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J R van Dellen

Publications and source records attributed to J R van Dellen.

At least 19 recordsLinked to original sources
PubMed2003

Delayed postoperative intracerebral abscess caused by Proprionibacterium acnes: case report and review of the literature.

A case of delayed intracerebral abscess due to Proprionibacterium acnes (P. acnes), 18 months after an uneventful excision of a parasagittal haemangiopericytoma in a 61-year-old female is reported. This is highly unusual as cerebral abscess by P. acnes is rare and it occurred so late postoperatively in the absence of known risk factors. We propose the inclusion of cerebral abscess by P. acnes in the differential diagnosis of lesions that mimic tumour recurrences, after clean craniotomies.

Brain Abscess↗
PubMed2003

Genetic vulnerability following traumatic brain injury: the role of apolipoprotein E.

Apolipoprotein E (APOE) is thought to be responsible for the transportation of lipids within the brain, maintaining structural integrity of the microtubule within the neurone, and assisting with neural transmission. Possession of the APOE epsilon4 allele has also been shown to influence neuropathological findings in patients who die from traumatic brain injury, including the accumulation of amyloid beta protein. Previous clinical studies reporting varying outcome severities of traumatic brain injury, including cognitive and functional recovery, all support the notion that APOE epsilon4 allele possession is associated with an unfavourable outcome. Evidence from experimental and clinical brain injury studies confirms that APOE plays an important role in the response of the brain to injury.

Alleles↗
PubMed2001

Craniotomy improves outcomes for cranial subdural empyemas: computed tomography-era experience with 699 patients.

OBJECTIVE: Uncertainty regarding the best surgical management for subdural empyemas (SDEs) continues. Our unit has considered craniotomy the preferred method of surgical drainage for all cranial SDEs since 1988. We performed an analysis of our previously published, computed tomography-era, experience with 699 patients. METHODS: Two analyses of the database (1983-1997) were performed. First, analysis of the periods from 1983 to 1987 and from 1988 to 1997 was performed. Second, analysis of the composite database was performed. Outcomes were compared for possible outcome predictors by univariate analysis. Multivariate analysis was used to identify variables that contributed independently to outcomes, using stepwise discriminant analysis. RESULTS: Significant correlations between the analyzed periods with respect to outcome and type of surgery (P = 0.001) were noted. Analysis of the entire database (1983-1997) revealed a significant relationship between outcome and surgery type (P = 0.05). Pairwise comparison of limited procedures such as burr holes or craniectomies with wide-exposure surgical procedures such as primary craniotomies or procedures proceeding to full craniotomies indicated significant correlation with outcomes (P = 0.027). Reoperation and morbidity rates were increased with limited procedures. Stepwise discriminant analyses revealed that the type of surgery was correlated with outcomes (P = 0.0008, partial r(2) = 0.034). CONCLUSION: Craniotomy was determined to be the surgical procedure of choice for treatment of cranial SDEs, allowing complete evacuation of the pus and, more importantly, decompressing the underlying cerebral hemisphere. Limited procedures such as burr holes or craniectomies may be performed for patients in septic shock, for patients with parafalcine empyemas, or for children with SDEs secondary to meningitis.

Craniotomy↗
PubMed2000

Role of cerebrospinal fluid shunting for human immunodeficiency virus-positive patients with tuberculous meningitis and hydrocephalus.

OBJECTIVE: Tuberculous meningitis (TBM) and its complications continue to have devastating neurological consequences for patients. Budgetary constraints, especially in developing countries, have made it necessary to select patients for shunting who are likely to experience good recoveries. To date, the value of cerebrospinal fluid shunting for human immunodeficiency virus (HIV)-positive patients with TBM has not been clearly established. METHODS: Thirty patients with TBM and hydrocephalus were prospectively evaluated. Coincidentally, one-half of the patients were HIV-positive. All patients underwent uniform treatment, including ventriculoperitoneal shunt placement and antituberculosis treatment. CD4 counts were measured for all patients. Outcomes were assessed at 1 month. RESULTS: No complications related to shunt insertion were noted. The HIV-positive group fared poorly (death, 66.7%; poor outcome, 64.7%), compared with the HIV-negative group (death, 26.7%; poor outcome, 30.8%). Despite cerebrospinal fluid shunting, no patient in the HIV-positive group experienced a good recovery (Glasgow Outcome Scale score of 5). This is in contrast to the six patients (40%) in the HIV-negative group who, with the same treatment, experienced good recoveries (Glasgow Outcome Scale scores of 5) at discharge (P<0.14). No patient (either HIV-positive or HIV-negative) who presented in TBM Grade 4 survived, whereas no HIV-positive patient who presented in TBM Grade 3 survived. A significant relationship was noted between CD4 counts and patient outcomes (P<0.031). CONCLUSION: In the absence of obvious clinical benefit, HIV-positive patients with TBM should undergo a trial of ventricular or lumbar cerebrospinal fluid drainage, and only those who exhibit significant neurological improvement should proceed to shunt surgery.

AIDS-Related Opportunistic Infections↗
PubMed2000

Cerebral blood flow changes in rhinogenic subdural empyema and the role of hyperaemia in brain swelling.

BACKGROUND: Previous studies have demonstrated that rhinogenic subdural empyema (SDE) generally has a good prognosis. Most patients are admitted with an altered level of consciousness or significant neurological deficit, but eventually have a good outcome. It is well known that intra-operative brain swelling may occur with subdural empyema. OBJECTIVE: To define cerebral blood flow (CBF) dynamics and determine the role of cerebral hyperaemia, if any, in intracranial SDE. METHODS: CBF dynamics were assessed in five patients (mean age 13.2 +/- 2.2 years) with unilateral rhinogenic convexity SDE documented on computer tomography (CT). Regional cortical blood flow (rCBF) was measured using a thermo-coupled sensor placed on the cortex at the time of surgery. Dynamic CT scans were performed to assess cerebral blood volume (CBV) quantitatively, while transcranial Doppler ultrasonography (TCD) was used to measure cerebral blood flow velocities (CBF velocities) both pre- and post-operatively for 21 days. The opposite 'normal' hemisphere served as a control for each patient. RESULTS: Post-operative rCBF and CBF velocities in the pathological hemisphere progressively increased to plateau at 96 hours. Cerebral blood volume was increased bilaterally, but to a greater extent in the pathological hemisphere and more so in grey than white matter. These haemodynamic changes, though clinically significant did not reach statistical significance (p>0.05). CONCLUSION: Our results suggest that the accompanying brain swelling in rhinogenic SDE is a complex event, with reactive cerebral hyperaemia possibly playing neuroprotective role. Furthermore, unilateral convexity empyema causes bilateral cerebral haemodynamic changes. Future studies are necessary to define the aetiology of brain swelling in intracranial SDE.

Adolescent↗
PubMed1999

Intracranial subdural empyemas in the era of computed tomography: a review of 699 cases.

OBJECTIVE: Intracranial empyemas are the most common form of intracranial suppuration seen in our unit and, despite modern antibiotic therapy and advanced neurosurgical and imaging facilities, these pus collections remain a formidable challenge, often resulting in significant morbidity and death. We present an analysis of our 15-year experience with this condition in the era of computed tomography. METHODS: A retrospective analysis of 4623 patients admitted with intracranial sepsis during a 15-year period (1983-1997) identified 699 patients with intracranial subdural empyemas. The inpatient notes for these patients were analyzed with respect to clinical, radiological, bacteriological, surgical, and outcome data. Statistical analyses were performed. RESULTS: The 699 intracranial subdural empyemas accounted for 15% of all admissions for intracranial sepsis during the study period. Young male patients in the second or third decade of life were most commonly affected (62%), and the mean age was 14.65+/-12.2 years. Almost all patients (96%) underwent surgery. Eighty-two percent of patients experienced good outcomes (Glasgow Outcome Scale scores of 4 or 5). A morbidity rate of 25.9% (including postoperative seizures) was noted, and 85 patients died (mortality rate, 12.2%). CONCLUSION: Intracranial subdural empyema, which is a neurosurgical emergency, is rapidly fatal if not recognized early and managed promptly. Early surgical drainage, simultaneous eradication of the primary source of sepsis, and intravenous administration of high doses of appropriate antibiotic agents represent the mainstays of treatment.

Adolescent↗
PubMed1999

Cranial extradural empyema in the era of computed tomography: a review of 82 cases.

OBJECTIVE: Intracranial suppurative disorders (abscesses and empyemas) continue to be common neurosurgical emergencies in South Africa. Cranial extradural empyema (EDE) occurs less frequently than its subdural counterpart but remains a potentially devastating disease process. We present our 15-year experience with this condition in the era of computed tomography. METHODS: Of the 4623 patients with intracranial sepsis who were admitted to the neurosurgical unit at Wentworth Hospital (Durban, South Africa) during a 15-year period (1983-1997), 76 patients with EDEs were identified. An additional six patients who were identified from our outpatient records were treated nonsurgically. Analyses were performed with respect to clinical, radiological, bacteriological, surgical, and outcome data. All information for this study was obtained from the computerized databank for the unit. Statistical analyses of the related pre- and postoperative clinical data were performed. RESULTS: The 76 patients with EDEs accounted for 1.6% of the total number of patients admitted for treatment of intracranial sepsis during the study period. Thirteen patients (15.8%) had infratentorial pus collections. Male patients predominated by a ratio of 2:1, and 66 patients were between the ages of 6 and 20 years (mean age, 16.56+/-9.87 yr). The origins of the sepsis were paranasal sinusitis for 53 patients (64.6%), mastoiditis for 16 patients, trauma for 5 patients, dental caries for 1 patient, and miscellaneous causes for 7 patients. The most common clinical presenting features were fever, neck stiffness, and periorbital edema. Surgery was performed in the form of burrholes for 21 patients, small craniectomies for 39 patients, and craniotomies for 5 patients. The additional five patients, while having drainage of their infected paranasal sinuses, had simultaneous drainage of their extradural pus collections by the ear, nose, and throat surgeon. The majority of patients (81 patients) experienced good outcomes (Glasgow Outcome Scale scores of 4 or 5). A single patient died after surgery (mortality rate, 1.22%). CONCLUSION: EDEs occur less frequently than subdural empyemas and are associated with better prognoses. Surgical drainage (burrholes), simultaneous eradication of the source of sepsis, and high-dose intravenous antibiotic therapy remain the mainstays of treatment. Selective nonsurgical management of small EDEs is possible, provided the source of sepsis is surgically eradicated. It is our opinion that EDE is a disease that should be managed without morbidity or death.

Adolescent↗
PubMed1998

Traumatic brain contusions: a clinical role for the kinin antagonist CP-0127.

Focal cerebral contusions can be dynamic and expansive, leading to delayed neurological deterioration. Due to the high mortality associated with such cerebral contusions, our standard practice had evolved into evacuating contusions in patients who had a deterioration in level of consciousness, lesions > 30 cc and CT suggestion of raised ICP. Experimental brain edema studies have implicated kinins in causing 2 degrees brain swelling. CP-0127 (Bradycor), a specific bradykinin antagonist, has been found to reduce cerebral edema in a cold lesion model in rats. In a randomized, single blind pilot study, a 7 day infusion of CP-0127 (3.0 micrograms/kg/min) was compared to placebo in patients with focal cerebral contusions presenting within 24-96 hours of closed head injury with an initial GCS 9-14. The ICP, GCS, and vital signs were monitored hourly. The total lesion burden (TLB) was measured on serial CT scans. There were no differences in age, baseline GCS, TLB, initial ICP, or laboratory findings between the two groups (n = 20). The mean (+/- s.d.) rise in peak ICP from baseline was greater in the placebo group than with CP-0127 (21.9 +/- 4.7 vs 9.5 +/- 2.0, P = 0.018). In addition, the mean reduction in GCS in the placebo group was significantly greater than in the CP-0127 group (4 +/- 1.0 vs 0.6 +/- 0.4, P = 0.002). Significantly raised ICP and clinically significant neurological deterioration occurred in 7/9 patients on placebo (77%) and only in 1 patient (9%; n = 11) on CP-0127, mandating surgery (P = 0.005). There were no adverse drug reactions, significant changes in vital signs or variations in the laboratory values. The cerebral perfusion pressure was adequately maintained in all patients irrespective of therapy. These preliminary results with CP-0127 provide supporting evidence that the kinin-kallikrein system could be involved in cerebral edema. In this study, treatment with CP-0127 appeared to alter the natural history of traumatic brain contusions by preventing the 2 degrees brain swelling. In addition, CP-0127 obviated the need for surgery in the majority of treated patients. CP-0127 could act on the cerebral vasculature to limit dys-autoregulation and brain swelling or on the blood brain barrier to reduce cerebral edema.

Adult↗
PubMed1997

The effect of changes in barometric pressure on the risk of rupture of intracranial aneurysms.

Several meteorological variables have been linked with an altered incidence of cerebrovascular disease. In particular, we had noticed that, following abrupt changes in weather, patients with aneurysmal subarachnoid haemorrhage (SAH) often presented in groups. This study was undertaken to determine whether changes in barometric pressure would be an important factor. A retrospective analysis of a two year period was carried out. Daily mean, peak and trough atmospheric pressures had been recorded independently by a weather bureau. Of the 157 patients with SAH due to a berry aneurysm, confirmed by CT and angiography, 60 were entered into the study. Patients residing outside the weather bureau region (n = 86), or where there was uncertainty of their day of ictus (n = 11), were excluded. Daily peak to trough pressure changes and mean monthly pressure fluctuations showed no association with an increased risk of SAH. However, a significant relationship between the incidence of onset of symptoms indicative of a rupture of the aneurysm and a change in barometric mean pressure (BMP) of > 10 hectapascals from the previous day was found (p = 0.0247). The calculated odds ratio of sustaining a SAH with this associated BMP change was therefore 2.7 times with a risk of 1-13 times at a 95% confidence level (p = 0.035).

Aneurysm, Ruptured↗
PubMed1997

Cerebellar abscess: the significance of cerebrospinal fluid diversion.

OBJECTIVE: Cerebellar abscesses that are often ominously silent have a significant mortality. Sudden total occlusion of cerebrospinal fluid (CSF) pathways makes an aggressive surgical approach mandatory. Our neurosurgical unit at Wentworth Hospital, Durban, South Africa, prospectively instituted a protocol for patients with cerebellar abscesses with reference to CSF diversion with the aim of improving outcome. Our 13-year experience with this approach to cerebellar abscesses is presented. METHODS: Since 1983, patients with cerebellar abscesses have been managed according to a standard protocol. In 1987, a policy of aggressive CSF diversion was prospectively instituted. This involved immediate CSF diversion in any patient with over or incipient hydrocephalus, even if fully conscious. The associated hydrocephalus was diagnosed on initial computed tomographic scans. CSF diversion was performed by means of a ventricular drain, inserted in the reception area under local anesthesia. The period from January 1983 to December 1995 was analyzed, and the impact of aggressive CSF diversion on patient outcome was evaluated. RESULTS: Seventy-seven patients with cerebellar abscesses during the 13-year period under review were studied. Thirty-four patients were treated before the introduction of the policy of aggressive CSF diversion. Of these patients, 10 died, resulting in a mortality of 29% and a morbidity of 21%. Forty-three patients were treated after the institution of the new policy of CSF diversion. Of these patients, five died, resulting in a mortality rate of 11.6% and a morbidity rate of 14%. CONCLUSION: Although surgical drainage of a cerebellar abscess and eradication of the primary septic source and appropriate antibiotic coverage are necessary, the management of hydrocephalus, or even incipient hydrocephalus, is of paramount importance.

Adolescent↗
PubMed1997

Infratentorial empyema: analysis of 22 cases.

OBJECTIVE: Infratentorial empyema is an uncommon form of intracranial suppuration that is usually secondary to neglected otogenic infection. The diagnosis is frequently delayed and often confused with that of meningitis. The associated mortality is distressingly high, yet it has, as a clinical entity, received scant attention in the literature. We present a 13-year experience of this condition. PATIENTS AND METHODS: From a retrospective analysis of 3865 patients with intracranial suppuration during a 13-year period, 22 patients with infratentorial empyema were identified. The inpatient notes for these patients were analyzed with reference to clinical, radiological, bacteriological, operative, and outcome data. RESULTS: Twenty-two patients with infratentorial empyema accounted for 0.6% of admissions caused by intracranial suppuration during the study period. Of these 22 empyemas, 13 were subdural and 9 epidural. Hydrocephalus was present in 17 (77.3%). Except for two epidural empyemas that did not warrant neurosurgical intervention, all patients underwent standard surgical management (wide posterior fossa craniectomy). Nineteen underwent mastoidectomy because the source of infection was otogenic. Concomitant and persistent hydrocephalus was treated aggressively. Five patients died (mortality rate of 22.7%). All fatalities had subdural empyemas, and all three patients with cerebellopontine angle extension of subdural purulent collections died. CONCLUSION: Although rare, infratentorial empyema, especially when subdural, is a lethal disease. Cerebellopontine angle extension of pus was a particularly ominous sign in our experience. Early surgical drainage via wide posterior fossa craniectomy, aggressive treatment of associated hydrocephalus, eradication of the primary source of sepsis, and, finally, intravenous high dosage of appropriate antibiotics form the mainstay of treatment.

Adolescent↗
PubMed1997

Benefits to a regional neurosurgical unit following the introduction of a decentralised imaging facility.

OBJECTIVE: To determine whether the establishment of a peripheral computed tomography (CT) facility has an influence on the central referral neurosurgical unit, and particularly whether unnecessary referrals are avoided. DESIGN: The outpatient records of all patients referred from Umtata General Hospital (UGH) to the neurosurgical unit at Wentworth Hospital, Durban, were retrospectively analysed over a 4-year period--2 years before and 2 after the introduction of CT facilities at UGH. SETTING: Wentworth Hospital, Durban, which houses the sole neurosurgical referral centre for the region. PATIENTS: Eight hundred and forty patients were referred to the neurosurgical unit from UGH during the 4-year study period--July 1990 to June 1994. MAIN OUTCOME MEASURES: 1. The number of referrals to the neurosurgical unit before and after introduction of peripheral CT facilities at UGH. 2. The admission rate of the above referrals during the same periods, indicating appropriate referrals. RESULTS: 1. There were 536 patients referred from UGH to the neurosurgical unit over a 2-year period before the introduction of peripheral CT facilities, and 304 patients during the subsequent 2-year period after introduction of CT facilities at UGH. This represented a 43.3% decrease in patient referrals during a period in which referrals from all other areas increased by 2.6%. 2. The admission rate of patients (indicating appropriate referrals) being referred from UGH increased from 46.3% before CT facilities to 79.9% after the introduction of peripheral CT facilities. The admission rate of patients from other areas, excluding UGH, during the same periods, decreased from 50.3% to 46.4%. CONCLUSION: This audit reveals that following the introduction of CT facilities at UGH, the number of referrals to Wentworth Hospital's neurosurgical unit decreased by almost half (43.3%). Furthermore, the patients referred after introduction of the peripheral CT facility were more likely to be appropriate referrals (79.9%) than before (46.4%). Therefore, the provision of CT facilities at peripheral hospitals may effectively serve to exclude those patients who would otherwise be referred unnecessarily, and enable earlier referral of those patients who require urgent care at a tertiary neurosurgical unit.

Equipment and Supplies, Hospital↗
PubMed1995

A clinicopathological study of collagen sponge as a dural graft in neurosurgery.

There is frequently a need for dural grafts to cover defects resulting from retraction, shrinkage, or excision following neurosurgical procedures. Several materials have been evaluated both experimentally and clinically, and then discarded. Collagen, in its various forms, continues to be an area of intense interest. In this study the authors examined the suitability of collagen sponge to effect dural repair. In a 5-year clinical study 102 collagen sponge implants were examined macroscopically and histologically. Graft encapsulation, neomembrane formation, delayed hemorrhage, and foreign body reactions were not found. The porous nature of the collagen sponge encouraged fibroblastic ingrowth and dural repair. Meningocerebral adhesions were present in 11 patients, all of whom had required significant cortical resection or had pia-arachnoid disruption during the initial surgery. Inflammatory cells were seen only in response to infection. Postoperative cerebrospinal fluid leaks developed in only three of 67 patients who underwent an intradural posterior fossa procedure. In a prospective arm of the study involving 459 patients, the wound infection rate using collagen sponge was 6.1%, which compared favorably (p = 0.67) with the 5.7% rate in a similar group of 637 patients in whom collagen sponge had not been used.

Cerebrospinal Fluid Otorrhea↗
PubMed1994

Operative sepsis in neurosurgery: a method of classifying surgical cases.

Neurosurgical operations have traditionally been classified along the lines of general surgical procedures. A prospective study, during an 18-month period, was undertaken in 2249 patients undergoing neurosurgical procedures to establish and evaluate a method of classifying surgical cases by the use of specific neurosurgical criteria. Patients were placed in one of five categories according to the level and type of contamination at the time of surgery. Infection included all abnormal wounds and was documented as deep when infection occurred beneath the galea (subgaleal pus, osteitis, abscess/empyema, ventriculomeningitis) and as superficial if only the scalp (including wound erythema) was involved. A statistically significant difference in the sepsis rate was found in the different categories (P < 0.0001). Of the 342 "dirty cases," 9.1% of patients developed further wound sepsis. Concomitant cerebrospinal fluid fistulae (44%), second operations (11.8%), and patients with penetrating injuries (9.2%) were the major factors implicated in sepsis in the "contaminated" category (9.7%). In the "clean contaminated" category, a sepsis rate of 6.8% was found. Prolonged surgery (longer than 4 hours) was also implicated in higher infection rates (13.4%). This study strongly supports the separation of patients who have foreign materials implanted (sepsis rate = 6.0%) from "clean" patients, essentially cases categorized as having no known risk factors that may affect sepsis, in whom a sepsis rate of 0.8% was found (P < 0.001). Importantly, surgery for the repair of so-called "clean" neural tube defects in neonates requires separate consideration. An infection rate of 14.8% existed in this subgroup. A uniform system of reporting wound abnormalities is also proposed.

Bacteriological Techniques↗
PubMed1994

Hyponatremic natriuretic syndrome in tuberculous meningitis: the probable role of atrial natriuretic peptide.

Hyponatremia has been reported in up to one third of patients with intracranial disease and has frequently been associated with tuberculous meningitis, often complicated by hydrocephalus. The lowered plasma sodium levels were previously attributed to the syndrome of inappropriate secretion of antidiuretic hormone. A controlled prospective study of 24 patients with tuberculous meningitis and hydrocephalus was carried out. Analyses of serum electrolytes and cerebrospinal fluid were performed. Plasma and cerebrospinal fluid levels of atrial natriuretic peptide (ANP) and antidiuretic hormone (ADH) were measured by radioimmunoassay. Fifteen patients were found to be hyponatremic (plasma sodium < 130 mmol/L) and ANP levels of 12 to 1,488 pg/ml were present (median, 26 pg/ml). The remaining 9 patients had normal plasma sodium values between 130 and 145 mmol/L, and in these, plasma ANP values varied between 12 and 21.7 pg/ml (median, 12 pg/ml). The difference between these two groups was not statistically significant. (Control values from patients undergoing myelography were established to range between 12 and 40 pg/ml; median, 14.4 pg/ml.) ANP levels were undetectable in the cerebrospinal fluid in all. Plasma ADH levels in the hyponatremic group were between 7 and 159 pg/ml (median, 40 pg/ml). In the normonatremic group, plasma ADH levels of 25 to 250 pg/ml (median, 29 pg/ml) were obtained. (The controls ranged between 3.6 and 35 pg/ml; median, 10.4 pg/ml). In the hyponatremic group, there was a moderate negative correlation (r = -0.683) between plasma ANP and plasma sodium (P = 0.02). No correlation between plasma ADH and plasma sodium was found (r = -0.168; P = 0.62).(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial Natriuretic Factor↗
PubMed1993

The role of contralateral ventricular dilatation following surgery for intracranial mass lesions.

Contralateral ventricular dilatation (CVD) has been described as an early indicator of tentorial herniation and has been associated with increased mortality and morbidity. Following surgery for supratentorial mass lesions, ipsilateral brain swelling often causes CVD. Drainage of CVD was performed in a series of 12 patients in whom no further lesion amenable to surgery was evident and after failure of other established methods of intracranial pressure (ICP) control. In 10 of the 12 patients the ICP was brought under control with a significant reduction in ICP (p < 0.05) when compared with predrainage ICP. Midline shift was reduced in seven patients. Therefore, following successful removal of intracranial mass lesions, patients who exhibit CVD should undergo drainage as an early measure.

Brain Edema↗