This article was downloaded by: [University of Birmingham] On: 10 January 2015, At: 14:27 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/ncny20 Neuropsychological profile following suicide attempt by hanging: two adolescent case reports a a a Andrew T. Zabel , Beth Slomine , Kathy Brady & James Christensen a a Kennedy Krieger Institute and Johns Hopkins University School of Medicine Published online: 16 Feb 2007. To cite this article: Andrew T. Zabel , Beth Slomine , Kathy Brady & James Christensen (2005) Neuropsychological profile following suicide attempt by hanging: two adolescent case reports, Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence, 11:4, 373-388, DOI: 10.1080/09297040490916965 To link to this article: http://dx.doi.org/10.1080/09297040490916965 PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. 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ISSN: 0929-7049 print DOI: 10.1080/09297040490916965 NEUROPSYCHOLOGICAL PROFILE FOLLOWING SUICIDE ATTEMPT BY HANGING: TWO ADOLESCENT CASE REPORTS Downloaded by [University of Birmingham] at 14:27 10 January 2015 T. Andrew Zabel, Beth Slomine, Kathy Brady and James Christensen Kennedy Krieger Institute and Johns Hopkins University School of Medicine Hippocampal damage and amnesia following hypoxia and ischemia are described in the few published adult cases of suicide attempt by hanging. However, a recent review (Caine & Watson, 2000) suggests a variable pattern of brain involvement and neuropsychological impairments following hypoxic-ischemic injury that may or may not involve amnesia. To help clarify the impact of hanging on the developing brain, we examined neuropsychological functioning in two adolescents who survived suicide attempt by hanging. Despite differences in Glasgow Coma Scale (GCS), coma duration, and structural imaging findings, both patients had similar IQ (VIQ > PIQ) and presented with various combinations of deficits in expressive/receptive language, visual-constructional and perceptual ability, processing speed, attention, working memory, and/or executive functioning shortly after injury. In spite of their similarities, only one of the patients presented with classic amnesia symptoms in his early recovery. This patient was evaluated 1 year postinjury, and persistent deficits in processing speed and memory encoding were noted. Several hanging-related variables, including longer estimated hanging duration, greater weight, and severe airway edema, were thought to place this patient at increased risk for cognitive deficits. Clinical MRI scans of this patient obtained 6 weeks postinjury revealed mild volume loss as well as abnormalities in bilateral superior cortex. However, CT and MRI scans obtained throughout early recovery did not reveal overt evidence of injury to specific memory-related structures. Comprehensive neuropsychological evaluation of all adolescent survivors of suicide attempt by hanging is recommended, as a variety of postacute cognitive deficits were observed in these patients despite relatively short (≤ 15 minutes) estimated hanging durations. INTRODUCTION International surveillance efforts suggest that the male rate of suicide attempts by hanging increased dramatically during the 1980's and stabilized in the 1990’s (Langley, Nada-Raja, & Alsop, 2000). Of male suicide attempts occurring during adolescence in the United States, hanging is the most frequently employed of the highly lethal methods before age 15 (Li, Ling, DiScala, Nordenholz, Sterline, & Baker, 1997); in later adolescence, it matches the rate of suicide attempt by firearms (Weinberger, Sreenivasan, Sathyavagiswaran, & Markowitz, 2001). In a cohort of suicide victims and survivors 15 years of age or younger (National Pediatric Trauma Registry–Phase II), the majority of hangings Address correspondence to T. Andrew Zabel, Department of Neuropsychology, Kennedy Krieger Institute, 1750 East Fairmount Avenue, Baltimore, MD, 21231, Fax: 443-923-4470. E-mail: zabela@kennedykrieger.org. 373 Downloaded by [University of Birmingham] at 14:27 10 January 2015 374 T. A. ZABEL ET AL. were performed by boys (82%) and/or children under 14 years of age (79%; Li et al., 1997). The majority of children (68%) reported by Li and colleagues survived their suicide attempt by hanging, suggesting a high percentage of young adolescent survivors. Despite this high survival rate, few if any reports have been published regarding the neuropsychological sequelae of suicide attempt by hanging in adolescents. We present two adolescent case studies below, and use these cases to examine variables thought to be associated with the cognitive and behavioral impact of hanging on the developing brain. There are several studies of the neuropsychological sequelae of nonlethal hanging in adults, including isolated case studies (Berlyne & Strachen, 1968; Medalia, Merriam, & Ehrenreich, 1991) in which memory deficits are the primary finding. For instance, Medalia and colleagues (1991) reported on two adults who presented with retrograde/anterograde amnesia and otherwise intact cognitive functioning 2 to 3 years after hanging attempt. Isolated amnesia has also been associated with other hypoxic-ischemic conditions (Cummings, Tomiyasu, Read, & Benson, 1984; Volpe & Hirst, 1983; Zola-Morgan, Squire, & Amaral, 1986). However, in their review of 67 case studies/series involving hypoxic and anoxic injury of mixed etiologies, Caine and Watson (2000) found that memory disturbance rarely occurred without other accompanying cognitive dysfunction. Compared with incidence of isolated amnesia, they found a much higher rate of memory disturbance combined with other cognitive deficits, including changes in behavior, personality, visuospatial functioning, and expressive language skills. This pattern of multisystem involvement and deficit was also consistent with Caine and Watson’s review of associated neuropathologic findings in these patients with anoxia, as watershed cerebral cortex and basal ganglia injuries were more frequently reported than isolated damage to the hippocampus. As such, the Caine and Watson review suggests that multiple brain structures and cognitive functions may be disrupted following periods of hypoxia/anoxia, and argues against the commonly held belief that amnesia typically exists in isolation following such injuries. Hanging differs from many other causes of hypoxic-ischemic injury in that the ligature used in hanging can partially or completely occlude both air flow and arterial flow simultaneously. This is quite different from other forms of injury (e.g., asphyxia), in which decreased tissue oxygenation (i.e., hypoxia) can occur without immediate disruption of blood flow to brain tissue (i.e., ischemia). The link between hanging and the potential for immediate disruption of arterial blood flow is significant, as short periods of hypoxia alone have not been associated with cerebral necrosis in animal studies when minimal blood pressure has been preserved. In contrast, ischemia alone via carotid ligation has been linked to necrosis even when arterial blood oxygenation has been maintained (de Courten-Myers, Yamaguchi, Wagner, Ting, & Myers, 1985; Miyamoto & Auer, 2000). Pathologically, hypoxia and ischemia are distinct, as only ischemia has been found to lead to elevation of glutamate concentrations and secondary intracellular calcium toxicity (Choi, 1988; Pearigen, Gwinn, & Simon, 1996). Given the dynamics described above, several variables may be predictive of extent of brain injury and cognitive dysfunction following suicide attempt by hanging. These variables are interrelated but may expand our ability to predict differing levels of brain injury and functional impairment following a hanging attempt. One set of relevant injury variables includes the estimated time duration of hanging and the associated risk of cardiac arrest (Singhal, Topcuoglu, & Koroshetz, 2002). Although it follows that shorter hanging durations would result in less severe brain injury, research suggests that the relationship between duration of hypoxia and brain injury is not linear. A brief period of hypoxia can be tolerated without widespread necrosis due to protective hemodynamic mechanisms. Downloaded by [University of Birmingham] at 14:27 10 January 2015 NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 375 However, in cases of progressive hypoxia, when arterial oxygenation drops below 25 mm Hg for several minutes, these protective mechanisms are eventually overcome, resulting in cardiac decompensation and global hypoperfusion (Kogure, Scheinberg, Fujishima, Busto, & Reinmuth, 1970). With the onset of cardiac arrest and the loss of minimal blood flow perfusion, the protective action of the autoregulatory processes is lost. As such, hanging survivors are thought to be at increasing risk of cardiac arrest and ischemic injury the longer the duration of their hanging episode is sustained prior to rescue. Another set of injury variables specific to hanging that is thought to impact eventual neuropathology involves the mechanics of the hanging attempt itself. The introduction of ligature-induced ischemia places the patient at dramatically greater risk of brain injury compared to patients who are initially exposed to hypoxic conditions alone (e.g., suffocation). Several variables appear to mediate the degree of arterial occlusion in adolescent hanging. Weight of the adolescent likely has some influence upon arterial occlusion, as total body weight in older children and younger adolescents can often fall below the higher estimates of ligature pressure necessary to occlude both the vertebral and carotid arteries during hanging, i.e., 16 to 40 kilograms (Berlyne & Strachen, 1968; Khokhlov, 2001a). Positioning of the ligature during hanging and distribution of pressure is also thought to mediate the degree of occlusion exerted upon neck arteries. Forensic mathematical modeling of ligature-induced injuries and deaths suggest that ligature pressure along the neck can vary according to the degree of loop deflection and positioning (Khokhlov, 2001a). As such, the distribution of pressure along the ligature may or may not be sufficient to fully occlude arterial flow depending upon the adolescent’s weight and the position of the ligature. Finally, the degree of neck compression and pressure upon the arteries can also be partially relieved if the patient is in an “incomplete” hanging position, e.g., standing or kneeling (Khokhlov, 2001b). In the case studies below, we present the results of neuropsychological evaluation of two hanging survivors from a population demographic that is at increased risk for hanging attempts and related cognitive deficits. Caucasian males (Patients A and B) have the highest rate of completed suicide among adolescents, and boys are far more likely to utilize increasingly lethal methods such as hanging in their suicide attempts (Li et al., 1997). These cases are consistent with other findings concerning adolescents who attempt suicide. Parental separation (Patient A) is common in adolescent suicide, but many teens are living with both parents at the time of suicide attempt (Patient B; Shaffer & Hicks, 1993). Many adolescents who attempt suicide have a close family member who also attempted suicide in the past (Patient B; Roy, 1983). Substance abuse is not generally associated with early adolescent suicide attempt and was not an issue in either of the cases reported here. Teen suicide attempt often occurs following a stressful event, such as a disciplinary crisis (Patient A) or a recent disappointment or perceived rejection (Patients A and B; Shaffer, 1974). Finally, the majority of adolescent suicide attempts using highly lethal methods are thought to occur at home (Patients A and B; Li et al., 1997), increasing the chances of survival due to the potential opportunity for rescue. Multidisciplinary evaluation of both of these boys allowed for the potential detection of a wide range of cognitive and behavioral problems in the months following injury, and permitted us to explore the possibility of a diffuse pattern of cognitive impact. Additionally, follow-up evaluation of one of these patients allowed us to examine the course of recovery when amnestic symptoms are present in postacute recovery. 376 T. A. ZABEL ET AL. METHOD Participants Selected background and demographic data for Patients A and B are presented in Table 1. The purpose of this case study report was explained to the patients’ families by way of telephone contact or in person during a routine visit to Kennedy Krieger Institute’s Brain Injury Rehabilitation Clinic. Consent for inclusion in this case study publication was obtained from the parents of each of the children described. Downloaded by [University of Birmingham] at 14:27 10 January 2015 Materials and Procedure The current study describes the neuropsychological profiles of two adolescent boys who survived suicide attempt by hanging. Both boys were referred for neuropsychological monitoring and assessment as part of their program in acute inpatient rehabilitation and postacute day treatment. Informal measures were administered and behavioral observations were made during their initial recovery, and comprehensive neuropsychological evaluation was conducted several months postinjury shortly, before discharge from day treatment. Follow-up assessment of the patient with more severe functional impairment (Patient B) was conducted on an outpatient basis. Specific test measures used during initial and follow-up evaluations are identified in Table 2. Patient A was 11 years, 7 months old at time of hanging, and was initially tested by a neuropsychologist, a speech and language therapist, and an occupational therapist approximately 2 months post-injury. Patient B was 14 years, 3 months old at time of hanging, and was tested by a neuropsychologist, a postdoctoral neuropsychology resident, a speech and language therapist, and an occupational therapist approximately 4 months postinjury. Additionally, Patient B underwent follow-up evaluation by the same postdoctoral neuropsychology resident approximately 1 year post-injury. Measures used to assess both boys at the time of initial evaluation included the Wechsler Intelligence Scale for Children–Third Edition (WISC-III; Wechsler, 1991), Clinical Evaluation of Language Fundamentals–Third Edition (CELF-III; Semel, Wiig, Table 1 Comparison of Demographic and Injury-Related Variables. Age at time of injury Weight Pre-injury IQ estimate Drug/alcohol use Psychiatric history Precipitants to hanging Hanging ligature Estimated duration of hanging Initial respiratory status Initial cardiac status Initial GCS score Duration of coma Initial EEG Follow-up MRI Patient A Patient B 11 years, 7 months 30.7 kg average/high average none reported not significant discipline dog leash 5 minutes shallow weak 7 8 days abnormal normal 14 years, 3 months 58.8 kg high average none reported not significant teasing/rejection dog leash 10–15 minutes arrested weak 5 13 days abnormal abnormal bilaterally NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 377 Table 2 Tests Administered at initial and Follow-up Evaluation. Patient A Downloaded by [University of Birmingham] at 14:27 10 January 2015 Test CBCL WISC-III CELF-III JLO HVOT BFRT CVLT-C BNT WCST Gordon CPT Conner’s CPT-II Grooved pegboard RCFT Recall of objects (DAS) BASC BRIEF Patient B Initial Initial Follow-up X* X X X X X X X X X X* X X X X X X X X X X X X X X X X X X X X X X X *Ratings of pre-injury behavior provided by parents post-injuriously. CBCL = Child Behavior Checklist; WISC-III = Wechsler Intelligence Scale for Children - Third Edition; CELF-III = Clinical Evaluation of Language Fundamentals - Third Edition; JLO = Judgment of Line Orientation; HVOT = Hooper Visual Organization Test; BFRT = Benton Facial Recognition Test; CVLT-C = California Verbal Learning Test - Children's Edition; BNT = Boston Naming Test; WCST = Wisconsin Card Sorting Test; Gordon CPT = Vigilance subtest of the Gordon Diagnostic System; Conner’s CPT-II = Conner’s Continuous Performance Test – Second Edition; RCFT = Rey Complex Figure Test; DAS = Differential Abilities Scale; BASC = Behavior Assessment System for Children; BRIEF = Behavior Rating Inventory of Executive Functions. & Secord, 1995), Judgment of Line Orientation (JLO; Benton, Hamsher, Varney, & Spreen, 1983), Hooper Visual Organization Test (HVOT; Hooper, 1983); Benton Facial Recognition Test (BFRT; Benton, Sivan, Hamsher, Varney, & Spreen,1978), California Verbal Learning Test–Children's Edition (CVLT-C; Delis, Kramer, Kaplan, & Ober, 1994), Wisconsin Card Sorting Test (WCST; Heaton, Chelune, Talley, Kay, & Curtiss, 1993), and the Boston Naming Test (BNT; Kaplan, Goodglass, & Weintraub, 1983). Both boys took “continuous performance” tests at the time of initial assessment, but Patient A took the vigilance condition of the Gordon Diagnostic System (Gordon, 1991), whereas Patient B took the Conners’ Continuous Performance Test (Conners, 1995). These neuropsychological tests were repeated during Patient B’s 1-year follow-up neuropsychological evaluation. In addition to the measures mentioned above, tests administered only to Patient B at the time of initial and/or follow-up evaluation also include the Grooved Pegboard (Trites, 1989), the Rey Complex Figure Test (RCFT; Meyers & Meyers, 1995), the Recall of Objects subtest from the Differential Abilities Scales (DAS; Elliot, 1990), the Behavioral Assessment System for Children (BASC; Reynolds & Kamphaus, 1998), and the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000). Head CT and MRI scans were performed as part of each patient’s clinical care. For the purposes of this manuscript, both patients’ scans were reviewed by an independent neuroradiologist. 378 T. A. ZABEL ET AL. RESULTS Downloaded by [University of Birmingham] at 14:27 10 January 2015 Patient A—Background History of Injury. Patient A was 11 years, 7 months old at the time of his suicide attempt by hanging. He was the youngest of five children, and family factors were noteworthy for parental divorce. There is no reported family history of mental illness. There were no significant behavioral or emotional problems reported in postinjury parent ratings of Patient A’s preinjury behavior on the Child Behavior Checklist (CBCL; Achenbachk & Edelbrock, 1983). In retrospect, his parent noted that Patient A had voiced mild complaints of sadness and loneliness but was otherwise free of overt emotional distress or symptoms of depression prior to his suicide attempt. Standardized testing (TerraNova) conducted 1 month prior to suicide attempt indicated average to above average academic skills. Suicide attempt involved self-induced ligature injury using a pet leash anchored to the ceiling. Position of ligature was not documented, but Patient A was found in a “complete” hanging position. Patient A weighed approximately 30.7 kilograms at the time of injury. Known immediate precipitants included a large family gathering and a minor verbal behavioral reprimand. Parent estimate of duration of hanging was approximately 5 minutes. When found, Patient A’s lips were cyanotic, and he was unconscious. He developed profuse vomiting upon ligature release. His parent reported a positive carotid pulse at the scene and shallow respirations, and the parent initiated rescue breathing. Patient A was bagged en route to the hospital, and was intubated in the ER. He experienced multiple episodes of vomiting in the ER with likely aspiration. Initial GCS was 7/15, but improved to 11/15 after arrival to the emergency department and lightening of sedation. Course of Recovery. In terms of motor functioning, Patient A initially displayed decreased balance but was ambulating with assistance a week after injury. Gait was wide based, with stance phase slightly on the right and decreased arm swing on the left. He progressed quickly over the course of his inpatient stay and was independent in ambulation and all movements/transfers several weeks following injury. Cognitively, Patient A reliably followed single-step commands 8 days after injury. Immediate postinjury communication was primarily nonverbal, with limited singleword verbalization. Executive dysfunction was characterized by echopraxia, impulsivity, and emotional lability. A period of several hours of retrograde amnesia was reported that included loss of memory for the suicide attempt and precipitating events. However, as functioning improved and confusion declined, Patient A reported premorbid self-injurious ideation associated with feelings of sibling rejection and being “picked on.” Patient A was discharged from inpatient rehabilitation 26 days following injury and was admitted to a day-treatment rehabilitation center for 46 days. Neuroimaging/EEG. Initial CT scan on the day of injury was consistent with diffuse cerebral edema, blurring of the gray-white junction, and abnormality in the right caudate nucleus compatible with infarction. However, these findings were not visualized on follow-up CT scan (1 day postinjury) and MRI (2 weeks postinjury). Neck MRI performed shortly after injury was unremarkable. EEG performed 5 days following injury showed generalized slowing consistent with diffuse cerebral disturbance. NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 379 Downloaded by [University of Birmingham] at 14:27 10 January 2015 Patient A—Initial Evaluation Test scores from initial assessment are presented in Table 3. Approximately 2 months following nonlethal hanging, Patient A showed a significant discrepancy between average Verbal IQ and borderline Performance IQ. Additional neuropsychological deficits were noted in brief and sustained attention, working memory, graphomotor/mental processing speed, and expressive and receptive language skills. He was within normal limits on most measures of visual perception, but was impaired on a test of face matching. Executive dysfunction was noted during Patient A’s postacute rehabilitation. On a measure of problem solving and solution generation (Wisconsin Card Sorting Task), Patient A was able to generate new solution sets in response to rule changes on this measure. However, Patient A frequently made set-loss errors and struggled to sustain a consistent response pattern. Verbal learning and memory were inefficient, but Patient A displayed a limited ability to encode and retrieve novel verbal information. He displayed a “flat” learning slope on the five learning trials of a 15-item verbal list-learning test (CVLT–C). However, he was able to spontaneously recall a modest number of list items on the fifth learning trial (5 items), the short delay recall trial (3 items), and the long delay recall trial (7 items). Moreover, his performance was grossly within normal limits when a forced-choice delayed recognition format was used. Parent report and patient interview did not reveal evidence of suicidal ideation or intent during the acute period of rehabilitation, although Patient A was provided with adult monitoring as part of his risk management. During this time, Patient A presented with flat affect and restricted facial expression. As functioning improved and confusion declined, Patient A reported that he did not remember his suicide attempt but reported premorbid self-injurious ideation. During psychotherapy, he reported preinjury feelings of sadness regarding a relationship with an older sibling that had changed. He indicated that although they had once been very close, his older sibling had recently shown more interest in spending time with other children and less interest in Patient A. Based upon the findings noted above, referrals were made for ongoing therapy services following discharge from day-treatment programming. Moreover, cognitive interventions and accommodations were made in preparation for his school reentry. Three years post-injury, Patient A was reportedly enrolled in a special education inclusion program in his local school district. He received learning support in math and language arts, and attended regular education classes for the rest of his subjects. Parent report revealed a range of academic performance that included As, Bs, and Cs. Patient B—Background History of Injury. Patient B was 14 years, 3 months old at the time of his suicide attempt by hanging. He was the older of two children. Parents were married at the time of hanging attempt. Family history is significant for panic attacks and the completed suicide by hanging of a close relative approximately 10 years prior to Patient B’s attempt. There were no overt behavioral or emotional problems based on his parents’ post-injury ratings of his pre-injury behavior on the Child Behavior Checklist (CBCL). However, his parents noted peer teasing, an unreciprocated love interest, and failure to earn a position on a 380 T. A. ZABEL ET AL. Table 3 Summary of Selected Intellectual and Language Test Results. Downloaded by [University of Birmingham] at 14:27 10 January 2015 Patient A Patient B Test Initial Initial Follow-up WISC-III Verbal IQ♣ WISC-III Performance IQ♣ WISC-III Information WISC-III Similarities WISC-III Arithmetic WISC-III Vocabulary WISC-III Comprehension WISC-III Digit Span WISC-III Picture Completion WISC-III Coding WISC-III Picture Arrangement WISC-III Block Design WISC-III Object Assembly WISC-III Symbol Search CELF-III Concepts/Directions CELF-III Word Classes CELF-III Semantic Relationships CELF-III Listening to Paragraphs CELF-III Formulating Sentences CELF-III Recalling Sentences CELF-III Sentence Assembly CELF-III Word Associations CVLT-C List A Trial 1♦ CVLT-C List A Trial 5♦ CVLT-C SDFR♦ CVLT-C LDFR♦ CVLT-C Discriminability ♦ BNT JLO HVOT BFRT WCST No. of Categories Completed ♥ WCST Trials to 1st Category ♥ WCST Failure to Maintain Set ♥ WCST Learning to Learn ♥ Grooved Pegs – RH (Dominant) ♦ Grooved Pegs – LH (Non-Dominant) ♦ 97 75 9 10 5 9 11 2 9 4 1 6 10 – 4 5 3 5 4 5 6 3 −1 −3 −2.5 −1.5 −1 WNL WNL WNL Impaired >16 2-5 11-16 >16 – – 91 72 10 9 6 10 7 5 7 3 4 9 4 1 7 5 7 6 10 8 7 6 −1 −3.5 −4 −4.5 −4.5 WNL Impaired Impaired WNL 11-16 >16 >16 <1 −2.34 −1.57 97 84 12 10 7 11 7 8 7 2 7 10 12* 2 9 7 5 – – 10 10 – −1.5 −4.5 −4 −4 −3 WNL WNL WNL WNL >16 >16 >16 >16 −1.23 −0.5 *Reliable Change Index (RCI) ≥1.96. All scores are scaled scores except for ♣ (standard scores), ♦ (z-scores), and ♥ (%ile) WNL=Within Normal Limits; WISC-III=Wechsler Intelligence Scale for Children - Third Edition; CELF-III=Clinical Evaluation of Language Fundamentals - Third Edition; CVLT-C=California Verbal Learning Test - Children’s Edition; SDFR=Short Delay Free Recall; LDFR=Long Delay Free Recall; BNT=Boston Naming Test; JLO=Judgment of Line Orientation; HVOT=Hooper Visual Organization Test; BFRT= Benton Facial Recognition Test; WCST=Wisconsin Card Sorting Test. sports team as possible precipitants of suicide attempt. A journal and suicide message composed by Patient B suggested a history of suicidal ideation, with ongoing emotional distress regarding teasing and feelings of rejection. Premorbid academic functioning was strong, including assignment to honors classes in most academic areas. Standardized Downloaded by [University of Birmingham] at 14:27 10 January 2015 NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 381 testing (CRT) conducted in each of the 3 years prior to suicide attempt indicated above average academic functioning. Patient B’s suicide attempt involved self-induced ligature injury using a pet leash anchored to the ceiling. Ligature positioning was not assessed at the time, but hanging position was complete. Patient B weighed approximately 58.8 kilograms at the time of inpatient admission. There were no known immediate precipitants, and the suicide attempt was initiated after the completion of a morning chore. Estimated duration of hanging was approximately 10–15 minutes. At the time of rescue, parents reported a positive carotid pulse but pulmonary arrest. Rescue breathing was initiated and resulted in the return of spontaneous respiration. GCS was 5/15 at the scene and Patient B was not responsive to pain. He was intubated in the ER to support his airway, as C-Spine showed tremendous airway edema and supraglottic edema. He developed movements (e.g., facial distortion, extension/rigidity of limbs, eye deviation to the right) suggestive of seizures and was given Valproic Acid and Dilantin. No further overt seizure activity was noted. Course of Recovery. Although confused, Patient B was ambulating with assistance 2 weeks after injury. Poor balance and mild bilateral weakness improved progressively over the course of his inpatient stay, and independence was achieved in ambulation and movements/transfers within 2 months of injury. Cognitively, Patient B displayed spontaneous movements 2 days following injury, and followed simple commands 13 days following injury. Immediate post-injury communication was primarily nonverbal. As verbal communication returned, speech was characterized by dysfluency and word-cluttering. When Patient B spoke, speech production was excessively fast, and he was unaware of his slurring and periodic unintelligibility. Executive dysfunction was characterized by poor initiation and lack of motivation. As functioning improved and confusion declined, Patient B appeared surprised and confused when informed of the cause of his injury, and he reported that he did not remember feeling depressed or planning his hanging attempt. Patient B was discharged from inpatient care into a day-treatment program 35 days following injury, and was subsequently admitted to day-treatment rehabilitation services for 86 days. Neuroimaging/EEG. Initial neck CT showed tremendous airway edema and supraglottic edema. Initial head CT scan on the day of injury was consistent with diffuse cerebral edema without intracranial hemorrhage or midline shift. Diffusion-weighted MRI performed 2 weeks postinjury was consistent with bilateral paracentral gray and white matter abnormalities consistent with ischemic injury (Figure 1A–B). Examination of axial scans did not reveal evidence of infarction of the hippocampi. Follow-up diffusionweighted MRI (6 weeks post-injury) revealed mild parenchymal volume loss (Figure 1C) and mild hyperintense signal abnormality involving bilateral superior cortical gyri in a somewhat symmetric fashion. The hippocampi were well visualized and differentiated on coronal MRI scans at that time (Figure 1D). Post-injury EEG revealed generalized slowing. Patient B—Initial Evaluation Test scores from initial evaluation are presented in Table 3. Approximately 4 months post-injury, Patient B showed a significant discrepancy between average Verbal IQ (VIQ) and borderline Performance IQ (PIQ). Specific deficits were noted on measures of Downloaded by [University of Birmingham] at 14:27 10 January 2015 382 T. A. ZABEL ET AL. Figure 1 Diffusion-weighted MRI performed 2 weeks post-injury revealed bilateral cortical and white matter ischemic injury (A–B). Follow-up MRI (6 weeks postinjury) revealed sulcal widening and mild parenchymal volume loss (C), yet the hippocampi remain well visualized and differentiated (D). brief attention and working memory, graphomotor/mental processing speed, and sequencing. Variability was noted in brief verbal attentional span, as sentence memory was average and digit memory was in the borderline range. Patient B made considerable omission errors on a continuous performance measure. Expressive and receptive language skills were generally intact. Patient B showed intact skills in face matching but deficits on several other measures of perceptual functioning. Fine-motor speed and dexterity was impaired bilaterally. Executive dysfunction was noted during Patient B’s postacute rehabilitation. On a measure of problem solving and solution generation (Wisconsin Card Sorting Test), Patient B struggled to establish a solution set on this measure and was perseverative and had difficulty proposing new solution sets as the task progressed. His efficiency on this task did not improve over time, as he continued to use ineffective strategies despite performance feedback. Downloaded by [University of Birmingham] at 14:27 10 January 2015 NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 383 Although he displayed age-appropriate performance on one of the measures of verbal span and brief verbal attention (Sentence Memory), Patient B presented with severe impairment in verbal encoding and recall. He displayed a “flat” learning slope on the five learning trials of a 15-item verbal list-learning test (CVLT – C). Patient B could not recall any list items on either the short-or long-delay free recall trials despite having recalled 5 items following the fifth learning trial. Performance was also impaired when using the cued recall and recognition formats. Patient B was confabulatory on this recall task and presented with an unusually high number of intrusion errors. In addition to symptoms of anterograde amnesia, Patient B presented with retrograde amnesia for the events occurring several weeks before his suicide attempt. A PDA (personal digital assistant) device was introduced into Patient B’s rehabilitation to function as a memory prosthetic. He had considerable pre-injury skills in computer use and quickly mastered the procedures involved in recording information in the PDA to help accommodate for anterograde memory deficits. For instance, Patient B routinely recounted his activities at the end of the therapy day by scrolling through notes taken during sequential treatment sessions. The alarm function was also used in treatment and was programmed to cue Patient B to initiate various transitions in his treatment day. Parent report and patient interview did not reveal evidence of suicidal ideation or intent during the acute period of rehabilitation, although Patient B was provided with adult monitoring as part of his risk management. During this time, Patient B presented with flat affect and restricted facial expression. He did not report memories of suicidal ideation or intent. During his acute rehabilitation, the cause of injury was included in Patient B’s daily orientation review. He was not, however, asked to review his self-generated suicide documentation (i.e., suicide note). Daytime and nighttime one-to-one monitoring was utilized for the first several weeks of his acute recovery, and was progressively faded in conjunction with regular risk assessment. Family therapy was initiated with a private therapist in Patient B’s home community prior to discharge from inpatient care. Patient B—Follow-Up Evaluation Given the extent of memory disruption present in Patient B’s neuropsychological profile, follow-up assessment was conducted approximately 1 year postinjury. Test scores from the follow-up evaluation are presented in Table 3. At that time, he was enrolled in a private school in which he received modified curriculum, multiple intervention services, and specialized instruction in all subjects. For Patient B, academic progress was reported to occur at a very slow rate due to memory difficulties and problems with organization of work output. On WISC–III and CELF–III composite scales and subtest scales, Reliable Change Index (RCI) values were calculated using the method described in Jacobson and Truax (1991) to determine if observed changes between initial and follow-up evaluation subtest scores were clinically significant. Of note, many of the tests used provided standard error of measurement (SEM) data in yearly intervals. As Patient B was tested at two separate ages, at ages 14 and 15, two separate SEM values were typically available for subtests of the WISC–III and CELF–III. RCIs were calculated using the more conservative (i.e., larger) of the available SEMs. Changes in subtest or composite scores were considered to reflect clinically significant improvement or decline when RCI values exceeded 1.96. Upon follow-up evaluation, Patient B’s Verbal IQ was in the average range. PIQ fell within the low average range, and clinically significant improvement was noted on the Downloaded by [University of Birmingham] at 14:27 10 January 2015 384 T. A. ZABEL ET AL. Object Assembly subtest (RCI=1.96). Deficits in psychomotor and mental processing speed were persistent. Apparent improvement was noted in several areas of executive functioning. For instance, Patient B was able to efficiently complete a test of problem solving and solution generation, and was far less perseverative on this and other tasks. Although these results were encouraging, the prospect of practice effects on these measures could not be completely ruled out as the reason for performance improvement. Anecdotal parent and teacher reports suggested ongoing executive dysfunction in Patient B’s daily functioning. These concerns included problems with initiation and organization of schoolwork that were uncharacteristic of his preinjury functioning. In general, Patient B showed age-appropriate expressive and receptive language skills 1 year post-injury. Patient B showed improvement on measures of visual-perceptual functioning, with performance falling within normal limits on all measures. Fine-motor speed and dexterity had improved bilaterally but remained impaired on the right (dominant) side. Patient B’s performance on the CVLT–C 1 year after injury continued to reveal a flat learning curve and significant encoding deficits. Specifically, Patient B recalled 4 items of the first learning trial and could recall only 4 items following the fifth learning trial. Verbal recall remained greatly impaired, as he recalled only 2 items and 1 item after short and long delays, respectively. Cueing and recognition formats were of little benefit in terms of overall item recall. Additional assessment of visual memory (RCFT) and multisensory memory, i.e., visual and verbal stimuli (Recall of Objects subtest from the DAS), conducted exclusively during follow-up assessment was impaired but revealed evidence of limited encoding of information in these formats. “Real-world” memory deficits were reported by Patient B’s parents as they described his home and school functioning. However, they also reported that Patient B was continuing to effectively utilize a PDA device as a memory prosthetic and was using it to record his academic schedule, assignments, and noteworthy events in his post-injury functioning. One year post-injury, Patient B presented with an increased range of affect and facial expression, and behavioral presentation was calm and well regulated. Patient B did not display overt symptoms of behavioral or emotional impulsivity or disinhibition, and parent ratings fell within normal limits on checklists of behavioral/emotional control (BASC and BRIEF). Mild frustration was noted during the individual interview, as Patient B objected to the ongoing use of surveillance devices by his parents to monitor his whereabouts (e.g., an “electric eye” device in the hallway outside of his room at night). His parents reported ongoing concern regarding his lack of social initiation and withdrawal from peers. Family therapy sessions were continued through his postacute recovery to assist Patient B and his family in adjusting to changes in his cognitive presentation and to provide monitoring of affect and ongoing risk assessment. Despite persistent declarative memory difficulties, Patient B was oriented to the nature of his injury and aware of several areas of ongoing cognitive deficit. DISCUSSION The cases presented above are useful for examining the impact of time-limited periods of hanging on cognitive functioning during adolescence. This is an important area of inquiry, as hanging is the most commonly employed of the highly lethal suicide methods prior to age 15, and the potential for survival is relatively high in this population. Downloaded by [University of Birmingham] at 14:27 10 January 2015 NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 385 Although a modest body of research exists regarding the cognitive impact of hanging attempts on adults, little has been published regarding cognitive functioning and recovery in children and adolescents following this type of injury. We recognize that the case study format limits our ability to systematically examine the effects of specific injury-related variables that could potentially mediate brain injury. However, we believe that the cases presented above are useful for identifying a number of these injury-related variables for future research aimed at predicting postinjury cognitive outcome. Moreover, follow-up assessment of one of these patients who initially displayed amnestic symptoms allowed us to explore a trajectory of cognitive/emotional recovery that may be a useful “starting point” when coordinating the clinical care of similar patients. Postacute recovery patterns documented in these cases were consistent with the conclusions of Caine and Watson (2000) in their review of the cognitive impact of anoxic injury. In their review, Caine and Watson revealed that amnesia is not seen in all cases of hypoxic-ischemic injury, and it rarely exists as the only deficit in post-injury functioning. Only one of the patients we presented (Patient B) showed evidence of amnesia in his immediate recovery. The other patient (Patient A) initially displayed memory deficits that were less severe and these deficits improved as initial deficits in attention and executive dysfunction resolved. In addition to memory problems, early deficits were clearly identified in the areas of attention and language (Patient A) and visual-spatial functioning and executive functioning (both patients). We believe this highlights the importance of multidisciplinary or comprehensive assessment following hanging attempt by children and adolescents, as short-term outcome in these cases suggests impairments in cognitive domains other than, or in addition to, memory. Identification of such deficits and the formulation of associated interventions/accommodations are thought to be essential to an effective transition of these patients into educational and community settings following hospital discharge. Multiple areas of deficit were noted in the months following injury in both of these cases, but only one of the patients presented with classic symptoms of amnesia. Although the cases presented above share several common characteristics, they differ in a number of important areas. The impact of each of these variables could not be examined individually in a case study format. However, the constellation of variables provides convergent evidence of brain injury when examined as a whole and give clues regarding individual variables that may be more predictive of cognitive functioning following hanging injury. Although both boys experienced severe disruption of brain functioning, Patient B presented with more severe indicators of injury, including a longer estimated duration of hanging, the development of pulmonary arrest, a lower GCS score assigned at the scene of rescue, and a longer duration of coma. Patient B was older and subsequently weighed more than Patient A, a variable that may have contributed to increased occlusion of arterial blood flow in the neck during hanging and thus a greater risk for ischemia. Patient B presented with other variables suggestive of worse outcome, including airway and supraglottic edema that suggested increased pressure on the neck, greater occlusion of the arteries during hanging, and the potential for ongoing hypoxia/ischemia following rescue. Finally, brain MRI conducted several weeks following injury also showed more evidence of atrophy and pathological changes in Patient B compared with Patient A. In these cases studies, the patient with more severe indicators of injury (Patient B) presented with a greater level of postacute functional impairment. However, cognitive deficits were also evident in the other patient (Patient A) despite a very short estimated duration of hanging. There are several possible explanations for this finding. Both of the Downloaded by [University of Birmingham] at 14:27 10 January 2015 386 T. A. ZABEL ET AL. patients underwent multidisciplinary assessment prior to discharge from day-treatment rehabilitation, and deficits may have been more evident due to the broad scope and comprehensive nature of the testing conducted. Other explanations exist, however, including the possibility that the time duration of hanging for Patient A was underestimated. Additionally, the difference in age (approximately 3 years) between these two patients should not be discounted, as degree of neural plasticity as well as the developmental timing of the injury likely mediated cognitive outcome as well. In any case, we believe the deficits detected in Patient A highlight the importance of comprehensive neuropsychological assessment following suicide attempt by hanging in children and adolescents, even when the estimated duration of hanging is short and amnesic symptoms are not present. In these cases, acute executive functioning was consistent with two distinct patterns of behavioral change identified by Caine and Watson (2000) in their review of postanoxia functioning. That is, Patient A displayed behavioral disinhibition, poor set maintenance, and poorly modulated affect, whereas Patient B showed impairment in the initiation and organization of purposeful activity. These distinct postacute behavioral presentations could not be clearly linked to injury-related variables in the case study format. However, we find it interesting that post-injury patterns of executive dysfunction seemed to represent an exacerbation of pre-injury behavioral tendencies. This was hinted at in the differing circumstances of the boys’ actual hanging attempts, as the boy with the greater display of post-injury impulsivity (Patient A) also displayed a greater degree of behavioral impulsivity in his hanging attempt (i.e., attempting suicide immediately following a verbal reprimand). In contrast, the patient with less evidence of impulsivity following his injury (Patient B) also showed far less impulsivity and emotional reactivity in his suicide attempt (i.e., completing a routine chore prior to hanging). As noted, only one of the boys (Patient B) displayed a lasting pattern of anterograde amnesia following hanging attempt. Surprisingly, hippocampal damage was not visualized on clinical head MRI or CT during the 6 weeks following injury. Moreover, we were surprised at the lack of evidence of injury in many of the other structures thought to be highly vulnerable to hypoxic-ischemic conditions, including the putamen, caudate, and thalamus (White, Grossman, & Krause, 1993). One possible explanation for the lack of hippocampal findings was the predominant use of axial and saggital slices in Patient B’s neuroimaging studies, both orientations that do not fully visualize key portions of the hippocampus thought to be highly instrumental in declarative memory encoding, i.e., CA1 (Zola-Morgan, Squire, & Amaral, 1986). Neuroimaging techniques were limited to CT and structural MRI in both patient’s clinical care, and it remains possible that injury to these structures would have been visualized had other neuroimaging methods been used, e.g., positron emission tomography (PET) or diffusion tensor imaging (DTI). However, it is also possible that other areas of necrosis account for the amnesic presentation in Patient B. Research has shown that memory systems and structures can be disrupted, at least in part, by damage to surrounding perirhinal and parahippocampal cortex, which act as a relay between the hippocampus and other cortical inputs (Zola-Morgan, Squire, Amaral, & Suzuki, 1989). As such, evidence of general brain atrophy following presumed bilateral hypoxic-ischemic injury may be associated with increased risk of memory deficit, despite lack of overt evidence of injury to the hippocampus or other memory related structures on clinical scans. In conclusion, we believe these case studies provide compelling evidence for comprehensive neuropsychological evaluation of children and adolescents following suicide attempt by hanging. In both cases, postacute cognitive functioning was characterized by NEUROPSYCHOLOGICAL SEQUELAE OF HANGING 387 disruption of multiple cognitive systems, with cognitive deficits becoming increasingly evident as the scope of evaluation was widened. While postacute cognitive presentations were generally associated with the severity of injury-related variables, there was evidence of general cognitive dysfunction even when the estimated hanging duration was short and injury-related variables were less severe. Similarly, specific patterns of cognitive dysfunction (e.g., anterograde amnesia) existed in one patient in the absence of clear neuroradiologic findings typically associated with such dysfunction (.e.g., hippocampal damage). As such, comprehensive evaluation is necessary to detect cognitive deficits that may compound the risks posed to adolescent survivors in their post-injury functioning. Downloaded by [University of Birmingham] at 14:27 10 January 2015 ACKNOWLEDGMENTS We would like to thank Dr. Michael Kraut of the Johns Hopkins University School of Medicine for assistance in reviewing the patients’ CT and MRI scans. REFERENCES Achenbach, T. M., & Edelbrock, C. (1983). 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