Cranial Wounds Research Articles

Contribution of Computed Tomography in the Management of a Penetrating Knife Wound to the Skull: A Case Report and Review of the Literature

Introduction: Cranial wounds encephalic penetrating by stab are rare and repesent 0.4% of Head trauma. They are often observed in an attempt at autolysis in mentally ill people, or in physical aggression. We report here a case of an adolescent victim of attack by the penetration of a knife into his brain. Patient and method: This is a patient aged 17 years old, with no known medical history, admitted to the Emergency Reception Department of the Gabriel TOURE University Hospital for open head trauma following a physical attack with the penetration of a knife inside his headrane. The entire blade of the weapon was lodged in his brain parenchyma. The entry point was the right parietal bone. The patient had a Glasgow score of 15/15, with good hemodynamic status. The cranial scanner encephalic which was carried out a few minutes after his admission high lighted the presence of the knife blade at the level of parietal and temporal lobe of her hemisphere right. Result: The patient was operated successfully with extraction of a knife whose blade measured 6 to 7cm. A good postoperative evolution followed. Conscious and without motor deficit, he received a follow-up CT scan on day 7. Then he was released from the hospital with out patient follow-up. Conclusion: Cranial wounds-encephalic by penetration of a bladed weapon are very rare. The CT scan in emergency is the key examination to clarify the location, the number of foreign bodies, as well as brain lesions. They require rapid surgical treatment after CT evaluation. Their prognosis remains reserved regarding the severity of the head trauma, endocranial vascular lesions and infections.

Травматическая церебральная аневризма после проникающего пулевого ранения головного мозга

A clinical case of traumatic cerebral artery aneurysm formation after a penetrating diametrical gunshot wound is presented. Based on data of primary primary and delayed cerebral angiography, intraoperative imaging of the arterial appearance, the evolution (emergence and growth) of a traumatic cerebral aneurysm within 14 days after wounding is traced. The clinical observation is of interest due to a combination of factors: the presence of an unrelated wound aneurysm in the same basin, available intraoperative images of the injured artery as the initial stage of traumatic aneurysm formation, and the possibility to trace angiographic stages of aneurysm formation. Two-stage surgical treatment was performed: removal of the wounding projectile and intravascular intervention (implantation of a flow-deflecting stent) at the level of the aneurysm. In the conclusion the clinical picture, radiological signs of penetrating cranial wounds characteristic for traumatic aneurysm formation, and their treatment tactics are discussed.

Neurosurgery at Pearl Harbor: Ralph Cloward’s legacy

Ralph B. Cloward (1908-2000) was the sole neurosurgeon present during the Japanese attack on Pearl Harbor on December 7, 1941. Cloward operated on 42 patients in a span of 4 days during the attacks and was awarded a commendation signed by President Franklin D. Roosevelt in 1945 for his wartime efforts. During the attacks, he primarily treated depressed skull fractures and penetrating shrapnel wounds, but he also treated peripheral nerve and spine injuries in the aftermath. His techniques included innovative advancements such as tantalum cranioplasty plates, electromagnets for intracranial metallic fragment removal, and the application of sulfonamide antibiotic powder within cranial wounds, which had been introduced by military medics for gangrene prevention in 1939 and described for penetrating cranial wounds in 1940. Despite the severity of injuries encountered, only 2 soldiers died in the course of Cloward's interventions. As the sole neurosurgeon in the Pacific Theater until 1944, he remained in Honolulu through World War II's duration and gained immense operative experience through his wartime service. Here, the authors review the history of Cloward's remarkable efforts, techniques, injury patterns treated, and legacy.

The effects of a proprietary Manuka honey and essential oil hydrogel on the healing of acute full‐thickness wounds in dogs

To evaluate the effect of a proprietary Manuka honey essential oil hydrogel on the healing of acute, full-thickness wounds in dogs. Prospective, controlled, randomized, experimental study. Purpose-bred, adult, female beagles (n = 10). Two 2 × 2cm surgical wounds were created bilaterally on the trunk of each dog; each side was randomized to receive HoneyCure® (HOC) or standard-of-care (CON) dressings. Cranial wounds were for histopathological analysis and the caudal wounds for culture and planimetry. Total and open wound areas were measured with digital image planimetry at 15 time points. From these data, percent contraction and percent epithelialization were calculated. Tissue biopsies were obtained at 7 time points and histologic features scored. Cultures were obtained at 2 time points. Epithelialization was 11.7, 10.4, and 10.1 percentage points higher in HOC wounds compared to CON wounds at days 16, 18, and 21 respectively. Wound contraction and histological scores did not differ between groups. Cultures were positive in 7/40 (17.5%) wounds, with Staphylococcus pseudintermedius and Staphylococcus epidermidis isolated evenly. There was no difference of infection rate between the two groups; all infections were superficial and did not require treatment. This study did not provide evidence to support the application of HoneyCure® in small, acute wounds in healthy dogs. However, application may be beneficial in the early proliferative stage of wound healing and in wounds that would benefit from early, robust epithelialization.

Endemic violence in a pre-Hispanic Andean community: A bioarchaeological study of cranial trauma from the Majes Valley, Peru.

This study examines violence-related cranial trauma frequencies and wound characteristics in the pre-Hispanic cemetery of Uraca in the lower Majes Valley, Arequipa, Peru, dating to the pre- and early-Wari periods (200-750 CE). Cranial wounds are compared between status and sex-based subgroups to understand how violence shaped, and was shaped by, these aspects of identity, and to reconstruct the social contexts of violence carried out by and against Uracans. Presence, location, and characteristics (lethality, penetration, and post-traumatic sequelae) of antemortem and perimortem cranial fractures are documented for 145 crania and compared between subgroups. Cranial wounds are mapped in ArcGIS and the locational distribution of injuries is compared between male and female crania. Middle adult males were disproportionately interred at Uraca, particularly in the elite Sector I. The Uraca mortuary population presents the highest rate of cranial trauma reported for pre-Hispanic Peru: 67% of adults present trauma, and among those, 61.1% present more than one cranial injury. Males exhibit significantly more cranial trauma than females and present a higher mean number of injuries per person. Elite males show the highest mean number of injuries per person, more antemortem injuries, and are the only ones with perimortem cranial trauma, bladed injuries, penetrating injuries, and post-traumatic sequelae. Both sexes were most frequently injured on the anterior of the cranium, while the proportion of posterior injuries was higher for females. The rate, intensity, and locational patterns of cranial trauma suggests the community was engaged in raids and/or war with enemy groups, some of which may have increased physical violence between community members. Engaging in violence was likely a prerequisite for burial in the elite sector and was bound up with the generation and maintenance of social status differences linked to male social life.

336 Civilian Penetrating Craniocerebral Gunshot Injuries

Abstract INTRODUCTION Civillian cranial gunshot wounds (GSWs) remain a frequently lethal and highly morbid injury uncommon to many civilian trauma centers. The vast majority of these patients die prior to reaching medical care. Of those who do survive their initial injury, recent series have shown that over 50% will succumb to their injuries or in-the-hospital complications. Furthermore, experience from wartime theaters has taught us that these patients are vulnerable to a multitude of complications (i.e. CSF leak, wound breakdown, hydrocephalus, vascular injury). Thus, the need and potential for improvement in care and understanding of these patients is large. Here, we present our institution's series of cranial GSWs with an emphasis on detailing our complications. METHODS We retrospectively performed a chart review from 2015–2017. RESULTS >We identified 9 patients that underwent operative intervention in the form of decompressive craniectomy following a craniocerebral gunshot injury at a level 1 trauma center in Washington, D.C. The average age of patients was 31 years (3 females, 6 males) and time to operative intervention from initial presentation was less than 4 hours in 7 out of 9 patients and less than 12 hours in all patients. All patients underwent further operation for a multitude of reasons of which wound breakdown and CSF leak were the most common. These complications extended the hospital initial hospitalization for the majority of patients beyond 2 weeks and were invariably the cause of readmission of these patients. CONCLUSION Not only is aggressive and early intervention critical in caring for patients with cranial GSWs, but also it is important to be vigilant in looking for and preventing further secondary injury from subsequent complications such as wound infections/breakdown, CSF leaks, hydrocephalus and vasospasm. These almost inevitable complications must be anticipated in the treatment planning from the principal operation.

Versatility of the Latissimus Dorsi Free Flap during the Treatment of Complex Postcraniotomy Surgical Site Infections.

Background:Some intractable cases of postcraniotomy infection, which can involve compromised skin, an open frontal air sinus, and residual epidural dead space, have been reported. In such cases, reconstructing the scalp and skull is challenging.Methods:Between 2009 and 2016, the author treated 12 patients with recalcitrant postcraniotomy surgical site infections with latissimus dorsi (LD) free flaps. The patients’ ages ranged from 37 to 79 years (mean, 63.5 years), and their underlying diseases included subarachnoid hemorrhaging (n = 5), brain tumors (n = 4), and cerebral arteriovenous malformations (n = 3).Results:The LD free flap was used for scalp reconstruction in 3 cases, scalp reconstruction and separation of the intracranial and nasal cavities in 5 cases, and the obliteration of epidural dead space in 4 cases. Debridement followed by staged cranial reconstruction was carried out in 8 cases, and single-stage cranial reconstruction was conducted in 2 cases. The bone defects of the other 2 cases, which were small, were filled with LD musculo-adipose free flaps. The postoperative local appearance of the wounds was acceptable in every case, and no complications occurred.Conclusions:The LD free flap is a versatile tool for the treatment of complex postcraniotomy surgical site infections. This vascularized muscle flap is useful for controlling local infections because of its abundant vascularity. Moreover, its variety of uses means that it can resolve several problems in cases involving complex cranial wounds.

Low velocity penetrating frontal bone injury with a stone: an interesting case report

Penetrating Cranial wounds are rare. They most commonly occur through Orbital or temporal region. Penetrating wounds in frontal region are rare and mostly associated with high velocity. There are various etiological factors associated with such type of injuries. Computed tomography scan of head is useful in such injuries. In this case report, we are reporting an interesting case of low velocity penetrating frontal bone injury with a stone. Keywords: Foreign body, Scalp injury, Head injury

Reducing surgical site infections following craniotomy: examination of the use of topical vancomycin

Although the use of topical vancomycin has been shown to be safe and effective for reducing postoperative infection rates in patients after spine surgery, its use in cranial wounds has not been studied systematically. The authors hypothesized that topical vancomycin, applied in powder form directly to the subgaleal space during closure, would reduce cranial wound infection rates. A cohort of 150 consecutive patients who underwent craniotomy was studied retrospectively. Seventy-five patients received 1 g of vancomycin powder applied in the subgaleal space at the time of closure. This group was compared with 75 matched-control patients who were accrued over the same time interval and did not receive vancomycin. The primary outcome measure was the presence of surgical site infection within 3 months. Secondary outcome measures included tissue pH from a subgaleal drain and vancomycin levels from the subgaleal space and serum. Vancomycin was associated with significantly fewer surgical site infections (1 of 75) than was standard antibiotic prophylaxis alone (5 of 75; p < 0.05). Cultures were positive for typical skin flora species. As expected, local measured vancomycin concentrations peaked immediately after surgery (mean ± SD 499 ± 37 μg/ml) and gradually decreased over 12 hours. Vancomycin in the circulating serum remained undetectable. Subgaleal topical vancomycin was associated with a lower incidence of surgical site infections after craniotomy. The authors attribute this reduction in the infection rate to local vancomycin concentrations well above the minimum inhibitory concentration for antimicrobial efficacy. Topical vancomycin is safe and effective for reducing surgical site infections after craniotomy. These data support the need for a prospective randomized examination of topical vancomycin in the setting of cranial surgery.

Evaluating simulant materials for understanding cranial backspatter from a ballistic projectile.

In cranial wounds resulting from a gunshot, the study of backspatter patterns can provide information about the actual incidents by linking material to surrounding objects. This study investigates the physics of backspatter from a high-speed projectile impact and evaluates a range of simulant materials using impact tests. Next, we evaluate a mesh-free method called smoothed particle hydrodynamics (SPH) to model the splashing mechanism during backspatter. The study has shown that a projectile impact causes fragmentation at the impact site, while transferring momentum to fragmented particles. The particles travel along the path of least resistance, leading to partial material movement in the reverse direction of the projectile motion causing backspatter. Medium-density fiberboard is a better simulant for a human skull than polycarbonate, and lorica leather is a better simulant for a human skin than natural rubber. SPH is an effective numerical method for modeling the high-speed impact fracture and fragmentations.

Collagenase cream in non-stitched skin wounds after punch biopsy

BACKGROUND: The use of debriding drugs is not common in a situation of acute wound healing, despite its widespread use in chronic wound healing, with satisfactory results. Collagenase is one of the most used debriding drugs, and its application after a non-stitched skin wound biopsy could lead to a better wound healing outcome and less complication METHODS AND FINDINGS: Fifteen Wistar rats were used in this study; four excisional wounds were performed on the dorsum of each animal. Once in a day, collagenase cream was applied in the cranial wounds, while the caudal wounds were washed with isotonic saline. After 7, 14 and 21 postoperative days, 5 animals were randomly chosen for macroscopic and microscopic wound analysis. At the 7 th postoperative day: collagenase cream induced greater monocytes invasion, fibroblast invasion, collagen deposit, angiogenesis and reepithelialization. 14 th postoperative day: collagenase cream induced greater neutrophils invasion, fibroblasts invasion, collagen deposit, reepithelialization and higher proportion of type I collagen fibers. 21 st postoperative day: collagenase cream led to greater angiogenesis and reepithelialization. CONCLUSION: Collagenase cream led to a better wound healing outcome than simply saline rinse, induced earlier angiogenesis and inflammatory step; greater collagen deposit and reepithelialization.

Strategy in Front of Complex Infected Cranial Defects Overlying Dura Mater. Feasibility and Safety of Negative Pressure Wound Therapy

Although rare, large cranial infected defects are challenging for practitioners, especially when the dura mater is involved. These complex full-thickness wounds (scalp, bone, and dura mater) commonly occur after surgery, trauma or failed reconstructive procedures. Many patients are poor candidates for immediate reconstruction because of original pathology, patient's general state, previous radiotherapy, which compromises the locally available tissue, depth of the sepsis. For these challenging patients, a two-step procedure (cleanliness then reconstruction) has to be proposed. Recently, few authors report the use of negative pressure wound therapy, NPWT, in association with a first-step cleanliness surgery with encouraging results. Methods: We report three consecutive cases with standardized two-step procedure for complex full-thickness cranial wounds. First step is a cleanliness surgery associated with NPWT using a continue negative pressure ranging from 25 to 75 mm Hg. Safety of NPWT protocol is evaluated by neuropsychological and clinical examination. A second step for reconstruction is then performed. Results: Good outcomes were achieved in all cases without any complication due to NPWT with a 9-month follow-up. No significant difference was found between neuropsychological examination with or without NPWT. Conclusion: NPWT is a safe procedure optimizing local wound conditions for poor candidates for immediate reconstruction in complex infected cranial defects overlying the dura mater.

Diclofenac topical gel in excisional wounds maintain heal quality and reduce phlogistic signals.

To investigate diclofenac topical gel as an alternative to reduce phlogistic signals and maintain quality of wound repair. Fifteen Wistar rats were used in this study; four excisional wounds were performed on the dorsum of each animal. Once in a day, cranial wounds received topical diclofenac gel administration and caudal wounds were washed with isotonic saline. After seven, 14 and 21 postoperative days, five animals were randomly chosen for macroscopic and microscopic wound analysis. On the 7th day: diclofenac wounds showed significant higher scab formation, however showed less phlogistic signal; diclofenac wounds had larger area and had less neutrophil invasion. On the 14th day: No area difference was noted and diclofenac wounds showed less hyperemia and phlogistic signals; diclofenac wounds showed greater keratinocytes invasion. On the 21st day: Almost all wounds were closed and there were no difference regarding the type of scar formation; diclofenac wounds showed greater monocytes invasion and lower angiogenesis level. No difference was noted in any postoperative day regarding fibroblast invasion, collagen deposit quantity and quality. Diclofenac topical gel is capable of reducing phlogistic signals and do not cause fibroblast or keratinocyte downregulation thus do not lead to excisional wound healing impairment.

Predictors of outcome in civilian gunshot wounds to the head

Civilian gunshot wounds to the head (GSWH) are often deadly, but some patients with open cranial wounds need medical and surgical management and are potentially good candidates for acceptable functional recovery. The authors analyzed predictors of favorable clinical outcome (Glasgow Outcome Scale scores of 4 and 5) after GSWH over a 24-month period. The authors posited 2 questions: First, what percentage of civilians with GSWH died in the state of Maryland in a given period of time? Second, what were the predictors of favorable outcome after GSWH? The authors examined demographic, clinical, imaging, and acute care data for 786 civilians who sustained GSWH. Univariate and logistic regression analyses were used to analyze the data. Of the 786 patients in this series, 712 (91%) died and 74 (9%) completed acute care in 9 trauma centers. Of the 69 patients admitted to one Maryland center, 46 (67%) eventually died. In 48 patients who were resuscitated, the Injury Severity Score was 26.2, Glasgow Coma Scale (GCS) score was 7.8, and an abnormal pupillary response (APR) to light was present in 41% of patients. Computed tomography indicated midline shift in 17%, obliteration of basal cisterns in 41.3%, intracranial hematomas in 34.8%, and intraventricular hemorrhage in 49% of cases. When analyzed for trajectory, 57.5% of bullet slugs crossed midcoronal, midsagittal, or both planes. Two subsets of admissions were studied: 27 patients (65%) who had poor outcome (25 patients who died and 2 who had severe disability) and 15 patients (35%) who had a favorable outcome when followed for a mean period of 40.6 months. Six patients were lost to follow-up. Univariate analysis indicated that admission GCS score (p < 0.001), missile trajectory (p < 0.001), surgery (p < 0.001), APR to light (p = 0.002), patency of basal cisterns (p = 0.01), age (p = 0.01), and intraventricular bleed (p = 0.03) had a significant relationship to outcome. Multivariable logistic regression analysis indicated that GCS score and patency of the basal cistern were significant determinants of outcome. Exclusion of GCS score from the regression models indicated missile trajectory and APR to light were significant in determining outcome. Admission GCS score, trajectory of the missile track, APR to light, and patency of basal cisterns were significant determinants of outcome in civilian GSWH.

Autologous Immediate Cranioplasty with Vascularized Bone in High-Risk Composite Cranial Defects

Composite cranial defects in the setting of infection, irradiation, or cerebrospinal fluid leak present a significant risk for devastating neurologic sequelae. Such defects require soft-tissue coverage and skeletal reconstruction that can withstand the hostile environment of a precarious wound. Patients with high-risk composite cranial defects treated with free flap reconstruction containing a vascularized osseous component from 2003 to 2012 were reviewed retrospectively. Fourteen patients received autologous vascularized cranioplasties between 2003 and 2012 with a mean age of 55.7 years and a mean follow-up of 14.1 months. Preoperatively, all patients had infection, irradiation, cerebrospinal fluid leak, or a combination thereof. Thirteen patients (92.9 percent) were reoperative cases for recurrent tumor, infection, or both. Six patients (42.9 percent) failed previous reconstructive procedures. Tissue biopsy-proven infection was present in 10 patients (71.4 percent) with calvarial osteomyelitis, both osteomyelitis and meningitis, or scalp soft-tissue infection only. Nine patients (64.3 percent) suffered from malignancy and six of these patients were irradiated preoperatively. Cranioplasty was achieved as part of a chimeric free flap using rib, scapula, both rib and scapula, or ilium. Vascularized duraplasty using serratus anterior fascia as a component of the chimeric flap was performed in three patients. No flap losses occurred and all patients had resolution of infection. Soft-tissue and skeletal restoration are the two critical components of composite cranial reconstruction. The authors report outcomes of the largest series of one-stage immediate cranioplasty consisting of autologous soft tissue and vascularized bone in high-risk composite cranial wounds and suggest its application in defects associated with compromised wound beds. Therapeutic, IV.

Vacuum-assisted closure for complex cranial wounds involving the loss of dura mater

The aim in this study was to describe the safety and efficacy of vacuum-assisted closure (VAC) in patients with complex cranial wounds with extensive scalp, bone, and dural defects who were not candidates for immediate free tissue transfer. Five patients (4 men and 1 woman) ages 24-73 years with complex cranial wounds were treated with VAC at Wake Forest Baptist Medical Center. Etiologies included trauma, squamous cell carcinoma, and malignant meningioma. Cutaneous wound defects measured as large as 15 cm in diameter. Four of the 5 patients had open skull defects with concomitant dural defects, and 1 patient had dural dehiscence. After surgical debridement, all 5 patients were treated with the direct application of a VAC device to a reapproximated dura mater (1 patient), to a pericranial flap (1 patient), or to a regenerative tissue matrix overlying CNS tissue (3 patients). In all cases involving open cranial wounds, the VAC device promoted granulation tissue formation over the dural substitute, prevented CSF leakage, and kept the wounds free from local infection. The duration of VAC therapy ranged from 16 to 91 days. Although VAC therapy was intended as a temporary measure until these patients could be stabilized for larger tissue transfer procedures or they succumbed to their primary pathology, 1 patient had a successful skin graft following VAC therapy. Hydrocephalus requiring shunt placement developed in 2 patients during VAC therapy. The VAC dressings applied to a tissue matrix or other barrier over brain tissue in extensive cranial wounds are safe and well tolerated, providing a functional barrier and preventing infection.

Fatal Tetanus Complicating an Untreated Mild Open Head Injury: A Case-Illustrated Review of Cephalic Tetanus

Tetanus is now a rare disease in the Western world, but not so in developing countries. Cephalic tetanus, unlike some other local forms of the disease, is likely to be fatal. We describe the clinical presentation of a case of fatal cephalic tetanus complicating an unattended open non-severe head injury with a review of the literature on the disease. Few cases of cephalic tetanus complicating head injury are found in the world literature, and many were diagnosed late. Cephalic tetanus from open or compound depressed skull fracture is even more rare. Our patient was a young male with an uncertain tetanus immunization history who sustained mild head injury (scalp laceration) and an unattended open depressed skull fracture in a motorcycle crash. He developed cephalic tetanus seven days later, presented late to our service, and died while being prepared for surgical debridement of his cranial wounds. At the immediate post-trauma medical contact, in an across-the-street "clinic," he had received suboptimal care for his head wound and inadequate tetanus prophylaxis. Cephalic tetanus is a rare form of the disease. Although it is preventable easily by well-established medical and surgical treatment paradigms, it continues to catch many clinicians disastrously unaware.

Human Platelet-Rich Plasma- and Extracellular Matrix-Derived Peptides Promote Impaired Cutaneous Wound Healing In Vivo

Previous work in our laboratory has described several pro-angiogenic short peptides derived from endothelial extracellular matrices degraded by bacterial collagenase. Here we tested whether these peptides could stimulate wound healing in vivo. Our experiments demonstrated that a peptide created as combination of fragments of tenascin X and fibrillin 1 (comb1) applied into cranial dermal wounds created in mice treated with cyclophosphamide to impair wound healing, can improve the rate of wound closure. Furthermore, we identify and characterize a novel peptide (UN3) created and modified from two naturally-occurring peptides, which are present in human platelet-rich plasma. In vitro testing of UN3 demonstrates that it causes a 50% increase in endothelial proliferation, 250% increase in angiogenic response and a tripling of epithelial cell migration in response to injury. Results of in vivo experiments where comb1 and UN3 peptides were added together to cranial wounds in cyclophosphamide-treated mice leads to improvement of wound vascularization as shown by an increase of the number of blood vessels present in the wound beds. Application of the peptides markedly promotes cellular responses to injury and essentially restores wound healing dynamics to those of normal, acute wounds in the absence of cyclophosphamide impairment. Our current work is aimed at understanding the mechanisms underlying the stimulatory effects of these peptides as well as identification of the cellular receptors mediating these effects.

Pulmonary embolisation of bone fragments from penetrating cranial gunshot wounds

Bone embolism is a very rare event that usually occurs in trauma-induced septic bone lesions, after bone surgery or after bone marrow transplantation, and normally remains silent. To our knowledge, there are no previous reports of bone embolism after a gunshot to the head. We describe a case of pulmonary embolism associated with bone fragments after a gunshot to the head in which bone fragments surrounded by leukocytes, interstitial and intra-alveolar oedema and haemorrhage around the embolised vessels, leukostasis and fat and bone marrow embolism suggest that the survival time from the gunshot was sufficiently long to allow changes in lung microcirculation and lung tissue.

Transorbital penetrating cerebral injury with a ceramic stone: Report of an interesting case

Penetrating cranial injury is a potentially life-threatening condition. The majority of war injuries are high-velocity penetrating cranial injuries; but in civilian cases, most penetrating cranial wounds are low-velocity type. We report an interesting case of transorbital penetrating cranial injury with a knife-sharpening stone made up of ceramic in a 28-year-old male. The pertinent literature is reviewed and management of such cases is discussed.