John Hankinson

Congenital spinal arachnoid cysts; report of two cases and review of the literature.

Thepurpose ofthepresent communication isto describe twopatients, onewithacongenital extradural andonewithacongenital intradural arachnoid cyst ofthespine andtoreview therelevant literature. Congenital spinal arachnoid cyst isaveryrarecause ofspinal cordcompression. Itisoneofthemost favourable spinal lesions forsurgical removal and recovery ofneurological function. Thetermcongenital isusedhereindistinction fromtheacquired variety. Acquired extradural arachnoid cysts may develop after operation whenasmall tearhasbeen madeinthespinal dura, after difficult lumbar puncture andafter spinal injury. Swansonand Fincher in1947reported fourcasesofacquired extradural arachnoid cysts after 1,700 exploratory laminectomies-an incidence of0068%.Three cases wereinthelumbar region andhadfollowed adural tearduring disc removal. Thefourth cyst wasrelated toa non-penetrating injury tothelumbarspine. Acquired intradural arachnoid cysts arealsoassociated withspinal adhesive arachnoiditis, although cystformation isnotconstantly present inthis condition. Thecongenital intradural cysts area separate entity andhavebeendescribed intheliterature under avariety ofnames-for example, spinal arachnoid diverticulae, leptomeningeal cysts, localized adhesive spinal arachnoiditis, andarachnitis adhaesa circumscripta. Theappearances ofadhesive arachnoiditis areabsent on myelography insuchcasesand, although usually single, thecysts maybemultiple. CASE 1

Extradural haemorrhage—a hazard of ventricular drainage

Three cases of extradural haematoma during ventricular drainage are reported and the relevant literature has been reviewed. Aetiology, diagnosis, and management are discussed. Defective blood clotting is mentioned as a possible precipitating factor.

An Introduction to Neurosurgery

An Introduction to Neurosurgery Third Edition By Bryan Jennett. (Pp. 366; illustrated; £9.95.) Heinemann Medical Books: London. 1977. This is the third edition of an excellent small textbook which covers a wide range of neurosurgical topics and would be ideal for medical students, the newly qualified, and neurosurgical trainees at the start of their careers. Although the text is concise it is, as one would expect, an easy book to read. An important feature is the addition to each chapter of a short bibliography and this would apply particularly to neurosurgical trainees. The approach to the subject is a very practical one, describing what could be expected from the history and clinical findings and what is then available by special investigation. As is proper in an introduction to the subject, more controversial topics are not dealt with. The chapters on the pathology, natural history, and the management of the head-injured patient will prove of special value to the newly qualified doctor who is not working in a neurosurgical department and yet is often called upon to deal with such cases in casualty departments. This book can be strongly recommended and fulfils its purpose admirably.

CEREBRAL ANGIOMAS: ADVANCES IN DIAGNOSIS AND THERAPY

gical features are discussed together with some of the radiological findings, the clinical correlates, EEG and neuroradiological investigations (but no EMI scan), diagnostic criteria and prognosis. Very little is mentioned about therapeutic approaches or long term sequelae of surgery. The review of the literature though fairly extensive has a number of obvious omissions but covers 10 fully printed pages. The personal contribution consists of only 16 cases between 29 and 75 years of age, and some of them were operated upon. The illustrations, both of the histological findings and of some of the arteriograms, are satisfactory. The index is limited to a list of the chapters and their subdivisions. It is difficult to assess for whom this book was written, as the discussion of the literature is primarily aimed at the interested medical student rather than at the specialist. However, on the whole, the information is fairly well digested and does not give the impression of consulting just a telephone directory. G. PAMPIGLIONE