Rates, costs, return to work and reoperation following spinal surgery in a workers' compensation cohort in New South Wales, 2010-2018: a cohort study using administrative data

BACKGROUND

Internationally, elective spinal surgery rates in workers' compensation populations are high, as are reoperation rates, while return-to-work rates following spinal surgery are low. Little information is available from Australia. The aim of this study was to describe the rates, costs, return to work and reoperation following elective spinal surgery in the workers' compensation population in New South Wales (NSW), Australia.

METHODS

This retrospective cohort study used administrative data from the State Insurance Regulatory Authority, the government organisation responsible for regulating and administering workers' compensation insurance in NSW. These data cover all workers' compensation-insured workers in New South Wales (over 3 million workers/year). We identified a cohort of insured workers who underwent elective spinal surgery (fusion or decompression) between January 1, 2010 and December 31, 2018. People who underwent surgery for spinal fracture or dislocation, or who had sustained a traumatic brain injury were excluded. The main outcome measures were annual spinal surgery rates, cost of the surgical episode, cumulative costs (surgical, hospital, medical and physical therapy) to 2 years post-surgery, and reoperation and return-to-work rates 2 years post-surgery.

RESULTS

There were 9343 eligible claims (39.1 % fusion; 59.9 % decompression); claimants were predominantly male (75 %) with a mean age of 43 (range 18 to 75) years. Spinal surgery rates ranged from 15 to 29 surgeries per 100,000 workers per year, fell from 2011-12 to 2014-15 and rose thereafter. The average cost in Australian dollars for a surgical episode was $46,000 for a spinal fusion and $20,000 for a decompression. Two years post-fusion, only 19 % of people had returned to work at full capacity; 39 % after decompression. Nineteen percent of patients underwent additional spinal surgery within 2 years of the index surgery, to a maximum of 5 additional surgeries.

CONCLUSION

Rates of workers' compensation-funded spinal surgery did not rise significantly during the study period, but reoperation rates are high and return-to-work rates are low in this population at 2 years post- surgery. In the context of the poor evidence base supporting lumbar fusion surgery, the high cost, increasing rates, and the increased likelihood of poor outcomes in the workers' compensation population, we question the value of this procedure in this setting.

Perspectives of Interstitial Lung Disease Patients and Carers During COVID-19

Aim To gain an understanding of the impact of COVID-19 on the daily life, healthcare needs, mental wellbeing and outlook of patients with Interstitial Lung Disease (ILD) and their caregivers. Methods ILD patients and caregivers were invited to participate in a quantitative survey. Respondents could self-select to then participate in in-depth structured telephone interviews. Survey data was compared to Department of Health COVID-19 public opinion tracker findings for the comparable time period. Results There were 170 survey respones (111 patients and 59 caregivers) and 14 in-depth interview participants. 32% (n=36) of patients and 42% (n=25) of caregivers expressed extreme worry regarding COVID-19 on a 1-10 scale. 83% (n=92) of patients expressed concern about safe hospital access, 33% (n=37) had received a telephone consultation with their clinician, 43% (n=48) reported test delays, 47% (n=52) were exercising less, 23% (n=26) reported worse sleep and 15% (n=17) reported being financially worse off. Carers reported that sleep was worse for 58% (n=34), 42% (n=25) reported being worse off financially, and 40% (n=24) reported a worse diet. Worry (66%, n=39), stress (51%, n=30), anxiety (49%, n=29) were commonly reported by carers. Discussion ILD patients and caregivers reported higher levels of worry regarding COVID-19 compared to the general public. Alternative pathways for quality ILD patient care and interventions to reduce the burden of care on ILD caregivers are required.

Imaging post liver transplantation part I: vascular complications

Liver transplantation continues to rise in frequency, with over 1,000 procedures performed in the UK in 2018. Complications are increasingly uncommon but when they occur, early recognition and intervention is vital to save grafts. Imaging after the perioperative period is often performed at patients' local hospitals meaning that all radiologists and sonographers need to have an understanding of how to assess a transplant liver. Part I of this series will focus on vascular complications, including the normal postoperative vascular anatomy following liver transplantation, normal post-transplantation vascular imaging findings and abnormal findings that may prompt further investigation. Vascular complications following liver transplantation will be illustrated using a collection of cases.

The impact of violence reduction initiatives on emergency department attendance

BACKGROUND

Recent violence reduction initiatives in Glasgow have led to a reduction in recorded levels of violent crime.(1) This study evaluates the impact of these initiatives on assault-related emergency department attendances and admissions.

METHODS

A retrospective observational study conducted in Glasgow Royal Infirmary's emergency department comparing assault-related emergency department attendances and hospital admissions over two 30-day study periods (April 2010 and April 2012). The primary outcome measure was the change in assault-related emergency department attendances. The secondary outcome measure was the impact on assault-related hospital and critical care admissions.

RESULTS

In April 2010, there were 6098 emergency department attendances, 301 (4.9%) were due to assault. In April 2012, there were 7236 emergency department attendances, 263 (3.6%) were due to assault, representing a significant reduction in assault-related attendances (p < 0.01). There were significant reductions in level 1 admissions 2010 n = 56 (19.2%), 2012 n = 36 (14.0%) p = 0.04 and critical care admissions, 2010 n = 5 (1.7%), 2012 n = 1 (0.4%) p = 0.04.

CONCLUSIONS

Violence reduction initiatives in Glasgow have contributed to a reduction in assault-related emergency department attendance at Glasgow Royal Infirmary. The reduction in hospital admissions, in particular critical care admissions, suggests a reduction in morbidity and cost to the National Health Service.

Spontaneous pancreatic pseudocyst-portal vein fistula: a rare and potentially life-threatening complication of pancreatitis

Pseudocyst formation following acute and chronic pancreatitis is a well known complication. A pancreatic pseudocyst fistulating into the portal vein is a rare and potentially fatal complication. We report a case of pancreatic pseudocyst – portal vein fistula, which was managed with a conservative approach.

Spontaneous pancreatic pseudocyst-portal vein fistula: a rare and potentially life-threatening complication of pancreatitis

Pseudocyst formation following acute and chronic pancreatitis is a well known complication. A pancreatic pseudocyst fistulating into the portal vein is a rare and potentially fatal complication. We report a case of pancreatic pseudocyst - portal vein fistula, which was managed with a conservative approach.

Enhanced frontal function in Parkinson's disease

We investigated the role of dopamine in working memory by examining effects of withdrawing dopaminergic medication in patients with Parkinson's disease. Resistance to distraction during a delayed response task was abnormally enhanced in Parkinson's disease patients OFF medication relative to controls. Conversely, performance on a backward digit span test was impaired in these same Parkinson's disease patients OFF medication. Dopaminergic medication reinstated susceptibility to distraction and backward digit span performance, so that performance of Parkinson's disease patients ON medication did not differ from that of controls. We hypothesize that the enhanced distractor resistance and impaired backward digit span in Parkinson's disease reflects low dopamine levels in the striatum, and perhaps upregulated frontal dopamine levels. Dopaminergic medication may reinstate distractibility by normalizing the balance between striatal and prefrontal dopamine transmission.

Hemodynamics and bleb formation in intracranial aneurysms

BACKGROUND AND PURPOSE

Intracranial aneurysms with irregular shapes and blebs or secondary outpouchings have been correlated with increased rupture risk. The purpose of this study was to investigate possible associations between the local hemodynamics and the formation of blebs in cerebral aneurysms.

MATERIALS AND METHODS

Computational models of 20 cerebral aneurysms harboring 30 well-defined blebs were constructed from 3D rotational angiographies. Models representing the aneurysm before bleb formation were constructed by virtually removing the blebs from the anatomic models. Computational fluid dynamics simulations of the aneurysm before and after bleb formation were performed under pulsatile flows. Flow and WSS visualizations were used to analyze the local hemodynamics in the region of the aneurysm that developed the bleb.

RESULTS

Most blebs (80%) occurred at or adjacent to the aneurysm region with the highest WSS before bleb formation, and near the flow impaction zone. Most blebs (83%) were found in regions of the aneurysm previously subjected to high or moderate WSS and progressed to low WSS states after the blebs were formed. Most blebs (77%) were aligned or adjacent to the inflow jet, whereas 17% were aligned with the outflow jet, and only 6% were not aligned with the flow direction. In addition, 90% of the aneurysms had maximal WSS higher than or similar to the WSS in the parent artery.

CONCLUSIONS

Blebs form at or adjacent to regions of high WSS and are aligned with major intra-aneurysmal flow structures. Formation of blebs results in a lower WSS state with formation of a counter current vortex. These findings imply that locally elevated WSS could contribute to the focalized wall damage that formed these structures.

The safety and tolerability of duloxetine in depressed elderly patients with and without medical comorbidity

AIM AND METHODS

The impact of medical comorbidity on the efficacy and tolerability of duloxetine in elderly patients with major depressive disorder (MDD) was investigated in this study. Data were obtained from a multicentre, randomised, double-blind, placebo-controlled study in 311 patients with MDD aged 65-89. The primary outcome measure was a prespecified composite cognitive score based on four cognitive tests: (i) Verbal Learning and Recall Test; (ii) Symbol Digit Substitution Test; (iii) 2-Digit Cancellation Test and (iv) Letter-Number Sequencing Test. Secondary measures included the Geriatric Depression Scale (GDS), 17-Item Hamilton Depression Scale (HAMD17), Clinical Global Impression-Severity (CGI-S) Scale, Visual Analogue Scale (VAS) for pain and 36-Item Short Form Health Survey (SF-36). Tolerability measures included adverse events reported as the reason for discontinuation and treatment-emergent adverse events (TEAEs). The consistency of the effect of duloxetine vs. placebo comparing patients with and without medical comorbidity (vascular disease, diabetes, arthritis or any of these) was investigated.

RESULTS

Overall, duloxetine 60 mg/day demonstrated significantly greater improvement compared with placebo for the composite cognitive score, GDS and HAMD17 total scores, CGI-Severity, HAMD17 response and remission rates, and some of the SF-36 and VAS measures. There were few significant treatment-by-comorbidity subgroup interactions for these efficacy variables, or for adverse events reported as the reason for discontinuation and common TEAEs.

CONCLUSIONS

The present analyses suggested that the efficacy of duloxetine on cognition and depression in elderly patients, and its tolerability, were not largely affected by the comorbidity status. These results further support the use of duloxetine in elderly patients with MDD.

Preoperative staging of rectal cancer by MRI; results of a UK survey

AIM

To determine current day-to-day practice of and access to preoperative MRI for patients with rectal cancer in the UK, with the aim of identifying constraining factors.

MATERIALS AND METHODS

A questionnaire asking for details of rectal cancer workload, multidisciplinary team (MDT) practice, preoperative MRI, the use of alternative imaging methods where appropriate, and an assessment of local access to MRI, was mailed to 283 UK departments of radiology. Replies were received from 142 departments (50.2% response rate). These were collated and response frequencies were determined.

RESULTS

According to their replies, 135 (95%) of respondents always discussed rectal cancer cases within the context of an MDT, usually including a radiologist. Only 49% of respondents attempted to offer preoperative MRI to all rectal cancer patients, and 35% of respondents used MRI in less than 25% of cases. Of the 142 respondents, 73 (51%) felt their practice was currently constrained by lack of MR resources. The most frequently cited constraint was an available but over-subscribed MRI scanner. Limited radiology manpower was the next most frequently cited constraint. A significant minority stated that no MRI scanner was available.

CONCLUSIONS

The MDT is a well established forum for the discussion of patients with rectal cancer, and a radiologist is usually involved. However, in the face of current guidelines, less than 50% of the units studied were able to offer preoperative MRI to all of their rectal cancer cases. Improved access to MRI and increased radiological manpower are necessary if current management guidelines are to be observed.

Association of emotional intelligence with alexithymic characteristics

We examined the association of emotional intelligence and alexithymic characteristics as the personality trait in cohorts of 267 college students and 398 psychiatric outpatients. Score on the Toronto Alexithymia Scale were significantly correlated with those on the Emotional Intelligence Scale, suggesting that alexithymic characteristics are related to lower emotional intelligence. In conclusion, these data suggest that emotional intelligence overlaps with alexithymia.

Validity and reliability of the Japanese version of the Emotional Intelligence Scale among college students and psychiatric outpatients

We examined the validity and reliability of the Japanese version of the Emotional Intelligence Scale in two samples of 267 college students and 398 psychiatric outpatients. Suitable validity and reliability of this scale were suggested by high correlations with scores on the NEO Personality Inventory, adequate internal consistency, and relatively high test-retest correlations. The Emotional Intelligence Scale seems suitable for both clinically distressed populations as well as comparative groups such as college students.

Adherence and invasion studies of Candida albicans strains, using in vitro models of esophageal candidiasis

The adherence of clinical and commensal isolates and reference collection strains of Candida albicans to a human esophageal cell monolayer (HET1-A) and reconstituted human esophageal tissue was compared. Isolates from patients with a severe form of esophageal candidiasis or candidemia adhered to HET1-A cells to a significantly greater extent than did isolates from patients with mild esophageal candidiasis or commensal and reference collection strains. In addition, C. albicans strain SSK21, which lacks the ssk1 response regulator gene of a 2-component signal transduction pathway, adhered less readily to the HET1-A cells than did parental cells or a gene-reconstituted strain. In a reconstituted esophageal tissue model, all clinical strains but not commensal or reference collection strains penetrated the epithelium, albeit at different rates. Hyphal formation following yeast cell adherence to the esophageal tissue was a requirement for invasion. Scanning electron microscopy was also used to confirm the colonization of the esophageal tissues by various strains. These studies indicate that both the HET1-A and the reconstituted esophageal tissue models can be used as in vitro targets to evaluate the adherence phenotype and invasiveness of C. albicans strains.

Managing malignant spinal cord compression

BACKGROUND

Spinal malignancy can present as low back pain and accounts for most cases of spinal cord compression (SCC).

OBJECTIVE

To assist the clinician in the diagnosis of malignant SCC and to increase awareness of various treatment modalities. A clinical approach for the workup of patients with 'metastatic carcinoma of unknown primary' is also outlined.

DISCUSSION

It is important to diagnose SCC early and initiate urgent treatment to obtain optimum patient outcomes. Further management includes workup for the primary tumour source if unknown.

Caregiver quality of life after autologous bone marrow transplantation

Bone marrow transplantation (BMT) is a unique cancer therapy characterized by its novelty, intensity, and toxicity. Although families have been identified as having a critical influence on patient adaptation during the acute phase of BMT, minimal attention has been paid to their experiences during extended survivorship. This article reviews findings from a descriptive study on quality of life in primary caregivers of adult autologous bone marrow transplantation (AuBMT) survivors after acute hospitalization. Caregiver perceptions of their survival are delineated in an effort to characterize the dynamics of family recovery after BMT. Specifically, caregivers of AuBMT survivors require ongoing assistance to maintain their primary support role after BMT.

Avirulence of Candida albicans CaHK1 mutants in a murine model of hematogenously disseminated candidiasis

Deletion of both alleles of the Candida albicans CaHK1 gene, which causes cells to flocculate when grown at pH 7.5, a pH comparable to that of mammalian blood, abolishes the ability of the yeast to establish a successful infection in a murine model of hematogenously disseminated candidiasis. Within 72 h all mice inoculated with the parental C. albicans strain had died. The mice infected with either the heterozygote or revertant strain, either of which harbors only one functional CaHK1 allele, also succumbed to the infection, although survivors were observed for up to 16 days postinfection. However, mice inoculated with the Deltacahk1 null strain survived for the course of the infection. These results indicate that CaHK1 is required for the virulence of C. albicans in a murine model of hematogenously disseminated candidiasis. In contrast, CaHK1 is not required for the virulence of C. albicans in a rat model of vaginal candidiasis.

Enforcement of minor tobacco laws: Wisconsin, 1996

The objective of this project was to profile the statewide enforcement of laws prohibiting sales of tobacco to minors and purchasing/possession of tobacco by minors in 1996. A sample of Wisconsin cities or villages (n = 86) were surveyed on adoption of pertinent state statutes as local ordinances and the number of recorded violations. About 70% of municipalities have passed illegal sales ordinances and about 80% have passed purchase/possession ordinances. Over 6,000 citations were issued to minors in 1996 for purchase/possession of tobacco and 67 citations were issued for illegal sales to minors. By extrapolation, we estimate that there is approximately one commercial selling citation issued for every 112,000 packs of cigarettes sold to minors. We discuss this disparity and submit that a shift in enforcement, to commercial sellers, is needed to help reduce the increasing use of tobacco by minors.

The Dublin outcome for low birth-weight infants

This report describes outcomes for all infants with birth weight 501-1750 grams born in the three major maternity hospitals in Dublin between 1.1.90 to 31.12.91. 37,958 mothers delivered 38,498 infants during this period, consisting of approximately 36% of all deliveries in Ireland. 633 (1.6%) of all infants born weighed 501-1750 grms. 102 (16%) were stillborn and 28 of the 531 live born infants had lethal malformations. 30% of women received two or more doses of antenatal steroids before delivery and a highly significant negative correlation occurred between the need for ventilation after birth and antenatal steroids. 56.4% of babies were delivered by caesarean section as compared with 10.8% of the hospital population. Of 503 liveborn infants without lethal malformation. 426 (85%) survived to 28 days and 419 (83%) to discharge home. 15% were growth retarded. 46% of infants were ventilated, mean duration of ventilation was 7 days. 25% of infants had an intraventricular haemorrhage, 10% necrotising enterocolitis and 19% culture proven sepsis. 15% of survivors developed broncho pulmonary dysplasia and 12% retinopathy of prematurity. This paper describes important information for mortality, morbidity and interventions among a large population of low birth weight infants in Ireland and can be used as a basis against which to compare future alterations in practice. It demonstrates a clear benefit for antenatal steroids in decreasing the need for ventilation and the importance of ensuring their utilisation antenatally where possible.

Computer-assisted instruction using electronic mail

A major challenge to nursing staff development departments is how to reach individual staff members with new information in a limited period of time. Attendance at classroom instruction is not always feasible. The use of electronic mail to provide instruction to learners can be an effective teaching strategy. Advantages are immediate accessibility to the learner and the opportunity to tailor the program to meet specific hospital requirements or individual learning needs. Tips on how to develop and send instructional modules through electronic mail are included in this article.

Tobacco acquisition practices of adolescents in two Wisconsin communities

More than 2,000 students in two Wisconsin communities were surveyed on their tobacco use and acquisition habits. The results indicate a defined pattern of acquisition across the three grade levels surveyed. Eighth grade tobacco users buy or "bum" tobacco from friends but also use a wide variety of methods and sources. Tenth and 12th grade tobacco users primarily purchase tobacco from businesses. About one third of 8th grade tobacco users regularly buy from vending machines and almost half of the 8th and 10th grade tobacco users in one of the communities have shoplifted tobacco during the past year, with 12% most often obtaining tobacco in this manner. These patterns of acquisition may have a contributory effect on the high prevalence of adolescent tobacco use reported in both communities. The results argue for meaningful enforcement of laws prohibiting tobacco sales to minors and the elimination of self-service sales of tobacco products.

Fatal pulmonary embolism by tumor during resection of a choroid plexus papilloma: case report

A unique case of pulmonary embolization of a tumor in a patient undergoing resection of a choroid plexus papilloma is presented. The possible mechanisms by which this occurs are discussed, as are the implications of the possible seeding of the tumor to distal sites by microembolization.

Hydrocephalus and pseudotumour cerebri in the mucopolysaccharidoses

This paper reports two cases of cerebrospinal fluid circulation disorder in children with mucopolysaccharidosis. One patient developed pseudotumour cerebri and the other communicating hydrocephalus. It is suggested that both have a similar underlying abnormality of cerebrospinal fluid absorption with different modes of presentation.

Scaphoid fracture: a new method of assessment

The value of colour flow Doppler ultrasound scanning in patients with suspected acute carpal scaphoid fracture has been examined. A prospective study of 78 patients with signs and symptoms of carpal scaphoid injury was undertaken over a period of 6 months. Both wrists of all patients were scanned within 12-72 h of injury. The radial artery and carpal scaphoid bone contours are visible using this type of imaging technique. The distance between the medial wall of the radial artery and the outer cortex of the scaphoid waist was measured. The scaphoid index is described and was calculated from this measurement. Patients were managed without knowledge of the ultrasound imaging result, using plain radiographs and clinical examination as the standard for determining the presence of a scaphoid fracture. All patients were followed to the resolution of symptoms. All 12 patients who were subsequently considered to have scaphoid fractures were identified using this imaging technique within 12-72 h after injury. We conclude that this imaging may be useful in the assessment of patients with carpal scaphoid fracture. It can be used early, as a supplementary investigation, in patients with suspected carpal scaphoid fracture in whom the initial plain radiographs are normal.

Availability of cigarettes to under-age youth in Fond du Lac, Wisconsin

Ninety-three percent of surveyed Fond du Lac School District students reported cigarettes as being "fairly easy" to "easy" to obtain. Easy access to cigarettes from retail outlets may be instrumental in the inordinately high local prevalence of under-age smoking. Fourteen-year-old youths were trained to attempt purchases of cigarettes from all cigarette outlets in the city of Fond du Lac. Information relating to the purchase attempts was recorded and analyzed. Our 60% purchase success rate stems from purchases at 77% of vending machines and 43% of over-the-counter outlets. Sales from taverns accounted for approximately 25% of the totals. Our results are consistent with other studies and argue for retailer education and systematic enforcement of policies that address underage purchase of cigarettes from licensed outlets including those that otherwise proscribe minors from entering.

Effect of preanesthetic medication on ease of endoscopic intubation of the duodenum in anesthetized dogs

The effects of preanesthetic medication on ease of duodenal endoscopic intubation in dogs was evaluated. One of 12 combinations of preanesthetic medications (using atropine, glycopyrrolate, morphine, meperidine, acepromazine, and 0.9% NaCl solution) was administered IM to each of 12 dogs in a trial. Twelve endoscopic trials were performed so that each dog received each treatment combination once. Anesthesia was induced with thiamylal administered IV and maintained with halothane vaporized in oxygen. Electrocardiographic recordings, indirect blood pressure measurements, end-tidal carbon dioxide partial pressures, and halothane concentrations were monitored during the anesthetic period. The ease with which the fiberoptic endoscope was passed into the proximal portion of the duodenum was qualitatively score on the basis of time and maneuvering effort. None of the preanesthetic combinations made intubation of the duodenum significantly easier than that with 0.9% NaCl solution (control). Only the combination of morphine and atropine induced gastro-pyloric conditions that resulted in significantly higher (more difficult) endoscopic scores than those after preanesthetic medication with 0.9% NaCl solution.

The binding of the fluorescent ATP analogue 2'(3')-trinitrophenyladenosine-5'-triphosphate to rat liver fatty acid-binding protein

The less polar fluorescent analogue of ATP, 2'(3')-trinitrophenyl-5'-triphosphate bound to rat liver fatty acid-binding protein with high affinity (Kd 6.3 x 10(-6) M) and 1:1 molar stoichiometry. This probe bound to the fatty acid binding site of the protein and was displaced by oleic acid and oleoyl CoA. High concentrations of ATP did not cause significant displacement of the fluorescent ATP analogue. Since the anionic part of this molecule is the triphosphate group it is difficult to envisage this group being accommodated at an anion binding site within the non-polar core of this protein as is the case with other fatty acid binding proteins. Therefore it is anticipated that the ligand must bind to liver fatty acid-binding protein with this triphosphate group surface exposed. Caution must be exercised when using the more hydrophobic fluorescent analogue of ATP to investigate the ATP binding properties of proteins.

Hydrocephalus, lumbar canal stenosis and Maroteaux-Lamy syndrome (mucopolysaccharidosis type 6). Case report

A case of communicating hydrocephalus and lumbar canal stenosis in a child with mucopolysaccharidosis type 6 is reported. We review the literature and discuss the aetiology of communicating hydrocephalus in this condition.

Precipitants of violence in a psychiatric inpatient setting

Data gathered from the medical record and in interviews with staff and patients in an inpatient psychiatric setting at a Veterans Affairs medical center were used to examine events preceding 73 episodes in which patients were placed in four-point restraints. The behaviors leading to restraint included physical aggression, verbal threats, and threats with an object as a weapon. These behaviors were more likely to relate to external situations than to the patient's internal psychiatric symptoms. Staff were most frequently the target of patients' aggression, and patients were more likely to view the events leading to restraint as conflict with staff. No differences in the subsequent number of restraint episodes or hours in restraints were found between patients with positive and negative responses to the index restraint episode.

Corneal asphericity and refractive error

The relationship between corneal curvature measured by classical keratometry and refractive error raises the question of a possible systematic relationship between refractive error and the degree of corneal asphericity. A recomputation and analysis of previously published data leads to the conclusion that the different refractive groups have similar values of the parameter 'p' and differ only in the apical radius of the cornea.

The measurement of the corneal ellipse for the contact lens practitioner

A keratometric instrument is described which can be used to measure the p-value of the corneal ellipse. The performance of the instrument is compared with that of the Guillbert Routit topographical keratometer and the Wesley Jessen P. E. K. The application of the p-value to contact lens fitting is discussed.