Chronic Subdural Fluid Collections Research Articles

3D-Printer-Assisted Patient-Specific Polymethyl Methacrylate Cranioplasty: A Case Series of 16 Consecutive Patients

To develop a novel 3D-printer-assisted method to fabricate patient-specific implants for cranioplasty and to demonstrate its feasibility and its use in 16 consecutive cases. We report on 16 consecutive patients who have undergone cranioplasty surgery for an extensive skull defect after decompressive surgery and in which the bone flap was not available. We present the workflow for the implant production using a 3D-printer-assisted molding technique. Preoperative, intraoperative, and postoperative data were analyzed/evaluated. Eleven out of our 16 patients (68.7%) presented with extensive hemispheric bone defects. Indication for initial craniotomy were traumatic brain injury (4; 25%), acute subdural hematoma (4; 25%), ischemic stroke (3; 18.8%), tumor (3; 18.8%), and ruptured aneurysm (2; 12.5%). Median (range) operation time was 121 (89-206) minutes.Median (range) intraoperative blood loss was 300(100-3300) mL. The mean (range) follow-up period is 6 (0-21) months. Complications occurred in 7 out of our 16 patients (43.8%), in 6 (37.5%) of which a reoperation was required to evacuate an extra-axial hematoma (3; 50%), for shunting of an epidural fluid collection (1; 16.7%), or for skin flap necrosis (1; 16.7%). One patient (16.7%) developed a chronic asymptomatic subdural fluid collection that was stable over the follow-up period. Our workflow to intraoperatively produce patient-specific implants in a timely manner to cover cranial defects proved to be feasible. The results are cosmetically appealing, and postoperative CT scans show well-fitting implants. As implantable printable substrates are already available, we aim to advance and certify 3D-printed patient-specific implants in the near future.

Schizencephaly Associated with Chronic Subdural Fluid Collection: Case Report

Schizencephaly is an uncommon congenital structural disorder of cerebral cortex caused by abnormal neuronal migration. Patients usually present with seizure disorders, hemiparesis, quadriparesis, cognitive deficits and mental troubles. Very rarely, schizencephaly is also associated with subdural fluid collection, and may present with mass effect. In this study we present a schizencephaly case with chronic subdural fluid collection. In our view, clefts may promote subdural fluid collection in schizencephaly patients and careful follow up of these patients is needed.

“Shaken baby syndrome” and forensic pathology: an uneasy interface

‘‘Shaken baby syndrome,’’ as it was once known, hasbecome a very contentious and hotly debated area in thefields of forensic pathology and medicine of infants andyoung children [1, 2]. Described by Caffey in the 1970s toencompass situations where intracranial injury was presentin the absence of external signs of head trauma, it wasbelieved to result from violent shaking of an infant [3].Infants and children under 2 years of age are thought to bethe most vulnerable as their heads are disproportionatelyheavy relative to their bodies, the neck muscles are weak,the brain is soft as many axons are unmyelinated, and thebase of the skull is flat [4, 5]. It has been asserted that thenature of the shaking is such that it should be recognized bythe perpetrator as likely to be harmful [5], i.e., it is notsomething that could happen during normal playfullyhandling.Classically infants may present with a hyperacuteencephalopathy (cervicomedullary syndrome) with acuterespiratory failure and severe cerebral edema due to brainstem injury, an acute encephalopathy with a depressedconscious state, fits, apnea, and hypotonia, with raisedintracranial pressure, bilateral subdural hemorrhages andretinal hemorrhages, a subacute non-encephalopathic statewith less severe brain injury and various combinations ofsubdural and retinal hemorrhages, rib fractures and bruising,or with a chronic state with isolated subdural hemorrhage,rapidly expanding head circumference, and signs of raisedintracranial pressure [6].In milder cases an infant or child may present withnonspecific features such as vomiting, poor feeding, leth-argy, and irritability. While some children will recover,survivors may have residual neurologic sequelae such asspasticity, seizures, cortical blindness, microencephaly,chronic subdural fluid collections, cerebral atrophy, andporencephalic cysts [5].In a lethal case argument exists as to whether the infantmay appear quite normal for a period of time (i.e., have a so-called ‘‘lucid interval’’), or may instead be immediatelysymptomatic [7]. Given the severity of the injury (i.e., theevent has resulted in death) and the rapidity with whichintracranialpressurehasbeenshowntoriseinanimalmodelsfollowing blunt trauma [8] the author considers it veryunlikely that an infant would be able to engage in normalactivities in an apparently unaffected manner after such aninsult. Death is believed to occur in approximately 15–38 %of cases and the findings at autopsy, as noted, include sub-dural hemorrhage that is usually bilateral, subarachnoidhemorrhage, and retinal hemorrhage. The subdural hemor-rhage tends to be maximal in the inter-hemispheric fissure,usually measures less than 5–10 ml on each side, and doesnot cause a mass effect [4, 5].However, the validity of the diagnostic criteria and theevidence for underlying mechanisms have been questioned[9–11]. A ‘‘unified hypothesis’’ was proposed in 2003 whichsuggested that subdural and retinal hemorrhages in infantswho had been shaken were due to hypoxia with brainswelling, rather than to blunt trauma [12]. This study has,however, been challenged [13] and it has been suggestedthat there were ‘‘serious flaws in the methodology’’ [14]. Aretrospective multicenter study of infants and young chil-dren with proven hypoxic brain injury in the absence oftrauma was certainly not able to demonstrate intracranialhemorrhage [15]. Similarly there has been little support for

Analysis of the subdural evacuating port system for the treatment of subacute and chronic subdural hematomas

The subdural evacuating port system (SEPS; Medtronic, Inc.) is a minimally invasive means of draining subacute or chronic subdural fluid collections. The purpose of this study was to examine a single institution's results with the SEPS. A retrospective chart review was undertaken for all patients who underwent SEPS drainage of subdural collections. Demographic and radiographic characteristics were evaluated. Both pre- and post-SEPS CT studies were analyzed to determine the volume of subdural collection and midline shift. Hospital charts were reviewed for SEPS output, and periprocedural complications were noted. were classified as a success (S) or failure (F) based on the need for further subdural drainage procedures. Groups were then compared to identify factors predictive of success. Results Eighty-five subdural collections were treated in 74 patients (unilateral collections in 63 patients and bilateral in 11). Sixty-three collections (74%) were successfully drained. In a comparison of the success and failure groups, there were no statistically significant differences (p < 0.05) in the mean age pre-SEPS, Glasgow Coma Scale score, presenting symptoms, underlying coagulopathy or use of anticoagulation/antiplatelet agents, laterality of SDH, pre-SEPS subdural volume or midline shift, or any of the measurements used to characterize SEPS placement. There were a greater number of male patients in the success group (45 [82%] of 55 patients vs 11 [58%] of 19 patients; p = 0.04). The only statistically significant (p < 0.05) factor predictive of success was the radiographic appearance of the subdural collection. More hypodense collections were successfully treated (32 [51%] of 63 collections vs 4 [18%] of 22 collections; p = 0.005), whereas mixed density collections were more likely to fail SEPS treatment (S: 11 [17%] of 63 collections vs F: 14 [64%] of 22 collections; p < 0.00001). In the success group, the percentage of the collection drained after SEPS was greater (S: 47.1 ± 32.8% vs F: 19.8 ± 28.2%; p = 0.001) and a larger output was drained (S: 190.7 ± 221.5 ml vs F: 60.2 ± 63.3 ml; p = 0.001). In the patients with available but delayed scans (≥ 30 days since SEPS placement), the residual subdural collection following successful SEPS evacuation was nearly identical to that remaining after open surgical evacuation in the failure group. In 2 cases (2.4% of total devices used), SEPS placement caused a new acute subdural component, necessitating emergency evacuation in 1 patient. The SEPS is a safe and effective treatment option for draining subacute and chronic SDHs. The system can be used quickly with local anesthesia only, making it ideal in elderly or sick patients who might not tolerate the physiological stress of a craniotomy under general anesthesia. Computed tomography is useful in predicting which subdural collections are most amenable to SEPS drainage. Specifically, hypodense subdural collections drain more effectively through an SEPS than do mixed density collections. Although significant bleeding after SEPS insertion was uncommon, 1 patient in the series required urgent surgical hematoma evacuation due to iatrogenic injury.

Effect of intracranial pressure on the diameter of the optic nerve sheath

The subarachnoid space around the optic nerve in the orbit can be visualized using T2-weighted MR imaging with the fat-saturation pulse sequence. The optic nerve sheath (ONS) diameter can be estimated by measuring the outer diameter of the subarachnoid space. Dilated ONS is associated with idiopathic intracranial hypertension and hydrocephalus, and is believed to reflect increased intracranial pressure (ICP). The relationship between dilated ONS and ICP is unclear because of the difficulty in obtaining noninvasive measurements of ICP. The authors investigated the relationship between subdural pressure measured at the time of surgery and ONS diameter measured on MR images in patients with chronic subdural fluid collection. Twelve patients underwent bur-hole craniostomy with continuous drainage for chronic subdural hematoma or hygroma in 2006. Orbital thin-slice fat-saturated MR images were obtained before and after surgery, and the ONS diameters were measured just behind the optic globe. Subdural pressure was measured using a manometer before opening of the dura mater. A significant correlation was found between the ONS diameter and the subdural pressure (correlation coefficient 0.879, p = 0.0036). The ONS diameter before surgery (6.1 +/- 0.7 mm) was significantly reduced after surgery (4.8 +/- 0.9 mm, p = 0.003; measurements are expressed as the mean +/- standard deviation). Increased ONS diameter measured on coronal orbital thin-slice fat-saturated T2-weighted MR images is a strong indicator of increased ICP, and helps to differentiate between passive subdural fluid collection due to brain atrophy and subdural hygroma with increased ICP.

Neurosurgical implications of osteogenesis imperfecta in children

Osteogenesis imperfecta (OI) is a rare genetic disorder characterized by disruption of normal collagen formation resulting in varying degrees of skeletal vulnerability, ligamentous laxity, and scleral discoloration. Children with OI may suffer from complex neurosurgical problems affecting the brain and spine. The authors sought to determine the neurosurgical implications of OI in a cohort of patients treated at a quaternary care center for pediatrics. The authors reviewed the case histories of 10 children with OI treated by the neurosurgical service at the Hospital for Sick Children in Toronto between January 1988 and March 2007. The cases of 4 of these children are highlighted in the article. The most common neurosurgical conditions encountered in this cohort included macrocephaly in 5 patients, subdural hematoma in 3 patients, epidural hematoma in 2 patients, and hydrocephalus in 3 patients. Basilar invagination and spinal fractures were observed in 20% of the cohort. Although some patients could be treated nonoperatively, several required craniotomy for clot evacuation, decompression, and spinal fixation for fracture or basilar invagination, and cerebrospinal fluid shunt insertion. Neurosurgical conditions affecting patients with OI include macrocephaly, the development of an acute intracranial hematoma after often minimal trauma, the development of chronic subdural fluid collections that may require drainage, hydrocephalus (both communicating and noncommunicating), basilar invagination, and subaxial spinal fractures. Surgery may be complicated in some children because of the underlying bone fragility and bleeding diathesis commonly observed in patients with OI.

Subdural-atrial and subdural-peritoneal shunting in infants with chronic subdural fluid collections

Background: In symptomatic infants with chronic subdural fluid collections a variety of treatment strategies, such as observation, repeated subdural tapping, external or internal subdural drainage, and craniotomy have been advocated. Until now, the ideal management for this etiologically heterogenous group of children seems controversial. Methods: The authors present their treatment with subdural-peritoneal and subdural-atrial shunts and the follow-up in 8 infants (mean age, 7 months) with bifrontal subdural hygromas and hematomas caused by different etiologic conditions. Results: Initially, all children were symptomatic, and repeated subdural taps showed no clinical and neuroradiologic benefit. Shunting resulted in disappearance of all clinical signs in all infants, with complete removal of the chronic subdural fluid collections in 6 cases and remarkable improvement in 2 cases. In all infants the shunt system was removed after disappearance of signs and decrease of fluid collections. As the only complication the shunt system had to be removed in 1 case on the fourth postoperative day because of infection without any further disadvantages. In none of the cases was a recurrence of the fluid collections seen during the follow-up. Conclusion: These results suggest that in infants with symptomatic chronic subdural fluid collections who fail to respond to repeated tapping, the early placement of an unilateral subdural-peritoneal shunt with a low pressure valve represents a safe, benign, and effective treatment option. J Pediatr Surg 35:1339-1343. Copyright © 2000 by W.B. Saunders Company.

Spontaneous intracranial hypotension

Purpose: To describe a patient with classic presentation of spontaneous intracranial hypotension and subsequent improvement with targeted epidural blood patch. Methods: Report of one case and review of the literature. Results: Examination of cerebrospinal fluid after lumbar puncture disclosed a reduced opening pressure, an increased level of protein, and lymphocytic pleocytosis. Magnetic resonance imaging of the brain with gadolinium showed diffuse enhancement of the pachymeninges, no evidence of leptomeningeal enhancement, and chronic subdural fluid collection. Radionuclide cisternography demonstrated reduced activity over the cerebral convexities, early accumulation of radiotracer in the urinary bladder, and direct evidence of leakage at the cervicothoracic junction (C 7-T 1). Clinical, laboratory, and radiologic features were consistent with the diagnosis of spontaneous intracranial hypotension. Therapy with a targeted epidural blood patch resulted in the rapid resolution of symptoms. Conclusions: In this report, we describe a classic case of spontaneous intracranial hypotension in a 63-year-old man with an initial presentation of postural headaches, blurred vision, pain in the left eye, diplopia on left gaze, and neck soreness.

Quantitative kinetic analysis of blood vessels in the outer membranes of chronic subdural hematomas.

Dynamic biologic modeling was used to calculate the transfer rate constant for gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) and capillary permeability in the outer membrane of chronic subdural hematomas and effusions. Following intravenous Gd-DTPA injection, Gd concentrations in the subdural fluid and in timed arterial blood samples were measured by ion-coupled plasma emission spectrometry in 53 chronic subdural hematomas and 18 chronic subdural effusions. The capillary surface area in outer membrane was assessed morphometrically. Transfer rate constants for subdural hematomas and subdural effusions were 12.4 +/- 1.0 and 20.6 +/- 1.7 (x 10(-4)min-1, respectively. Capillary permeabilities for subdural hematomas and subdural effusions were 16 +/- 1.2 and 19 +/- 3.7 ml.min-1(mm2/mm3)-1, respectively. The capillary surface areas for subdural hematomas and subdural effusions were 48 +/- 3 and 77 +/- 10 mm2/mm3, respectively. The high degree of infiltration of Gd into subdural effusions reflects the high capillary surface area in the outer membrane rather than greater permeability of individual capillaries. The value of transfer rate constant was correlated inversely with the duration of the chronic subdural fluid collection. Immature outer membrane has a high transfer rate constant which allows extravasation of plasma components into the subdural space, resulting in increasing volume of the subdural effusion. Delayed magnetic resonance imaging following Gd administration may be clinically useful for estimating the age of chronic subdural fluid accumulations.

A method for continuous external drainage in the management of infantile subdural collections.

There is no consensus on the management of infantile chronic subdural collections. Subdural tapping, craniotomy and removal of membranes, and shunting from the subdural space have all been used. We performed continuous external subdural drainage (CESD) as a step prior to subdural-peritoneal shunt placement in the management of infantile chronic subdural fluid collections. A lumbar drainage set was used for CESD. The catheter was placed in the subdural space through the anterior fontanel with a Touhy needle. This percutaneous technique seems an easy and safe method for CESD in infants with chronic subdural collections.

Intracerebral Hematoma after Evacuation of Chronic Subdural Fluid Collection

The authors encountered three cases of intracerebral hematoma (ICH) occurring early after surgery for chronic subdural fluid collection. A 54-year-old male complained of speech disturbance and facial weakness 22 hours after irrigation of a chronic subdural hematoma (CSH). Computed tomography scan showed an ICH beneath the previously removed CSH. His neurological deficit disappeared with conservative treatment. A 73-year-old male developed expressive aphasia 14 hours after surgery for chronic subdural hygroma. The patient was treated conservatively and the aphasia was still present 1 year after the ictus. A 3-month-old boy developed a left ICH and had a generalized convulsion 60 hours after irrigation of bilateral CSH. With conservative treatment there was no neurological deficit 1.5 months after the episode. Almost all of the reported ICH appeared in the subcortex just beneath a previously evacuated collection of subdural fluid. The symptoms were rapid deterioration of consciousness and focal neurological deficits developing soon after surgery. One possible mechanism of ICH is diapedesis through increased permeability of parenchymal blood vessels due to the sudden increase in cerebral blood flow after longstanding extracerebral fluid collection. The prognosis of this complication is poor. Therefore, subdural fluid should be removed slowly to avoid sudden decompression.

Factors affecting coagulation: fibrinolysis in chronic subdural fluid collections.

Plasminogen, alpha2-antiplasmin, fibrinogen, fibrin degradation products (FDP's), and hemoglobin were measured in the supernatant fluid of 25 chronic subdural hematomas and five chronic subdural hygromas. The 30 patients underwent pre- and postoperative computerized tomography. The hematomas were characterized by low fibrinogen and high fibrin degradation product concentrations. The hemoglobin content varied directly with the alpha2-antiplasmin, and inversely with the plasminogen. Four patients underwent reoperation for recurrences. The initial fluid from these cases was characterized by relatively high plasminogen and low alpha2-antiplasmin. The hygromas had no hemoglobin, and low fibrinogen, high FDP's, low alpha2-antiplasmin, and variable plasminogen levels. It is possible that those cases having the greatest capacity to produce plasmin (high plasminogen and low alpha2-antiplasmin) can produce more FDP's which in turn causes more rebleeding and an increased risk of reaccumulation of chronic subdural hematomas.

Simplified supplementary treatment of chronic subdural fluid collections.

Simplified supplementary treatment of chronic subdural fluid collections.

Roentgenologic signs of resolving subdural hematomas.

Subdural hematoma has been a recognized entity since the eighteenth century and possibly earlier (1). In spite of its long history, many questions concerning this condition remain unanswered. Among these is: Does a subdural hematoma ever undergo spontaneous resolution? Occasional reports (2–4) have appeared in the literature concerning subdural collections diagnosed by cerebral angiography or pneumography which subsequently cleared. The nature of these collections, however, whether cerebrospinal fluid or blood, has remained unknown. Cerebral atrophy may give the angiographic appearance of an acute subdural collection (5). Occlusion of several small branches of the middle cerebral artery may also simulate an acute subdural collection on the anteroposterior view. The purpose of the investigation to be reported here was to determine whether subdural hematomas ever regress spontaneously. It was not meant to offer a new mode of therapy for this condition. The patients were selected because of their good clinical condition. They were observed constantly and if, at any time, this had worsened, they would have been subjected immediately to surgery—burr holes and/or craniotomy. The clinical aspects of these cases will be included in another report. Case I: A 29-year-old man was well until two weeks prior to admission, when he first experienced frontal headaches and low back pain. He was drowsy upon entering the hospital and exhibited a left central facial palsy and slight nuchal rigidity. The left upper extremity was a little weak, the deep tendon reflexes were increased on the left, and the superficial abdominal reflexes were absent on that side. Lumbar puncture revealed xanthochromic fluid. On the seventh hospital day a left carotid angiogram (Fig. 1) demonstrated an acute subdural collection. The following day a left parietal burr hole was made. A 20-gauge needle was inserted through the dura, 0.4 c.c, of brownish-red material resembling old blood was aspirated, and the wound closed. The benzidine test of this fluid was positive. The patient was then followed with serial angiograms. He became alert, coherent, and oriented, and his neurological deficit disappeared. After eight weeks all angiographic signs of subdural hematoma had vanished. Case II: A middle-aged man was confused, disoriented, and drowsy upon admission to the hospital. No history could be obtained. Physical and neurological examinations were negative. After a bout of delirium tremens he was alert and oriented by the fourth hospital day. A lumbar puncture at that time revealed grossly bloody spinal fluid with a xanthochromic supernatant. During the following days the patient remained alert and exhibited only a “glove and stocking” sensory impairment of the limbs. Ten weeks after admission a right carotid angiogram (Fig. 2) revealed a chronic subdural fluid collection. Six days later a right parietal burr hole was made and a 20-gauge needle was inserted through the dura.