Prognosis of Methanol Poisoning in a Developing Setting

BACKGROUND

Methanol-poisoning can be a challenging cause of mortality. Identifying the epidemiological, clinical, and para-clinical determinants of outcome in methanol-poisoning patients could be a step forward to its management.

METHODS

In this hospital-based cohort study, 123 methanol-poisoning patients were included. Data on background variables, details of methanol consumption, and laboratory assessments were recorded for each patient. Patients underwent brain CT scans without contrast. We evaluated the association of all gathered clinical and para-clinical data with patients' outcome and length of hospital stay (LOS). Independent association of potential determinants of death, and LOS were modeled applying multivariable logistic, and Ordinary Least Square regressions, respectively. Odds ratio (OR), and regression coefficient (RC), and their 95% confidence intervals (CIs) were estimated.

RESULTS

Most of the study population were male (n=107/123). The mean age of the participants was 30.3±9.1 years. Ninety patients (73.2%) were reported as being conscious on admission, and 34.3% of patients were identified with at least one abnormality in their CT scan. Level of consciousness (LOC) (OR: 42.2; 95% CI: 2.35-756.50), and blood pH (OR: 0.37; 95% CI: 0.22-0.65) were associated with death. Supratentorial edema (RC: 17.55; 95% CI: 16.95-18.16) were associated with LOS.

CONCLUSION

Besides LOC, patients with any abnormality in their brain CT scan on admission were found to be at higher risk of death, and patients with supratentorial edema were at risk of longer LOS. Brain CT-scan on admission should be considered as a part of the routine procedure during the management of methanol-poisoning.

Essential thrombocythemia associated with fibrosis involving bilateral renal sinuses: A case report

Essential thrombocythemia (ET) is associated with an increased risk of thrombosis and autoimmune renal involvement. We report an extremely rare case of an acute kidney injury (AKI) in the presence of bilateral renal pelvises fibrosis in a patient with a proven diagnosis of ET. A 48-year-old male patient with a past medical history of mild chronic kidney disease and ET was admitted to our hospital with AKI. The patient discontinued his hydroxyurea treatment for the past 2 months and laboratory data showed increasing serum creatinine levels and platelet counts with increased renal sizes, severe hydrocalyx, and bilateral renal sinuses' fibrosis in imaging. The patient started again on hydroxyurea therapy and showed improvement in all laboratory scales. ET and increased levels of platelet-derived growth factors could cause renal sinuses fibrosis and glomerulopathy. In ET patients with renal sinuses' fibrosis and glomerulopathy, initiating cytoreductive therapy could improve the outcome.

A comparative study of three-dimensional airway changes after fibula flap reconstruction for benign and malignant tumours in the anterior mandible

Surgical treatment of tumours in the anterior mandible and surrounding tissues may result in defects which can be restored by a fibula free flap. The upper airway may change during this process. The purpose of this retrospective study was to evaluate upper airway changes after fibula free flap reconstruction. A total of 37 patients who underwent anterior mandibulectomy and fibula free flap reconstruction between 2012 and 2020 were recruited. Patients with benign and malignant tumours involving the anterior mandible were included. Spiral computed tomography was performed 1 week preoperatively, 1 week postoperatively, and at> 1 year (range 12-23 months) after surgery. Cross-sectional areas and volumes of the upper airway were measured. Data were analysed by two-way analysis of variance. The upper airway in the malignant tumour group showed an increasing trend, especially at the soft palate and tongue base levels (P < 0.01). In the benign tumour group, the upper airway showed no significant changes. The location of the minimum cross-sectional area moved downwards in both groups, and the area increased in the malignant tumour group during long-term follow-up. Upper airway obstruction is less likely to occur in the long term after surgical resection of anterior mandible malignancies and fibula free flap reconstruction.

Towards a benchmark of abdominal CT use during duty shifts: 15-year sample from the Netherlands

Purpose

To investigate temporal changes in the utilization and patient impact of abdominal CT during duty shifts in the past 15 years.

Methods

This study included a random sample of 1761 abdominal CT scans that were made during evening and night duty shifts in a tertiary care center between 2005 and 2019.

Results

The number of CT scans significantly increased (almost threefold) between 2005 and 2019 (Mann–Kendall tau of 0.829, P < 0.001). The proportion of negative CT scans (i.e., the absence of findings related to the reason that the CT scan was made and no disease deterioration or other new and clinically relevant findings compared to a previous imaging examination when available) was 40.0% (700/1749) in the entire 15-year study frame and did not significantly change over time (Mann–Kendall tau of − 0.219, P = 0.276). The overall frequency of same-day hospital discharge after negative CT was 20.6% (150/729) in the past 15 years and showed a significant increase over time (Mann–Kendall tau of 0.505, P = 0.010). The overall proportion of CT scans with incidental findings was 3.4% (60/1761) and remained statistically stable over the past 15 years (Mann–Kendall tau of − 0.057, P = 0.804).

Conclusion

Over the past 15 years, the number of CT scans and the frequency of same-day hospital discharge after negative CT have increased, while the proportions of negative CT scans and incidental findings have remained stable in our tertiary care center. The data from this study can be used for interinstitutional benchmarking to define, monitor, and improve the appropriateness of imaging utilization.

Spiral breast computed tomography (CT): signal-to-noise and dose optimization using 3D-printed phantoms

Objectives

To investigate the dependence of signal-to-noise ratio (SNR) and calculated average dose per volume of spiral breast-CT (B-CT) on breast size and breast density and to provide a guideline for choosing the optimal tube current for each B-CT examination.

Materials and methods

Three representative B-CT datasets (small, medium, large breast size) were chosen to create 3D-printed breast phantoms. The phantoms were filled with four different agarose-oil-emulsions mimicking differences in breast densities. Phantoms were scanned in a B-CT system with systematic variation of the tube current (6, 12.5, 25, 32, 40, 50, 64, 80, 100, 125 mA). Evaluation of SNR and the average dose per volume using Monte Carlo simulations were performed for high (HR) and standard (STD) spatial resolution.

Results

SNR and average dose per volume increased with increasing tube current. Artifacts had negligible influence on image evaluation. SNR values ≥ 35 (HR) and ≥ 100 (STD) offer sufficient image quality for clinical evaluation with SNR being more dependent on breast density than on breast size. For an average absorbed dose limit of 6.5 mGy for the medium and large phantoms and 7 mGy for the small phantom, optimal tube currents were either 25 or 32 mA.

Conclusions

B-CT offers the possibility to vary the X-ray tube current, allowing image quality optimization based on individual patient’s characteristics such as breast size and density. This study describes the optimal B-CT acquisition parameters, which provide diagnostic image quality for various breast sizes and densities, while keeping the average dose at a level similar to digital mammography.

Key Points

• Image quality optimization based on breast size and density varying the tube current using spiral B-CT.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00330-020-07549-3.

Comparison of clinical diagnostic value of spiral CT with different dose in patients with early-stage peripheral lung cancer

PURPOSE

To compare the clinical diagnostic value of spiral CT scan with different dose in patients with early-stage peripheral lung cancer.

METHODS

A total of 163 cases of patients with early-stage peripheral lung cancer who came to People's Hospital of Rizhao for treatment from June 2014 to January 2017 were retrospectively analyzed. A total of 78 cases of patients who received low-dose CT scanning were the low-dose group, another 84 cases of patients who received routine dose CT scanning were the routine dose group. Multislice helical CT (MSCT) scanning was performed in both groups, with tube voltage of 120 kV. Tube current was 25 m A in the low-dose group and 250 m A in the routine dose group. In addition, a total of 80 patients with lobar pneumonia were added as the control group of diagnostic sensitivity, specificity and accuracy. Pathological diagnosis was taken as the gold standard to compare the diagnostic sensitivity, specificity and accuracy of the two groups.

RESULTS

The image quality, nodules and signs of the two groups were compared, and the results of radiation dose of the two groups were compared. The diagnostic sensitivity, specificity and accuracy of the low-dose group were 82.05%, 87.50% and 84.81%, respectively. The diagnostic sensitivity, specificity and accuracy of the routine dose group were 85.71%, 86.25% and 85.97%, respectively. The diagnostic value of the two groups was not statistically significant (p > 0.05). However, the radiation dose in the low-dose group was significantly lower than that in the routine group.

CONCLUSION

Low-dose MSCT scanning can meet the clinical requirements for imaging diagnosis of peripheral lung cancer, and can reduce the radiation dose of patients.

Clinical guiding significance of abdominal organs projection on the lateral lumbar X-ray for spinal microendoscopy punctures

Aims: To measure the anatomical structure of lumbar spine by computed tomography (CT) scan, and explore the posterior edge of abdominal organs on the lateral lumbar X-ray in lateral puncture, in order to provide an anatomical basis for spinal microendoscopy to avoid abdominal organ injury. Methods: A total of 50 patients with abdominal enhanced CT scan in our hospital were included. The spine from L1 to S1 were divided into 16 axial levels (containing the superior level of vertebral body, middle part of vertebral body, and inferior level of vertebral body) to make out safety zone, critical puncture point and critical angle in accordance with the anatomical position of posterior renal fascia and parietal peritoneum on the lateral lumbar X-ray. Results: From L1 to S1, the projection of the lowest point of the posterior renal fascia and parietal peritoneum and the projection of the critical puncture point turns from the dorsal side of the posterior vertebral body to the ventral side. And the two projection points are in the same position on the middle level of L4 vertebral body, which is on the posterior margin of L4 vertebral body. The critical puncture angle is also gradually reduced, and is approximate 0° at the middle level of L4. There is no statistically significant difference between left and right side of the body. Conclusion: The safety zone, critical puncture point and critical angle of L1-S1 were determined in accordance with the projection of the lowest point of the posterior renal fascia and parietal peritoneum, which provided an anatomical guidance for avoiding the injury of posterior renal fascia or abdominal organs during operation.

Increased urinary bladder volume improves the detectability of urinary stones at the ureterovesical junction in non-enhanced computed tomography (NECT)

OBJECTIVES

To evaluate the influence of the urinary bladder volume on the detectability of urolithiasis at the ureterovesical junction (UVJ) using a low-dose CT (LD-CT) with iterative reconstruction (IR) and a standard-dose CT (SD-CT) without IR in a large cohort.

METHODS

Four hundred patients (278 males (69.5%), mean 44.6 ± 14.7 years) with urolithiasis at the UVJ were investigated either by an LD-CT with IR (n = 289, 72%) or an SD-CT without IR (n = 111, 28%) protocol. The detectability of distal urolithiasis was assessed by a dichotomous assessment (definite or questionable) by two radiologists in consensus and by a quantitative analysis of the signal density distribution across a line drawn parallel to the distal ureter. Based on the resulting graph, minimum/maximum density values and mean/maximum upslopes and downslopes were derived and calculated automatically. In all patients, the total bladder volume was calculated by a slice-by-slice approach on axial CT images.

RESULTS

Patients with definite stones showed significantly higher urinary bladder volumes compared to patients with questionable stones in both LD-CT and SD-CT (p < 0.01). These results were independent of stones' length and patients' BMI values. Using cutoffs of 92 ml for LD-CT and 69 ml for SD-CT, high positive predictive values/accuracy rates of 96%/85% (LD-CT) and 98%/86% (SD-CT) were observed to identify definite urinary stones.

CONCLUSIONS

Urinary bladder volume has a significant impact on the detectability of distal urolithiasis. Moderate bladder filling by pre-CT hydration with subsequent CT scan at the time of high urge to void increases the detectability of urinary stones at the UVJ in clinical routine.

KEY POINTS

• Urinary bladder volume significantly affects the detectability of distal urolithiasis • Higher bladder volumes are associated with improved detectability of distal urinary stones • Oral pre-CT hydration for urolithiasis is easily applicable and cost-effective.

Volumetric Evaluation of Different Obturation Techniques in Primary Teeth Using Spiral Computed Tomography

BACKGROUND

Various obturation techniques have been evaluated for better filling of the root canals in primary teeth using different methods. Spiral Computed Tomography (SCT) is a new revolution in the pediatric endodontics for assessment of quality of the obturation from 3 dimensions.

OBJECTIVES

To evaluate the efficiency of 5 different obturation methods in delivering the filling material into the canals of primary teeth using Spiral Computed Tomography scan.

STUDY DESIGN

A total of 50 canals of primary teeth were prepared, divided into 5 groups with 10 canals in each group and obturated with Zinc Oxide Eugenol cement using 5 different obturation techniques such as Local anesthetic syringe, Tuberculin syringe, Endodontic plugger, hand held Lentulo-spiral, and Lentulo-spiral mounted on slow speed hand piece. The pre and post obturation volume and finally the Percentage of Obturated Volume (POV) were calculated using SCT scan for each group. The data obtained was statistically analyzed using One-way Analysis of Variance (ANOVA) and Tukey's post-hoc test.

RESULTS

Lentulo-spiral hand held showed highest POV value followed by Lentulospiral mounted to hand piece, Tuberculin syringe and Endodontic plugger; whereas Anesthetic syringe had least POV (P < 0.05).

CONCLUSION

Lentulo-spiral hand held is the best obturating technique among the 5 groups evaluated as the canals of this group showed maximum percentage of filled material. However, a further study with large sample size is highly essential.

Assessment of the proximity between the mandibular third molar and inferior alveolar canal using preoperative 3D-CT to prevent inferior alveolar nerve damage

BACKGROUND

The inferior alveolar nerve (IAN) may be injured during extraction of the mandibular third molar, causing severe postoperative complications. Many methods have been described for evaluating the relative position between the mandibular third molar and the inferior alveolar canal (IAC) on panoramic radiography and computed tomography, but conventional radiography provides limited information on the proximity of these two structures. The present study assessed the benefits of three-dimensional computed tomography (3D-CT) prior to surgical extraction of the mandibular third molar, to prevent IAN damage.

METHODS

This retrospective study included 4917 extractions in 3555 patients who presented for extraction of the mandibular third molars. The cases were classified into three groups, according to anatomical relationship between the mandibular third molars and the IAC on panoramic radiography and whether 3D-CT was performed. Symptoms of IAN damage were assessed using the touch-recognition test. Data were compared using the chi-square test and Fisher's exact test.

RESULTS

Among the 32 cases of IAN damage, 6 cases were included in group I (0.35 %, n = 1735 cases), 23 cases in group II (1.1 %, n = 2063 cases), and 3 cases in group III (0.27 %, n = 1119 cases). The chi-square test showed a significant difference in the incidence of IAN damage between groups I and II. No significant difference was observed between groups I and III using Fisher's exact test. In the 6 cases of IAN damage in group I, the mandibular third molar roots were located lingual relative to the IAC in 3 cases and middle relative to the IAC in 3 cases. The overlap was ≥2 mm in 3 of 6 cases and 0-2 mm in the remaining 3 cases. The mean distance between the mandibular third molar and IAC was 2.2 mm, the maximum distance 12 mm, and the minimum distance 0.5 mm. Greater than 80 % recovery was observed in 15 of 32 (46.8 %) cases of IAN damage.

CONCLUSIONS

3D-CT may be a useful tool for assessing the three-dimensional anatomical relationship and proximity between the mandibular third molar and IAC in order to prevent IAN damage during extraction of mandibular third molars.

Type II canal configuration and Type I Dens invaginatus

The prevalent notion about maxillary central incisor with normal external morphology is a tooth with single root and root canal. A case in which all four maxillary incisors were having Type II canal configurations (Vertucci's classification) is reported, in addition, the lateral incisors revealed dens invaginatus with a Type I pattern as suggested by Ohler's classification and a large periapical lesion was seen in relation to the right lateral incisor. The diagnosis was confirmed with the aid of spiral computed tomography (CT) and canals obturated. Nonsurgical healing of the lesion was assessed by reviewing the case at prefixed intervals of time.

Three Dimensional Spiral CT Imaging of the Musculoskeletal System: Application and Advantages

BACKGROUND

Clinical applications of spiral computed tomography (CT) have increased extensively over the past decade and continue to widen rapidly. The introduction of three-dimensional(3-D) reconstruction in CT technology has revolutionized medical imaging. This advancement has been possible due to the combination of spiral computed tomography and various 3-D reconstruction protocols which have permitted rapid and comprehensive examination of all regions of the body. It has unequivocal advantages in the preoperative planning of craniofacial surgery, assessment of complex fractures of the skeletal system especially pelvis and in the surgical treatment of dysplastic hips in children.

METHODS

3-D spiral CT imaging of various parts of the musculoskeletal system was carried out in 60 cases using available protocols, at the CT scan center of a large tertiary care service hospital.

RESULTS

The study provided a new approach in the analysis of complex anatomic relationships of the musculoskeletal system. Therapeutic planning whether surgical or medical was to a great extent aided by the anatomic information available from these images.

CONCLUSION

3-D CT imaging is a rapid, non-invasive and accurate technique for diagnosis, pre-operative evaluation as well as post-operative assessment of a large number of musculoskeletal diseases. 3-D CT studies have come to stay and with continued improvement in CT technology it has now become an integral part of imaging studies of the musculoskeletal system.

Imaging detection of new HCCs in cirrhotic patients treated with different techniques: Comparison of conventional US, spiral CT, and 3-dimensional contrast-enhanced US with the Navigator technique (Nav 3D CEUS)()

INTRODUCTION

The commercially available Navigator system(©) (Esaote, Italy) allows easy 3D reconstruction of a single 2D acquisition of contrast-enhanced US (CEUS) imaging of the whole liver (with volumetric correction provided by the electromagnetic device of the Navigator(©)). The aim of our study was to compare the efficacy of this panoramic technique (Nav 3D CEUS) with that of conventional US and spiral CT in the detection of new hepatic lesions in patients treated for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

From November 2006 to May 2007, we performed conventional US, Nav 3D CEUS, and spiral CT on 72 cirrhotic patients previously treated for 1 or more HCCs (M/F: 38/34; all HCV-positive; Child: A/B 58/14) (1 examination: 48 patients; 2 examinations: 20 patients; 3 examinations: 4 patients). Nav 3D CEUS was performed with SonoVue(©) (Bracco, Milan, Italy) as a contrast agent and Technos MPX(©) scanner (Esaote, Genoa, Italy). Sensitivity, specificity, diagnostic accuracy, and positive and negative predictive values (PPV and NPV, respectively) were evaluated. Differences between the techniques were assessed with the chi-square test (SPSS release-15).

RESULTS

Definitive diagnoses (based on spiral CT and additional follow-up) were: 6 cases of local recurrence (LocRecs) in 4 patients, 49 new nodules >2 cm from a treated nodule (NewNods) in 34 patients, and 10 cases of multinodular recurrence consisting of 4 or more nodules (NewMulti). The remaining 24 patients (22 treated for 1-3 nodules, 2 treated for >3 nodules) remained recurrence-free. Conventional US correctly detected 29/49 NewNods, 9/10 NewMultis, and 3/6 LocRecs (sensitivity: 59.2%; specificity: 100%; diagnostic accuracy: 73.6%; PPV: 100%; NPV: 70.1%). Spiral CT detected 42/49 NewNods plus 1 that was a false positive, 9/10 NewMultis, and all 6 LocRecs (sensitivity: 85.7%; specificity: 95.7%; diagnostic accuracy: 90.9%; PPV: 97.7%; NPV: 75.9%). 3D NAV results were: 46N (+9 multinodularN and 6 LR), 3 false-negatives, and one false-positive (sensitivity: 93.9; specificity: 97.9%; diagnostic accuracy: 95.6; PPV: 97.9; NPV: 93.9).

CONCLUSIONS

3D Nav CEUS is significantly better than US and very similar to spiral CT for detection of new HCCs. This technique revealed the presence of lesions that could not be visualized with spiral CT.

Diagnostic value of spiral CT for detecting colon carcinoma in senile patients: an analysis of 162 cases

AIM: To evaluate the diagnostic value of spiral CT for detecting colon carcinoma in senile patients.

METHODS: One hundred and sixty-two senile colon cancer patients were confirmed by operation and histological examination. All of them received spiral CT or colonoscopy examination. The diagnostic value of spiral CT was compared with that of colonoscopy.

RESULTS: All patients received spiral CT scan and 75.3% of the patients received colonoscopy examination. A total of 40 patients did not finish the colonoscopy examination; 27 of these (16.67%) were intolerant of colonoscopy examination because of coronary heart disease and hypertension. The accuracy rate of spiral CT in the diagnosis of colon carcinoma was 80.86%, which was significantly higher than that of colonoscopy examination (70.37%, P < 0.05).

CONCLUSION: Spiral CT is a safe, painless and convenient method for detecting colon cancer and its metastasis. It is more suitable for the diagnosis of colon carcinoma in senile patients.

Spiral CT Angiography: Applications in Neurovascular Imaging

BACKGROUND

The advent of Spiral Computed Tomographic (CT) angiography has provided the patients a non-invasive, accurate and fast modality of imaging the vasculature.

METHODS

Spiral CT angiography was performed in 30 patients to evaluate intracranial circulation using standard protocols of data acquisition. The images were processed and reconstructed in 3-dimension to delineate anatomy and pathology accurately.

RESULTS

The study established that CT angiography is an accurate modality for evaluating the intracranial circulation in a variety of abnormalities. It is safe both in terms of being non-invasive and exposure to radiation. It has a distinct advantage over other non-invasive modalities of imaging like MRI in the evaluation of patients with metallic stents and clips.

CONCLUSION

CT angiography has tremendous potential in imaging the intracranial vasculature. It is unquestionably safer than catheter angiography as it avoids arterial puncture and intra-arterial catheter manipulation. It is fast and capable of producing excellent 3-dimensional images of the intracranial vasculature.

Vascular applications of Spiral CT : an initial Experience

Since the clinical introduction of computed tomography (CT) in the mid 1970s, several technological and clinical advances have improved image quality and reduced scanning time. During the past decade technological breakthroughs have ushered in an exciting advance in medical imaging : spiral CT. Spiral CT technology with its high speed and volumetric data acquisition has spawned a new vascular imaging technique - spiral CT angiography which is noninvasive, accurate, faster and less expensive than conventional angiography. We report our experience of having performed 100 CT angiographies with 3-D reconstructions of various vascular territories of the body. Details of technique of data acquisition, methods of 3-D reconstruction and clinical applications are discussed.