Conservative management of complicated Rathke's cleft cyst mimicking pituitary apoplexy.

Summary: Complicated Rathke's cleft cyst (RCC) is a rare occurrence of symptomatic bleeding or growth of a previously asymptomatic (and often undiagnosed) intrasellar cyst derived from remnants of Rathke's pouch, situated on the midline between the adeno- and neurohypophysis. Symptoms may be identical to those of pituitary apoplexy: acute onset of headache, hypopituitarism, and neurological disturbances. Both syndromes may also exhibit a similar appearance of a large haemorrhagic sellar mass at initial radiological evaluation. We report on two patients who presented with headache and complete hypopituitarism. Based on the initial MRI, they were first diagnosed with pituitary apoplexy but managed conservatively with hormone therapy alone because of the absence of severe visual or neurological threat. Upon follow-up at 4 months, clinical evolution was good in both patients but their pituitary mass had not reduced in size and, after careful radiologic reviewing, was more indicative of a large midline complicated RCC. In conclusion, the diagnosis of complicated RCC is challenging because it can mimic pituitary apoplexy clinically, biologically, and radiologically. Clinicians should distinguish between the two entities using specific radiological signs or evolution of the mass at MRI if the patient does not undergo surgery. To our knowledge, we report conservative management of this rare condition for the first time, though it seems appropriate in the absence of neurological compromise or visual compression. Long-term follow-up is however mandatory. Learning points: Complicated Rathke's cleft cyst can mimic pituitary apoplexy, presenting with sudden onset of headache, hypopituitarism, and visual and neurological compromise in the most severe cases. At diagnosis, pituitary MRI may not be able to differentiate between the two entities, showing a large haemorrhagic mass inside the sella, with little or no normal pituitary tissue visible. Patients are often diagnosed with apoplexy at this stage and may undergo pituitary surgery. When surgery has not been performed initially in these patients, repeat imaging at 3-6 months is unchanged and does not show the expected involution usually seen after adenoma apoplexy. Conservative management with hormonal replacement seems a valid option in the absence of visual or neurological deficits that would require trans-sphenoidal surgery.

Defining pseudoprogression in glioblastoma multiforme.

BACKGROUND AND PURPOSE: Pseudoprogression is a frequent phenomenon observed since the introduction of postoperative therapy with radiotherapy and temozolomide (RT/TMZ) in glioblastoma multiforme (GBM) patients. However, the criteria defining pseudoprogression, its incidence, the time of occurrence and its impact on therapy and outcome remain poorly defined. METHODS: The objective of this study is to compare two sets of criteria (liberal and stringent), defining pseudoprogression, in a cohort of patients treated before and after the introduction of RT/TMZ in the standard postoperative treatment. This retrospective review includes 136 unselected and consecutively treated patients with pathologically diagnosed GBM. RESULTS: Pseudoprogression was observed in 10 (12%) cases applying the stringent criteria, and in 18 (23%) patients when using the liberal criteria, in the cohort treated with RT/TMZ. Pseudoprogression was observed in only one patient treated with RT alone. The median time to pseudoprogression was 4 weeks after the end of RT. Patients with pseudoprogression had a median survival time of 28 months, compared with 12 months for patients without pseudoprogression. CONCLUSIONS: The incidence of pseudoprogression after RT/TMZ strongly depends on the applied criteria. However, regardless of the stringency of the criteria, the impact on survival remains the same.

CT density measurement and H:H ratio are useful in diagnosing acute cerebral venous sinus thrombosis.

BACKGROUND AND PURPOSE: Brain CT is widely used to exclude or confirm acute cerebral venous sinus thrombosis. The purpose of this study was to assess the value of attenuation measurement and the H:H ratio on unenhanced brain CT scans in the diagnosis of acute cerebral venous sinus thrombosis. MATERIALS AND METHODS: This retrospective study evaluated 20 patients with acute cerebral venous sinus thrombosis and 20 age- and sex-matched control participants without thrombosis. Three experienced observers independently evaluated the unenhanced brain CT scan for the presence of cerebral venous sinus thrombosis and measured the attenuation in the dural sinuses. Interreader differences were examined, as well as densities and H:H ratio between patients with acute cerebral venous sinus thrombosis and control participants. RESULTS: A significant difference in the average sinus attenuation was found between patients with acute cerebral venous sinus thrombosis (73.9 ± 9.2 HU) and the control group (52.8 ± 6.7 HU; P < .0001). A similar difference was found for the H:H ratio (1.91 ± 0.32 vs 1.33 ± 0.12 in patients with and without cerebral venous sinus thrombosis, respectively; P < .0001). Optimal thresholds of 62 HU and 1.52 lead to accuracies of 95% for average sinus attenuation and 97.5% for the H:H ratio, respectively. CONCLUSIONS: Hyperattenuation and the H:H ratio in the dural sinuses on unenhanced brain CT scans have a high accuracy in the detection of acute cerebral venous sinus thrombosis.

Acute intrathecal haematoma following neuraxial anaesthesia: diagnostic delay after apparently normal radiological imaging.

We describe a case of intrathecal haematoma following combined spinal-epidural anaesthesia for caesarean section. The parturient was previously well with no risk factors for haematoma development. Surgical intervention was delayed, resulting in permanent neurological injury. Incorrect interpretation of clinical findings and magnetic resonance imaging contributed to the delay in definitive treatment. We discuss the difficulties in diagnosis, image interpretation and the need for a specialist opinion when abnormal neurological symptoms persist despite apparently normal imaging.

Staging of lung cancer. Do we need a diagnostic CT of the brain after an integrated PET/CT for the detection of brain metastases?

Brain CT has been recommended in staging of patients with lung cancer because of its usefulness in the detection of metastases. Purpose of this study is to examine if a diagnostic brain CT (CT,) can be obviated when an integrated PET/CT (PET/CT) is available. 87 consecutive patients underwent a diagnostic brain CT and a whole-body PET/CT within a period of 3 weeks to stage a known primary tumour. CT examinations were evaluated by two experienced neuroradiologists on the detection of brain lesions (benign and malignant). The results of PET/CT and CT reading were compared and both readings were compared with the clinical results. Statistical analysis was done by measuring sensitivity, specificity, PPV, NPV and accuracy. The relative accuracies were compared by a McNemar (exact) test for correlated proportions. Considering the CT, as standard of reference, sensitivity, specificity, PPV, NPV and accuracy for the brain CT of PET/CT (CT2) and PET/CT were respectively 83%, 96%, 77%, 97%, 94% and 69%, 98%, 90%, 95%, 94%. Considering the clinical diagnosis as standard of reference these figures were for CT1, CT2 and PET/CT respectively 80%, 100%, 100%, 96%, 96% and 66%, 95%, 77%, 93%, 90% and 66%, 97%, 83%, 93%, 91%. There was no statistical difference between CT1 and CT2. The comparison of the additional CT in PET/CT with a diagnostic CT of the brain did not yield a statistical difference in the detection of brain lesions despite the inferior quality of the CT component of PET/CT. A diagnostic brain CT can be obviated when a PET/CT is available.

Optic tract edema sign and craniopharyngiomas.

Two patients with craniopharyngioma presenting with the "optic tract edema sign" are described. This sign is seen in a majority of craniopharyngiomas and can be of help in the differentiation with other suprasellar masses such as pituitary adenomas, meningiomas, germinomas and lymphomas. Nevertheless it has to be emphasized that the sign is not absolute and can be seen now and then in these other tumors.

Unenhanced brain CT is useful to decide on further imaging in suspected venous sinus thrombosis.

AIM: To assess the value of unenhanced brain computed tomography (CT) in the diagnosis of cerebral venous sinus thrombosis (CVST). MATERIALS AND METHODS: Unenhanced brain CT images of 26 patients with proven CVST were mixed with 26 age and sex-matched images from patients without CVST. Four readers reviewed the 52 brain CT images and were asked to score the examinations for the absence or presence of CVST on a scale from 0 to 4. The mean density in the different venous sinuses was measured by one radiologist. RESULTS: The sensitivity of unenhanced brain CT for the diagnosis of CVST was 73%. There were no false-positive readings. A receiver-operating characteristic (ROC) analysis on these data resulted in an area under the curve of 0.86. Density measurements proved to be helpful, but could not detect all cases of CVST. CONCLUSION: Unenhanced brain CT is a valid initial radiological examination in the diagnosis of CVST. Due to the absence of false-positives in the present series, unenhanced CT can be used to decide whether further imaging with CT angiography or magnetic resonance angiography is required.

Persistent Trigeminal Artery Variant: MR Angiographic Demonstration. A Report of Two Cases.

A variant (PTAV) is the persistence after birth of the fetal carotid-basilar anastomosis between the internal carotid artery and a cerebellar artery. We describe two cases of a PTAV demonstrated on MR angiography. A comparison with a persistant trigeminal artery is made and an explanation of the extended Saltzman classification is given. These variants have only little clinical significance, but their recognition is crucial before surgical or interventional procedures or to understand paradoxical cerebellar lesions. MRA appears inferior to selective angiography in diagnosing these variants.

A 63-year-old man with peripheral facial nerve paralysis and a pulmonary lesion.

BACKGROUND: Occasionally, malignant neoplasms may cause peripheral facial nerve paralysis as a presenting symptom. CASE REPORT: A 63-year-old man was referred to the Emergency Department because of a peripheral facial nerve paralysis, lasting for 10 days. Initial diagnostic examinations revealed no apparent cause for this facial nerve paralysis. Chest X-ray, however, showed a suspicious tumoural mass, located in the right hilar region, as confirmed by CAT scan. The diagnosis of an advanced stage lung adenocarcinoma was finally confirmed by bronchial biopsy. MRI scanning showed diffuse brain metastases and revealed a pontine lesion as the most probable underlying cause of this case of peripheral facial nerve paralysis. Platin-based palliative chemotherapy was given, after an initial pancranial irradiation. RESULTS: According to the MRI findings, the pontine lesion was responsible for the peripheral facial nerve paralysis, as an initial presenting symptom in this case of lung adenocarcinoma. CONCLUSION: This clinical case of a peripheral facial nerve paralysis was caused by a pontine brain metastasis and illustrates a rather rare presenting symptom of metastatic lung cancer.

Angiographic confirmation of brain death after decompressive craniectomy for posttraumatic brain oedema.

In patients who underwent decompressive craniectomy for brain oedema, angiography for the assessment of brain death can show filling of the intracranial supratentorial arteries.This does not exclude brain death, provided circulatory arrest and absence of venous drainage are present.

Hypoplasia of L5 and wedging and pseudospondylolisthesis in patients with spondylolysis: study with MR imaging.

BACKGROUND AND PURPOSE: The association between L5 hypoplasia and bilateral spondylolysis was described earlier on conventional radiographs of the lumbar spine. The purpose of this study was to describe the findings on MR imaging in patients with hypoplasia of L5 and to correlate these findings with the presence of bilateral spondylolysis of L5. MATERIAL AND METHODS: We studied the MR images of 22 patients with hypoplasia and posterior wedging of L5 and with bilateral spondylolysis at L5. The anteroposterior diameter of L4, L5, and S1 were measured and compared. The degree of posterior wedging of L5 was calculated. The degree of anterolisthesis was determined. The intervertebral disks of L4-L5 and L5-S1 were studied. RESULTS: The mean difference between the anteroposterior diameter of L4 and L5 was 3.0 mm, or 8.8% shortening of L5 compared with L4. The mean difference between the anteroposterior diameter of L5 and S1 was 4.4 mm, or 12.3% shortening of L5 compared with S1. The mean percentage posterior wedging was 24.7%. In 13 patients, there was no anterior vertebral slipping. True anterolisthesis grade I was seen in 5 patients and anterolisthesis grade II in 4 patients. Diskarthrosis with disk dehydration of L4-L5 was seen in 20 of the 22 patients. CONCLUSIONS: It is confirmed that hypoplasia of L5 can simulate anterolisthesis. Hypoplasia of the vertebral body of L5 can predict the presence of bilateral spondylolysis.

Epidermoid cyst of the fourth ventricle: diffusion-weighted and flair MR imaging findings.

Fourth ventricle epidermoid cysts are rare lesions, arising from epithelial remnants at the time of neural tube closure. They are well-defined CT hypoattenuated masses that resemble CSF on all conventional MR imaging sequences. We present a case of a pathological proven less common fourth ventricle epidermoid cyst with special emphasis on the use of FLAIR and EPI-DW imaging sequences in the diagnosis.

Lacrimal gland and perioptic nerve lesions due to Langerhans cell histiocytosis (2007: 9b).

We report a patient presenting with bilateral lacrimal gland involvement and perioptic nerve sheath lesions due to Langerhans cell histiocytosis (LCH) invasion. LCH is a rare multisystemic disease characterized by a clonal proliferation of Langerhans cells. All organs may be involved with a clinical spectrum ranging from a solitary bone lesion to a severe life-threatening multisystem disease. Osteolytic orbital bone lesions with extension into the adjacent orbital soft tissues have been described. To our knowledge, lacrimal gland involvement has probably been described only once before. Perioptic nerve lesions are also very rare, having been described only three times before.