Smith JD, Toma AK, Sethi H, Kitchen ND, Watkins LD. An investigation into the clinical impacts of lowering shunt opening pressure in idiopathic normal pressure hydrocephalus: A case series. British Journal of Neurosurgery 2015; 29(1): 18–22. DOI:10.3109/02688697.2014.950630

Matloob SA, Toma AK, Thorne L, Watkins LD. Surgically managed idiopathic intracranial hypertension in adults: a single centre experience. Acta Neurochirurgica 2015; 157(12): 2099-2103

deSouza R-M, Toma AK, Watkins LD. Medication overuse headache – An under-diagnosed problem in shunted idiopathic intracranial hypertension patients. British Journal of Neurosurgery 2015; 29(1): 30-34, DOI: 10.3109/02688697.2014.950633

Wilson D, Marshall CR, Solbach T, Watkins LD, Werring DJ. Intraventricular hemorrhage in reversible cerebral vasoconstriction syndrome. Journal of Neurology, 2014; 261(11). DOI:10.1007/s00415-014-7499-0

Adams A, Shand Smith JD, Watkins LD, McEvoy AW, Elneil S, Zrinzo L, Davagnanam I. Neural stimulators: A guide to imaging and postoperative appearances. Clinical Radiology, 2014; 69(10):993-1003

Sciacca S, Shand Smith JD, Akram H, Asim A, Matharu MS, Watkins LD. Rechargeable occipital nerve stimulator systems: A patient satisfaction study. British Journal of Neurosurgery, 2014; 28(5). DOI: 10.3109/02688697.2014.889657

Lambru G, Shanahan P, Watkins LD, Matharu MS. Occipital nerve stimulation in the treatment of medically intractable SUNCT and SUNA. Pain Physician, 2014; 17(1):29-41

Toma AK, Papadopoulos MC, Stapleton S, Kitchen ND, Watkins LD. Systematic review of the outcome of shunt surgery in idiopathic normal-pressure hydrocephalus. Acta Neurochirurgica 08/2013; DOI:10.1007/s00701-013-1835-5

Toma AK, Robertson F, Wong K, Joshi Y, Haridas A, Grieve J, Watkins LD, Kitchen ND, Brew S. Early single centre experience of flow diverting stents for the treatment of cerebral aneurysms. British Journal of Neurosurgery 05/2013; DOI:10.3109/02688697.2013.793292

Kirkman MA, Watkins LD, Kitchen ND, Sethi H. Early years neurosurgical training in the era of the European Working Time Directive. British Journal of Neurosurgery 05/2013; DOI:10.3109/02688697.2013.793290

Khan AA, Shand Smith JD, Kirkman MA, Robertson FJ, Wong K, Dott C, Grieve JP, Watkins LD, Kitchen ND. Angiogram negative subarachnoid haemorrhage: Outcomes and the role of repeat angiography. Clin Neurol Neurosurg 2013; 115: 1470-1475

Rasul FT, Marcus HJ, Toma AK, Thorne L, Watkins LD. Is endoscopic third ventriculostomy superior to shunts in patients with non-communicating hydrocephalus? A systematic review and meta-analysis of the evidence. Acta Neurochir (2013) 155:883–889

Nataraj A, Mohamed MB, Gholkar A, Vivar R, Watkins L, Aspoas R, Gregson B, Mitchell P, Mendelow AD. Multimodality Treatment of Cerebral Arteriovenous Malformations. World Neurosurg 2013 doi: 10.1016/j.wneu.2013.02.064

Magdalinou NK, Ling H, Shand Smith JD, Schott JM, Watkins LD. Normal pressure hydrocephalus or progressive supranuclear palsy? A clinicopathological case series. J Neurol 2013 Apr;260(4):1009-13

Toma AK, Papadopoulos MC, Stapleton S, Kitchen ND, Watkins LD. Conservative versus surgical management of idiopathic normal pressure hydrocephalus: a prospective double-blind randomized controlled trial: study protocol. Acta Neurochir Supplement 2012 Jan;113:21-3

Rasul FT, Toma AK, Khan AA, Plant GT, Watkins LD. Pseudotumor cerebri presenting with visual failure in promyelocytic leukemia. Journal of Medical Case Reports, 2012; 6:408

Tarnaris A, Haliasos N, Watkins LD. Endovascular treatment of ruptured intracranial aneurysms during pregnancy: Is this the best way forward? Case report and review of the literature. Clin Neurol Neurosurg. 2012 Jul;114(6):703-6

Shand Smith JD, Toma AK, Watkins LD, Kitchen ND. Secondary normal pressure hydrocephalus in a patient with isolated frontal dilatation – an insight into pathophysiology? Acta Neurochir (Wien), 2011; 154(4):769-72; discussion 772

Tarnaris A, Toma AK, Pullen E, Chapman MD, Petzold A, Cipolotti L, Kitchen ND, Keir G, Lemieux L, Watkins LD. Cognitive, biochemical and imaging profile of patients suffering from idiopathic normal pressure hydrocephalus. Alzheimers Dement. 2011 Sep;7(5):501-8

Toma AK, Stapleton S, Papadopoulos MC, Kitchen ND, Watkins LD. Natural history of idiopathic normal-pressure hydrocephalus. Neurosurg Rev. 2011 Oct;34(4):433-9

Chinthapalli VK, Watkins LD. Ventriculoperitoneal Shunt Tap. eMedicine from WebMD. Updated August 12, 2011. Available at:

Tarnaris A, Toma AK, Chapman MD, Keir G, Kitchen ND, Watkins LD. Use of cerebrospinal fluid amyloid-? and total tau protein to predict favorable surgical outcomes in patients with idiopathic normal pressure hydrocephalus. . J Neurosurg. 2011 Jul;115(1):145-50

Tarnaris A, Toma AK, Watkins LD, Kitchen ND. Is there a difference in outcomes of patients with idiopathic intracranial hypertension with the choice of cerebrospinal fluid diversion site: A single centre experience. Clin Neurol Neurosurg. 2011 Jul;113(6):477-9

Toma AK, Tarnaris A, Kitchen ND, Watkins LD. Use of proGAV® shunt valve in normal pressure hydrocephalus. Neurosurgery 2011 Feb 26. [Epub ahead of print]

Toma AK, Holl E, Kitchen ND, Watkins LD. Evans' index revisited: the need for an alternative in normal pressure hydrocephalus. Neurosurgery 2011 Apr;68(4):939-44

Tarnaris A, Toma AK, Chapman MD, Petzold A, Keir G, Kitchen ND, Watkins LD. Rostrocaudal dynamics of CSF biomarkers. Neurochem Res. 2011 Mar;36(3):528-32

Saper JR et al [See Collaborators]. Occipital nerve stimulation for the treatment of intractable chronic migraine headache: ONSTIM feasibility study. Cephalalgia. 2011 Feb;31(3):271-85

Toma AK, Tarnaris A, Kitchen ND, Watkins LD. Working towards patient oriented outcome assessment in normal pressure hydrocephalus, what is the most important? Acta Neurochir (Wien). 2011 Jan;153(1):177-80

Toma AK, Dherijha M, Kitchen ND, Watkins LD. Use of lumboperitoneal shunts with the Strata NSC valve: a single-center experience. J Neurosurg. 2010 Dec;113(6):1304-8

Toma AK, Tarnaris A, Kitchen ND, Watkins LD. Investigating shunt function using continuous intracranial pressure monitoring in adults: single center experience. J Neurosurg. 2010 Dec;113(6):1326-30

Matharu M, Watkins L, Shanahan P. POH04 Treatment of medically intractable SUNCT and SUNA with occipital nerve stimulation. Journal of neurology, neurosurgery, and psychiatry 2010; 81(11):e51-2

Toma AK, Tarnaris A, Kitchen ND, Watkins LD. Continuous intracranial pressure monitoring in pseudotumour cerebri: Single centre experience. Br J Neurosurg. 2010 Oct;24(5):584-8

Toma AK, Tarnaris A, Kitchen ND, Watkins LD. Ventriculosinus shunt. Neurosurg Rev. 2010 Apr;33(2):147-52; discussion 153

Tailor J, Goetz P, Chandrashekar H, Stephen T, Schiariti M, Grieve J, Watkins L, Brew S, Robertson F, Kitchen N. Stability of ruptured intracranial aneurysms treated with detachable coils: is delayed follow-up angiography warranted? Br J Neurosurg. 2010 Aug;24(4):405-9

Tarnaris A, Toma AK, Kitchen ND, Watkins LD. Ongoing search for diagnostic biomarkers in idiopathic normal pressure hydrocephalus. Biomarkers in Medicine 2009 Dec; 3 (6):787-805

Tarnaris A, Toma AK, Chapman MD, Petzold A, Kitchen ND, Keir G, Watkins LD. The longitudinal profile of CSF markers during external lumbar drainage. J Neurol Neurosurg Psychiatry. 2009 Oct;80(10):1130-3

Toma AK, Tarnaris A, Grieve JP, Watkins LD, Kitchen ND. Adjustable shunt valve-induced magnetic resonance imaging artifact: a comparative study. J Neurosurg. 2010 Jul;113(1):74-8

Toma AK, Camp S, Watkins LD, et al. External ventricular drain insertion accuracy: is there a need for change in practice? Neurosurgery 2009; 65:1197-1201

Burns B, Watkins L, Goadsby PJ. Treatment of intractable chronic cluster headache by occipital nerve stimulation in 14 patients. Neurology 2009 Jan 27;72(4):341-5

Tarnaris A, Kitchen ND, Watkins LD. Noninvasive biomarkers in normal pressure hydrocephalus: evidence for the role of neuroimaging. Journal of Neurosurgery 2009 May; 110(5):837-51

2008 and earlier
Burns B, Watkins L, Goadsby PJ. Treatment of hemicrania continua by occipital nerve stimulation with a bion device: long-term follow-up of a crossover study. Lancet Neurol. 2008 Nov;7(11):1001-12

Burns B, Watkins L, Goadsby PJ. Treatment of medically intractable cluster headache by occipital nerve stimulation: long-term follow-up of 13 patients. Cephalalgia 2007; 27:1190

Burns B, Watkins L, Goadsby PJ. Successful treatment of medically intractable cluster headache by occipital nerve stimulation. Lancet 2007; 369(9567):1099-106.

Frazer D, Ahuja A, Watkins L, Cipolotti L. Coiling versus clipping for the treatment of aneurysmal subarachnoid haemorrhage: a longitudinal investigation into cognitive outcome. Neurosurgery 2007;60(3):434-41; discussion 441-2

Tarnaris, A; Watkins, LD; Kitchen, ND. Biomarkers in chronic adult hydrocephalus. Cerebrospinal Fluid Research 2006, 3:11

Perel P, et al. (MRC CRASH Trial Collaborators). Predicting outcome after traumatic brain injury: practical prognostic models based on large cohort of international patients. BMJ 2008 Feb 23;336(7641):425-9. doi: 10.1136/bmj.39461.643438.25

Zrinzo,LU; Crocker, M; Zrinzo, LV; Thomas, DGT; Watkins, LD. Commercial flight and patients with intracranial mass lesions: a caveat. J Neurosurg 2006; 105:627–630.

Caesar B, Middleton PM, Watkins LD. Sudden onset of vomiting as a presentation of perimesencephalic subarachnoid haemorrhage. Eur J Emerg Med. 2005 Aug;12(4):185-7

Demetriades AK, Cox TC, Watkins LD. Hyperacute head injuries and the timing of computed tomography. J Trauma. 2004 Oct;57(4):925

Gnanalingham, KK; Watkins, L; Goadsby, PJ. 14 mmHg: a case of raised intracranial pressure?
British Journal of Neurosurgery 2004; 18(3):303-306.

Casimiro, MV; McEvoy, AW; Watkins, LD, et al. A comparison of risk factors in the etiology of mirror and nonmirror multiple intracranial aneurysms. Surgical Neurology 2004; 61(6):541-545.

Ibrahim A, Ashkan K, Smith M, Watkins L. Anticoagulation in a head injured patient. Journal of the Royal Society of Medicine 2003; 96(12):591-2.

Atkin G, Watkins L, Rich P. Bilateral sensorineural hearing loss complicating basal skull fracture. Br J Neurosurg. 2002 Dec;16(6):597-600.

Gnanalingham K, Taylor W, Watkins L. Dual technique for obliteration of small arteriovenous malformations. Br J Neurosurg. 2002 Aug;16(4):376-80.

Watkins LD. Nitric oxide and cerebral blood flow: an update. Cerebrovasc Brain Metab Rev. 1995 Winter;7(4):324-337

Watkins LD, Mendoza N, Cheesman AD, Symon L. Glomus jugulare tumours: a review of 61 cases. Acta Neurochir (Wien). 1994;130(1-4):66-70

Watkins LD, Hayward R, Andar U, Harkness W. The diagnosis of blocked cerebrospinal fluid shunts: a prospective study of referral to a paediatric neurosurgical unit. Childs Nerv Syst. 1994 Mar;10(2):87-90

Watkins L, Khudados ES, Kaleoglu M, Revesz T, Sacares P, Crockard HA. Skull base chordomas: a review of 38 patients. 1958-1988. Br J Neurosurg. 1993;7(3):241-8.

Watkins LD, Uttley D, Archer DJ, Wilkins P, Plowman N. Giant cell tumors of the sphenoid bone. Neurosurgery. 1992 Apr;30(4):576-581

Watkins LD, Bell BA, Marsh HT, Uttley D. A scale for neurosurgical audit. Br J Neurosurg. 1990;4(6):463-465