Malcolm Pell

Prediction and assessment of the severity of post-operative pain and of satisfaction with management.

&NA; A prospective observational study of cohorts of patients undergoing hip replacement (30), knee replacement (31), and spinal nerve root decompressive surgery (30) were interviewed pre‐operatively to identify factors which might correlate with and potentially predict severe post‐operative pain and dissatisfaction with analgesic management. The hip patients comprised 33% females and averaged 64 years, while the knee patients were 45% female and older (mean 71 years) and the spinal patients were 43% female and averaged 50 years. The three groups were similar with respect to all other pre‐operative variables. Pain intensity was assessed mainly by self‐report using the Present Pain Intensity (PPI) and Visual Analogue Scales (VAS) of the McGill Pain Questionnaire. The PPI was preferred by patients and nurses and, as there were no analytical advantages for the VAS, the PPI data are presented. The average post‐operative pain during routine management mainly with patient controlled intravenous opiate, was mild to moderate and declined over days 1–5, declined further at discharge but rose slightly 1 month after discharge. The hip replacement patients experienced significantly (P<0.01) less pain overall than the patients in the other two groups. Nurses’ assessments of pain severity from observed behaviour were low and agreed poorly with the patients’ self reports. Assessed on Likert Scales (0–6), the patients generally indicated good or excellent pain control, better than expected pain experience, and high levels of satisfaction with analgesic management. Significant (P≤0.01) multivariate correlates of severe post‐operative pain assessed by logistic regression analysis of 11 variables were female gender, high pre‐operative pain severity, and younger age. Significant (P≤0.01) multivariate correlates of both worse than expected pain experience and low satisfaction were female gender, high pre‐operative pain severity, high anxiety about risks and problems, low expected pain severity, age (younger) and high willingness to report pain. These variables may reasonably be tested in further studies as potential predictors of adverse post‐operative pain experience.

Postmortem analysis of bilateral subthalamic electrode implants in Parkinson's disease

This is the second neuropathological report detailing bilateral electrodes targeting the subthalamic nucleus (STN) in idiopathic Parkinsons disease (PD). The patient presented with unilateral tremor‐dominant parkinsonism. Bilateral STN stimulation was carried out 7 years later due to significant disease progression and severe motor fluctuations. The patient exhibited bilateral improvements in rigidity and bradykinesia both intraoperatively and postoperatively. The patient died 2 months later from aspiration pneumonia. Neuropathological examination confirmed both the diagnosis of PD and the electrode placements. The tip of the left electrode was located medially and posteriorly in the left STN and the tip of the right electrode entered the base of the thalamus/zona incerta immediately above the right STN. Tissue changes associated with the subthalamic electrode tracts included mild cell loss, astrogliosis, and some tissue vacuolation. Our postmortem analysis indicates little tissue damage associated with STN stimulation for PD.

Xanthomatous pituitary lesions: a report of two cases and review of the literature.

We describe two young men with cystic pituitary enlargement on magnetic resonance imaging (MRI) causing hypopituitarism. The first patient presented acutely unwell with headache and vomiting associated with anterior and posterior pituitary dysfunction. The second patient presented with hypopituitarism after a long history of hypogonadism. In both cases yellow/brown fluid was found at surgery and histological examination revealed inflammatory infiltrate with foamy histiocytes, lymphocytes and multinucleated giant cells containing cholesterol clefts. Full recovery of pituitary function occurred after surgery in the first but not the second patient. The first case is the first documented case of xanthomatous hypophysitis with recovery of pituitary function following surgery. The cases differed in duration of disease, as indicated by the long history of symptoms, the histological finding of marked fibrosis and the lack of recovery of pituitary function in the second. Xanthomatous pituitary lesions categorized in the literature as xanthomatous hypophysitis, xanthogranulomatous hypophysitis and xanthogranuloma of the sellar region have overlapping histological features. Our two cases revealed histological features that do not fit completely into any of the categories but share features of all three. These findings suggest that the various xanthomatous lesions of the sellar region may be a spectrum of a common inflammatory process rather than distinct pathological entities.

Radical excision of craniopharyngioma by the temporal route: A review of 50 patients

Attempts at radical excision of craniopharyngioma have been made increasingly possible by progress in neuroradiological imaging and the use of microscopic technique. Between 1977 and 1990, 50 patients of The National Hospital for Neurology and Neurosurgery, London, have undergone radical surgical excision of craniopharyngioma by the temporal route, with a small anterior temporal resection. Surgical mortality was 4%. Thirty-eight (76%) patients remain well at average follow-up of 30 months; 15% had major complications (hypothalamic damage, subdural haematoma, scalp collections requiring shunt drainage). There were three recurrences in those patients where the initial operations were considered as complete microscopic excision. It is concluded that maximal control of tumour recurrence by removal of all tumour accessible and visible to the surgical microscope is best achieved by a radical excision at the first operation.

Lesion of thalamic centromedian-parafascicular complex after chronic deep brain stimulation

A patient with PD who exhibited disabling tremor and prominent dyskinesia underwent deep brain stimulation (DBS) of the left thalamic ventral intermediate nucleus. The electrode migrated and was replaced but with suboptimal clinical response. Two years later, postmortem analysis found the second electrode tip had entered the thalamic centromedian–parafascicular complex. There was a small thalamotomy and cell loss exceeding that found in PD. Thalamic damage may occur in association with DBS for PD.

Image directed stereotactic surgery for brain stem lesions

SummaryAdvances in neurological imaging may have increased the diagnostic accuracy and the detection rate of intrinsic brain stem lesions, but a histological diagnosis is still an essential requirement for rational and appropriate management. Open exploration allows biopsy and resection in cases where an exophytic component is present. The surgical inaccessibility and the resultant morbidity of these approaches, however, associated with a low diagnostic yield in cases with no visible surface abnormality, are important limiting factors.A series of 45 brain stem lesions stereotactically approached with CT or MRI guidance is presented. A transcortical frontal pre-coronal trajectory was used in all of them. Haematoma was preoperatively diagnosed in 10 cases and the procedure was for therapeutic aspiration. Of 35 cases where the diagnosis was uncertain, although intrinsic tumour was suspected, positive results were obtained in 33, while unexpected findings of granuloma, lymphoma, angioma, leucoencephalopathy, vasculitis and radiation necrosis were found in over 10% of the cases. There were no operative deaths and the morbidity was low. In no case was there a permanent neurological deterioration directly related to the procedure, although there was a transient deterioration in two patients and one patient required early reaspiration of a haematoma.Image directed stereotactic approaches to brain stem lesions can combine a high degree of accuracy (offering positive histological diagnoses) with a low operative morbidity. MRI directed biopsies can complement CT guided ones thus increasing the number of suitable cases and improving the success rate. The frontal precoronal transcortical trajectory provides safe access to the majority of the brain stem targets.

Surgical management of haemangioblastoma of the posterior fossa

SummaryFifty-one cases of posterior fossa haemangioblastoma have been seen in our department over a period of 23 years. Seven cases were associated with spinal cord lesions and one with a supratentorial lesion.There were 22 cases of Lindaus disease (43%). The onset was earlier and recurrences commoner than in isolated cases. In 10 cases the development of new tumours in different parts of the central nervous system (CNS) required re-operation, demonstrating the multicentric nature of this disease.The majority of the tumours occupying the fourth ventricle or medulla oblongata (8 cases) were macroscopically solid and had higher post-operative morbidity than the cystic tumours in the cerebellum.The recent development of magnetic resonance imaging (MRI) provides accurate anatomical information of the lesions (especially those of the brain stem and spinal cord) even while asymptomatic. The brilliant enhancement of these tumours on MRI with Gadolinium-diethyline-triamine-pentaacetic acid (Gd-DTPA) has proved to be particularly useful.

Deep brain stimulation for Parkinson’s disease: Australian referral guidelines ☆

The advent of deep brain stimulation (DBS) has been an important advance in the treatment of Parkinsons disease (PD). DBS may be employed in the management of medication-refractory tremor or treatment-related motor complications, and may benefit between 4.5% and 20% of patients at some stage of their disease course. In Australia, patients with PD are reviewed by specialised DBS teams who assess the likely benefits and risks associated with DBS for each individual. The aim of these guidelines is to assist neurologists and general physicians identify patients who may benefit from referral to a DBS team. Common indications for referral are motor fluctuations and/or dyskinesias that are not adequately controlled with optimised medical therapy, medication-refractory tremor, and intolerance to medical therapy. Early referral for consideration of DBS is recommended as soon as optimised medical therapy fails to offer satisfactory motor control.

Stereotactic biopsy of cerebral lesions in patients with AIDS

Central nervous system involvement with AIDS is not uncommon. The indications and timing of brain biopsy remains controversial. Stereotactic CT-guided biopsy offers a safe and effective means of establishing a diagnosis in any patient with a cerebral mass lesion and has less morbidity and mortality than freehand biopsy or exploratory craniotomy. Eleven patients with AIDS have undergone CT-directed stereotactic biopsy between May 1987 and November 1990 with one death from intracerebral haemorrhage. Histological diagnosis of the biopsy specimens showed multifocal leucoencephalopathy, toxoplasmosis, lymphoma and non-specific changes. Biopsy is recommended for patients with an atypical presentation, negative serology, progressive clinical deterioration and differential response of lesions to empirical therapy.

KRN8602 (MX2-Hydrochloride): An Active New Agent for the Treatment of Recurrent High-Grade Glioma

PURPOSE To assess the efficacy and toxicity of KRN8602 when administered as an intravenous bolus to patients with recurrent high-grade malignant glioma. PATIENTS AND METHODS Patients with recurrent or persistent anaplastic astrocytoma or glioblastoma multiforme who had not received recent chemotherapy or radiotherapy and were of good performance status (Eastern Cooperative Oncology Group score < or = 2) were treated with an intravenous bolus of 40 mg/m(2) KRN8602 every 28 days. Tumor responses were assessed radiologically and clinically after every second cycle of therapy. Treatment was continued until documented progression or a total of six cycles. RESULTS A median of three cycles (range, one to six cycles) of KRN8602 was administered to 55 patients, 49 of whom received at least two cycles and were, therefore, assessable for response. The overall response rate (disease stabilization or better) was 43% (95% confidence interval, 29% to 58%). There were three complete responses, one partial response, seven minor responses, and 10 patients with stable disease. The median time to progression was 2 months (range, 1.5 to 37 months) and overall survival was 11 months (range, 1.5 to 40 months). Neutropenia was the most common toxicity, although it was generally of brief duration, and there were only seven episodes of febrile neutropenia in 176 cycles delivered. Nonhematologic toxicity was mostly gastrointestinal (nausea and vomiting, diarrhea) and events were grade 2 or lower except for a single episode of grade 3 vomiting. CONCLUSION KRN8602 is an active new agent with minimal toxicity in the treatment of relapsed or refractory high-grade glioma. Further studies with KRN8602 in combination with other cytotoxics and in adjuvant treatment of gliomas are warranted.