Treatment of micropollutants in wastewater: Balancing effectiveness, costs and implications.

In this contribution, we analyse scenarios of advanced wastewater treatment for the removal of micropollutants. By this we refer to current mainstream, broad spectrum processes including ozonation and sorption onto activated carbon. We argue that advanced treatment requires properly implemented tertiary (nutrient removal) treatment in order to be effective. We review the critical aspects of the main advanced treatment options, their advantages and disadvantages. We propose a quantification of the costs of implementing advanced treatment, as well as upgrading plants from secondary to tertiary treatment when needed, and we illustrate what drives the costs of advanced treatment for a set of standard configurations. We propose a cost function to represent the total costs (investment, operation and maintenance) of advanced treatment. We quantify the implications of advanced treatment in terms of greenhouse gas emissions. Based on the indicators of total toxic discharge, toxicity at the discharge points and toxicity across the stream network discussed in Pistocchi et al. (2022), we compare costs and effectiveness of different scenarios of advanced treatment. In principle the total toxic load and toxicity at the points of discharge could be reduced by about 75 % if advanced treatment processes were implemented virtually at all wastewater treatment plants, but this would entail costs of about 4 billion euro/year for the European Union as a whole. We consider a "compromise" scenario where advanced treatment is required at plants of 100 thousand population equivalents (PE) or larger, or at plants between 10 and 100 thousand PE if the dilution ratio at the discharge point is 10 or less. Under this scenario, the length of the stream network exposed to high toxicity would not increase significantly compared to the previous scenario, and the other indicators would not deteriorate significantly, while the costs would remain at about 1.5 billion Euro/year. Arguably, costs could be further reduced, without a worsening of water quality, if we replace a local risk assessment to generic criteria of plant capacity and dilution in order to determine if a WWTP requires advanced treatment.

Clinical correlates of cerebral diffusion tensor imaging findings in chronic traumatic spinal cord injury.

STUDY DESIGN: Prospective clinical case-control study. OBJECTIVES: The aim of this study was to use diffusion tensor imaging (DTI) to assess the state of cerebral white matter tracts after spinal cord injury (SCI). The DTI metrics were evaluated in relation to neurological deficits and to the size and level of the spinal cord lesions. SETTING: Tampere University Hospital, Tampere, Finland. METHODS: Thirty-four patients (n=34) with clinically complete and incomplete SCI were evaluated using the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). DTI metrics (fractional anisotropy (FA) and apparent diffusion coefficient (ADC)) were calculated for multiple levels along the course of the corticospinal tract. The state of the spinal cord after injury was assessed using conventional magnetic resonance imaging (MRI). DTI parameters were compared with 40 orthopedically injured control subjects. RESULTS: Statistically significant differences in the DTI values between patients and controls were detected in the posterior area of the centrum semiovale. In this area, the FA values were lower in the patients compared with controls (P=0.008). For patients with clinically complete injury, the difference was even more significant (P=0.0005). Motor and sensory scores of the ISNCSCI correlated positively with FA and negatively with ADC values of the centrum semiovale. A moderate association was observed between the macroscopic changes in the spinal cord and the DTI abnormalities in the centrum semiovale. CONCLUSION: In patients with chronic SCI, DTI changes can be observed in the cerebral white matter. These alterations are associated with the clinical state of the patients.

Wernicke's encephalopathy: is diffusion-weighted MRI useful?

We present the clinical and magnetic resonance imaging (MRI) findings of five patients with acute Wernicke's encephalopathy. T2-weighted and fluid-attenuated inversion recovery (FLAIR) images demonstrated symmetrical hyperintense lesions within the dorsomedial thalami, periaqueductal white matter, and the tectum of the midbrain. None of the lesions enhanced with gadolinium. In addition to conventional MRI sequences, we performed diffusion-weighted imaging (DWI). In all patients, DWI showed symmetrical pathologic thalamic and midbrain signal hyperintensities more distinctly than did conventional T2-weighted or FLAIR sequences. The apparent diffusion coefficient (ADC) map images showed slight signal reductions in four patients, suggesting restricted diffusion within these regions. In one patient, the signal intensity within the affected thalami was isointense with the ipsilateral basal ganglia on ADC map images. For enhanced detection of pathology, we conclude that DWI should be included in the imaging protocols of patients suspected to suffer from Wernicke's encephalopathy.

Adverse long-term effects of brain radiotherapy in adult low-grade glioma patients.

OBJECTIVE: To study the long-term effects of radiotherapy on cognitive function in adult patients operated on for low-grade glioma. METHODS: A cohort of 160 patients who underwent surgery for low-grade gliomas of cerebral hemisphere between 1980 and 1992 in a single institution serving a defined population was studied. At a mean follow-up time of 7 years, 28 of the 101 patients who had postoperative irradiation (and no second surgery or chemotherapy) were still alive and eligible for MRI and neuropsychological study. Twenty-three of 59 patients who did not have radiotherapy, second surgery, or chemotherapy were alive and eligible at a mean of 10 years. RESULTS: The group that had postoperative irradiation performed significantly worse than the group that did not in cognitive tests. This difference was not accounted for by histologic diagnosis; location, extent of removal, or progression of the tumor; or any patient factor. Leukoencephalopathy was more severe in the group that had postoperative irradiation than in the group without radiotherapy, and correlated to poor memory performances only in the postoperative radiotherapy group. Average Karnofsky performance scale score was significantly lower in the group that had postoperative irradiation than in the group that did not. CONCLUSION: In adults with low-grade glioma, postoperative radiotherapy poses a significant risk of long-term leukoencephalopathy and cognitive impairment.

Importance of thyroid abnormalities detected at US screening: a 5-year follow-up.

PURPOSE: To clarify the natural history and frequency of thyroid echo abnormalities in a random adult population by performing a 5-year follow-up study of subjects of a previous thyroid ultrasonographic (US) screening study. MATERIALS AND METHODS: In the original survey, 253 randomly selected adults were screened by means of thyroid US. US abnormalities were detected in 69 subjects (27%). In the follow-up study, 57 (83%) of those 69 subjects who had abnormalities were reexamined by means of thyroid US, fine-needle aspiration biopsy (FNAB), blood tests, and clinical examination. RESULTS: Of 34 individual nodules, 12 (35%) had grown. Biopsy was performed in 10 of them. Nine were benign. One was equivocal, was excised, and proved to be an adenomatous nodule. Eight nodules (24%) had diminished or disappeared. Seven new focal lesions were found in seven subjects (12%). Biopsy was performed in five of these lesions, and they were benign. At 5-year follow-up, no thyroid malignancies were detected among subjects with echo abnormalities at the primary US screening. CONCLUSION: Thyroid US abnormalities occurring in a random adult population are predominantly benign and clinically unimportant.

Bilateral sphenoid wing metastases of prostate cancer presenting with extensive brain edema.

A 76-year-old man insidiously developed diffuse neurological symptoms: cognitive decline, dysphagia, dysphasia and mental disturbance. Computed tomography of the cranium revealed widespread bilateral brain edema and symmetrical bilateral sphenoid wing hyperostosis. Adjacent to the hyperostosis that resembled skull base meningiomas, two separate parenchymatous temporal lobe lesions enhancing with contrast medium were observed. The patient had earlier been diagnosed to have prostatic carcinoma. Dexamethasone therapy resulted in discontinuation of the neurological symptoms. The diagnosis of metastasized adenocarcinoma of the prostate was confirmed histologically on autopsy after a sudden death from pneumonia. Intracranial metastases of prostate cancer may have a predilection site at the sphenoid wing, and can mimic a skull base meningioma. Intracranial spread of prostatic adenocarcinoma should be considered in elderly men as a treatable cause of gradual neurological deterioration, especially if cranial malignancy or hyperostosis is found.

Spin-echo MRI of chronic intracerebral haematomas.

Our purpose was to characterise the MRI appearances of clinically non-neoplastic chronic intracerebral haematomas (ICH). We examined 25 patients with a history of clinically non-neoplastic 0.5-to 1.5-year-old ICH who underwent prospective follow-up 1.0-T spin-echo MRI of the brain. On T1-weighted images most lesions gave lower signal than white matter and were isointense with cerebrospinal fluid (CSF). On T2-weighted images most were either totally low-signal and slit-like, or had a high-signal centre and a low-signal margin. The low-signal (haemosiderin) rim showed areas of discontinuity in 7 cases. Of 24 lesions, 4 showed small enhancing areas on contrast-enhanced images. In 10 cases the brain parenchyma surrounding the lesion showed high-signal on T2- and low signal on T1-weighted images, probably representing encephalomalacia. In 20 cases enlargement of a nearby CSF space was observed, and 14 cases showed atrophy of the brain stem ipsilateral to the lesion. We thus found more variation on MRI of clinically non-neoplastic chronic ICH than previously described.

Interstitial radiotherapy of 25 parasellar/clival meningiomas and 19 meningiomas in the elderly. Analysis of short-term tolerance and responses.

I-125 seeds were permanently implanted into 25 parasellar-clival meningiomas (median age of patients, 56 y) and 19 globoid meningiomas in the elderly (median age of patients, 77 y) using stereotactic technique and 3-D dose planning. Total dose at the tumour margin was increased during the series from 100 Gy to 150 Gy. The procedure caused no mortality and no serious bleeding, but injury to the III cranial nerve due to puncture occurred in one (4%) of the 25 parasellar-clival meningiomas. In two (4.5%) of the 44 cases the postoperative CT scan showed a misplaced seed, located at the tumour surface. Nonenhancing hypodense rings developed around the seeds ('hot spots') with a median diameter of 10.5 mm at 12 months corresponding to a median initial activity of 8.7 mCi. In general, meningiomas responded by slow reduction in volume. The parasellar-clival meningiomas were followed-up for a median of 19 months (6-32), and so far 4 tumours have shrunk moderately, 13 slightly, and 5 not at all. Pre-operative III, V or VI cranial nerve signs were present in 17 patients and subsided in 8 of them. On the other hand, facial numbness developed or increased in 9 of the 25 patients, indicating that the V nerve is rather sensitive to this type of irradiation. In the 19 meningiomas of the elderly, the median follow-up time was 14 months (5-26). The median relative tumour volume was 46% at 12 months. Accounting for tumour-related deaths only, the actuarial survival rate was 78% at 12 months and 62% at 24 months. In general, brain oedema persisted despite reduction in tumour volume. Stereotactic implantation of I-125 seeds into intracranial meningiomas is relatively safe. Interstitial radiotherapy represents a potential tool in the control of medium-sized intracranial meningiomas with minimal brain oedema, but its long-term impact and untoward effects remain to be followed-up.

Ultrasound appearances in de Quervain's subacute thyroiditis with long-term follow-up.

In order to determine whether permanent echo abnormalities are produced by subacute thyroiditis, ultrasound examination of the thyroid was performed repeatedly after a mean interval of 23 months in 17 subjects (8 women and 9 men) aged 31-52 (mean 41) years, suffering from subacute thyroiditis. The diagnosis was based on typical clinical symptoms, and cytological confirmation was obtained in all subjects but one. In the primary phase the ultrasonic finding was in all cases abnormal, showing either diffuse or focal hypoechogenicity and enlargement of thyroid lobes. At follow-up, a homogenous echo structure was found in 15 patients. Nodularity was detected in only two subjects. It is concluded that permanent focal echo abnormalities are generally not produced by subacute thyroiditis. Consequently, thyroid nodules in subjects with a history of SAT should not be ignored.

Clinical versus ultrasound examination of the thyroid gland in common clinical practice.

In a prospective series of 72 patients, clinical and ultrasonographic examination of the thyroid gland were compared in detail. Normal-sized lobes were differentiated from enlarged ones both by inspection and by palpation. When lobar size was assessed by palpation, the estimate was most clearly influenced by increase in width. The correlation between two examiners in lobe size assessment was significant. In the classification of thyroid disease as diffuse, solitary, or multinodular, clinical examination and ultrasonography correlated significantly. However, only one third of the clinically solitary nodules proved to be solitary by ultrasound examination. Of 77 separate nodules, 43 escaped detection on clinical examination. Of these 43, 14 nodules exceeded 2 cm in diameter. It is concluded that the use of ultrasonography frequently alters the primary evaluation of thyroid nodularity based on palpation.

Thyroid gland: US screening in a random adult population.

High-frequency ultrasound examination of the thyroid was performed in 253 subjects (130 women and 123 men; age range, 19-50 years) that were randomly selected from the population in an area of Finland where goiter is not endemic. Thyroid echo abnormalities were detected in 69 subjects (27.3%). Prevalence of abnormalities increased with age, and women showed more lesions than did men in each of the 3 decades. The abnormality was solitary in 39 subjects (57%), multiple in 15 (22%), and diffuse in 15 (22%). Of the 68 individual nodules, 48 (70%) were smaller than 1 cm in diameter. Anechoic rounded nodules 1-5 mm in diameter were found in 28 subjects. Fine-needle aspiration biopsy was performed in 30 subjects. Cytologic examination revealed no unequivocal malignancies. In eight subjects (3.2%) with a diffuse echo abnormality, cytologic evaluation indicated lymphocytic thyroiditis. It is concluded that the prevalence of small thyroid echo abnormalities in a randomly selected adult population is rather high, a fact that supports use of a conservative approach to these types of findings.

Thyroid gland: US screening in middle-aged women with no previous thyroid disease.

To determine the prevalence of thyroid nodules in the healthy population, ultrasonography (US) of the thyroid gland was performed in 101 women aged 49-58 years in an urban area in southern Finland where goiter is not considered endemic. Subjects with any previous thyroid disease were excluded. Thyroid nodules or abnormalities of the echo structure were found in 36 (35.6%) subjects. Seventeen (47.2%) subjects had solitary nodules, 14 (38.9%) had multiple nodules, and five (13.9%) had diffuse abnormalities. Subjects with abnormal findings at US were further examined with fine-needle aspiration biopsy. Clinical examination and blood tests were performed for evaluation of levels of thyroxine, thyroid-stimulating hormone, and thyroid antibodies. One patient had a leukemic thyroid nodule, but no primary thyroid malignancies were found. In most cases, cytologic findings were benign and nonspecific, with a variable amount of degenerative changes. Three atoxic multinodular goiters and two cases of Hashimoto thyroiditis were detected. The results are in accordance with autopsy studies indicating that focal nodular changes of the thyroid gland are common in middle-aged women.

Ultrasonography of the thyroid during pregnancy.

To discover whether pregnancy causes ultrasonically detectable changes in the thyroid, an ultrasound examination of the thyroid was performed repeatedly in 21 pregnant women with no history of thyroid disease. Seven patients were examined three times and 14 twice during the course of pregnancy. The size of the thyroid was estimated and the echogenicity assessed with respect to homogenicity and degree by comparison with the echogenicity of adjacent muscles. The results were compared with the results of a control group of healthy female volunteers. The mean volume of the thyroid increased slightly during the course of pregnancy. No changes in the echogenicity or echostructure were noted.