The Spinal Tap: A New Look at an Old Test

Marton, Keith I.

doi:10.7326/0003-4819-104-6-840

Cited by 145 publications

(50 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…37 Overall a traumatic tap with a significant amount of blood can be expected in about 14-20% of standard LPs. 8,24,38,39 Importantly, this figure increases to 72% if a traumatic tap is defined by an erythrocyte count of at least 100 cells (per µL, or × 10 6 /L) in the sample. 38 There is no consensus about the precise definition of a traumatic tap.…”

Section: The Traumatic Tapmentioning

confidence: 99%

“…8,24,38,39 In view of the perceptional limitations of human color vision, with an estimated 80% of critical samples not being seen as yellow, 3 CSF spectrophotometry would be helpful in diagnosing those 9,000 patients who are expected to bleed per year and essential for those 900 who are expected to have a "false negative" normal CT scan.…”

Section: The Size Of the Problemmentioning

confidence: 99%

See 1 more Smart Citation

Spectrophotometry for Cerebrospinal Fluid Pigment Analysis

Petzold

Sharpe²,

Keir³

2006

NCC

View full text Add to dashboard Cite

The use of spectrophotometry for the analysis of the cerebrospinal fluid (CSF) is reviewed. The clinically relevant CSF pigments -oxyhemoglobin and bilirubin -are introduced and discussed with regard to clinical differential diagnosis and potentially confounding variables (the four "T"s or: traumatic tap, timing, total protein and total bilirubin). The practical laboratory aspects of spectrophotometry and automated techniques are presented in the context of analytical and clinical specificity and sensitivity. The perceptual limitations of human color vision are highlighted and the use of visual assessment of the CSF is discouraged in light of recent evidence from a national audit in the United Kingdom. Finally, future perspectives including the need for longitudinal CSF profiling and routine spectrophotometric calibration are outlined.

show abstract

Section: The Traumatic Tapmentioning

confidence: 99%

Section: The Size Of the Problemmentioning

confidence: 99%

Spectrophotometry for Cerebrospinal Fluid Pigment Analysis

Petzold

Sharpe²,

Keir³

2006

NCC

View full text Add to dashboard Cite

show abstract

“…For every ten additional LPs carried out with the LP-first model, there would be one to four additional PLPHs. Other LP complications are extremely rare, 6,20,21 and extremely few, if any, additional complications would be expected.…”

Section: Resultsmentioning

confidence: 99%

“…PLPH is the only complication that occurs with appreciable frequency, and is reported following 5 -36% of LPs. 6,20,21 …”

Section: Methodsmentioning

confidence: 99%

Lumbar Puncture First: An Alternative Model for the Investigation of Lone Acute Sudden Headache

Schull

1999

Academic Emergency Medicine

View full text Add to dashboard Cite

Abstract. Subarachnoid hemorrhage (SAH) is a diagnosis often considered in patients presenting to the ED with acute sudden headaches, but with normal physical examinations. Standard of care today is for these patients to be investigated by noncontrast CT scan followed by lumbar puncture (LP) for negative CTs. However, given that most investigated patients have benign headaches, most of the CT and LP results are normal. The authors studied, by means of a theoretical analysis, the impact of an alternative diagnostic model, in which LP would be the first (and, in most cases, only) diagnostic test for patients suspected of SAH who meet lone acute sudden headache (LASH) criteria. Given reasonable assumptions, for every 100 patients investigated, the ''LP-first'' model would result in 79 to 83 fewer CT scans and only seven to 11 additional LPs, as compared with traditional strategies. Among ED headache patients meeting LASH criteria, the authors believe use of this model could result in more efficient use of resources, minimal additional morbidity, and equal diagnostic accuracy for SAH. Key words: lumbar puncture; headache; subarachnoid hemorrhage; lone acute sudden headache. ACADEMIC EMERGENCY MEDI-CINE 1999; 6:131 -136 N ONTRAUMATIC headache is a common source of ED visits, representing up to 4.5% of presenting complaints.1 Subarachnoid hemorrhage (SAH) is the cause of approximately 1% of all headaches seen in the ED, 1 and up to a third of acute sudden headaches. 2,3Subarachnoid hemorrhage occurs in young people, with a median age of 50 years, and has a 50% mortality at six months.2,4 -6 Among survivors, just over half regain their premorbid neurologic state six months after SAH. 4,6,7 Clearly emergency physicians must maintain a high index of suspicion for SAH and must, quite appropriately, be liberal in initiating investigations for this devastating, but potentially curable, disease.Among Computed tomography scanning alone cannot be relied on to rule out SAH, since its sensitivity at 24 hours varies from 81% to 100%, and decreases rapidly thereafter, 9 -15 even with newergeneration CT scanners.12,15,16 Also, CT sensitivity varies with the neurologic status of the patient; CT is only 86% sensitive in alert patients with SAH, as compared with 99.4% sensitivity in stuporous or comatose patients with SAH. 6,11 Normal CTs, therefore, must be followed by a lumbar puncture (LP). Cerebrospinal fluid (CSF) xanthochromia as detected by spectrophotometry is virtually 100% sensitive for SAH, so long as it is done no earlier than 12 hours following the bleeding, in order to allow enough time for xanthochromia to develop. 13,17 -19 This very high sensitivity of LP decays very slowly, remaining at virtually 100% for two weeks following a hemorrhage. 10,13,17 Given that LASH patients should be investigated for SAH, but that most have benign headaches, a great many negative CT scans and LPs are carried out. Is there a more efficient way to investigate patients meeting LASH criteria? Specifically, could we forgo the CT and pro...

show abstract

“…2 Physician microscopy of CSF samples with normal cell counts has been shown to be unnecessary and wasteful of resources.' Furthermore, if the opening pressure, cell count and protein concentration are all normal, additional procedures are rarely of value.4 CSF cytology is principally useful in the identification of malignant cells, as the cytological changes in inflammatory and other non-neoplastic disorders are non-specific.5 6 The progress of non-neoplastic conditions can be monitored by CSF cell count/ differential, protein and glucose concentrations measured by a biomedical scientist without the necessity of the use of expensive pathologist's time in performing cytology.…”

mentioning

confidence: 99%

Malignant meningitis: a rational approach to cerebrospinal fluid cytology.

MacKenzie

1996

Journal of Clinical Pathology

View full text Add to dashboard Cite

The progress of non-neoplastic conditions can be monitored by CSF cell count/ differential, protein and glucose concentrations measured by a biomedical scientist without the necessity of the use of expensive pathologist's time in performing cytology. Suspected infections require proper microbiological investigation of the CSF6 and identification of organisms in a cytological preparation is probably only an aesthetic reward for the pathologist and contributes little, if anything, to the patient's management. Yet clinicians frequently adopt the "blunderbuss" approach to requesting of laboratory tests on CSF without due regard to the propriety of tests in the clinical circumstances, with cytology, cell count, protein, glucose, oligoclonal bands, and microbiology often being requested routinely, and pathologists often feel a moral obligation to carry out the tests requested, even if this has no rational basis.This study sought to clarify criteria by which the pathologist can decide when CSF cytology is likely to contribute to the patient's management, and minimise the number of unnecessary cytological tests, firstly, by defining under what circumstances malignant cells are likely to be found in the CSF and, secondly, by validating these criteria in practice.Methods From 1980 to 1990, cytology was carried out on all CSF specimens received in the Neuropathology Laboratory of the Walton Centre for Neurology and Neurosurgery, Liverpool. During that period 5808 cytological specimens were received. All of the reports were reviewed and, in CSF samples from 132 patients, cells variously described as "malignant", "atypical" or "suspicious" had been described. All of the cytospin preparations from these patients were re-examined and CSF samples from 54 patients contained cells which were regarded as definitely malignant.The clinical details and histological material (where available) relating to these 54 patients were reviewed in order to (1) confirm that the diagnosis of malignancy on the basis of CSF cytology was correct and (2) identify criteria by which the decision whether or not to perform cytology could be made in the laboratory. To assist in the second objective, cell counts and protein concentrations, available for 29 of the patients, were also utilised.Having established, and implemented, the criteria 100 cases from 1992 to 1993 for which complete clinical records were available, and in which cytology had not been carried out on the basis of these criteria, were randomly selected and thoroughly reviewed to establish whether there was any possibility that a case of malignant meningitis had been missed.

show abstract

The Spinal Tap: A New Look at an Old Test

Cited by 145 publications

References 47 publications

Spectrophotometry for Cerebrospinal Fluid Pigment Analysis

Spectrophotometry for Cerebrospinal Fluid Pigment Analysis

Lumbar Puncture First: An Alternative Model for the Investigation of Lone Acute Sudden Headache

Malignant meningitis: a rational approach to cerebrospinal fluid cytology.

Contact Info

Product

Resources

About