Meckel Gruber Syndrome--a case report

Meckel Gruber Syndrome is a rare syndrome inherited as Mendelian autosomal recessive condition. The affected infant usually has a large occipital encephalocoele associated with renal cysts and sometimes polydactyly. The prognosis is poor. The affected child is still born or dies early in infancy. If diagnosis is done by prenatal ultrasound examination termination of pregnancy can be done.

HRCT diagnosis of diffuse parenchymal lung disease: inter-observer variation

BACKGROUND

This study was designed to measure inter-observer variation between thoracic radiologists in the diagnosis of diffuse parenchymal lung disease (DPLD) using high resolution computed tomography (HRCT) and to identify areas of difficulty where expertise, in the form of national panels, would be of particular value.

METHODS

HRCT images of 131 patients with DPLD (from a tertiary referral hospital (n = 66) and regional teaching centres (n = 65)) were reviewed by 11 thoracic radiologists. Inter-observer variation for the first choice diagnosis was quantified using the unadjusted kappa coefficient of agreement. Observers stated differential diagnoses and assigned a percentage likelihood to each. A weighted kappa was calculated for the likelihood of each of the six most frequently diagnosed disease entities.

RESULTS

Observer agreement on the first choice diagnosis was moderate for the entire cohort (kappa = 0.48) and was higher for cases from regional centres (kappa = 0.60) than for cases from the tertiary referral centre (kappa = 0.34). 62% of cases from regional teaching centres were diagnosed with high confidence and good observer agreement (kappa = 0.77). Non-specific interstitial pneumonia (NSIP) was in the differential diagnosis in most disagreements (55%). Weighted kappa values quantifying the likelihood of specific diseases were moderate to good (mean 0.57, range 0.49-0.70).

CONCLUSION

There is good agreement between thoracic radiologists for the HRCT diagnosis of DPLD encountered in regional teaching centres. However, cases diagnosed with low confidence, particularly where NSIP is considered as a differential diagnosis, may benefit from the expertise of a reference panel.

Primary adenocarcinoma of the vermiform appendix: a case report

Primary adenocarcinoma of the appendix is rare, and since Berger first recognised the neoplasm in 1882, fewer than 250 cases have been recorded. Adenocarcinoma of the appendix is never suspected pre-operatively, being usually first discovered by histological examination. Ileocaecal resection during the first operation and right hemicolectomy for a carcinoma diagnosed after appendicectomy remain the main stay of treatment.

Hypoplasia of the abdominal aorta--a case report

Infrarenal aortic coarctation is a very uncommon vascular disease. It has been named as hypoplasia of abdominal aorta, mid aortic dysplasia, mid aortic syndrome, atrophy of aorta, atresia of the terminal aorta & atypical coarctation. The pathogenesis is still controversial. Hypertension is an almost universal feature of this disorder. We present a case report with postmortem findings of a young female patient having hypoplasia of abdominal aorta for its rarity.

Nodular and diffuse fibrous proliferation of tunica vaginalis--a case report

A case of nodular and diffuse fibrous proliferation (NDFP) of the tunica vaginalis testis occurring in a 40 year male is described. Immunohistochemistry confirmed fibroblastic origin. Histogenesis & differential diagnosis of this lesion is considered. Simple excision of this lesion is curative. The lesion is very rare but it is important that both surgeons & pathologists become aware of this entity to avoid radical orchiectomy in young patients.

Smoking-related interstitial lung diseases: histopathological and imaging perspectives

The present review focuses on the interstitial lung diseases related to smoking. Thus, the pathology and radiology of Langerhans cell histiocytosis, desquamative interstitial pneumonia, respiratory bronchiolitis and respiratory bronchiolitis-associated-interstitial lung disease are considered. The more tenuous association between pulmonary fibrosis and smoking is also discussed.

Leiomyosarcoma of the scrotum

A case of leiomyosarcoma of the scrotum is reported for its rarity. The tumor measured 6.2 x 4 x 4 cm and presented as a gradually increasing painless mass of 1 month duration. Light microscopy showed the typical interlacing fascicles of neoplastic cells with mitotic count of 1-2 / 10 HPF in different areas. Immunoperoxidase stains of vimentin & desmin and electron microscopy confirmed its muscle origin.

An unusual case of pneumonia

A previously healthy 37-year-old man was admitted with a two-month history of increasing shortness of breath and high temperature. A chest X-ray demonstrated bibasal shadowing and small bilateral pleural effusions; arterial blood gases demonstrated low pO2. Despite intravenous antibiotics no significant improvement was observed. A high-resolution chest computed tomography showed diffuse ground-glass opacification with segmental and subsegmental airways opacification, indicating fine fibrosis. Subsequently, open lung biopsy showed diffuse alveolar damage and a histopathological diagnosis of acute interstitial pneumonia (Hamman-Rich syndrome) was made. Antibiotics were stopped and high intravenous doses of steroids were given with a dramatic improvement in the patient's breathing and radiographic findings. The pathophysiological mechanisms of acute interstitial pneumonia and current therapeutic options are discussed.

A comparison of serial computed tomography and functional change in bronchiectasis

In bronchiectasis the morphological determinants of (marginal) fluctuations in pulmonary function tests are uncertain. The aim of the present study was to evaluate serial computed tomography (CT) changes in relation to pulmonary function trends in patients with bronchiectasis. The relationships between pulmonary function indices and CT scans in 48 adult patients with bronchiectasis were evaluated at baseline and at follow-up, at a median interval of 28 months (range 6-74 months). Two independent observers semiquantitatively scored CT features of bronchial and small airways disease. At initial assessment, the severity of airflow obstruction was linked primarily to the extent of mosaic attenuation. However, serial changes in pulmonary function indices were only associated with serial changes in mucous plugging scores. Alterations in mucous plugging on serial CT were associated with changes in the severity of bronchiectasis and bronchial wall thickness. Greater severity of all three morphological abnormalities at baseline CT were predictive of significant declines in forced expiratory volume in one second, with severe bronchial wall thickness being the most adverse prognostic determinant. Variations in mucous plugging on computed tomography correlate with minor fluctuations in pulmonary function tests in bronchiectasis. However, the severity of bronchial wall thickness is the primary determinant of subsequent major functional decline.

Nonspecific interstitial pneumonia and usual interstitial pneumonia: comparative appearances at and diagnostic accuracy of thin-section CT

PURPOSE

To compare the morphologic abnormalities on thin-section computed tomographic (CT) images in a group of patients with histopathologically confirmed nonspecific interstitial pneumonia (NSIP) or usual interstitial pneumonia (UIP) and a clinical presentation of idiopathic pulmonary fibrosis.

MATERIALS AND METHODS

Thin-section CT imaging patterns and distribution of disease in 53 patients with histologic diagnoses of NSIP (n = 21) or UIP (n = 32) were quantified retrospectively and independently by four observers. The appearances of NSIP and UIP at CT were compared with univariate and multivariate techniques.

RESULTS

The use of thin-section CT proved to have moderate sensitivity (70%), specificity (63%), and accuracy (66%) in the diagnosis of NSIP. An increased proportion of ground-glass attenuation was the cardinal feature of NSIP at CT (odds ratio: 1.04 for each 1% increase in the proportion of ground-glass attenuation). A histologic diagnosis of NSIP was most frequent (in 24 of 35 observations [69%]) when ground-glass attenuation predominated, and was more frequent with mixed (35 of 79 observations [44%]) than with predominantly reticular disease (25 of 98 [26%] observations, P < .005). Logistic regression analysis of the data indicated that misdiagnosis of UIP in patients with NSIP was associated with less ground-glass attenuation (P < .005) at CT and a subpleural disease distribution (P = .02), with the converse being true for UIP cases misdiagnosed as NSIP.

CONCLUSION

In patients with a clinical presentation of idiopathic pulmonary fibrosis, the accuracy of thin-section CT in identifying NSIP is considerably higher than previously reported. At CT, NSIP is characterized by more ground-glass attenuation and a finer reticular pattern than is UIP. Nevertheless, considerable overlap in thin-section CT patterns exists between NSIP and UIP.

Acute respiratory distress syndrome caused by pulmonary and extrapulmonary injury: a comparative CT study

PURPOSE

To determine computed tomographic (CT) differences between acute respiratory distress syndrome (ARDS) due to pulmonary injury (ARDS(p)) and extrapulmonary injury (ARDS(ex)).

MATERIALS AND METHODS

CT appearances in 41 patients (27 male, 14 female; mean age, 47.1 years +/- 17.1 [SD]; age range, 17-79 years; those with ARDS(p), n = 16; those with ARDS(ex), n = 25) were categorized as typical or atypical of ARDS by two observers. The extent of individual CT patterns was also quantified.

RESULTS

Typical CT appearances were more frequent in ARDS(ex) than ARDS(p) (18 [72%] of 25 vs five [31%] of 16 patients, respectively; P <.01). Sensitivity, specificity, and accuracy of a typical CT pattern for the diagnosis of ARDS(ex) were 72%, 69%, and 71%, respectively. Atypical appearances were characterized by more extensive nondependent intense parenchymal opacification (IPO) (P =.03) and cysts (P =.05), whereas typical CT appearances had more extensive dependent IPO (P =.01). Typical appearances at CT were independently related to the cause of ARDS (odds ratio, 8.9; 95% CI: 1.8, 44.2; P <.01) but were independent of the time from intubation. Foci of nondependent IPO were more extensive in ARDS(p) (P =.05) than ARDS(ex), but this finding was ascribable to differences in time to CT (after intubation) between ARDS(p) and ARDS(ex).

CONCLUSION

The differentiation between ARDS(p) and ARDS(ex) can, with some caveats, be based on whether the CT appearances are typical or atypical of ARDS but not on any individual CT pattern in isolation.

Gradient correction and classification of CT lung images for the automated quantification of mosaic attenuation pattern

PURPOSE

The detection of density differences, or "mosaic attenuation pattern," on CT images may be difficult when the regional inhomogeneity of the density of the lung parenchyma is subtle. The purpose of this work was to develop a fully automated method for the reproducible quantification of the underattenuated areas of the lung parenchyma. This technique may be useful in increasing the precision of investigation of structure/function relationships.

METHOD

Anatomical segmentation was achieved by a structure-filtering operator based on mathematical morphology. To compensate for the density gradient visible on lung CT scans, a model-based iterative deconvolution filter and an adaptive clustering algorithm were developed. Validation was performed with CT images from a lung phantom, 15 patients with constrictive obliterative bronchiolitis, and 8 normal subjects.

RESULTS

The accuracy of the estimate of the density gradient on phantom studies was 93.3%. The automated quantification of the areas of decreased attenuation on scans of constrictive obliterative bronchiolitis was within 8.2% from the average scoring of two experienced observers.

CONCLUSION

The proposed technique is fully automated and can accurately correct for density gradient and classify areas of decreased attenuation on lung CT images.

Evaluation of patients undergoing lung volume reduction surgery: ancillary information available from computed tomography

AIM

A number of imaging techniques have been used for the pre-operative assessment of patients for lung volume reduction surgery (LVRS). We evaluated whether data currently acquired from perfusion scintigrams and cine MR of the diaphragm are obtainable from high resolution CT (HRCT) of the thorax.

MATERIALS AND METHODS

Thirty patients taking part in a randomized controlled trial of LVRS against maximal medical therapy were evaluated. HRCT examinations (n= 30) were scored for (i) the extent and distribution of emphysema; (ii) the extent of normal pulmonary vasculature; and (iii) diaphragmatic contour, apparent defects and herniation. On scintigraphy, (n= 28), perfusion of the lower thirds of both lungs, as a proportion of total lung perfusion (LZ/T(PERF)), was expressed as a percentage of predicted values (derived from 10 normal control subjects). On cine MR (n= 25) hemidiaphragmatic excursion and coordination were recorded.

RESULTS

Extensive emphysema was present on HRCT (60% +/- 13.2%). There was strong correlation between the extent of normal pulmonary vasculature on HRCT and on perfusion scanning (r(s)= 0.85, P< 0.00005). Hemidiaphragmatic incoordination on MR was weakly associated with hemidiaphragmatic eventration on HRCT (P= 0.04).

CONCLUSION

The strong correlation between lung perfusion assessed by HRCT and lung perfusion on scintigraphy suggests that perfusion scintigraphy is superfluous in the pre-operative evaluation of patients with emphysema for LVRS.

Rhabdoid tumour of the kidney: a diagnostic challenge and a fatal outcome

Rhabdoid tumour of the kidney is not common. Presentation of such a lethal tumour along with blunt abdominal trauma is even rarer. We report such a case of Rhabdoid tumour of kidney which presented as renal trauma, and discuss the diagnostic difficulties and rapidly fatal outcome.

Visual quantitation and observer variation of signs of small airways disease at inspiratory and expiratory CT

Areas of decreased pulmonary attenuation representing small airways disease can be identified on computed tomography (CT). The objective was to quantify differences between inspiratory and expiratory CT for the detection of signs of small airways disease by four observers. Observer variation and the superiority of a fine versus a coarse grading system were also evaluated. Inspiratory and expiratory CT scans of 106 patients with conditions characterized by small airways disease and 19 healthy individuals were assessed by four observers. The extent of decreased attenuation was scored on a fine scale to the nearest 5% and also semiquantitatively on a coarser 5-point scale. Decreased attenuation was more extensive on expiratory CT (median. 6.7%; 0-76.7%) than on inspiratory CT (median, 3.8%; 0-81.7%). The fine scoring system had unacceptable interobserver variation (coefficient of variation, 80% for inspiratory CT, 70% for expiratory CT). The semiquantitative system had acceptable interobserver agreement (inspiratory CT k(w) = 0.64; expiratory CT, k(w) = 0.69) and good intra-observer agreement (inspiratory CT, k(w) = 0.80; expiratory CT, k(w) = 0.64). The major CT sign of small airways disease is more confidently quantified on expiratory CT. A fine scoring system is associated with unacceptable observer variation, and a coarse semiquantitative system is more suitable for quantitative studies of small airways disease.

A comparison of methods for enhancing the detection of areas of decreased attenuation on CT caused by airways disease

PURPOSE

The purpose of this work was to investigate thin section CT image enhancement of subtle areas of decreased attenuation of the lung parenchyma in suspected airways disease.

METHOD

Forty-seven consecutive patients with chronic sputum production underwent pulmonary function tests and high resolution CT (HRCT). Single section inspiratory (INSP), expiratory (EXP), and minimum intensity projection (MINIP) images through the lower lobes were acquired. A histogram stretch was applied to the INSP and MINIP images, generating two further image formats. The five image types were compared for the extent of decreased attenuation, observer confidence, and correlations with pulmonary function tests.

RESULTS

Interobserver variation was lowest with MINIP images (mean weighted K: MINIP 0.70, INSP sections 0.65, other image formats < or =0.48). Observers were most confident with EXP and MINIP images. EXP sections identified more disease than MINIP images (p<0.001). Correlations with pulmonary function tests were similar for each image format.

CONCLUSION

The HRCT changes of small airways disease are enhanced with image postprocessing. MINIP images are associated with increased observer confidence and agreement as compared with HRCT alone.

Acute respiratory distress syndrome: CT abnormalities at long-term follow-up

PURPOSE

To document abnormalities at computed tomography (CT) in adult survivors of acute respiratory distress syndrome (ARDS), to determine the relationships between CT patients during the acute phase and at follow-up, and to assess the effects of mechanical ventilation on the development of CT abnormalities.

MATERIALS AND METHODS

Thin-section CT scans were obtained during the acute illness and at follow-up in 27 patients with ARDS. The extent and distribution of individual CT patterns were independently analyzed.

RESULTS

At follow-up CT, a reticular pattern was the most prevalent (23 patients [85%]) and extensive CT abnormality, with a striking anterior distribution (more anterior distribution than posterior distribution, P < .001). A reticular pattern at follow-up was inversely correlated with the extent of intense parenchymal opacification on scans obtained during the acute illness (Spearman r = -0.26; P < .001). The extent of a reticular pattern at follow-up CT was independently related to the total duration of mechanical ventilation (P = .02) but was most strongly related to the duration of pressure-controlled inverse-ratio ventilation (P < .001).

CONCLUSION

A reticular pattern, with a striking anterior distribution, is a frequent finding of follow-up CT in ARDS survivors and is most strongly related to the duration of pressure-controlled inverse-ratio ventilation.