Swyer James syndrome complicated by infectious bronchiolitis

Findings and interpretation:

• The left lung is hyperlucent and reduced in volume, and shows a paucity of blood vessels. The left main pulmonary artery is small in calibre when compared with the right main pulmonary artery.
• There is cylindrical and saccular bronchiectasis within the left lung, more prominent in the lower lobe and lingula. There is mucus plugging / impaction of the bronchiectatic peripheral bronchial tree in the left lower lobe.
• There are widespread, segmental centrilobular and branching opacities, showing a characteristic ‘tree-in-bud’ pattern, with a bilateral, multi-lobar distribution. There is also linear subsegmental consolidation in the right lung base.
• There are a few enlarged subcarinal and pre-carinal mediastinal lymph nodes, which are likely reactive.

Pertinent negative findings:

• No evidence of pleural effusion.

Incidental findings:

• There is a minimal degree of bilateral apical paraseptal and scattered centrilobular emphysematous change.
• There is a right adrenal lesion with low (<10HU) density, representing an adenoma.

The findings indicate structural changes in the left lung which are longstanding, most likely caused by prior repeated infections. The ‘tree-in-bud’ opacities signify bronchiolar disease, which is most likely of infectious etiology. 

Principal diagnosis:

Swyer-James syndrome complicated by active infectious bronchiolitis.

Differential diagnosis:

• Follicular bronchiolitis
• Endobronchial spread of TB
• Cystic fibrosis: unlikely as the distribution of disease and structural changes are not in keeping with this diagnosis

Management:

Alert referring physician of findings.

Recommend referral to respiratory medicine.

Recommend bronchoscopy and broncho-alveolar lavage to obtain material for culture and sensitivity.  

Chronic pancreatitis on background of ADPKD

Findings and interpretation:

CT:

• There is dystrophic, coarse calcification along the head and body of the pancreas. This has a somewhat linear configuration, following the main duct at the head and proximal aspect of the body of the pancreas. A plastic biliary stent has been placed into the CBD via the duodenum (ERCP).
• The pancreatic margins are indistinct with surrounding peri-pancreatic fat stranding, particularly around the head and uncinate process. This region of the pancreas shows relative hypo-enhancement. There is dilatation of the main duct at the body and tail of the pancreas past the area of calcification.
• There is moderate dilatation of the intra and extrahepatic bile ducts down to the level of the mid CBD as it enters the pancreatic parenchyma, at which point the duct becomes no longer visible.
• Both kidneys as well as the liver contain innumerable well defined hypodense non-enhancing lesions of varying sizes. There are innumerable well-defined hypodense lesions throughout the liver. These represent simple cysts.

MRCP:

• CT findings confirmed on MRI with all liver and kidney cysts showing high T2 signal consistent with fluid contents and thin walls.
• MRCP confirms moderate dilatation of the intra and extrahepatic bile ducts, and demonstrates a gradual tapering of the mid to distal CBD. The distal CBD lumen appears occluded and is not visible on MRCP.

Pertinent negative findings:

• All kidney and liver cysts are simple, with no soft tissue masses / thickened, enhancing septae.
• There are no pancreatic pseudocysts / collections.
• No portal vein thrombosis / peri-pancreatic arterial aneurysms.

Incidental findings:

• There is mild splenomegaly.

The findings represent acute on chronic inflammation of the pancreas, causing a likely inflammatory stricture in the distal CBD, which has led to biliary obstruction. This has occurred on a background of a congenital condition causing cyst formation in the kidneys and liver.

Principal diagnosis:

Acute on chronic pancreatitis complicated by inflammatory CBD stricture and biliary obstruction, in a patient with autosomal dominant polycystic kidney disease.

Differential diagnosis:

• Pancreatic findings:
• Main duct IPMN
• Malignant CBD stricture
• Liver findings: The cystic lesions may represent abscesses rather than simple cysts. However, the kidney findings make it much more likely that these are manifestations of ADPKD.

Management:

Inform referring physician of findings, specifically that the biliary stent inserted via ERCP is failing to drain the biliary system.  

Discussion at hepato-biliary MDT is recommended.

Diffuse Axonal Injury

Findings and interpretation:

CT:

• There are hyperdense foci at the periventricular white matter adjacent to the right lateral ventricle, as well as at the grey-white matter junction of both frontal lobes superiorly. These represent foci of haemorrhage.
• There is also hyperdensity within the posterior horn of the right lateral ventricle and the third ventricle.
• There is a crescent shaped hyperdense, extra-axial collection overlying the right parietal lobe, representing a subdural haematoma. This is causing mild effacement of the adjacent sulci.
• There is a fracture of the left mandibular condylar neck.

MRI:

• There are foci of hyperintensity on the T2 and FLAIR sequences, corresponding to the areas of hyperdensity visualised on the CT scan. There is also hyperintensity at the body and splenium of the corpus callosum, and extending into the right thalamus. These lesions show diffusion restriction with high signal on the DWI and low corresponding ADC values.
• The SWI sequence shows foci of blooming artefact at the same lesions and at the locations of hyperdensity demonstrated on CT. These foci are also seen at the right parietal lobe and both temporal lobes, mostly at the grey-white matter interface with some extension into the cortex.
• The extra-axial collection is hypointense on T2 and hyperintense on T1, indicating subacute blood products.

Pertinent negative findings:

• No intracranial herniation.
• No fractures of the skull / skull base.

The findings represent traumatic brain injury, resulting in parenchymal brain damage with resultant intraparenchymal and intraventricular haemorrhage, as well as an acute subdural haematoma. The distribution of the traumatic lesions points to high energy shearing forces as the likely mechanism of trauma.

Principal diagnosis:

Diffuse Axonal Injury

Differential diagnosis:

• Parenchymal contusions
• Cerebral amyloid angiopathy

Management:

Urgently inform referring physician of findings.

The management in these cases is mostly supportive.

Metastatic ovarian cancer

Findings and interpretation:

CT:

• The abdomen is markedly distended with a large amount of free fluid in the peritoneal cavity.
• There are multiple, ill-defined masses and nodules of heterogeneous density located along the peritoneal reflections and peritoneal lining, on the hepatic capsule in a sub-phrenic location as well as at Morrison’s pouch, in the greater omentum and lesser sac. The greater omentum is thickened with areas of soft tissue density.
• There are multiple enlarged peri and para-aortic lymph nodes at L2 and L3 levels.
• There is an ill-defined soft tissue mass in the pouch of Douglas.
• There is a mild left pleural effusion.

MRI:

• The left ovary is located in a retro-uterine position, and is enlarged in size (incongruously with the patient’s reproductive stage). It contains multiple cysts, some of which are larger than expected in a menopausal patient. There are also ill-defined, solid mass-like components which are isointense, and irregular thickening of the ovarian stroma, lying in the pouch of Douglas.
• The solid components of the enlarged left ovary are avidly enhancing on the post contrast sequences.

Pertinent negative findings:

• The right ovary is normal.
• No bony lesions suspicious for metastases are detected.

The findings represent pathology involving the peritoneum and left ovary. There is peritoneal and omental caking. This is most likely to be a malignant, metastatic process that is arising from the left ovary, which is transformed by a neoplastic process. There is subsequent spread to the draining retroperitoneal lymph nodes, as well as direct peritoneal spread.

Principal diagnosis:

Metastatic ovarian cancer with peritoneal carcinomatosis

Differential diagnosis:

• Abdominal and ovarian tuberculosis.

Management:

Alert the referring physician of the findings.

Recommend ultrasound guided biopsy of one of the peritoneal masses for tissue diagnosis.

Recommend referral to gynaecology MDT / referral to the appropriate tertiary centre for further management.

Lumbar chordoma

Findings and interpretation:

CT:

• There is a large, ill-defined, retroperitoneal mass which is centred at the lumbar spine. It is situated between the lumbar vertebral bodies posteriorly, and the aorta and IVC anteriorly; it extends into the left psoas muscle and encases the distal aorta and left common iliac artery.
• The mass is of low soft tissue density with a large central area of dense, dystrophic calcification.
• The mass involves the left mid-ureter with resultant obstruction and left sided hydronephrosis. The left common iliac vein enters the mass and appears occluded by it.
• There is a small nodule at the right lung base.

MRI:

• The mass is markedly hyperintense on the T2 weighted images and isointense on T1.
• There is significant mass effect exerted on the structures surrounding the mass, such at the aorta and left psoas muscle.

Pertinent negative findings:

• There is no infiltration of the dural space / spinal canal contents.
• The mass appears to spare the vertebral bodies, with minimal invasion of the adjacent structures.

Incidental findings:

• There are two benign appearing lesions in the lumbar vertebral bodies, likely haemangiomas.
• Degenerative disc disease at L5/S1.
• Prosthesis for erectile dysfunction in pelvis.

The findings represent a midline, retroperitoneal, neoplastic mass which is moderately aggressive. The lung nodule may represent a metastatic deposit.

Principal diagnosis:

Lumbar chordoma (the significantly high T2 signal makes this the most likely diagnosis).

Differential diagnosis:

• Retroperitoneal leiomyosarcoma
• Retroperitoneal fibrosis
• Retroperitoneal malignant fibrous histiocytoma
• Chondrosarcoma
• Fibrosarcoma
• Treated lymphoma

Management:

Recommend image guided tissue biopsy.

Refer to a tertiary spine centre for further management.

Generalised lymphatic anomaly

Findings and interpretation:

Radiograph:

• There is a large opacity projected over the left hemithorax and chest wall, with a large component extending beyond the normal contour of the chest wall. This gives the appearance of a large soft tissue mass of the chest wall.
• There is no distortion or involvement of the ribs adjacent to the mass.
• There is a nasogastric tube in situ, with the tip in satisfactory position.

MRI:

• There are multiple large multi-cystic masses at the right side of the neck, anterior chest wall superiorly, left axilla and overlying the entire left aspect of the chest wall.
• The cysts making up the masses are of variable size, giving a mixed macrocystic and microcystic picture. They show relatively homogeneous bright T2 signal with variable signal on T1 (some appear hyperintense while others are hypointense).
• At the neck, the mass appears to insinuate into the right anterior triangle, displacing the sternocleidomastoid muscle and carotid sheath posteriorly and the larynx/pharynx laterally. At the left chest wall, the mass insinuates around the latissimus dorsi and between pectoralis minor and major, causing displacement of the muscles.
• The post contrast images show enhancement of the thin cystic walls, as well as the septations.

Pertinent negative findings:

• There are no cystic structures visualised in the solid organs or bones.
• The masses do not appear to invade the surrounding structures.

Interpretation:

• The findings represent congenital cystic lesions. In the neck, these show the characteristic appearance of a lymphatic malformation, or cystic hygroma. The widespread distribution of the lesions indicates a generalised disorder.
• The presence of hyperintensity on the T1 fat saturated sequence indicates the presence of blood products and haemorrhage into some of the cysts.
• Lateral displacement of the cervical airways may cause respiratory compromise.

Principal diagnosis:

Generalised lymphatic anomaly.

Differential diagnosis:

• Branchial cleft cyst: however, this would be localized to the neck only.
• Congenital haemangiomas: however, the enhancement pattern and cystic nature of the mass makes this diagnosis unlikely.

Management:

• Alert referring physician.
• Recommend discussion at pediatric surgery MDT with regards to further management.
• Consultation with interventional radiology for the possibility of sclerotherapy.