J Neurol Neurosurg Psychiatry 1999;66:703–721 703 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.703 on 1 June 1999. Downloaded from REVIEW: NEUROLOGY AND MEDICINE Neurology of the pituitary gland J R Anderson, N Antoun, N Burnet, K Chatterjee, O Edwards, J D Pickard, N Sarkies This review will focus on those aspects of Pituitary disease often presents insidiously pituitary disease immediately relevant to neu- and in retrospect might have been detected rologists and neurosurgeons when assessing earlier. The symptoms of hormonal hyperse- and counselling patients. It is essential to adopt cretion in endocrinologically active tumours a multidisciplinary approach to the diagnosis will obviously present before evidence of and management of pituitary disease as suprasellar or parasellar extension. Although emphasised by the recently published guide- somatic changes usually bring the growth hor- lines from the Royal College of Physicians of mone secreting adenoma to medical attention 1–4 London. first, the neurologist may encounter nerve entrapment (particularly the carpal tunnel syn- Range of pathology presenting in the drome), proximal myopathy (weakness dispro- sellar region portionate to the increased body mass), The commonest lesions presenting in this peripheral neuropathy (muscle atrophy, distal region are pituitary tumours (incidence of sensory loss, and neuropathic joints) and the Department of 15–20/million/year), including adenomas and psychological and emotional sequelae of the Neuropathology, craniopharyngiomas, aneurysms, and meningi- disease.9 It has been debated whether the emo- Box 235 omas, but many other diseases need to be con- tional sequelae reflect a specific interaction J R Anderson sidered (table 1). between growth hormone and the limbic 10 Department of system. The headaches are often bitemporal, Neuroradiology, Neurological presentations of pituitary periorbital, or referred to the vertex, and do not Box 219 seem to correlate with the size of the mass.11 N Antoun disease ”Pituitary incidentalomas” may be disclosed Fronto-occipital headaches have also been described that may be exacerbated by cough- Department of when investigating unrelated disease (fig 1). Neuro-oncology, Although figures from 5% to 27% have been ing. More remotely, acromegaly may present Box 193 quoted for the incidence of subclinical adeno- with the neurological complications of diabetes N Burnet mellitus and hypertension. Some patients may mas at postmortem, far fewer are of significant http://jnnp.bmj.com/ size—that is, over 5 mm in diameter with present with symptoms drawn from more than Department of one endocrinopathy when there is dual secre- Diabetes and deviation of the stalk and unilateral enlarge- Endocrinology Box 157 ment of the gland. Careful endocrine and tion by the pituitary adenoma—for example, of K Chatterjee visual assessments are required and, where no growth hormone and prolactin. Finally, not all abnormalities are found, most can be managed growth hormone hypersecretion is the product Department of conservatively with follow up MRI.5–8 of a pituitary adenoma—a rapidly progressive Diabetes and Endocrinology, Box 49 DiVerential diagnosis of neoplasms and “tumour-like” lesions of the sellar region2 O Edwards on September 28, 2021 by guest. Protected copyright. Tumours of adenohypophyseal origin Cysts, hamartomas, and malformations Department of Pituitary adenoma Rathke’s cleft cyst Neurosurgery, Box 167 Pituitary carcinoma Arachnoid cyst J D Pickard Tumours of neurohypophyseal origin Epidermoid cyst Granular cell tumour Dermoid cyst Department of Astrocytoma of posterior lobe and/or stalk (rare) Gangliocytoma Ophthalmology, Box Tumours of non-pituitary origin Empty sella syndrome Craniopharyngioma Metastatic tumours 41, Addenbrooke’s Germ cell tumours Carcinoma Hospital, Cambridge, Glioma (hypothalamic, optic nerve/chiasm, infundibulum) Plasmacytoma UK Meningioma Lymphoma N Sarkies Haemangiopericytoma Leukaemia Chordoma Inflammatory conditions Correspondence to: Haemangioblastoma Infection/abscess Professor JD Pickard, Lipoma Mucocoele Department of Giant cell tumour of bone Lymphocytic hypophysitis Neurosurgery, Box 167, Chondroma Sarcoidosis Fibrous dysplasia Langerhans’ cell histiocytosis Addenbrooke’s Hospital, Sarcoma (chrondrosarcoma, osteosarcoma, fibrosarcoma) Giant cell granuloma Cambridge CB2 2QQ, UK. Postirradiation sarcomas Vascular lesions Telephone 0044 1223 Paraganglioma Internal carotid artery aneurysms 336946. Schwannoma Cavernous angioma Glomangioma Received 2 Novembr 1998 Esthaesioneuroblastoma and in revised form Primary lymphoma 27 January 1999 Melanoma Accepted 4 February 1999 704 Anderson, Antoun, Burnet, et al J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.703 on 1 June 1999. Downloaded from Figure 2 (A) Pituitary haemorrhage which presented with apoplexy. Coronal TI weighted image. High signal blood within an enlarged sella. Infundibulum deviated to the left. (B) Infarction of macroadenoma. Postgadolinium coronal TI weighted image. The optic chiasm is stretched and displaced superiorly (arrow head). Enhancement in residual viable adenoma superiorly and to the left. The very bright signal represents small areas of haemorrhage headache may be the presenting feature. Hypogonadism may be compounded by mild Figure 1 (A) Normal hyperprolactinaemia resulting from the eVect appearance of pituitary of raised intrasellar pressure on the normal gland. Sagittal TI weighted pituitary gland (see later). The neurological image. Note the bright signal from the posterior lobe of the manifestations of hypothyroidism include car- pituitary. More posteriorly pal tunnel syndrome, slowing of cerebration, the dorsum sella (arrow and, less commonly, myotonia and myopathy. http://jnnp.bmj.com/ head) is shown as linear high signal (marrow) surrounded The neurological consequences of hyperthy- by low signal (dense cortex). roidism including exophthalmos may herald a (B) Microadenoma on the thyrotrophinoma, the great majority of which left side. This has a lower are macroadenomas and hence may be accom- signal than normal pituitary. The normal pituitary and panied by headache, visual field defect, and cavernous sinus show galactorrhoea. However, other conditions may enhancement after be associated with hyperthyroidism plus a gadolinium injection. detectable concentration of serum thyro- on September 28, 2021 by guest. Protected copyright. history over a few months suggests an ectopic trophin and specialist expertise is required to tumour. diVerentiate them.13 The clinical manifestations of Cushing’s Children with pituitary and third ventricular syndrome are well known. The patient usually lesions may present with precocious puberty, presents at the microadenoma stage with growth retardation, diabetes insipidus, denial remarkably little if any abnormality on MRI. of visual failure, and the symptoms and signs of Symptoms can fluctuate, particularly in teen- either high or low pressure hydrocephalus. agers. Weakness from proximal myopathy, psy- chiatric disturbances including anxiety and Some diagnostic pitfalls panic attacks, the neurological consequences of Although most patients with a pituitary prob- obesity and hypertension, and benign intracra- lem fall within well defined categories, a nial hypertension12 may bring the patient to a minority present with manifestations of one of neurologist. the myriad of small print diagnoses. Ectopic A neurologist will usually see prolactinomas tumours may cause not only Cushing’s syn- and endocrinologically inactive tumours when drome but also acromegaly. Primary hypo- they have already reached a size suYcient to thyroidism may be accompanied by pituitary impinge on the normal pituitary and extrasellar gland swelling314 as the result of overstimula- structures (visual failure, ophthalmoplegia, tion from the hypothalamus leading to visual trigeminal sensory loss, and hydrocephalus). symptoms, hypopituitarism, headache, and less Hypogonadal symptoms, weakness, fatigue, or commonly, diabetes insipidus, syndrome of Neurology of the pituitary gland 705 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.703 on 1 June 1999. Downloaded from innappropriate antidiuretic hormone secretion an autoimmune attack on the adenohypophysis (SIADH), and precocious puberty. To add to and manifests histologically as diVuse lym- the confusion, one third of such female patients phocytic infiltration eVacing and destroying the may have menstrual irregularities as a reflec- normal glandular elements with progression to tion of modest hyperprolactinaemia leading to fibrotic scarring.19 The infiltrate is polyclonal, a misdiagnosis of prolactinoma. The pituitary predominantly T cell, but often includes swelling resolves with thyroxine and surgery is lymphoid germinal centres, plasma cells, and unnecessary. foamy macrophages. A similar lymphocytic The stalk compression syndrome refers to inflammatory process may be confined to the the symptoms and signs of hyperprolactinae- neurohypophyseal system, sparing the anterior mia in the presence of moderately raised prol- pituitary. By contrast, granulomatous hypo- actin concentrations and a sellar or suprasellar physitis is characterised by non-caseating mass but distortion of the pituitary stalk alone epithelioid granulomata and multinucleate does not correlate with prolactin Langhans-type giant cells. When restricted to concentrations.2315It is not clear why it is the the anterior pituitary this pathology probably prolactin