Long-term outcomes following pediatric endoscopic titanium ossiculoplasty: A single-institution experience

INTRODUCTION

Endoscopic ossicular chain reconstruction (OCR) in adults has demonstrated equivalent outcomes to the traditional microscopic approach. Less data exist on endoscopic OCR outcomes in children, who have unique considerations including a smaller transcanal corridor and variable pathology. The purpose of this study was to investigate surgical and audiometric outcomes in children undergoing fully endoscopic and endoscopic-assisted OCR in both the short and long-term.

METHODS

Retrospective review of all children (<17 years) who underwent endoscopic OCR at one tertiary care center between 2017 and 2021. Children undergoing primary and revision endoscopic OCR with either partial (PORP) and total ossicular reconstruction prostheses (TORP) were included. Children undergoing surgery for juvenile otosclerosis or congenital stapes fixation, or any child receiving a stapes prosthesis were excluded. Primary outcome measures were post-operative change in 4 frequency (500 Hz, 1, 2, 4 KHz) air conduction pure tone average (AC PTA) and change in air-bone gap (ABG). Secondary measures included need for readmission and/or revision surgery, complication rate, and surgery duration.

RESULTS

Seventeen patients met inclusion criteria. Average age was 11.3 years (range, 5-17 years); 14 were male. A variety of fixed length, titanium total and partial prostheses were used. The most common prosthesis length was 2 mm (range 2-5 mm), and there were no intra- or perioperative complications. Mean long-term follow-up was 2.6 years. Most common pathology was congenital cholesteatoma (11/17, 64%), followed by chronic otitis media with tympanic membrane perforation (5/17, 29.4%), and extruded prosthesis (1/17, 5.9%). Intraoperatively, the most common finding was incus erosion (10/17, 58.8%), followed by malleus erosion (6/17, 35.3%), stapes erosion (4/17, 23.5%), and stapes absence (4/17, 23.5%). Eight children (47%) were reconstructed with PORPs, and 9 children (52.9%) were reconstructed with TORPs. Average ABG improved from 36.8 dB preoperatively to 19.9 dB postoperatively in the short-term and remained stable at 19.5 dB in the long-term. Average short-term ABG improvement was 4.2 dB for PORPs and 18 dB for TORPs. In the long-term, average ABG improved by 2.3 dB in PORPs and 13.4 dB in TORPs. PORPs had higher rates of ABG closure and lower AC PTAs than TORPs in the long-term.

DISCUSSION

Endoscopic ossiculoplasty is a viable option in children presenting with ossicular erosion from various causes. Audiometric improvement following endoscopic partial and total ossicular reconstruction remains stable over time, with a preference towards partial in the long-term, and mirrors published outcomes for microscopic surgery.

The Role of Lumbar Drains in the Perioperative Management of Primary Spontaneous Temporal Lobe Encephaloceles and Cerebrospinal Fluid Leaks

OBJECTIVE

To examine the role of lumbar drains (LDs) in the success of spontaneous temporal cerebrospinal fluid (CSF) leak and encephalocele repair.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary academic health system.

PATIENTS

Patients undergoing repair of spontaneous temporal lobe encephaloceles or middle fossa CSF leaks during years 2017 to 2023.

INTERVENTIONS

Transmastoid, middle fossa craniotomy, or combination approaches to CSF leak repair.

OUTCOME MEASURES

Failure rate, complication rate, length of stay (LOS), readmission.

RESULTS

Sixty-nine patients were included, with a combination approach performed in 78.3%, transmastoid in 17.4%, and isolated middle fossa craniotomy in 4.3%. Mean body mass index was 33.2, mean bony defect size width was 6.51 mm, and defect locations included the epitympanum, antrum, mastoid, and petrous apex. Multilayer closure with three or more layers was performed in 87.0%. LD was used in 73.9% of cases for a mean duration 2.27 days and was associated with longer LOS (3.27 vs. 1.56 d, p = 0.006) but not with failure rate, complications, discharge destination, or readmission. Only one major complication occurred as a result of the drain, but low-pressure headache was anecdotally common.

CONCLUSIONS

Use of LD in the repair of spontaneous CSF leaks and temporal lobe encephaloceles is associated with longer LOS but not failure rates or other admission-level outcomes.

Use of Soft Cervical Collar Improves Surgeon Ergonomics During Simulated Otologic Surgery

OBJECTIVE

To determine whether surgeon use of a soft cervical collar during endoscopic and microscopic otologic surgery is feasible and impacts surgeon ergonomics as measured by inertial sensors.

STUDY DESIGN

Prospective crossover trial.

SETTING

US-based otolaryngology training program.

PATIENTS

Otolaryngology residents and fellows.

INTERVENTIONS

Therapeutic-use of a soft cervical collar during simulated otologic surgery.

MAIN OUTCOME MEASURES

Time spent in high-risk angles of neck and back flexion and extension; average angle of neck flexion, extension, rotation, and lateral bending; validated assessment of neck pain; average daily phone use.

RESULTS

Fifteen subjects met criteria for inclusion. Ten of 15 (67%) were male. Seven of 15 (47%) were postgraduate year 1-2. Seven of 15 (47%) reported a history of neck pain. None reported prior spinal steroid injections or surgery. Across all subjects, use of the soft cervical collar significantly reduced time spent in high-risk angles of neck flexion/extension during both endoscopic (56% vs. 35%, p < 0.05) and microscopic (60% vs. 32%, p < 0.05) otologic surgery. There was no effect on back flexion or extension. There was no difference in time spent in high-risk neck or back angles between endoscopic and microscopic surgery. Average angles of neck or back flexion, extension, lateral bending, and rotation were not significantly different for subgroups with more operative experience, increased phone use, perception of good posture, or history of neck pain.

CONCLUSIONS

Use of a soft cervical collar during simulated otologic surgery significantly reduced time spent in high-risk neck positions. These data support feasibility of soft collar use during otologic surgery and hold promise for reduction in the high rates of neck pain reported by neurotologists.

PROFESSIONAL PRACTICE GAP AND EDUCATIONAL NEED

Improving surgeon ergonomics for otologic surgery.

LEARNING OBJECTIVE

To identify a therapeutic intervention to mitigate neck pain in surgeons caused by assumption of high-risk cervical neck flexion and extension.

DESIRED RESULT

To demonstrate that use of a readily available soft cervical collar reduces risk of neck pain in otologic surgeons.

LEVEL OF EVIDENCE

II.

INDICATE IRB OR IACUC

Exempt.

A Review of Noninfectious Diseases Masquerading as Acute Mastoiditis

OBJECTIVE

Acute mastoiditis is commonly attributed to infection. Rarely do clinicians encounter cases that do not respond to traditional antibiotics or surgical management. The goal of this study was to systematically review the literature to characterize diseases masquerading as acute infectious mastoiditis.

DATA SOURCES

PubMed, Embase, and Scopus.

REVIEW METHODS

A systematic review was performed to identify all publications that reported on diseases with presentations mimicking acute mastoiditis, defined as postauricular redness, swelling, and tenderness. We included clinical prospective studies, retrospective studies, and case series/reports. Exclusion criteria included non-English articles, letters/commentaries, abstracts, and review articles.

RESULTS

Out of 3339 results, 35 studies met final inclusion criteria. In children, 11 diseases were reported to mimic mastoiditis, including solid tumors, hematologic diseases, and autoimmune/inflammatory diseases. The most common disease in children was Langerhans cell histiocytosis, followed by rhabdomyosarcoma and acute myelogenous leukemia. In adults, 8 additional diseases were reported. The most common disease in adults was squamous cell carcinoma, followed by nasopharyngeal carcinoma and Langerhans cell histiocytosis. Presenting symptoms are reviewed, as well as characteristic radiographic, laboratory, and intraoperative features that may assist with diagnosis. A diagnostic algorithm for atypical cases of acute mastoiditis is proposed.

CONCLUSION

A small but significant group of diseases in children and adults can mimic acute mastoiditis. In such cases, history and examination alone may be insufficient to reach a diagnosis, and further investigation may be necessary. Otolaryngologists should always be mindful of the possibility that noninfectious pathologies may present with a constellation of symptoms similar to mastoiditis.

Initial Experience With Two Active Transcutaneous Bone-Anchored Hearing Implants

OBJECTIVE

To analyze our institutional experience with two active transcutaneous bone-anchored hearing aids.

STUDY DESIGN

Retrospective cohort study.

SETTING

Tertiary academic otology-neurotology practice.

PATIENTS

Patients with conductive or mixed hearing losses meeting criteria to receive active transcutaneous bone-anchored hearing aids.

INTERVENTIONS

Implantation with one of two active transcutaneous bone-anchored hearing aids.

OUTCOME MEASURES

Operative time, dural exposure and decompression, use of lifts, implant position, ease of use, qualitative patient satisfaction, complication rates.

RESULTS

Ten patients received Implant 1 and 11 patients received Implant 2. The most common underlying etiologies of hearing loss were chronic suppurative otitis media in 33.3%, atresia/microtia in 23.8%, and cholesteatoma in 23.8%. Average operative times were 99.3 minutes for Implant 1 and 80.9 minutes for Implant 2 ( p = 0.263). Implant 1 required lifts in 60%, dural exposure in 50%, and dural compression in 30%. Overall, placement was difficult in 47.6% of cases. There were no intraoperative complications. There were higher rates of issues with sound quality (27.3% versus 0.0%, p = 0.123) and poor cosmesis (36.4% versus 10.0%, p = 0.360) with Implant 2. Functional gain was not recorded, but all patients derived qualitative benefit from their implant. Three patients had local wound complications that self-resolved or were treated with antibiotics. One patient implanted at an outside institution required explant because of multiple infections.

CONCLUSIONS

There were no statistically significant differences in outcomes comparing Implants 1 and 2; however, Implant 2 had much higher rates of issues with audio quality and poor cosmesis. Placing Implant 1 often required special techniques.

Sharing in-office otoendoscopy recordings may improve patient satisfaction: A prospective cohort study

OBJECTIVE

Evaluate the impact of sharing otoendoscopy exams on patient satisfaction in the outpatient clinical setting.

METHODS

Randomized, prospective cohort study. Consecutive adults presenting to otology clinic at one tertiary referral center were randomized into two groups: standard microscopy (SM) and video otoendoscopy (VO). The SM group had ears examined using a standard, otomicroscope; the VO group had ears examined using a 0° rigid endoscope connected to a video tower. All subjects were counseled on their exam findings in a routine manner; the VO group was concurrently shown a recording of their ear exam. All subjects completed the 18-item Patient Satisfaction Questionnaire (PSQ-18) at the conclusion of their clinic visit.

RESULTS

The SM group consisted of 27 patients and VO group consisted of 23 patients. VO subjects reported higher PSQ-18 scores compared to SM subjects within the domains of communication (p = 0.04) and technical quality (p = 0.005). On linear regression models, demographic factors and positive exam findings were not predictive of patient satisfaction.

CONCLUSIONS

Sharing otoendoscopy recordings may be a valuable tool that can improve patient satisfaction.

PRACTICE IMPLICATIONS

Clinicians should consider sharing recordings of otoscopic exams with patients, particularly when faced with the possibility of surgery.

2-Octyl cyanoacrylate to prevent salivary fistula formation following oral cavity microvascular reconstruction: A prospective trial

BACKGROUND

Salivary fistulas remain a significant problem in patients undergoing major head and neck reconstructive surgery. Surgical sealants have become increasingly used in cutaneous and non-cutaneous wound closure, providing a barrier to fluids/gases and promoting healing. The purpose of this study was to determine the efficacy of a common surgical sealant, 2-Octyl Cyanoacrylate (2-OCA, Dermabond®), in the prevention of salivary fistulas following free flap reconstruction of the oral cavity.

METHODS

In this non-randomized, single arm prospective trial, patients undergoing free flap reconstruction of gravity-dependent oral cavity defects were recruited. Application of 2-OCA was performed along flap inset suture lines at the time of surgery. Prospectively collected trial data were propensity score matched to a control cohort to compare outcomes. Data collected include demographics, medical co-morbidities, previous treatments, primary tumor site, and subsites reconstructed. The primary outcome measure was rate of salivary fistula formation. Secondary outcomes were time to development of leak and percentage of patients tolerating oral feeding at one month post-operatively.

RESULTS

In the 46 propensity score matched pairs, eight (17.4%) out of 46 patients in the 2-OCA prospective cohort and seven (15.2%) out of 46 patients in the control cohort developed postoperative salivary fistulas within the one-month study interval (p = 1.00). The average time to postoperative leak in the 2-OCA group was 12.5 days versus 7.1 days in the control cohort (p = 0.10). In the 2-OCA group, 30 (65.2%) patients were tolerating regular diet at one month post-operatively compared to 33 (71.7%) in the control cohort (p = 0.65).

CONCLUSION

Salivary fistula rates after application of a 2-OCA surgical sealant were not improved compared to a control cohort in this single institutional trial. There are several surgical sealants available, each with varying elasticity and adhesiveness. Future studies are needed to identify surgical sealants that are able to provide sufficient strength and adhesion to seal closures and combat corrosive saliva, but elastic enough to handle motion related tension during swallowing and post-operative movements in the head and neck.

Temporal Bone Encephaloceles: Utility of Preoperative Imaging

Objective

To determine the diagnostic efficacy and clinical value of preoperative computed tomography (CT) and magnetic resonance imaging (MRI) among patients with suspected temporal bone encephaloceles (TBE).

Study Design

Retrospective chart review from 2006 to 2018.

Setting

Tertiary referral center.

Subjects and Methods

The subjects underwent surgery for a clinically suspected TBE or cerebrospinal fluid (CSF) leak. Preoperative imaging test characteristics of CT and MRI, including sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were calculated for TBE scans and compared with intraoperative findings.

Results

Fifty-seven subjects with otorrhea, middle ear effusion, hearing loss, and/or meningitis with suspected TBE or CSF leak were identified. All had preoperative CT scans, and 61% (35/57) had preoperative MRI scans. Intraoperatively, 37 of 57 patients (65%) were found to have a TBE. CT scans (17% sensitivity, 100% specificity, 100% PPV, 46% NPV) were less sensitive than MRI (58% sensitivity, 100% specificity, 100% PPV, 24% NPV) for detecting TBEs. Furthermore, the time from initial scan to operative repair was significantly longer in those who had a CT followed by MRI scan compared with CT alone or a fused CT-MRI scan (mean = 68 vs 15 days, respectively; P = .004).

Conclusion

CT and MRI provide complementary information that may aid surgical planning. However, imaging cannot always rule out TBE. In cases with high clinical suspicion, surgical confirmation is often required for definitive diagnosis and treatment. The cost of an additional preoperative study should be considered before its use.

Fluorescent Detection of Merlin-deficient Schwann Cells and Primary Human Vestibular Schwannoma Cells Using Sodium Fluorescein

HYPOTHESIS

Merlin-deficient Schwann cells (MD-SC) and primary human vestibular schwannoma (VS) cells exhibit selective uptake of sodium-fluorescein (SF), allowing for fluorescent detection and improved visualization of tumor cells, when compared with Schwann cells (SC).

BACKGROUND

SF is a fluorescent compound used for fluorescence-guided resection of gliomas. The utility of SF for VS surgery has not been assessed.

METHODS

Mouse MD-SCs and rat SCs were cultured on 96-well plates at different cell densities and treated with SF at several drug concentrations and durations. Relative fluorescence units (RFU) were measured using a fluorometer to determine optimal treatment parameters in vitro. Subsequently, a four-point Likert scale for fluorescence visualization of pelleted cells was created and validated. Blinded observers rated SF-treated primary human VS and SC cultures, which were developed from deidentified specimens obtained from live and cadaveric donors, respectively.

RESULTS

In contrast to SCs that showed low levels of fluorescence, MD-SCs demonstrated dose-dependent increases in RFUs when treated with incremental dosages of SF as well as longer treatment and fluorescent excitation times. In addition, RFUs were higher at greater MD-SC densities. The Likert scale for fluorescence visualization was validated using nine blinded observers and there were excellent inter- and intrarater reliabilities (intraclass coefficients of 0.989 and >0.858, respectively). Using the Likert scale, human VS treated with SF received higher scores than human SCs (p < 0.001).

CONCLUSION

Mouse MD-SC and human VS cells demonstrate preferential uptake of SF when compared with normal primary SCs. Observers detected differences in fluorescence using the validated Likert scale. Further investigations into the utility of SF-guidance in VS surgery are warranted.

Analysis of 855 upper extremity fistulas created using a standard protocol: the role of graft extension to achieve functional status

The Fistula First Breakthrough Initiative (FFBI) has been one of the most important national programs to help achieve considerable improvements in the care of patients on chronic hemodialysis. FFBI has helped place guidelines to push practitioners to reduce the use of tunneled central venous catheters and to increase the rate of arteriovenous fistula use in patients requiring chronic hemodialysis access. However, despite current guidelines, no specific protocols exist for the creation and management of autogenous arteriovenous fistulas and outcomes at most centers are below national benchmarks. In this study, we examine the effectiveness of a standard protocol used at our institution for the creation of autogenous upper extremity fistulas for hemodialysis access in achieving early cannulation and early removal of tunneled dialysis catheters. Our review encompasses 855 consecutive autogenous fistulas created over a 10-year period. Our findings suggest that the use of a standard protocol for creation and management of autogenous fistulas can help increase the rate of functional accesses over national benchmarks. Additionally, extension/conversion of malfunctioning fistulas to grafts appears to be an excellent method to expedite removal of a tunneled dialysis catheter with concomitant preservation of a fistula.

Alterations in blood-brain barrier permeability to large and small molecules and leukocyte accumulation after traumatic brain injury: effects of post-traumatic hypothermia

We investigated the temporal and regional profile of blood-brain barrier (BBB) permeability to both large and small molecules after moderate fluid percussion (FP) brain injury in rats and determined the effects of post-traumatic modest hypothermia (33 degrees C/4 h) on these vascular perturbations. The visible tracers biotin-dextrin-amine 3000 (BDA-3K, 3 kDa) and horseradish peroxidase (HRP, 44 kDa) were injected intravenously at 4 h or 3 or 7 days post-TBI. At 30 min after the tracer infusion, both small and large molecular weight tracers were detected in the contusion area as well as remote regions adjacent to the injury epicenter in both cortical and hippocampal structures. In areas adjacent to the contusion site, increased permeability to the small molecular weight tracer (BDA-3K) was evident at 4 h post-TBI and remained visible after 7 days survival. In contrast, the larger tracer molecule (HRP) appeared in these remote areas at acute permeable sites but was not detected at later post-traumatic time periods. A regionally specific relationship was documented at 3 days between the late-occurring permeability changes observed with BDA-3K and the accumulation of CD68-positive macrophages. Mild hypothermia initiated 30 min after TBI reduced permeability to both large and small tracers and the infiltration of CD68-positive cells. These results indicate that moderate brain injury produces temperature-sensitive acute, as well as more long-lasting vascular perturbations associated with secondary injury mechanisms.

Therapeutic hypothermia modulates TNFR1 signaling in the traumatized brain via early transient activation of the JNK pathway and suppression of XIAP cleavage

Tumor necrosis factor (TNF) plays a critical role in pathomechanisms associated with secondary damage after traumatic brain injury (TBI). The TNF ligand-receptor system stimulates inflammation by activation of gene transcription through the IkappaB kinase (IKK)-NF-kappaB and c-Jun NH(2)-terminal kinase (JNK)-AP-1 signaling cascades. TNF signaling following TBI involves both cell survival and apoptotic pathways, but the mechanism that accounts for the dual role of TNF remains unclear. Multiple studies have reported hypothermia to be protective following TBI, but the precise mechanism has not been clearly defined. Here, TNFR1 signaling pathways were investigated in the cerebral cortex of adult male Sprague-Dawley rats subjected to moderate fluid-percussion TBI and of naïve controls. Another group was subjected to moderate TBI with 30 min of pre- and post-traumatic hypothermia (33 degrees C). Rapid and marked increases in protein expression of TNFR1 and signaling intermediates in both the IKK-NF-kappaB and JNK pathways were induced in traumatized cortices. Hypothermia decreased TNFR1 protein expression acutely in traumatized cortices and stimulated early activation of signaling intermediates in the JNK, but not the IKK-NF-kappaB, signaling pathways. Hypothermia promoted a rapid activation of caspase-3 acutely after injury but suppressed caspase-3 activation at later time points. Moreover, hypothermia treatment suppressed cleavage of X-linked inhibitor of apoptosis protein (XIAP) into fragments induced by TBI. These data suggest that hypothermia may regulate both the JNK signaling cascade via XIAP and the preconditioning pathways that activate caspases. Thus, hypothermia mediates TNFR1 responses via early activation of the JNK signaling pathway and caspase-3, leading to endogenous neuroprotective events.

Sign language in childhood epileptic aphasia (Landau-Kleffner syndrome)

Acquired epileptic aphasia (AEA, or Landau-Kleffner syndrome) is a unique condition in which children can lose oral language (OL) comprehension and expression for a prolonged period. These children can benefit from visual forms of language, mainly sign language (SL), but the quality of SL has never been analyzed. The case is reported here of a boy with AEA who lost speech comprehension and expression from 3 years 6 months to 7 years and was educated in SL from the age of 6 years. His SL was evaluated at the age of 13 years and 6 months and compared with a control child with congenital sensorineural deafness. It was found that: (1) our patient achieved the same proficiency in SL as the control child with deafness; (2) SL learning did not compete with, but perhaps even hastened, the recovery of OL. Intact ability to learn a new linguistic code such as SL suggests that higher-order language areas were preserved and received input from a separate visual route, as shown by neuropsychological and functional imaging research in deaf and hearing signers.

Low-grade (fibromatosis-like) spindle cell carcinoma of the breast

Spindle cell carcinoma of the breast, a variant of metaplastic carcinoma, includes a wide spectrum of lesions with histomorphologic and nuclear features ranging from overtly malignant to mildly atypical. Spindle cell carcinomas with mildly atypical features may resemble fasciitis, fibromatosis, or myofibroblastic tumors and therefore are often misinterpreted as such. A recent study has suggested that spindle cell carcinomas with a dominant fibromatosis-like phenotype, unlike spindle cell carcinomas in general, have no propensity for distant metastasis and should be termed "tumors" rather than "carcinomas." To investigate the question of fibromatosis-like spindle cell breast carcinoma (FLSpCCs) metastatic potential, we studied cases of FLSpCC seen at the University of Texas M.D. Anderson Cancer Center between 1987 and 2000. Clinical, pathologic, and immunophenotypic features were reviewed, with emphasis on biologic behavior and predictors of clinical outcome. Our series included 24 women who ranged in age from 55 to 85 years (mean 66 years). Tumor size ranged from 1.0 to 5 cm (mean 2.8 cm). Most tumors were grossly well defined but had microscopic infiltrative borders. Tumors showed a dominant fibromatosis-like or myofibroblastic-like growth pattern with prominent collagenization. Inflammatory infiltrate was noted in the majority of tumors. Cytokeratin-positive cells were seen in all cases and usually appeared as cords or sheets of polygonal cells; isolated cytokeratin-positive cells were rare. In most tumors immunoreactivity for smooth muscle actin (SMA) was confined to the cytokeratin-negative cells. In five cases intense co-expression of cytokeratin and SMA was noted. None of the tumors showed immunoreactivity for smooth muscle heavy chain myosin, estrogen receptors, progesterone receptors, or HER-2/neu. Ki-67 expression was noted in fewer than 5% of tumor cells. Treatment consisted of local excision (seven cases) or modified radical mastectomy (13 cases). Treatment was unknown in four cases. In patients who underwent axillary nodal dissection, no lymph node metastases were found. Two of the six patients who underwent local excision developed local recurrence. Two patients who underwent modified radical mastectomy developed lung metastases within 2 years after the initial diagnosis. The metastatic tumors were histologically similar to the primary tumors. Our findings indicate that FLSpCCs have the potential for local recurrence and distant metastasis and should be treated accordingly. Because FLSpCCs may be underdiagnosed as benign, the use of immunohistochemical studies, especially for cytokeratins and SMA, is essential in the evaluation of any spindle cell proliferations of the breast.

Acquired hippocampal damage after temporal lobe seizures in 2 infants

Two infants developed unilateral hippocampal swelling on magnetic resonance imaging after prolonged seizures of temporal origin. Subsequent images suggested hippocampal sclerosis. The first child had febrile status epilepticus with exanthem subitum and developed refractory complex partial seizures. Histological findings after temporal lobectomy confirmed hippocampal sclerosis but also revealed sequelae of a focal encephalitis and microdysgenesis of the hippocampus. The second child had signs of brain dysgenesis, but acquired hippocampal damage affecting each side successively was documented by serial magnetic resonance imaging. These cases illustrate that different clinical conditions combining preexisting and acquired pathological characteristics can lead to hippocampal sclerosis.