Financial impact of incorporating deep learning reconstruction into magnetic resonance imaging routine

PURPOSE

Artificial intelligence and deep learning solutions are increasingly utilized in healthcare and radiology. The number of studies addressing their enhancement of productivity and monetary impact is, however, still limited. Our hospital has faced a need to enhance MRI scanner throughput, and we investigate the utility of new commercial deep learning reconstruction (DLR) algorithm for this purpose. In this work, a multidisciplinary team evaluated the impact of the widespread deployment of a new commercial deep learning reconstruction (DLR) algorithm for our magnetic resonance imaging scanner fleet.

METHODS

Our analysis centers on the DLR algorithm's effects on patient throughput and investment costs, contrasting these with alternative strategies for capacity expansion-namely, acquiring additional MRI scanners and increasing device utilization on weekends. We provide a framework for assessing the financial implications of new technologies in a trial phase, aiding in informed decision-making for healthcare investments.

RESULTS

We demonstrate substantial reductions in total operating costs compared to other capacity-enhancing methods. Specifically, the cost of adopting the deep learning technology for our entire scanner fleet is only 11 % compared to procuring an additional scanner and 20 % compared to the weekend utilization costs of existing devices.

CONCLUSIONS

Procuring DLR for our existing five-scanner fleet allows us to sustain our current MRI service levels without the need for an additional scanner, thereby achieving considerable cost savings. These reductions highlight the efficiency and economic viability of DLR in optimizing MRI service delivery.

Increased mortality after post-stroke epilepsy following primary intracerebral hemorrhage

OBJECTIVES

This study aimed to determine whether post-stroke epilepsy (PSE) predicts mortality, and to describe the most prominent causes of death (COD) in a long-term follow-up after primary intracerebral hemorrhage (ICH).

METHODS

We followed 3-month survivors of a population-based cohort of primary ICH patients in Northern Ostrobothnia, Finland, for a median of 8.8 years. Mortality and CODs were compared between those who developed PSE and those who did not. PSE was defined according to the ILAE guidelines. CODs were extracted from death certificates (Statistics Finland).

RESULTS

Of 961 patients, 611 survived for 3 months. 409 (66.9%) had died by the end of the follow-up. Pneumonia was the only COD that was significantly more common among the patients with PSE (56% vs. 37% of deaths). In the multivariable models, PSE (hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.06-1.87), age (HR 1.07, 95% CI 1.06-1.08), male sex (HR 1.35, 95% CI 1.09-1.67), dependency at 3 months (HR 1.52, 95% CI 1.24-1.88), non-subcortical ICH location (subcortical location HR 0.78, 95% CI 0.61-0.99), diabetes (HR 1.43, 95% CI 1.07-1.90) and cancer (HR 1.45, 95% CI 1.06-1.98) predicted death in the long-term follow-up.

CONCLUSION

PSE independently predicted higher late morality of ICH in our cohort. Pneumonia-related deaths were more common among the patients with PSE.

Early vs. late enoxaparin for the prevention of venous thromboembolism in patients with ICH: A double blind placebo controlled multicenter study

BACKROUND

Venous thromboembolism (VTE) after primary intracerebral hemorrhage (ICH) worsens patient prognosis. Administering low-molecular weight heparins (LMWH) to prevent VTE early (24 h) may increase the risk of hematoma enlargement, whereas administering late (72 h) after onset may decrease its effect on VTE prevention. The authors investigated when it is safe and effective to start LMWH in ICH patients.

METHODS

In the setting of double blinded, placebo controlled randomization, patients >18 years of age with paretic lower extremity, and admitted to the emergency room within 12 h of the onset of ICH, were randomized into two groups. Patients in the enoxaparin group received 20 mg twice a day 24 h (early) after the onset of ICH and in the placebo group 72 h (late) after onset respectively. Both groups immediately received intermittent pneumatic compression stockings at the ER. Patients were prospectively and routinely screened for VTE and hemorrhagic complications 1 day after entering the study and again before discharge.

RESULTS

139 patients were included for randomization in this study. Only 3 patients developed VTE, 2 in the early enoxaparin group and one in the late enoxaparin group. No patients developed PE. Thromboembolic events (p = 0.901), risk of hematoma enlargement (p = 0.927) and overall outcome (P = 0.904) did not differ significantly between the groups.

CONCLUSION

Administering 40 mg/d LMWH for prevention of VTE to a spontaneous ICH patient is safe regardless of whether it is started 24 h (early) or 72 h (late) after the hemorrhage. Risk of hemorrhage enlargement is not associated with early LMWH treatment. Administering LMWH late did not increase VTEs.

Poststroke epilepsy in long-term survivors of primary intracerebral hemorrhage

OBJECTIVE

To identify the incidence and predisposing factors for development of poststroke epilepsy (PSE) after primary intracerebral hemorrhage (PICH) during a long-term follow-up.

METHODS

We performed a retrospective study of patients who had had their first-ever PICH between January 1993 and January 2008 in Northern Ostrobothnia, Finland, and who survived for at least 3 months. These patients were followed up for PSE. The associations between PSE occurrence and sex, age, Glasgow Coma Scale (GCS) score on admission, hematoma location and volume, early seizures, and other possible risk factors for PSE were assessed using the Cox proportional hazards regression model.

RESULTS

Of the 615 PICH patients who survived for longer than 3 months, 83 (13.5%) developed PSE. The risk of new-onset PSE was highest during the first year after PICH with cumulative incidence of 6.8%. In univariable analysis, the risk factors for PSE were early seizures, subcortical hematoma location, larger hematoma volume, hematoma evacuation, and a lower GCS score on admission, whereas patients with infratentorial hematoma location or hypertension were less likely to develop PSE (all variables p < 0.05). In multivariable analysis, we found subcortical location (hazard ratio [HR] 2.27, 95% confidence interval [CI] 1.35-3.81, p < 0.01) and early seizures (HR 3.63, 95% CI 1.99-6.64, p < 0.01) to be independent risk factors, but patients with hypertension had a lower risk of PSE (HR 0.54, 0.35-0.84, p < 0.01).

CONCLUSIONS

Subcortical hematoma location and early seizures increased the risk of PSE after PICH in long-term survivors, while hypertension seemed to reduce the risk.

Isolated neurosarcoidosis – MR findings and pathologic correlation: A case report

Neurosarcoidosis is a diagnostic challenge, especially if systemic symptoms are absent. We present a 49-year-old woman with isolated neurosarcoidosis. The main symptom was loss of vision in the left eye. Brain MR imaging showed 6 high-signal white matter lesions frontotemporally on proton density and T2-weighted turbo spin-echo images. Coronal fat-saturated turbo FLAIR images of the orbits showed a swollen left optic nerve with increased signal intensity, which finding has not been previously published in sarcoid optic neuropathy. A control MR examination showed meningeal enhancement of the left optic nerve and leptomeningeal enhancing lesions around the brain stem. Spinal MR revealed leptomeningeal enhancement throughout the spinal cord and asymptomatic enhancing cauda equina lesions, mimicking subarachnoid tumour seeding, and an enhancing nerve root mass at Th12/L1. Biopsy of the latter lesion revealed non-caseating granulomas consistent with sarcoidosis.

DTI abnormalities in adults with past history of attention deficit hyperactivity disorder: a tract-based spatial statistics study

BACKGROUND

Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique enabling visualization and measurement of white matter tracts. Attention deficit hyperactivity disorder (ADHD) has been studied with DTI earlier with variable results, yet there is little research on remitted ADHD.

PURPOSE

To compare the brain white matter between ADHD drug naïve subjects whose ADHD symptoms have mostly subsided and healthy controls.

MATERIAL AND METHODS

Tract-based spatial statistics (TBSS) was used to compare 30 subjects with adolescent ADHD with control subjects at the age of 22-23 years. The study population was derived from a population-based Northern Finland Birth Cohort 1986. Fractional anisotropy (FA), mean diffusivity (MD), and measures of diffusion direction (λ1-3) were calculated. Permutation testing was used to test for differences in mean values of FA, MD, and λ1-3 between the groups. The results were corrected for multiple comparisons across the whole white matter skeleton.

RESULTS

The ADHD group showed increased FA related to decreased radial diffusivity in the left forceps minor (P < 0.05). In the vicinity along the same tract, axial diffusion was significantly decreased without any significant effect on FA. No between-group difference in MD was observed. Regressor analysis revealed no gender-, IQ- or GAF-related changes. After removal of left handed subjects the statistical significance was only barely lost.

CONCLUSION

In a setting with remitted ADHD, the results may represent a compensatory mechanism in the left forceps minor.

Predictive value of C-reactive protein for the outcome after primary intracerebral hemorrhage

OBJECT

Primary intracerebral hemorrhage (ICH) carries high morbidity and mortality rates. Several factors have been suggested as predicting the outcome. The value of C-reactive protein (CRP) levels in predicting a poor outcome is unclear, and findings have been contradictory. In their population-based cohort, the authors tested whether, independent of confounding factors, elevated CRP levels on admission (< 24 hours after ictus) are associated with an unfavorable outcome.

METHODS

The authors identified all patients who suffered primary ICH between 1993 and 2008 among the population of Northern Ostrobothnia, Finland, and from the laboratory records they extracted the CRP values at admission. Independent predictors of an unfavorable outcome (moderate disability or worse according to the Glasgow Outcome Scale at 3 months) were tested by unconditional logistic regression in a model including all the well-established confounding factors and CRP on admission.

RESULTS

Of 961 patients, 807 (84%) had CRP values available within 24 hours of admission, and multivariable analysis showed elevated CRP at that point to be associated with an unfavorable outcome (OR 1.41 per 10 mg/L [95% CI 1.09-1.81], p < 0.01), together with diabetes mellitus (OR 1.99 [95% CI 1.09-3.64], p < 0.05), age (1.06 per year [95% CI 1.04-1.08], p < 0.001), low Glasgow Coma Scale score (0.75 per unit [95% CI 0.67-0.84], p < 0.001), hematoma size (1.05 per ml [95% CI 1.03-1.07], p < 0.001), and the presence of an intraventricular hemorrhage (2.70 [95% CI 1.66-4.38], p < 0.001). Subcortical location predicted a favorable outcome (0.33 [95% CI 0.20-0.54], p < 0.001).

CONCLUSIONS

Elevated CRP on admission is an independent predictor of an unfavorable outcome and is only slightly associated with the clinical and radiological severity of the bleeding.

Association between warfarin combined with serotonin-modulating antidepressants and increased case fatality in primary intracerebral hemorrhage: a population-based study

Object

Patients receiving oral anticoagulants run a higher risk of cerebral hemorrhage with a poor outcome. Serotonin-modulating antidepressants (selective serotonin reuptake inhibitors [SSRIs], serotonin-norepinephrine reuptake inhibitors [SNRIs]) are frequently used in combination with warfarin, but it is unclear whether this combination of drugs influences outcome after primary intracerebral hemorrhage (PICH). The authors investigated case fatality in PICH among patients from a defined population who were receiving warfarin alone, with aspirin, or with serotonin-modulating antidepressants.

Methods

Nine hundred eighty-two subjects with PICH were derived from the population of Northern Ostrobothnia, Finland, for the years 1993–2008, and those with warfarin-associated PICH were eligible for analysis. Their hospital records were reviewed, and medication data were obtained from the national register of prescribed medicines. Kaplan-Meier survival curves were drawn to illustrate cumulative case fatality, and a Cox proportional-hazards analysis was performed to demonstrate predictors of death.

Results

Of the 176 patients eligible for analysis, 17 had been taking aspirin and 19 had been taking SSRI/SNRI together with warfarin. The 30-day case fatality rates were 50.7%, 58.8%, and 78.9%, respectively, for those taking warfarin alone, with aspirin, or with SSRI/SNRI (p = 0.033, warfarin plus SSRI/SNRI compared with warfarin alone). Warfarin combined with SSRI/SNRI was a significant independent predictor of case fatality (adjusted HR 2.10, 95% CI 1.13–3.92, p = 0.019).

Conclusions

Concurrent use of warfarin and a serotonin-modulating antidepressant, relative to warfarin alone, seemed to increase the case fatality rate for PICH. This finding should be taken into account if hematoma evacuation is planned.

[Gliomatosis cerebri as cause of neuropsychiatric symptoms]

Gliomatosis cerebri (GC) is a rare cancer of the central nervous system, having already penetrated into various areas of the central nervous system upon becoming manifest. In tissue specimens the histopathologic picture of the tumor appears similar to that seen in diffuse gliomas at different stages of disease. Typical MRI findings in GC include diffuse increases in signal intensity in the brain, and indistinct gray-white matter demarcation in T2-weighted images. Surgical treatment is usually not possible. We describe a patient, in whom CG turned eventually out to be the cause of severe neuropsychiatric symptoms.

Clinical Characteristics of C9ORF72-Linked Frontotemporal Lobar Degeneration

BACKGROUND

The most common genetic cause of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) has been linked to a hexanucleotide repeat expansion in the C9ORF72 gene. The frequency of the C9ORF72 expansion in Finland is among the highest in the world.

METHODS

We assessed 73 Finnish patients with FTLD in order to examine the clinical characteristics associated with the expanded C9ORF72. Demographic and clinical features were evaluated. As a potential disease modifier, the apolipoprotein E (APOE) genotype was also assessed. Neuropathological analysis was available on 2 expansion carriers and 1 non-carrier.

RESULTS

The C9ORF72 expansion was present in 20 of 70 (29%) probands. Significant associations with the C9ORF72 expansion were observed for concomitant ALS and positive family history of dementia or ALS. Psychoses were detected in both carriers and non-carriers (21 vs. 10%, p = 0.25). The APOE ε4 allele did not cluster among expansion carriers. Numerous p62-positive neuronal inclusions were detected in the cerebellar cortex of the 2 expansion carriers.

CONCLUSION

In line with the suggested C9ORF72 core phenotype, we also detected a high frequency of neuropsychiatric symptoms; however, these symptoms seem not be specific to C9ORF72-associated FTLD. FTLD should be considered in cases of middle-age-onset psychosis.

Predictors for recurrent primary intracerebral hemorrhage: a retrospective population-based study

BACKGROUND AND PURPOSE

Underlying comorbidities, previous strokes, and medication may increase the risk for primary intracerebral hemorrhage (PICH) and its recurrence. The aim of this study was to determine the independent predictors for recurrent PICH.

METHODS

We identified 961 subjects with first-ever PICH from 1993 to 2008 among the population of Northern Ostrobothnia, Finland. Hospital and death records were reviewed and data on drug use were obtained from the national register of prescribed medicines. Kaplan-Meier survival curves and Cox proportional hazards models were used to demonstrate predictors for recurrence of PICH.

RESULTS

Total follow-up time of the 961 patients was 3481 person-years. During the follow-up time, 58 subjects had altogether 68 recurrent PICHs. The annual average incidence of first recurrence was 1.67%. Cumulative 5- and 10-year incidence rates were 9.6% and 14.2%, respectively. In univariable analysis, history of ischemic stroke, diabetes mellitus, and aspirin use were associated with a higher recurrence rate. In multivariable analysis, only previous ischemic stroke (adjusted hazard ratio, 2.22; 95% confidence interval, 1.22-4.05; P=0.009) independently predicted PICH recurrence. Diabetes mellitus tended to increase (adjusted hazard ratio, 2.38; 95% confidence interval, 0.98-5.80; P=0.056), whereas treated hypertension tended to decrease (0.45, 0.20-1.01; P=0.054) the risk for fatal recurrent PICH.

CONCLUSIONS

Previous ischemic stroke independent of confounding factors may increase the risk for PICH recurrence.

Improved survival of patients with warfarin-associated intracerebral haemorrhage: a retrospective longitudinal population-based study

BACKGROUND

Warfarin-associated intracerebral haemorrhage carries poor outcome due to rapid haemorrhage growth. Reversal of warfarin anticoagulation with prothrombin complex concentrate has been implemented as an acute treatment option for these subjects.

AIM

We investigated whether survival of subjects with warfarin-associated intracerebral haemorrhage had improved after implementation of reversal of warfarin anticoagulation with prothrombin complex concentrate.

METHODS

We identified all subjects with warfarin-associated intracerebral haemorrhage during 1993-2008 among the population of Northern Ostrobothnia, Finland. From 2004 onwards, prothrombin complex concentrate was used in Oulu University Hospital, the only hospital treating intracerebral haemorrhage subjects in the region, to counteract the effect of warfarin in subjects with warfarin-associated intracerebral haemorrhage. We compared the outcomes of subjects admitted during 1993-2003 and 2004-2008 and those treated and not treated with prothrombin complex concentrate. We also explored the predictors for one-year survival of the warfarin-associated intracerebral haemorrhage subjects.

RESULTS

We identified altogether 181 subjects who had intracerebral haemorrhage while on warfarin. One-year survival was significantly (P = 0·031) higher for the 60 subjects admitted during 2004-2008 (43·3%) than for the 121 admitted before 2004 (30·6%). In multivariable analysis, prothrombin complex concentrate treatment reduced one-year case fatality (hazard ratio 0·52, 95% confidence interval 0·29-0·93). Thromboembolic complications did not occur more frequently among those treated with prothrombin complex concentrate.

CONCLUSION

The survival of warfarin-associated intracerebral haemorrhage subjects among the population of Northern Ostrobothnia has improved likely because of introduction of prothrombin complex concentrate.

White matter in autism spectrum disorders - evidence of impaired fiber formation

BACKGROUND

Diffusion tensor imaging (DTI) enables measurements and visualization of the microstructure of neural fiber tracts. The existing literature on autism spectrum disorders (ASDs) and DTI is heterogenous both regarding methodology and results.

PURPOSE

To compare brain white matter of high-functioning individuals with ASDs and controls.

MATERIAL AND METHODS

Tract-based spatial statistics (TBSS), a voxel-based approach to DTI, was used to compare 27 subjects with ASDs (mean age 14.7 years, range 11.4-17.6 years, 20 boys, 7 girls) and 26 control subjects (mean age 14.5 years, range 11.7-17.3 years, 17 boys, 9 girls). Mean fractional anisotropy (FA) image (skeleton) was created and each subject's aligned FA data were then projected onto this skeleton. Voxelwise cross-subject statistics on the skeletonized FA data, mean diffusivity (MD), and measures of diffusion direction were calculated. Importantly, the data were corrected across the whole image instead of using ROI-based methods.

RESULTS

The ASD group showed significantly greater FA (P < 0.05, corrected) in the area containing clusters of optic radiation and the right inferior fronto-occipital fasciculus (iFOF). In the same area, λ(3) (representing transverse diffusion) was significantly reduced in the ASD group. No age-related changes were found.

CONCLUSION

The results suggest that the reduced transverse diffusion within the iFOF is related to abnormal information flow between the insular salience processing areas and occipital visual areas.

Imaging findings and accuracy of core needle biopsy in mucinous carcinoma of the breast

BACKGROUND

Diagnosis of mucinous carcinoma can be difficult due to its benign appearance on mammograms and ultrasonographic (US) images. In the light of the rather scarce literature, core needle biopsy (CNB) has proved useful in diagnosing mucinous lesions.

PURPOSE

To assess mammographic, US, and CNB findings of mucinous breast tumors and to correlate them with final histology obtained in therapeutic surgery.

MATERIAL AND METHODS

From 2000-2006, 25 mucinous carcinomas detected with CNB were surgically removed. The mammography, US, and CNB results were analyzed and correlated with final histology.

RESULTS

Ninety-six percent of the mucinous carcinomas (24/25) were visible with US. All except two of the 24 tumors were solid masses. All the mixed-type lesions (group 2) were hypoechoic and had irregular or lobulated margins and heterogeous internal echotexture. The US features were more variable among the 14 pure mucinous carcinomas (group 1) and the six US visible mucinous carcinomas with cancerous cells outside the tumor (group 3). Fifty-seven percent of group 1 and 50% of group 3 tumors had clearly lobulated or irregular margins. Fifty-seven percent of group 1 and 67% of group 3 cancers were hypoechoic. A vast majority of these tumors had heterogenous echotexture. Seventy-one percent (17/24) of the lesions visible with US had posterior acoustic enhancement. Eighty percent (20/25) of the mucinous carcinomas were classified as BI-RADS 4 lesions in US. All the lesions with images available were visible on mammograms, where most of the tumors were seen as a high-density circumscribed lesion and classified as BI-RADS 4 lesions, while none were classified as BI-RADS 1, 2 or 5. The sensitivity and positive predictive value of CNB regarding mucinous carcinoma was 100%.

CONCLUSION

CNB was found to be a highly reliable diagnostic tool for diagnosing mucinous carcinoma in this selected material. US findings of pure mucinous carcinoma were variable, however, all reached BI-RADS 4 category. The presence of posterior acoustic enhancement beneath a solid breast lesion should raise suspicion of mucinous carcinoma. Most of the tumors appeared as BI-RADS 4 lesions in US and in mammography thus making both a useful tool for raising a suspicion of malignancy in mucinous cancers.

[Microhemorrhages in the brain. A magnetic resonance imaging finding with emerging significance]

Microhemorrhages in the brain refer to minor chronic hemorrhages that are revealed by specific magnetic imaging techniques. Whereas microhemorrhages in the brain are a common finding in patients with a disorder of the cerebral circulation, they are surprisingly often found also in elderly persons who are considered healthy. Microhemorrhages can be regarded as a biomarker of cerebral microangiopathy. They may also offer additional diagnostic information, provide clues for the prognosis of brain diseases, and influence clinical decisions. The patient's medical history, the location, number and distribution of imaging findings have a central role in the assessment of clinical significance.

Ultrasonography and core needle biopsy in the differential diagnosis of fibroadenoma and tumor phyllodes

BACKGROUND

The diagnosis of phyllodes tumors of the breast is challenging due to many similarities with common fibroadenomas.

PURPOSE

To determine the diagnostic accuracy of core needle biopsy in diagnosing phyllodes tumors and to analyze the ultrasonographic (US) features of phyllodes tumors and fibroadenomas.

MATERIAL AND METHODS

From 1999 to 2003, 1010 breast lesions underwent imaging-guided core needle biopsy. Of these, 57 fibroadenomas and 12 phyllodes tumors were removed surgically. The US and needle biopsy results of a total of 64 lesions (52 fibroadenomas and 12 phyllodes tumors) were further analyzed, compared, and correlated with surgical histological results.

RESULTS

The median sonographic sizes of the phyllodes tumors and the fibroadenomas were 3.2 cm and 1.6 cm, respectively. At US, 58% of the phyllodes tumors (7/12) were classified as equivocal or suspicious of malignancy and 42% (5/12) as probably benign, while 54% of the fibroadenomas (28/52) were classified as probably benign and 46% (24/52) as equivocal. The sensitivity, specificity, and positive and negative predictive values of core needle biopsy histology regarding tumor phyllodes were 83%, 92%, 71%, and 96%, respectively.

CONCLUSION

Imaging-guided core needle biopsy was accurate in differentiating between fibroadenomas and phyllodes tumors. US classification was unreliable due to considerable overlap in the findings. Combined use of US feature analysis and needle biopsy may help to avoid the misinterpretation of phyllodes as fibroadenoma.

Potential of diffusion imaging in brain tumors: a review

Diffusion magnetic resonance imaging (MRI) is a method for quantifying the microscopic random motion of water molecules in tissues. Diffusion imaging provides indirect structural information of a kind not available on basic MRI sequences of many pathological conditions. Lately, especially brain tumors have been under active investigation, with numerous papers already published, and their number continues to increase. This review summarizes the heterogeneous and complex research data on diffusion imaging of brain tumors.

Intra-arterial chemotherapy with mitomycin C in gallbladder cancer: A follow-up study

BACKGROUND AND OBJECTIVES

There is only limited and somewhat controversial information available on hepatic artery infusion of cytotoxic agents in gallbladder cancer. We report the results of 5-year follow-up of all gallbladder cancer patients treated with surgery and intra-arterial mitomycin C or mitomycin C alone in our hospital during 15 years.

METHODS

Thirty-five patients with gallbladder cancer were treated with superselective intra-arterial chemotherapy (SIAC) with mitomycin C during 1981-1996. Survival was measured from diagnosis, and all patients were followed up until death or the end of January 2002. Cumulative survival rates and median survival times were calculated for all patients, according to response to treatment and staging. The data are presented as 5-year survival.

RESULTS

Median survival times after SIAC for all patients, responders, and non-responders were 48, 60+, and 8.5 months, respectively. Overall response rate was 60%. Survival was significantly better for tumors limited to the gallbladder wall, as expected. Drug toxicity occurred in half of the patients, requiring cessation of chemotherapy in 25% of the cases.

CONCLUSIONS

The median survival of gallbladder cancer patients treated with surgery and SIAC seems to be significantly better compared to the previously reported outcome of surgical treatment alone. Drug toxicity limits the use of i.a. chemotherapy and requires careful monitoring for early side-effects.

Pneumothorax and the value of chest radiography after ultrasound-guided thoracocentesis

PURPOSE

To determine the incidence, the operator's experience, and other variables that may influence the development of pneumothorax or re-expansion edema after ultrasound (US)-guided thoracocentesis.

MATERIAL AND METHODS

The medical records of 264 procedures in 212 patients who had undergone US-guided thoracocentesis in our radiology department or intensive care unit during the period 1996-2001 were retrospectively reviewed.

RESULTS

Post-thoracocentesis pneumothorax occurred in 11 cases, the incidence being 4.2% (11/264). None of the pneumothoraces occurred in the 10 mechanically ventilated patients. All but one patient with pneumothorax were asymptomatic or had only minor symptoms. Chest tube drainage was needed in one patient with a large pneumothorax. No re-expansion edema was recorded, although 1500 ml or more pleural fluid was aspirated in 29 patients. The operator's experience had no effect on the complication rate. Needle size was the only significant variable that contributed to the pneumothorax rate.

CONCLUSION

US-guided thoracocentesis can be done equally as safely by residents as by senior radiologists. The safety and feasibility of the method are evident among mechanically ventilated intensive care patients. Our results do not support the routine use of post-thoracocentesis chest radiography.

Lymphoma of the cervix. Imaging and transcatheter arterial embolization

A case of uterine cervix lymphoma with selective embolization after angiography is described. Chemotherapy and radiotherapy were carried out and surgery was avoided.

Lymphoma of the cervix. Imaging and transcatheter arterial embolization

A case of uterine cervix lymphoma with selective embolization after angiography is described. Chemotherapy and radiotherapy were carried out and surgery was avoided.

Increased amount of type III pN-collagen in AAA when compared with AOD

OBJECTIVE

the extent of the processing of type III procollagen to type III collagen was determined in nine human abdominal aortic aneurysms (AAA), and compared with ten samples of aortoiliac occlusive disease (AOD).

METHODS

the aminoterminal propeptide (PIIINP) and telopeptide (IIINTP) of type III procollagen and collagen, respectively, were immunologically measured in the soluble and insoluble fractions of the extracellular matrix. The assay for PIIINP in the insoluble matrix was further validated.

RESULTS

the insoluble matrices of AAAs contained at least 12 times more incompletely processed type III pN-collagen than AOD specimens (0.74% and 0.061%, respectively). Also, the soluble extracts of AAAs tended to contain more non-processed type III pN-collagen than free, properly cleaved aminoterminal propeptide.

CONCLUSIONS

the larger amount of type III pN-collagen suggests an alteration in the metabolism of type III collagen in AAAs. This may partially explain the decreased tensile strength of the aortic tissue.

Increased amount of type III pN-collagen in human abdominal aortic aneurysms: evidence for impaired type III collagen fibrillogenesis

PURPOSE

This study aimed to characterize the distribution of structural domains of type I and III collagens in the wall of abdominal aortic aneurysms (AAAs), by the use of undilated atherosclerotic aortas (aortoiliac occlusive disease [AOD]) and healthy abdominal aortas as controls.

METHODS

Immunohistochemical staining was applied with antibodies for the aminoterminal propeptides of type I (PINP) and type III (PIIINP) procollagens, which represent newly synthesized type I and III pN-collagens. In addition, an antibody against the aminoterminal telopeptide of type III collagen (IIINTP) was used as a means of detecting maturely cross-linked type III collagen fibrils.

RESULTS

The newly synthesized type III procollagen detected by means of PIIINP staining was concentrated in the media in aneurysmal aortas, whereas type I pN-collagen was localized in the intima in both AAAs and AODs. The healthy aortas showed no immunoreactivity for either PIIINP or PINP. The cross-linked type III collagen, detected by means of IIINTP staining, stained transmurally in all study groups, but appeared more abundant in the media in AAAs.

CONCLUSION

Our results strongly suggest that the metabolism of type III collagen is enhanced in AAAs. Intensive type III pN-collagen staining was present mainly in the media layer in AAAs, suggesting a role of type III collagen in aneurysm formation, whereas type I pN-collagen was present in the intima in both AAAs and AODs, suggesting that type I collagen synthesis is a fibroproliferative response related to the atherosclerotic process. The increased type III pN-collagen in AAAs may result in impaired fibril formation and, thus, in decreased tensile strength of aneurysmal tissue.

Type I and III collagens in human colon cancer and diverticulosis

BACKGROUND

Collagens are major proteins in the extracellular matrix, providing tissues with tensile strength. They are also important for cell adhesion and the invasion of malignant tumours.

METHODS

Thirty-nine samples of human colon (24 diverticulosis, 6 malignant tumours, 9 controls) were collected during elective surgery. Immunoassays for different domains of type I and III collagens and procollagens were used in soluble tissue extracts and trypsin digests of tissue samples.

RESULTS

The contents of cross-linked type I and III collagen telopeptides and total collagen were similar in diverticulosis and healthy tissue, whereas in malignant tissue maturely cross-linked type III collagen was scarce. Furthermore, some of the cross-linked type I telopeptide antigens were exceptionally small in size, indicating that the cross-linking of type I collagen in collagen fibres is impaired in cancer. The rate of type I collagen synthesis was clearly increased in malignancy, but not significantly in diverticulosis. However, type III collagen synthesis was increased in diverticulosis, but not in malignancy.

CONCLUSIONS

In colon malignancy, the collagen cross-linking process was aberrant and the synthesis of type I collagen increased. In diverticulosis, the synthesis of type III collagen was increased, suggesting only moderately increased metabolic activity.

Cross-linked telopeptides of type I and III collagens in malignant ovarian tumours in vivo

Malignant tumours often induce a fibroproliferative response in the adjacent stroma, characterized by increased expression of type I and type III procollagens. In normal tissues, fibrillar collagens normally undergo extensive intermolecular cross-linking that provides tensile strength to the tissue. Here we set out to characterize collagen cross-linking in human ovarian carcinoma tissue in vivo. Biochemical and immunochemical methods were used for cross-linked telopeptides of type I and III collagens in samples of benign and malignant serous tumours. The locations and staining patterns of these proteins were visualized immunohistochemically. The contents of both total collagen and the cross-linked type I and type III collagens in the malignant samples were only about 20% of those in the benign tumours. The cross-linked telopeptide antigens derived from the collagens were smaller and more heterogeneous in size in the malignant than in the benign tumours, indicating a defective cross-linking process scarcely leading to the formation of mature cross-links in the collagen fibres in malignancy. Immunostaining revealed disorganized type I and type III collagen bundles in carcinomas. These findings suggest that the collagen cross-linking process is aberrant in malignant tumours, possibly resulting in increased susceptibility of tumour collagens for the proteolysis often associated with tumour invasion.

Complete processing of type III collagen in atherosclerotic plaques

The extent of processing of type III collagen is assessed, and the proportions of type I and III collagens are estimated in atherosclerotic plaques obtained from the carotid artery, common femoral artery, and aorta. The fraction of type III collagen that had retained its amino-terminal propeptide (pN-collagen) was 42% in the soluble extract but only 0.0081% in the insoluble residue. Taken together, only 0.011% of the type III collagen in whole plaques was in the form of type III pN-collagen. Together with the small amounts of the free propeptides of type I procollagen, this finding indicates a low rate of collagen turnover. The amounts of solubilized telopeptides of type I and III collagens were measured, after heat denaturation and trypsin digestion of the collagenous helix, by specific immunoassays for the corresponding trypsin-generated antigens. The mean proportion of type III collagen was 61% (95% confidence interval, 58% to 65%) in the carotid and femoral artery plaques and 56% (95% confidence interval, 44% to 68%) in the aortic specimens. The completely processed and cross-linked type III collagen seems to be the major collagen type in atherosclerotic plaques.