Outcomes After Implementation of a Benzodiazepine-Sparing Alcohol Withdrawal Order Set in an Integrated Health Care System

Importance

Alcohol withdrawal syndrome (AWS) is a common inpatient diagnosis managed primarily with benzodiazepines. Concerns about the adverse effects associated with benzodiazepines have spurred interest in using benzodiazepine-sparing treatments.

Objective

To evaluate changes in outcomes after implementation of a benzodiazepine-sparing AWS inpatient order set that included adjunctive therapies (eg, gabapentin, valproic acid, clonidine, and dexmedetomidine).

Design, Setting, and Participants

This difference-in-differences quality improvement study was conducted among 22 899 AWS adult hospitalizations from October 1, 2014, to September 30, 2019, in the Kaiser Permanente Northern California integrated health care delivery system. Data were analyzed from September 2020 through November 2021.

Exposures

Implementation of the benzodiazepine-sparing AWS order set on October 1, 2018.

Main Outcomes and Measures

Adjusted rate ratios for medication use, inpatient mortality, length of stay, intensive care unit admission, and nonelective readmission within 30 days were calculated comparing postimplementation and preimplementation periods among hospitals with and without order set use.

Results

Among 904 540 hospitalizations in the integrated health care delivery system during the study period, AWS was present in 22 899 hospitalizations (2.5%), occurring among 16 323 unique patients (mean [SD] age, 57.1 [14.8] years; 15 764 [68.8%] men). Of these hospitalizations, 12 889 (56.3%) used an order set for alcohol withdrawal. Among hospitalizations with order set use, any benzodiazepine use decreased after implementation from 6431 hospitalizations (78.1%) to 2823 hospitalizations (60.7%) (P < .001), with concomitant decreases in the mean (SD) total dosage of lorazepam before vs after implementation (19.7 [38.3] mg vs 6.0 [9.1] mg; P < .001). There were also significant changes from before to after implementation in the use of adjunctive medications, including gabapentin (2413 hospitalizations [29.3%] vs 2814 hospitalizations [60.5%]; P < .001), clonidine (1476 hospitalizations [17.9%] vs 2208 hospitalizations [47.5%]; P < .001), thiamine (6298 hospitalizations [76.5%] vs 4047 hospitalizations [87.0%]; P < .001), valproic acid (109 hospitalizations [1.3%] vs 256 hospitalizations [5.5%]; P < .001), and phenobarbital (412 hospitalizations [5.0%] vs 292 hospitalizations [6.3%]; P = .003). Compared with AWS hospitalizations without order set use, use of the benzodiazepine-sparing order set was associated with decreases in intensive care unit use (adjusted rate ratio [ARR], 0.71; 95% CI, 0.56-0.89; P = .003) and hospital length of stay (ARR, 0.71; 95% CI, 0.58-0.86; P < .001).

Conclusions and Relevance

This study found that implementation of a benzodiazepine-sparing AWS order set was associated with decreased use of benzodiazepines and favorable trends in outcomes. These findings suggest that further prospective research is needed to identify the most effective treatments regimens for patients hospitalized with alcohol withdrawal.

Successful Emergency Treatment of Refractory Neuroleptic Malignant Syndrome With Electroconvulsive Therapy and a Novel Use of Dexmedetomidine: A Case Report From California in the Era of COVID-19

ABSTRACT

We describe the case of a patient, hospitalized in a California community medical ICU for over a month, with severe neuroleptic malignant syndrome (NMS), unresponsive to medical management, but responsive to electroconvulsive therapy (ECT). We discuss the medical, logistical, and legal challenges in providing ECT in this setting. We also describe a previously unpublished use of dexmedetomidine, which aided in the safe and rapid reduction of benzodiazepines and permitted a successful ECT course. The rapid delivery and efficacy of ECT were essential because of the burgeoning coronavirus pandemic. The patient's treatment required exemplary efforts by providers across multiple disciplines, ongoing medicolegal consultation with the county mental health medical director, as well as consultation with expert members of the International Society for ECT and Neurostimulation. We conclude with a discussion of the unique challenges of providing emergency ECT to patients in California, including during a serious pandemic, when courts are closed. This case illustrates the importance of cultivating and maintaining high-quality ECT expertise in community hospitals and keeping ECT services available even during pandemics. Also, this case demonstrates that ECT is not "merely an elective procedure" but a vital, life-saving treatment, even during the era of COVID-19. To our knowledge, this is the first such published case of emergency ECT performed in California.

Monitoring wild pig populations: a review of methods

Wild pigs (Sus scrofa) are widespread across many landscapes throughout the world and are considered to be an invasive pest to agriculture and the environment, or conversely a native or desired game species and resource for hunting. Wild pig population monitoring is often required for a variety of management or research objectives, and many methods and analyses for monitoring abundance are available. Here, we describe monitoring methods that have proven or potential applications to wild pig management. We describe the advantages and disadvantages of methods so that potential users can efficiently consider and identify the option(s) best suited to their combination of objectives, circumstances, and resources. This paper offers guidance to wildlife managers, researchers, and stakeholders considering population monitoring of wild pigs and will help ensure that they can fulfill their monitoring objectives while optimizing their use of resources.

Working in collaboration with young people and health professionals. A staged approach to the implementation of a randomised controlled trial

ASyMS© is an Advanced Symptom Management System utilising mobile phone technology to monitor chemotherapy-related symptoms and promote self-care. It was first developed with an adult cancer population and is now being evaluated with young people through an iterative development process. ASyMS© involves patients recording and sending symptom reports to the hospital and receiving tailored self-care advice. Health professionals are alerted when severe symptoms are reported. Three phases of the ASyMS©-YG (young people) study are complete. Phase 1 involved young people identifying the symptoms to be assessed. Phase 2 involved young people testing the symptom report system, and ascertaining young people’s, parents’ and professionals’ perceptions of ASyMS©-YG. This paper reports on Phase 3, in which the system was developed further in preparation for a randomised controlled trial (RCT). Health professionals devised an alert system based on risk modelling side-effect severity, and young people and professionals developed self-care advice. A pilot study was conducted to test the alert system and study design in readiness for a definitive RCT. The contribution young people and professionals have made to this project is invaluable in evaluating the practical effectiveness of ASyMS©-YG and ensuring the intervention is acceptable and works in everyday practice.

Evaluation of a mobile phone-based, advanced symptom management system (ASyMS) in the management of chemotherapy-related toxicity

OBJECTIVES

To evaluate the impact of a mobile phone-based, remote monitoring, advanced symptom management system (ASyMS) on the incidence, severity and distress of six chemotherapy-related symptoms (nausea, vomiting, fatigue, mucositis, hand-foot syndrome and diarrhoea) in patients with lung, breast or colorectal cancer.

DESIGN

A two group (intervention and control) by five time points (baseline, pre-cycle 2, pre-cycle 3, pre-cycle 4 and pre-cycle 5) randomised controlled trial.

SETTING

Seven clinical sites in the UK; five specialist cancer centres and two local district hospitals.

PARTICIPANTS

One hundred and twelve people with breast, lung or colorectal cancer receiving outpatient chemotherapy.

INTERVENTIONS

A mobile phone-based, remote monitoring, advanced symptom management system (ASyMS).

MAIN OUTCOME MEASURES

Chemotherapy-related morbidity of six common chemotherapy-related symptoms (nausea, vomiting, fatigue, mucositis, hand-foot syndrome and diarrhoea).

RESULTS

There were significantly higher reports of fatigue in the control group compared to the intervention group (odds ratio = 2.29, 95%CI = 1.04 to 5.05, P = 0.040) and reports of hand-foot syndrome were on average lower in the control group (odds ratio control/intervention = 0.39, 95%CI = 0.17 to 0.92, P = 0.031).

CONCLUSION

The study demonstrates that ASyMS can support the management of symptoms in patients with lung, breast and colorectal cancer receiving chemotherapy.

Denitrification potential and rates of complex carbon source from dairy effluents in activated sludge system

A predictive model for the denitrification performance of complex carbon sources was proposed based on compositional data. Potential and rates of denitrification of single dairy components (lactose, lactate, proteins, fat), as well as binary and complex (modelled "process water") mixtures were assessed using test for nitrogen uptake rate (NUR). In all experiments, denitrification potential of mixtures was found to be significantly higher than the sum of individual potentials and denitrification rate with the readily biodegradable moiety of the mixtures was similar to the highest rate obtained with individual components (lactose or lactate). This work shows that activated sludge acclimated to dairy components can be modelled as a single biomass where the maximal anoxic growth rate of the biomass limits the denitrification rate with dairy components. As a consequence, lactose or lactate determine the maximal denitrification rate possible using dairy effluents.

Utilising handheld computers to monitor and support patients receiving chemotherapy: results of a UK-based feasibility study

GOALS OF WORK

Recent changes in cancer service provision mean that many patients spend a limited time in hospital and therefore experience and must cope with and manage treatment-related side effects at home. Information technology can provide innovative solutions in promoting patient care through information provision, enhancing communication, monitoring treatment-related side effects and promoting self-care.

PATIENTS AND METHODS

The aim of this feasibility study was to evaluate the acceptability of using handheld computers as a symptom assessment and management tool for patients receiving chemotherapy for cancer. A convenience sample of patients (n = 18) and health professionals (n = 9) at one Scottish cancer centre was recruited. Patients used the handheld computer to record and send daily symptom reports to the cancer centre and receive instant, tailored symptom management advice during two treatment cycles. Both patients' and health professionals' perceptions of the handheld computer system were evaluated at baseline and at the end of the project.

MAIN RESULTS

Patients believed the handheld computer had improved their symptom management and felt comfortable in using it. The health professionals also found the handheld computer to be helpful in assessing and managing patients' symptoms.

CONCLUSIONS

This project suggests that a handheld-computer-based symptom management tool is feasible and acceptable to both patients and health professionals in complementing the care of patients receiving chemotherapy.

Cerebral melioidosis

Two cases of cerebral melioidosis are presented to illustrate the clinical presentation and progress and to highlight the radiological features.

Isolated spinal cord lipoma

A case of isolated intradural spinal cord lipoma is presented. Most isolated spinal cord lipomas are intradural extramedullary, and the most common location is subpial. True intramedullary lipomas are very rare. Patient history is usually of months to years of local back pain, with recent escalation of pain and development of neurological symptoms. MRI examination shows a well circumscribed lesion of high signal on both T1 and T2 weighted images, and suppression on fat saturation sequence. Subtotal resection is the surgical aim. This improves pain but neurological symptoms rarely improve, usually are unchanged, and occasionally are worse.

[Symptoms reported by mobile cellular telephone users]

A survey study, using questionnaire, was conducted in 161 students and workers in a French engineering school on symptoms experienced during use of digital cellular phones. A significant increase in concentration difficulty (p < 0.05) was reported by users of 1800-MHz (DCS) cellular phones compared to 900-MHz (GSM) phone users. In users of cellular phones, women significantly (p < 0.05) complained more often of sleep disturbance than men. This sex difference for sleep complaint is not observed between women and men non-users of cellular phone. The use of both cellular phones and VDT significantly (p < 0.05) increased concentration difficulty. Digital cellular phone users also significantly (p < 0.05) more often complained of discomfort, warmth, and picking on the ear during phone conversation in relation with calling duration per day and number of calls per day. The complaint of warmth on the ear might be a signal to users for stopping the call.

Nonredundant roles of the mPer1 and mPer2 genes in the mammalian circadian clock

Mice carrying a null mutation in the Period 1 (mPer1) gene were generated using embryonic stem cell technology. Homozygous mPer1 mutants display a shorter circadian period with reduced precision and stability. Mice deficient in both mPer1 and mPer2 do not express circadian rhythms. While mPER2 regulates clock gene expression at the transcriptional level, mPER1 is dispensable for the rhythmic RNA expression of mPer1 and mPer2 and may instead regulate mPER2 at a posttranscriptional level. Studies of clock-controlled genes (CCGs) reveal a complex pattern of regulation by mPER1 and mPER2, suggesting independent controls by the two proteins over some output pathways. Genes encoding key enzymes in heme biosynthesis are under circadian control and are regulated by mPER1 and mPER2. Together, our studies show that mPER1 and mPER2 have distinct and complementary roles in the mouse clock mechanism.

The inter-sonographer reliability of carotid duplex ultrasound

Carotid duplex ultrasound (CDUS) is a non-invasive technique used to assess the severity of carotid artery stenosis. It has been shown to have good correlation with digital subtraction angiography (DSA) but has been criticised for its variability. One source of this is the variation in results between studies responsible for re-validating velocity criteria to match the established treatment thresholds of internal carotid artery (ICA) stenosis. The aim of this study was to develop velocity criteria and determine the presence of inter-sonographer variation of CDUS when grading ICA stenosis in our department. Five sonographers measured the degree of ICA stenosis with CDUS in 33 patients who also underwent DSA. Receiver operator characteristic curve analysis was used to develop optimal velocity criteria for the 50%, 70% and 90% ICA stenosis thresholds as a group and for each individual sonographer. A peak systolic velocity ratio of > or = 3.25 was shown to have the highest accuracy (91.5%) for predicting a 70% stenosis. A moderate value of kappa (0.53 +/- 0.027) was calculated if the optimum velocity criterion was employed for each sonographer. There was no significant variation between the ability of sonographers to grade ICA stenosis (P > 0.05) and an excellent ICC of 0.911 was calculated. This study provides evidence to suggest that CDUS in our department is not an operator-dependant test for the investigation of ICA stenosis.

Rhombencephalosynapsis

A case report of rhombencephalosynapsis in a 34-year-old female is presented and the clinical features and possible pathogenesis of this disorder are reviewed.

Engineering mouse chromosomes with Cre-loxP: range, efficiency, and somatic applications

Chromosomal rearrangements are important resources for genetic studies. Recently, a Cre-loxP-based method to introduce defined chromosomal rearrangements (deletions, duplications, and inversions) into the mouse genome (chromosome engineering) has been established. To explore the limits of this technology systematically, we have evaluated this strategy on mouse chromosome 11. Although the efficiency of Cre-loxP-mediated recombination decreases with increasing genetic distance when the two endpoints are on the same chromosome, the efficiency is not limiting even when the genetic distance is maximized. Rearrangements encompassing up to three quarters of chromosome 11 have been constructed in mouse embryonic stem (ES) cells. While larger deletions may lead to ES cell lethality, smaller deletions can be produced very efficiently both in ES cells and in vivo in a tissue- or cell-type-specific manner. We conclude that any chromosomal rearrangement can be made in ES cells with the Cre-loxP strategy provided that it does not affect cell viability. In vivo chromosome engineering can be potentially used to achieve somatic losses of heterozygosity in creating mouse models of human cancers.

Engineering a mouse balancer chromosome

Balancer chromosomes are genetic reagents that are used in Drosophila melanogaster for stock maintenance and mutagenesis screens. Despite their utility, balancer chromosomes are rarely used in mice because they are difficult to generate using conventional methods. Here we describe the engineering of a mouse balancer chromosome with the Cre-loxP recombination system. The chromosome features a 24-centiMorgan (cM) inversion between Trp53 (also known as p53) and Wnt3 on mouse chromosome 11 that is recessive lethal and dominantly marked with a K14-Agouti transgene. When allelic to a wild-type chromosome, the inversion suppresses crossing over in the inversion interval, accompanied by elevated recombination in the flanking regions. The inversion functions as a balancer chromosome because it can be used to maintain a lethal mutation in the inversion interval as a self-sustaining trans-heterozygous stock. This strategy can be used to generate similar genetic reagents throughout the mouse genome. Engineering of visibly marked inversions and deficiencies is an important step toward functional analyses of the mouse genome and will facilitate large-scale mutagenesis programs.

The mPer2 gene encodes a functional component of the mammalian circadian clock

Circadian rhythms are driven by endogenous biological clocks that regulate many biochemical, physiological and behavioural processes in a wide range of life forms. In mammals, there is a master circadian clock in the suprachiasmatic nucleus of the anterior hypothalamus. Three putative mammalian homologues (mPer1, mPer2 and mPer3) of the Drosophila circadian clock gene period (per) have been identified. The mPer genes share a conserved PAS domain (a dimerization domain found in Per, Arnt and Sim) and show a circadian expression pattern in the suprachiasmatic nucleus. To assess the in vivo function of mPer2, we generated and characterized a deletion mutation in the PAS domain of the mouse mPer2 gene. Here we show that mice homozygous for this mutation display a shorter circadian period followed by a loss of circadian rhythmicity in constant darkness. The mutation also diminishes the oscillating expression of both mPer1 and mPer2 in the suprachiasmatic nucleus, indicating that mPer2 may regulate mPer1 in vivo. These data provide evidence that an mPer gene functions in the circadian clock, and define mPer2 as a component of the mammalian circadian oscillator.

Telomerase expression in human somatic cells does not induce changes associated with a transformed phenotype

Expression of the human telomerase catalytic component, hTERT, in normal human somatic cells can reconstitute telomerase activity and extend their replicative lifespan. We report here that at twice the normal number of population doublings, telomerase-expressing human skin fibroblasts (BJ-hTERT) and retinal pigment epithelial cells (RPE-hTERT) retain normal growth control in response to serum deprivation, high cell density, G1 or G2 phase blockers and spindle inhibitors. In addition, we observed no cell growth in soft agar and detected no tumour formation in vivo. Thus, we find that telomerase expression in normal cells does not appear to induce changes associated with a malignant phenotype.

Improving staffing with a resource management plan

To change from a crisis to a proactive mode for staffing, scheduling, resource pool utilization, information management, and unit workload, nursing leaders developed a resource management plan. Changes that assisted in achieving that goal included: revision of department scheduling guidelines, elimination of day shift central supervisor, responsibility for daily staffing moved to unit-based managers, creation of a staffing model for the nursing resource pool staff, establishment of ideal complement of positions for every unit, expectation for unit to meet its staffing model every shift, reinforced department efforts to fill vacant positions, participation in computerized databases to study the use of resources, and identified critical staffing indicators for each unit.

Flashlamp pulsed dye laser (585 nm). Treatment of resistant verrucae

The treatment of recalcitrant plantar verrucae has represented challenging clinical problems for podiatric physicians. A procedure described by Borovoy et al studying 46 patients initially indicated a success rate of 76.1%. A review of 200 patients who have been treated with refined treatment protocols and modalities is presented, with an overall success rate of 79.9%. The Candella SPTL 1 and 1B have been used in the study. These lasers produce a full 450-microsecond pulse at 585 nm wave length. Hand pieces ranging from 2 mm to 7 mm were used. The energy density (fluence) used ranged from 6 to 9 J/cm2. Discussion will be presented including treatment protocol, modalities, comparisons with other forms of treatment, and overall success rates.

Feasibility of 'day case' laparoscopic cholecystectomy

Laparoscopic cholecystectomy was offered as a day case to 15 patients (mean age 42; range 33-72 years). Three patients required overnight admission for non-operative reasons. The mean in-hospital stay for those patients successfully treated as day cases was 8.5 h and overall 12 h (range 6-28 h). In selected cases day case laparoscopic cholecystectomy is a feasible alternative to conventional inpatient management.

Development of a somatic cell hybrid mapping panel and molecular probes for human chromosome 3

A somatic cell hybrid mapping panel and molecular probes have been developed for human chromosome 3. This panel defines 11 regions for the short and long arms of the chromosome. Four hundred thirty-two probes have been mapped using these hybrids. One hundred thirty-one of these probes were derived from EcoRI and HindIII flow-sorted libraries. The remaining 301 probes were isolated from NotI boundary and random (partial MboI) libraries constructed from a hybrid that provided a relative enrichment in 3p DNA sequences. For some regions of the chromosome, significant differences in the distribution of probes were noted. This was observed for both the unique sequence flow-sorted and NotI probes. These differences are in agreement with previous suggestions that Giemsa light bands are GC-rich, and therefore gene-rich (especially housekeeping genes), and that the Giemsa dark bands may contain DNA that is more highly condensed. The isolation of probes from different types of libraries, or by different screening strategies, appears to reduce deficiencies that might arise from the use of probes derived with a more limited approach. These hybrids and probes should facilitate the construction of physical and genetic linkage maps to identify various disease loci involving chromosome 3.

Thyroid lymphoma

We have reviewed the local experience of 15 cases of thyroid lymphoma with a view to documenting the epidemiology, presentation, management and prognostic factors governing outcome for this rare condition. All the patients were European despite the fact that 15 per cent of the local population is either Maori or Polynesian. The average age at presentation was 62 years and 13 of the 15 patients were women. The duration of symptoms was short: on average 9 months. Where feasible a definitive resection of the lesion was performed but this could only be performed in six of the 15 cases. The commonest histological type was non-Hodgkin's lymphoma which accounted for 14 of the 15 cases with the large cell variant being the most common (five cases). The mean period of follow-up was 3.3 years: only eight patients were alive and well at that time. The prognostic factors that influenced outcome were: (1) the histology of the lesion - large cell lymphoma carried a bad outlook; (2) whether the lesion could be totally resected or not - five out of six patients undergoing total resection remain alive and well; (3) the presence of pre-existing Hashimoto's thyroiditis was a favourable prognostic factor as only one patient without underlying Hashimoto's disease or positive antithyroid antibodies was alive at the end of the study; (4) male sex may also be an unfavourable prognostic factor as both men in the study died of disease 0.3 and 5 years after diagnosis.

Regional and physical mapping studies characterizing the Greig polysyndactyly 3;7 chromosome translocation, t(3;7)(p21.1;p13)

The Greig polysyndactyly-craniofacial anomalies syndrome is an autosomal dominant disorder involving a gene(s) located in band 7p13. We have isolated and characterized a reciprocal 3;7 chromosome translocation that resulted in the syndrome. We have identified two closely linked (0 cM) conserved DNA sequences (P137/p944B) that flank the translocation breakpoint. A pulsed-filed analysis combined with available genetic linkage information demonstrates that the disorder is linked (2 cM) to the T-gamma receptor locus, lending considerable support to the hypothesis that the mouse mutant extra-toes is the counterpart of the Greig syndrome. We have found no evidence that physically links the EGF receptor to the P137/p944B region, again compatible with mouse linkage relationships. The isolation of the der(3) chromosome from the 3;7 translocation has allowed us to regionally localize probes within the 3p21.1 band. For three probes commonly used in heterozygosity experiments with human cancers involving chromosome 3, we have determined that the order from centromere to telomere is D3S3, D3S2, and DNF15S2. Our pulsed-field studies also demonstrate the utility of band density differences combined with partial digests in evaluating linkage relationships. The P137/p944B probes should be useful in examining other hereditary disorders with phenotypic similarities to the Greig syndrome.

[Pheochromocytomas: diagnosis, anesthesia and treatment. Apropos of 17 recent cases]

This article summarizes 5 years of systematic observation of 17 patients presenting with benign pheochromocytoma. The diagnosis was based on clinical and biological findings which were consistently positive. The topographical diagnosis was based on CT scans, and a combination of intravenous urograms and nephrotomography. The preoperative preparations were made with labetalol, and the anesthetic used was narconeuroleptanalgesic. The hemodynamic study was carried out with a Swann-Ganz catheter, which proved indispensable in the surveillance of the patient at operation. The surgical procedure is best performed with transperitoneal subcostal incisions, which the authors prefer. Morbidity was negligible, and mortality, zero.

[Malignant adrenal cortex tumors responsible for primary hyperaldosteronism and biological hypercorticism. Remarks apropos of 2 surgically-treated cases]

Two cases of malignant adrenal cortex tumors revealed by primary hyperaldosteronism with hypertension, and associated with a biological hypercortisonism, are reported. Diagnosis of this very rare affection depends on the finding of marked biological hyperaldosteronism associated with a large adrenal tumor. The outcome appears to be rapidly fatal for tumors exceeding 5 cm in diameter and associated with lymph node invasion. This raises the problem of the utility of surgery in these cases, operative intervention apparently accelerating progression of the lesion. In practice, however, a laparotomy is always justifiable, the most rational biopsy being excision of the tumor.

Case report. Malignant change in an intracranial epidermoid cyst

A malignant epidermoid tumor invading the fourth ventricle had histologic features that indicated malignant transformation in a benign epidermoid cyst. The computed tomographic (CT) findings correlated precisely with the histologic features, revealing both pathologic enhancement and a low attenuation zone. The spectrum of described CT findings in intracranial epidermoids is reviewed and contrasted with the appearance encountered in the present case.

Rapid serial cranial computed tomography for tumor diagnosis

Rapid serial computed tomography (RSCT) provides more information about the cerebral cortical capillary bed and leptomeningeal vessels than conventional enhanced computed tomography (CT). This increased neuroanatomical definition has potential value for separating intra- from extracerebral tumors in selected cases. RSCT offers better visualization of the angioarchitecture of highly vascular tumors than conventional enhanced CT. However, CT scans delayed several minutes after contrast administration are more useful for evaluating the extent of hypovascular tumors. Time-density curves were of limited value for tumor evaluation. However, the peak increase of Hounsfield units did correlate well with the degree of tumor vascularity assessed angiographically.