Clinical analysis of nineteen patients with traumatic subdural hygromas. (65/76)

Nineteen patients with traumatic subdural hygroma (TSH) who were admitted between 1988 and 1992, were reviewed. Diagnosis of TSH was made by serial computerized tomography (CT) after initial head injury, and patients were followed for up to 19 months after head injury. The patients ranged in age from 53 to 91 years (mean 75.6 yrs). Fifteen patients were treated conservatively, and 4 patients underwent surgery. Patients had disturbance of consciousness (transient in 5 cases, persisting in 3 cases), headache (10 cases), vomiting (6 cases), and vertigo (2 cases). TSH began to develop within 24 hs in 10 patients after initial head injury, and in 13 (68%) of 19 patients, TSH was demonstrated within 72 hs after the initial head injury. Chronic subdural hematoma (CSH) developed in 5 (26%) of 19 patients and 2 patients underwent surgery. In 15 patients, who were treated conservatively, TSH disappeared in 10 patients, and decreased in 4 patients, but remained unchanged in 1 patient. Clinically, 11 patients improved. Three patients remained unchanged. One patient, who had cerebral contusion, died of pneumonia. In 4 patients, who underwent surgery, including 2 patients with CSH, TSH disappeared in all patients. Two patients improved, and 1 patient was unchanged. Another patient, who had cerebral contusion and normal pressure hydrocephalus, died. In general, clinical outcome was satisfactory, except for the patients who had accompanying parenchymal lesions before or after head injury. Surgical treatment was limited to the patients who had rapidly enlarging TSH and neurological deterioration.  (+info)

Coexisting subdural and intercostal haemangiomata. (66/76)

Haemangioma in the chest wall is a very rare entity, seldom described in the literature. We report the case of a 23 year old woman presenting with independent, cervical subdural and intercostal haemangiomata. She suffered several episodes of recurrent, self-limiting subdural haemorrhage before diagnosis was made by magnetic nuclear resonance, aortography and selective intercostal angiography. Surgical excision was performed in both locations with excellent results.  (+info)

Temporal fluctuations in coherence of brain waves. (67/76)

As a measure of dynamical structure, short-term fluctuations of coherence between 0.3 and 100 Hz in the electroencephalogram (EEG) of humans were studied from recordings made by chronic subdural macroelectrodes 5-10 mm apart, on temporal, frontal, and parietal lobes, and from intracranial probes deep in the temporal lobe, including the hippocampus, during sleep, alert, and seizure states. The time series of coherence between adjacent sites calculated every second or less often varies widely in stability over time; sometimes it is stable for half a minute or more. Within 2-min samples, coherence commonly fluctuates by a factor up to 2-3, in all bands, within the time scale of seconds to tens of seconds. The power spectrum of the time series of these fluctuations is broad, extending to 0.02 Hz or slower, and is weighted toward the slower frequencies; little power is faster than 0.5 Hz. Some records show conspicuous swings with a preferred duration of 5-15s, either irregularly or quasirhythmically with a broad peak around 0.1 Hz. Periodicity is not statistically significant in most records. In our sampling, we have not found a consistent difference between lobes of the brain, subdural and depth electrodes, or sleeping and waking states. Seizures generally raise the mean coherence in all frequencies and may reduce the fluctuations by a ceiling effect. The coherence time series of different bands is positively correlated (0.45 overall); significant nonindependence extends for at least two octaves. Coherence fluctuations are quite local; the time series of adjacent electrodes is correlated with that of the nearest neighbor pairs (10 mm) to a coefficient averaging approximately 0.4, falling to approximately 0.2 for neighbors-but-one (20 mm) and to < 0.1 for neighbors-but-two (30 mm). The evidence indicates fine structure in time and space, a dynamic and local determination of this measure of cooperativity. Widely separated frequencies tending to fluctuate together exclude independent oscillators as the general or usual basis of the EEG, although a few rhythms are well known under special conditions. Broad-band events may be the more usual generators. Loci only a few millimeters apart can fluctuate widely in seconds, either in parallel or independently. Scalp EEG coherence cannot be predicted from subdural or deep recordings, or vice versa, and intracortical microelectrodes show still greater coherence fluctuation in space and time. Widely used computations of chaos and dimensionality made upon data from scalp or even subdural or depth electrodes, even when reproducible in successive samples, cannot be considered representative of the brain or the given structure or brain state but only of the scale or view (receptive field) of the electrodes used. Relevant to the evolution of more complex brains, which is an outstanding fact of animal evolution, we believe that measures of cooperativity are likely to be among the dynamic features by which major evolutionary grades of brains differ.  (+info)

Relations among traumatic subdural lesions. (68/76)

Acute subdural hematoma (ASDH), chronic subdural hematoma (CSDH) and subdural hygroma (SDG) occur in the subdural space, usually after trauma. We tried to find a certain relationship among these three traumatic subdural lesions in 436 consecutive patients. We included all subdural lesions regardless of whether they were main or not. We evaluated the distribution, age incidence and interval from injury to diagnosis of these lesions, and the frequency of new subdural lesions in each lesion. ASDH constituted 68.6%, SDG 15.8%, and CSDH 15.6%, Age incidence of CSDH was similar to that of SDG, but differed from that of ASDH. Mean interval from injury to diagnosis was 0.4 days in ASDH, 13.4 days in SDG, and 51.6 days in CSDH. Focal brain injuries accompanied in 37.5% of ASDH, 5.8% of SDG, and no CSDH. In ASDH, 2 recurrent ASDHs, 17 SDGs and 9 CSDHs occurred. In SDG, 3 postoperative ASDHs and 8 CSDHs occurred. In CSDH, 2 postoperative ASDHs, 2 SDGs and 1 CSDH occurred. These results suggest that the origin of CSDH is not only ASDH, but also SDG in upto a half of cases. SDG is produced as an epiphenomenon by separation of the dural border cell layer when the potential subdural space is sufficient. A half of CSDHs may originate from ASDHs. ASDH may occur in CSDH by either a repeated trauma or surgery. Such transformation or development of new lesions is a function of a premorbid condition and the dynamics between the absorption capacity and expansile force of the lesion.  (+info)

Spinal subdural enhancement after suboccipital craniectomy. (69/76)

PURPOSE: To characterize transient intraspinal subdural enhancement (potentially mimicking the subarachnoid spread of tumor) seen on MR images in some children after suboccipital craniectomy for posterior fossa tumor resection. METHODS: Radiologic and medical records of 10 consecutive children who had MR imaging for spinal staging after resection of posterior fossa tumor during a 9-month period were reviewed retrospectively. In addition, one case with similar findings of intraspinal enhancement on spinal staging MR images obtained at another institution was included in the review. RESULTS: Intraspinal enhancement thought to be subdural was seen in four of 10 patients undergoing spinal staging MR imaging 6 to 12 days after surgery. In these four patients, MR studies 50 to 18 days later, without intervening treatment, showed resolution of the abnormal enhancement. A fifth patient (from another institution) with similar intraspinal enhancement underwent CT myelography 4 days later, which showed no subarachnoid lesions. No metastases have developed in any of these five patients during the 2.5- to 3.5-year follow-up period. conclusions: From analysis of the MR appearance and on the basis of prior myelographic experience, we suggest an extraarachnoid, probably subdural, location of this enhancement. Awareness of this phenomenon will reduce the rate of false-positive diagnoses of metastatic disease. Preoperative spinal staging should be considered for patients undergoing suboccipital craniectomy.  (+info)

Treatment of suprasellar arachnoid cyst--two case reports. (70/76)

A 10-month-old girl presented with mental retardation and enlarged head, and a 3-year-old girl presented with epilepsy, both due to suprasellar arachnoid cysts. Magnetic resonance imaging demonstrated the suprasellar arachnoid cyst and the relationship between the cyst and surrounding structures. The 10-month-old patient with accompanying hydrocephalus was treated by fenestration of the cyst wall into the basal cistern. Postoperatively, bilateral subdural effusion appeared and subdural-peritoneal shunting was required. Thereafter, she regained the ability to walk. Two years postoperatively, the cyst reenlarged but communication between the cyst and surrounding cisterns and her development was normal, so she has been followed conservatively. The 3-year-old patient presented without hydrocephalus and was treated by cyst-peritoneal shunting using a Codman-Medos programmable valve through craniotomy. Postoperatively, the cyst was reduced and there has been no recurrence for 2 years and 5 months. We consider that cyst-peritoneal shunting is the most effective treatment for suprasellar arachnoid cyst.  (+info)

Infected subdural effusion associated with resolving subdural hematoma--case report. (71/76)

A 70-year-old male presented with rapid neurological deterioration and fever 3 months after suffering a closed head trauma. He underwent craniotomy for possible subdural empyema based on computed tomography and clinical findings. Dural incision revealed an outer membrane typical of chronic subdural hematoma which covered a clear, yellowish fluid containing Campylobacter fetus. Histological examination confirmed the capsule of the hematoma, with a necrotic focus infiltrated by neutrophils. Administration of intravenous imipenem and topical tobramycin and cefalothin achieved total resolution of his neurological deficits. Development of the infected subdural effusion was probably secondary to bacterial infection in the pre-existing chronic subdural hematoma in the resolving stage. The presence of the hematoma capsule always carries the risk of development of an infectious focus.  (+info)

Brain abscess and subdural empyema. Factors influencing mortality and results of various surgical techniques. (72/76)

The authors review the results of various surgical techniques in relation to mortality and morbidity in 100 consecutive cases of brain abscess and subdural empyema. The mortality rate is the same with total excision and fractional drainage of brain abscesses, although in acute and subacute cases slight differences between both techniques are seen. In terms of morbidity, fractional drainage appears to be more favourable than total excision. The authors believe that factors other than surgical procedure influence mortality in cases of brain abscess and subdural empyema. These factors are defined in detail.  (+info)