Posterior fossa subdural hygroma with supratentorial chronic subdural haematoma

Subdural haematoma mimics

A subdural haematoma (SDH) is a frequently encountered pathology seen on an emergency room computed tomography (CT) head scan. An extra-axial crescentic density along the convexity of the brain or within the interhemispheric fissure is generally thought to represent a SDH; however, SDH mimics are known to occur in nature, and can be broadly classified under the subcategories of normal anatomy, artefacts, tumour, inflammation, infection, ischaemia, trauma, and iatrogenic. Understanding the typical characteristics of a SDH, knowledge of normal anatomy, close inspection of the morphology of the subdural process, changes to the adjacent structures, and rigorous attention to clinical details may reveal subtle clues that distinguish a true SDH from a mimic. This is crucial in appropriately directing clinical management. This review amalgamates most of the rare subdural processes that have been reported to mimic SDH, and discusses the imaging and clinical features that help to differentiate between them. This topic is highly valuable for radiology trainees, general radiologists, and emergency room physicians, and may serve as a refresher for the practising neuroradiologist.

Case Report: Acute obstructive hydrocephalus associated with infratentorial extra-axial fluid collection following foramen magnum decompression and durotomy for Chiari malformation type I

Acute obstructive hydrocephalus due to infratentorial extra-axial fluid collection (EAFC) is an extremely rare complication of foramen magnum decompression (FMD) and durotomy for Chiari malformation type I. Presence of infratentorial  EAFC invariably causes obstruction at the level of the fourth ventricle or aqueduct of Silvius, thereby indicating its definitive role in hydrocephalus. Pathogenesis of EAFC is said to be a local arachnoid tear as a result of durotomy, as this complication is not described in FMD without durotomy. Controversy exists in management. Usually EAFC is said to resolve with conservative management; so hydrocephalus doesn’t require treatment. However, in this case EAFC was progressive and ventriculo-peritoneal shunting (VPS) was needed for managing progressive and symptomatic hydrocephalus.

Delayed posttraumatic unilateral occipital epidural hygroma in early childhood

An extremely rare case of posttraumatic epidural hygroma in the left occipital supratentorial and infratentorial region is reported. A year and five months old child was admitted to the Clinic of Neurosurgery with sustained occipital head injury. She presented with drowsiness and vomiting due to intracranial hypertension. Initial computed tomography scan revealed left-sided fracture of the squamous part of the occipital bone without associated traumatic changes to the brain. A second spiral computed tomography scan was obtained two days later because of persisting symptoms of increased intracranial pressure. It demonstrated a newly formed left-sided epidural hygroma adjacent to the skull fracture in the left supratentorial and infratentorial occipital region. The case is discussed with emphasis on the mechanism of formation of epidural hygroma and an attempt has been made to outline the major predisposing factors leading to the development of this traumatic disease. Necessity for computed tomography follow-up is pointed out in order to diagnose delayed posttraumatic hygromas. The recommended surgical approach should include craniotomy centered at the site of the epidural hygroma and obligatory dural elevation by means of traction sutures to eliminate the posttraumatic epidural cavity.

Symptomatic posterior fossa and supratentorial subdural hygromas as a rare complication following foramen magnum decompression for Chiari malformation Type I

Symptomatic subdural hygroma due to foramen magnum decompression for Chiari malformation Type I is extremely rare. The authors present their experience with 2 patients harboring such lesions and discuss treatment issues. They conclude that the possibility of subdural hygromas should be considered in all patients presenting with increased intracranial tension following foramen magnum decompression for Chiari malformation Type I. Immediate neuroimaging and appropriate surgical intervention provides a good outcome.

Surgical treatment outcomes in subdural effusion: a clinical study

OBJECTIVE

In this study, patients who underwent surgery due to subdural effusion were retrospectively analyzed. The location, depth and etiology of the subdural effusion, the surgical approach that was used and the recurrence rates were studied in these patients.

METHOD

A total of 32 patients who were followed up and treated for subdural effusion at the Neurosurgery Clinic of the Yüzüncü Yil University School of Medicine were included in the study; 18 (56%) of the patients were male and 14 (44%) were female. The surgical techniques applied were surgical burr hole drainage, repeated subdural transaxial puncture and subduroperitoneal shunt approaches. The patients were evaluated by computerized tomography of the brain in week 1 and in the third month after surgery. Recurrences were evaluated based on radiological findings and the clinical condition of the patients.

RESULT

The consciousness level of the patients was proportional to the mass effect of the subdural effusion. Lower recurrence rates were found in patients with a large midline shift resulting from the subdural effusion. In addition, recurrence rates were higher in patients with cerebral atrophy and lower protein content in the subdural effusion fluid. It was observed that these patients responded better to the subduroperitoneal shunt treatment.