Risk factors associated with subdural hygroma after decompressive craniectomy in patients with traumatic brain injury : a comparative study

Subdural Lesions Linking Additional Intracranial Spaces and Chronic Subdural Hematomas: A Narrative Review with Mutual Correlation and Possible Mechanisms behind High Recurrence

The purpose of this study was two-fold. The first was to investigate the pathologic mechanisms underlying the formation of subdural fluid collection, an umbrella term referring to a condition commonly seen in the clinical setting. Accumulation of the cerebrospinal fluid (CSF) in the subdural space can be referred to in this disease category, disregarding the underlying source of the subdural fluid. However, in these two clinical situations, especially after trauma or brain surgery, fluid collection from the subarachnoid space (subdural hygroma) or from the ventricle to the subarachnoid space and infusion into the subdural space (external hydrocephalus), surgical management of critical patients may adopt the strategies of burr-hole, subduroperitoneal shunt, or ventriculoperitoneal shunt, which present distinctly different thoughts. Crucially, the former can be further transformed into chronic subdural hematoma (CSDH). The second significant theme was the pathogenesis of CSDH. Once the potential dural border cell (DBC) layer is separated such as if a wound is formed, the physiological mechanisms that seem to promote wound healing will resume in the subdural space as follows: coagulation, inflammation, fibroblast proliferation, neovascularization, and fibrinolysis. These aptly correspond to several key characteristics of CSDH formation such as the presence of both coagulation and fibrinolysis signals within the clot, neomembrane formation, angiogenesis, and recurrent bleeding, which contribute to CSDH failing to coagulate and absorb easily. Such a complexity of genesis and the possibility of arising from multiple pathological patterns provide a reasonable explanation for the high recurrence rate, even after surgery. Among the various complex and clinically challenging subdural lesions, namely, CSDH (confined to the subdural space alone), subdural hygroma (linked in two spaces), and external hydrocephalus (linked in three spaces), the ability to fully understand the different pathological mechanisms of each, differentiate them clinically, and devote more interventional strategies (including anti-inflammatory, anti-angiogenic, and anti-fibrinolysis) will be important themes in the future.

Factors Associated With Subdural Hygroma Following Mild Traumatic Brain Injury

Objective

Subdural hygroma (SDG) is a complication of traumatic brain injury (TBI). In particular, the outcome and outpatient treatment period may vary depending on the occurrence of SDG. However, the pathogenesis of SDG has not been fully elucidated. Therefore, this study aimed to identify the risk factors associated with the occurrence of SDG after mild TBI.

Methods

We retrospectively analyzed 250 patients with mild TBI admitted to a single institution between January 2021 and December 2021. The SDG occurrence and control groups were analyzed according to the risk factors of SDG, such as age, history, initial computed tomography (CT) findings, and initial laboratory findings.

Results

The overall occurrence rate of SDG was 31.6% (n=79). A statistically significant association was found between preoperative diagnoses and the occurrence of SDG, such as subarachnoid hemorrhage (odds ratio [OR], 2.36; 95% confidence interval [CI], 1.26–4.39) and basal skull fracture (OR, 0.32; 95% CI, 0.12–0.83). Additionally, age ≥70 years (OR, 3.20; 95% CI, 1.74–5.87) and the use of tranexamic acid (OR, 2.12; 95% CI, 1.05–4.54) were statistically significant factors. The prognostic evaluation of patients using the Glasgow Outcome Scale (GOS) did not show any statistical differences between patients with and without SDG.

Conclusion

SDG was not associated with the prognosis of patients assessed using the GOS. However, depending on the occurrence of SDG, differences in patient symptoms may occur after mild TBI. Therefore, the early evaluation of patients with mild TBI and determination of the probability of developing SDG are important.

Nomogram for predicting traumatic subdural effusion after mild traumatic brain injury

Objective

Traumatic subdural effusion (TSE) is a common complication of traumatic brain injury (TBI). This study aimed to determine the risk factors associated with subdural effusion and to propose a nomogram to predict the risk of TSE in patients with mild TBI.

Methods

We retrospectively analyzed 120 patients with mild TBI between January 2015 and December 2020 at the Third People's Hospital of Hefei. The risk factors of TSE were selected using univariate and multivariable logistic regression analysis. A nomogram was developed to predict the incidence of TSE. Receiver operating characteristics and calibration plots were used to evaluate the discrimination and fitting performance.

Results

Of the 120 patients, 32 developed subdural effusion after mild TBI. Univariate analysis showed that gender, age, history of hypertension, traumatic subarachnoid hemorrhage, subdural hematoma, basilar skull fracture, and cerebral contusion were varied significantly between groups (p < 0.05). Logistic multivariate regression analysis showed that the gender, age, history of hypertension, and basilar skull fracture were independent risk factors for TSE. Based on these results, a nomogram model was developed. The C-index of the nomogram was 0.78 (95% CI: 0.70–0.87). The nomogram had an area under the receiver operating characteristic curve of 0.78 (95% CI: 0.70–0.87). The calibration plot demonstrated the goodness of fit between the nomogram predictions and actual observations.

Conclusion

Gender, age, history of hypertension, and basilar skull fracture can be used in a nomogram to predict subdural effusion after mild TBI.

Scenario for the use of effusion-peritoneal shunt necessary against subdural effusion secondary to decompressive craniectomy

OBJECTIVES

This study aimed to summarize the surgical strategies for subdural effusion secondary to decompressive craniectomy (SESDC) and discuss the applicable scenarios of effusion-peritoneal shunt (EP shunt).

METHODS

A total of 53 consecutive patients with SESDC were screened out of 7569 cases. The SESDC was divided into five types, and the treatment methods of each type were analyzed and compared. According to the implementation strategy of cranioplasty (CP), patients were divided into CP-first and delayed-CP groups. The differences in surgical methods were compared between the two groups.

RESULTS

All patients with SESDC in this cohort had undergone cranioplasty. Subcutaneous puncture and aspiration (SPAA) proved ineffective. Only 2/30 patients in the CP-first group used EP shunt, while 6/19 patients in the delayed-CP group used EP shunt; the difference was statistically significant (P = 0.03). A significant difference was found in the use of EP shunt among type 1, type 2, and type 5 SESDC (χ² = 6.778, P = 0.034).

CONCLUSIONS

CP combined with other treatments could cure most SESDC. EP shunt should be used preferentially in some specific scenarios in which CP cannot be performed first, rather than as a backup measure that can only be used when other preceding treatments fail.

Extra-Axial Fluid Collections After Decompressive Craniectomy: Management, Outcomes, and Treatment Algorithm

BACKGROUND

Extra-axial fluid collections (EACs) frequently develop after decompressive craniectomy. Management of EACs remains poorly understood, and information on how to predict their clinical course is inadequate. We aimed to better characterize EACs, understand predictors of their resolution, and delineate the best treatment paradigm for patients.

METHODS

We reviewed patients who developed EACs after undergoing decompressive craniectomy for treatment of refractory intracranial pressure elevations. We excluded patients who had an ischemic stroke, as EACs in these patients have a different clinical course. We performed univariate analysis and multiple linear regression to find variables associated with earlier resolution of EACs and stratified our analyses by EAC phenotype (complicated vs. uncomplicated). We conducted a systematic review to compare our findings with the literature.

RESULTS

Of 96 included patients, 73% were male, and median age was 42.5 years. EACs resolved after a median of 60 days. Complicated EACs were common (62.5%) and required multiple drainage methods before cranioplasty. These were not associated with a protracted course or increased risk of death (P > 0.05). Early bone flap restoration with simultaneous drainage was independently associated with earlier resolution of EACs (β = 0.56, P < 0.001). Systematic review confirmed lack of standardized direction with respect to EAC management.

CONCLUSIONS

Our analyses reveal 2 clinically relevant phenotypes of EAC: complicated and uncomplicated. Our proposed treatment algorithm involves replacing the bone flap as soon as it is safe to do so and draining refractory EACs aggressively. Further studies to assess long-term clinical outcomes of EACs are warranted.

Factors involved in the development of subdural hygroma after decompressive craniectomy for traumatic brain injury. A systematic review and meta-analysis

Subdural hygroma (SDG) represents a common complication following decompressive craniectomy (DC). To our knowledge we present the first meta-analysis investigating the role of clinical and technical factors in the development of SDG after DC for traumatic brain injury. We further investigated the impact of SDG on the final prognosis of patients. The systematic review of the literature was done according to the PRISMA guidelines. Two different online medical databases (PubMed/Medline and Scopus) were screened. Four articles were included in this meta-analysis. Data regarding age, sex, trauma dynamic, Glasgow Coma Scale (GCS), pupil reactivity and CT scan findings on admission were collected for meta-analysis in order to evaluate the possible role in the SDG formation. Moreover we studied the possible impact of SDG on the outcome by evaluating the rate of patients dead at final follow-up and the Glasgow Outcome Scale (GOS) at final follow-up. Among the factors available for meta-analysis only the basal cistern involvement on CT scan was associated with the development of a SDG after DC (p < 0.001). Moreover, patients without SDG had a statistically significant better outcome compared with patients who developed SDG after DC in terms of GOS (p < 0.001). The rate of patients dead at follow-up was lower in the group of patients without SDH (8.25%) compared with patients who developed SDG (11.51%). SDG after DC is a serious complication affecting the prognosis of patients. Further studies are needed to define the role of some adjustable technical aspect of DC in preventing such a complication.

Risk factors associated with the progression of extra-axial hematoma in the original frontotemporoparietal site after contralateral decompressive surgery in traumatic brain injury patients

PURPOSE

To introduced our experience with progressive extra-axial hematoma (EAH) in the original frontotemporoparietal (FTP) site after contralateral decompressive surgery (CDS) in traumatic brain injury patients and discuss the risk factors associated with this dangerous situation.

METHODS

This retrospective study was conducted on 941 patients with moderate or severe TBI treated in Daping Hospital, Army Medical University, Chongqing, China in a period over 5 years (2013-2017). Only patients with bilateral lesion, the contralateral side being the dominant lesion, and decompressive surgery on the contralateral side conducted firstly were included. Patients were exclude if (1) they underwent bilateral decompression or neurosurgery at the original location firstly; (2) although surgery was performed first on the contralateral side, surgery was done again at the contralateral side due to re-bleeding or complications; (3) patients younger than 18 years or older than 80 years; and (4) patients with other significant organ injury or severe disorder or those with abnormal coagulation profiles. Clinical and radiographic variables reviewed were demographic data, trauma mechanisms, neurological condition assessed by Glasgow coma scale (GCS) score at admission, pupil size and reactivity, use of mannitol, time interval from trauma to surgery, Rotterdam CT classification, type and volume of EAH, presence of a skull fracture overlying the EAH, status of basal cistern, size of midline shift, associated brain lesions and types, etc. Patients were followed-up for at least 6 months and the outcome was graded by Glasgow outcome scale (GOS) score as favorable (scores of 4-5) and unfavorable (scores of 1-3). Student's t-test was adopted for quantitative variables while Pearson Chi-squared test or Fisher's exact test for categorical variables. Multivariate logistic regression analysis was also applied to estimate the significance of risk factors.

RESULTS

Initially 186 patients (19.8%) with original impact locations at the FTP site and underwent surgery were selected. Among them, 66 met the inclusion and exclusion criteria. But only 50 patients were included because the data of the other 16 patients were incomplete. Progressive EAH developed at the original FTP site in 11 patients after the treatment of, with an incidence of 22%. Therefore the other 39 patients were classified as the control group. Multivariate logistic regression analysis showed that both the volume of the original hematoma and the absence of an apparent midline shift were significant predictors of hematoma progression after decompressive surgery. Patients with fracture at the original impact site had a higher incidence of progressive EAH after CDS, however this factor was not an important predictor in the multivariate model. We also found that patients with progressive EAH had a similar favorable outcome with control group.

CONCLUSION

Progressive EAH is correlated with several variables, such as hematoma volumes ≥10 mL at the original impact location and the absence of an apparent midline shift (<5 mm). Although progressive EAH is devastating, timely diagnosis with computed tomography scans and immediate evacuation of the progressive hematoma can yield a favorable result.

Factors associated with the development and outcome of hydrocephalus after decompressive craniectomy for traumatic brain injury

Posttraumatic hydrocephalus (PTH) is common in patients undergoing decompressive craniectomy (DC) for traumatic brain injury (TBI), but the incidence, mechanisms, and risk factors have not been fully elucidated. This study aimed to determine the incidence of and the factors associated with PTH. We retrospectively reviewed patients who underwent DC for TBI at our institute between January 2014 and December 2018. We identified and compared the demographic, clinical, and radiological data, and 12-month functional outcome (as assessed by the Glasgow Outcome Scale [GOS]) between patients who developed PTH and those who did not. Logistic regression analyses were performed to identify risk factors for PTH. Additionally, the influence of PTH on unfavorable functional outcome was analyzed. PTH developed in 18 (18.95%) of the 95 patients who survived at 1 month after DC. A multivariate analysis indicated that postoperative intraventricular hemorrhage (odds ratio [OR] 4.493, P = 0.020), postoperative subdural hygroma (OR 4.074, P = 0.021), and postoperative hypothermia treatment (OR 9.705, P = 0.010) were significantly associated with PTH. The 12-month functional outcome significantly differed between the patients who developed PTH and those who did not (P = 0.049). Patients who developed PTH had significantly poorer 12-month functional outcomes than those who did not (P = 0.049). Another multivariate analysis indicated that subdural hemorrhage (OR 6.814, P = 0.031) and the presence of at least one dilated pupil before DC (OR 8.202, P = 0.000) were significantly associated with unfavorable functional outcomes (GOS grades 1-3). Although the influence of PTH (OR 5.122, P = 0.056) was not statistically significant in the multivariate analysis, it had a great impact on unfavorable functional outcomes. PTH considerably affects functional outcomes at 12 months after DC for TBI. Furthermore, postoperative imaging findings such as intraventricular hemorrhage and subdural hygroma can predict the development of PTH; therefore, careful observation is required during the follow-up period.

The Risk Factors of Subdural Hygroma after Decompressive Craniectomy

Objective

Subdural effusion, also known as subdural hygroma (SDG), is a secondary complication that can occur after decompressive craniectomy (DC). However, the pathogenesis of SDG is not fully understood. It is unclear whether SDG occurrence is related to preoperative patient status or surgical technique. The purpose of this study is to identify risk factors for SDG after DC.

Methods

Fifty-nine patients who underwent DC from January 2016 to December 2016 at the same institution were analyzed. We retrospectively reviewed the clinical and radiological features of the patients. We divided the patients into two groups based on the occurrence of SDG after DC. The risk factors for SDG were analyzed.

Results

The overall SDG rate after DC was 39% (23 patients). A statistically significant association was observed between preoperative diagnosis, e.g., subdural hemorrhage (SDH; odds ratio [OR], 4.99; 95% confidence interval [CI], 1.36–18.34) or subarachnoid hemorrhage (SAH; OR, 4.18; 95% CI, 1.07–16.32), and the occurrence of SDG after DC. Traumatic brain injury (OR, 4.91; 95% CI, 1.35–17.91) and preoperative cortical opening (OR, 4.77; 95% CI, 1.39–16.32) were important risk factors for SDG. Several surgical techniques did not show a statistically significant association with SDG. The occurrence of SDG after DC was related to the length of hospital stay (p=0.012), but not to prognosis.

Conclusion

After DC, SDG is not related to patients' prognosis but to the length of hospital stay. Therefore, it is necessary to study the occurrence of postoperative SDG by confirming the presence of preoperative SDH, SAH, and cortical opening.

Factors Associated Postoperative Hydrocephalus in Patients with Traumatic Acute Subdural Hemorrhage

Objective

Postoperative hydrocephalus is a common complication following craniectomy in patients with traumatic brain injury, and affects patients' long-term outcomes. This study aimed to verify the risk factors associated with the development of hydrocephalus after craniectomy in patients with acute traumatic subdural hemorrhage (tSDH).

Methods

Patients with acute traumatic SDH who had received a craniectomy between December 2005 and January 2016 were retrospectively assessed by reviewing the coexistence of other types of hemorrahges, measurable variables on computed tomography (CT) scans, and the development of hydrocephalus during the follow-up period.

Results

Data from a total of 63 patients who underwent unilateral craniectomy were analyzed. Postoperative hydrocephalus was identified in 34 patients (54%) via brain CT scans. Preoperative intraventricular hemorrhage (IVH) was associated with the development of hydrocephalus. Furthermore, the thickness of SDH (p=0.006) and the extent of midline shift before craniectomy (p=0.001) were significantly larger in patients with postoperative hydrocephalus. Indeed, multivariate analyses showed that the thickness of SDH (p=0.019), the extent of midline shift (p<0.001) and the coexistence of IVH (p=0.012) were significant risk factors for the development of postoperative hydrocephalus. However, the distance from the midline to the craniectomy margin was not an associated risk factor for postoperative hydrocephalus.

Conclusion

In patients with acute traumatic SDH with coexisting IVH, a large amount of SDH, and a larger midline shift, close follow-up is necessary for the early prediction of postoperative hydrocephalus. Furthermore, craniectomy margin need not be limited in acute traumatic SDH patients for the reason of postoperative hydrocephalus.

Outcome Determinants of Decompressive Craniectomy in Patients with Traumatic Brain Injury; A Single Center Experience from Southern Iran

OBJECTIVE

To investigate the determinants of outcome in patients with traumatic brain injury (TBI) undergoing decompressive craniectomy (DC) in a large level I trauma center in southern Iran.

METHODS

This retrospective cross-sectional study was conducted during an 18-month period from 2013 to 2014 in Shahid Rajaei hospital, a Level I trauma center in Southern Iran. Patients with TBI who had undergone DC were included and the medical charts were reviewed regarding demographics, clinical, radiological and outcome characteristics. The outcome was determined by extended Glasgow outcome scale (GOS-E) after one year of surgery. The variables were compared between those with favorable and unfavorable outcome to investigate the outcome determinants.

RESULTS

Overall 142 patients with mean age of 34.8 ± 15.5 (ranging from 15 to 85) years were included. There were 127 (89.4%) men and 15 (10.6%) women among the patients. After 1-year, the mortality rate was 58 (40.8%) and 8 (5.6%) patients were persistent vegetative state. The final outcome was found to be unfavorable in 77 (54.2%) patients.  Unfavorable outcome was associated with lower GCS on admission (p<0.001) as well as occurrence of postoperative hydrocephalus (p=0.011). Formation of the postoperative subdural hygroma after the operation was found to be associated with favorable outcome (p=0.019).

CONCLUSION

DC in patients with TBI is associated with favorable outcome in most of them. On admission GCS, postoperative hydrocephalus and presence of postoperative subdural hygroma are among the important predictors of outcome in TBI patients undergoing DC.

The Risk Factors for Hydrocephalus and Subdural Hygroma after Decompressive Craniectomy in Head Injured Patients

Objective

The present study aims to investigate 1) the risk factors for hydrocephalus and subdural hygroma (SDG) occurring after decompressive craniectomy (DC), and 2) the association between the type of SDG and hydrocephalus.

Methods

We retrospectively reviewed the clinical and radiological features of 92 patients who underwent DC procedures after severe head injuries. The risk factors for developing post-traumatic hydrocephalus (PTH) and SDG were analyzed. Types of SDGs were classified according to location and their relationship with hydrocephalus was investigated.

Results

Ultimately, 26.09% (24/92) of these patients developed PTH. In the univariate analyses, hydrocephalus was statically associated with large bone flap diameter, large craniectomy area, bilateral craniectomy, intraventricular hemorrhage, contralateral or interhemisheric SDGs, and delayed cranioplasty. However, in the multivariate analysis, only large craniectomy area (adjusted OR=4.66; p=0.0239) and contralateral SDG (adjusted OR=6.62; p=0.0105) were significant independent risk factors for developing hydrocephalus after DC. The incidence of overall SDGs after DC was 55.43% (51/92). Subgroup analysis results were separated by SDG types. Statistically significant associations between hydrocephalus were found in multivariate analysis in the contralateral (adjusted OR=5.58; p=0.0074) and interhemispheric (adjusted OR=17.63; p=0.0113) types.

Conclusion

For patients who are subjected to DC following severe head trauma, hydrocephalus is associated with a large craniectomy area and contralateral SDG. For SDGs after DC that occur on the interhemispherical or controlateral side of the craniectomy, careful follow-up monitoring for the potential progression into hydrocephalus is needed.

Acute enlargement of subdural hygroma due to subdural hemorrhage in a victim of child abuse

An 11-month-old female baby was found dead by her mother. Cranial postmortem CT prior to the forensic autopsy showed dilatation of bilateral extra-axial spaces and ventricles. The autopsy revealed a new linear fracture of the left parietal bone and occipital bone, and a healed linear fracture of the right parietal bone and occipital bone like a mirror image of the left one as well. Intracranially, 230ml of subdural fluid were collected, which was mixed with blood. There was a fresh hemorrhage around a bridging vein of the left parietal lobe and the dura mater. Moreover, the outer side of the cerebrum and the inner side of the dura mater were covered by a thin membrane, which mater might have been previously formed because of being positive for Fe-staining and anti-CD68 antibody. A subdural hematoma might have been developed when the right side of the skull was previously fractured, which was transformed into a subdural hygroma. Subsequently, it is likely that, after the left side fracture of the skull occurred, the subdural hygroma rapidly enlarged due to hemorrhaging from the bridging vein, which resulted in intracranial hypertension, because microbleeding was detected in the brain stem. Accordingly, we diagnosed the cause and manner of death as intracranial hypertension due to subdural hemorrhage in subdural hygroma, and homicide, including child abuse, respectively.

Contralateral extraaxial hematomas after urgent neurosurgery of a mass lesion in patients with traumatic brain injury

PURPOSE

The development of a contralateral extraaxial hematoma has repeatedly been described in small series and descriptive studies. However, the evidence available to date is limited.

OBJECTIVES

To evaluate the incidence and risk factors leading to the development of a contralateral extraaxial hematoma and to describe the characteristics of cases.

METHODS

A retrospective cohort study with prospective data collection was undertaken. All patients admitted to an intensive care unit (ICU) from 2006 to 2010 were studied. The inclusion criteria were as follows: severe trauma [Injury Severity Score (ISS ≥ 16)], neurosurgery (NeuroSx) in the first 24 h. The following were excluded: subacute/chronic subdural hematomas, first bilateral NeuroSx. Cases were those who required immediate contralateral NeuroSx after the first NeuroSx due to the occurrence of a new extraaxial injury or significant growth of a previous one. Controls were those patients those who did not require second NeuroSx or who required reoperation due to ipsilateral lesions. The variables considered were: demographics, neurological assessment, traumatic injuries and severity, image and surgical findings, clinical course, and outcome. Statistics analysis comprised descriptive, inferential, and multivariate analysis by logistic regression.

RESULTS

A total of 120 patients were included, among which there were 11 cases (incidence 9.2 %). The cases showed a significantly higher frequency of coma or severe traumatic brain injury (TBI) at admission, contralateral injury and contralateral skull fracture in the preoperative computed tomography (CT) scan, as well as decompressive craniectomy. There were no significant differences in the severity scores, clinical course, or outcomes. The presence of contralateral fracture was identified as an independent risk factor [relative risk (RR) 47.9, 95 % confidence interval (CI) 5.2-443].

CONCLUSIONS

Contralateral extraaxial hematoma is a rare entity, although it has a high mortality rate. Therefore, it requires a high index of suspicion, especially in patients with severe TBI, with minimal contralateral injury and mainly with contralateral skull fracture on the initial CT scan.