Opening and closing function of the anal canal assessed by Acoustic Reflectometry

261 Pages·2016·5.55 MB·English

by  James Edward Nicholson

Opening and closing function of the anal canal assessed by Acoustic
Reflectometry
A thesis submitted to the University of Manchester for the degree of Doctor of
Medicine in the Faculty of Medical and Human Sciences
2015

James Edward Nicholson
School of Medicine
Contents

LIST OF TABLES ..................................................................................................... 5
LIST OF FIGURES ................................................................................................... 6
ABBREVIATIONS .................................................................................................... 8
ABSTRACT .............................................................................................................. 11
DECLARATION ...................................................................................................... 12
COPYRIGHT STATEMENT ................................................................................. 13
DEDICATION .......................................................................................................... 14
ACKNOWLEDGEMENTS ..................................................................................... 15
PUBLICATIONS AND PRESENTATIONS ......................................................... 16
PUBLISHED PAPERS ................................................................................................. 16
ABSTRACTS ............................................................................................................. 16
ORAL PRESENTATIONS ............................................................................................ 17

SECTION 1 LITERATURE REVIEW .................................................................. 18

INTRODUCTION........................................................................................................ 18
CHAPTER 1 ANATOMY & PHYSIOLOGY ................................................................... 18
Anatomy.............................................................................................................. 18
Physiology .......................................................................................................... 37
CHAPTER 2 FAECAL INCONTINENCE ........................................................................ 49
CHAPTER 3 ANORECTAL INVESTIGATIONS .............................................................. 59
Investigations ..................................................................................................... 59
CHAPTER 4 ACOUSTIC REFLECTOMETRY ................................................................ 81
What is Acoustic Reflectometry? ........................................................................ 81
History of Acoustic Reflectometry ...................................................................... 81
How Reflectometry works .................................................................................. 82
Urethral Pressure Reflectometry (UPR) ............................................................ 83
Anal Acoustic Reflectometry (AAR) ................................................................... 90

SECTION 2 MATERIALS AND METHODS .................................................... 101

CHAPTER 5 METHODS ........................................................................................... 101
Method of performing AAR .............................................................................. 101
Method of performing Manometry ................................................................... 105
Method of performing Electromyography (EMG) ........................................... 108
Method of Performing a Pudendal Nerve Block .............................................. 111
Method of performing Posterior Tibial Nerve Stimulation .............................. 115
Process ............................................................................................................. 117
Ethical approval ............................................................................................... 118

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SECTION 3 RESULTS ......................................................................................... 119

CHAPTER 6 AAR AS A SURROGATE MARKER FOR ANAL CANAL LENGTH ............... 119
Introduction ...................................................................................................... 119
Methods ............................................................................................................ 119
Results .............................................................................................................. 120
Discussion ........................................................................................................ 123
Conclusion ....................................................................................................... 125

CHAPTER 7 AAR AND MANOMETRY THE ORDER OF DATA COLLECTION ............... 126
Introduction ...................................................................................................... 126
Methods ............................................................................................................ 127
Results .............................................................................................................. 129
Discussion ........................................................................................................ 137
Conclusion ....................................................................................................... 141

CHAPTER 8 FILLING RATES OF THE ANAL CANAL ON AAR PARAMETERS ............... 142
Introduction ...................................................................................................... 142
Method.............................................................................................................. 145
Results .............................................................................................................. 147
Discussion ........................................................................................................ 157
Conclusion ....................................................................................................... 162

CHAPTER 9 INVESTIGATION OF THE IAS WITH AAR USING NERVE BLOCKS .......... 163
Introduction ...................................................................................................... 163
Methods ............................................................................................................ 166
Results .............................................................................................................. 169
Discussion ........................................................................................................ 180
Conclusion ....................................................................................................... 184

CHAPTER 10 CAN AAR PREDICT THE RESPONSE TO POSTERIOR TIBIAL NERVE
STIMULATION? ...................................................................................................... 185
Introduction ...................................................................................................... 185
Methods ............................................................................................................ 190
Results .............................................................................................................. 194
Discussion ........................................................................................................ 205
Conclusion ....................................................................................................... 212

SECTION 4 CONCLUSIONS .............................................................................. 213

CHAPTER 11 OVERARCHING CONCLUSIONS .......................................................... 213
AAR and anal canal length .............................................................................. 214
AAR and Manometry the order of data collection ........................................... 215
Filling rates of the anal canal and AAR........................................................... 215
Investigation of the IAS with AAR using regional nerve blocks ...................... 216
Can AAR predict the response to Posterior tibial nerve stimulation? ............. 216

APPENDIX A ......................................................................................................... 218
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REC APPROVAL LETTERS ...................................................................................... 218
APPENDIX B ......................................................................................................... 225
EXAMPLE OF INVITATION LETTER ......................................................................... 225
EXAMPLE OF PATIENT INFORMATION SHEET ......................................................... 226
EXAMPLE OF CONSENT FORM ................................................................................ 229
EXAMPLE OF VAIZEY FI SEVERITY SCORE ............................................................. 230
EXAMPLE OF DATA COLLECTION PROFORMA ......................................................... 231
APPENDIX C ......................................................................................................... 233
CHAPTER 13 ADDITIONAL ANALYSIS .................................................................... 233
APPENDIX D ......................................................................................................... 235
CHAPTER 14 ADDITIONAL ANALYSIS .................................................................... 235
Agreement between subjective and objective success of PTNS ....................... 236
Predictive factors for the success of posterior tibial nerve stimulation .......... 237
REFERENCES ....................................................................................................... 244

Word Count 55131 (including footnotes and endnotes)

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List of Tables

Table 1 Causes of Faecal Incontinence ...................................................................... 52
Table 2 Scoring Systems used in Faecal Incontinence .............................................. 55
Table 3 Vaizey Severity Score ................................................................................... 57
Table 4 Evidence-based summary for tests in faecal incontinence............................ 80
Table 5 Surrogate anal canal length descriptive statistics ........................................ 121
Table 6 Sex, continence and mean AVFS ................................................................ 121
Table 7 Effect of sex and continence on AVFS ....................................................... 122
Table 8 Order Study Demographics ......................................................................... 130
Table 9 Effect of order on AAR and Manometry variables. .................................... 132
Table 10 Demographics for the rate of filling study ................................................ 148
Table 11 Comparison of the rate of AAR on manometry and AAR variables. ....... 150
Table 12 Rate of AAR and passive incontinence..................................................... 156
Table 13 Rate of AAR and urge incontinence. ........................................................ 157
Table 14 Demographics for the study of AAR before and after bPNB ................... 170
Table 15 Reduction in EMG activity post bPNB ..................................................... 172
Table 16 bPNB by route ........................................................................................... 173
Table 17 AAR and manometry variables pre & post bPNB .................................... 174
Table 18 AAR and manometry variables pre & post successful bPNB. .................. 175
Table 19 EMG activity compared to AAR and manometry variables ..................... 176
Table 20 Correlation of AAR and Manometry variables with EMG activity .......... 177
Table 21 PTNS & AAR study demographics .......................................................... 195
Table 22 AAR & HRAM variables before and after PTNS .................................... 196
Table 23 2 week bowel diary before and after PTNS .............................................. 197
Table 24 Questionnaires before and after PTNS ..................................................... 198
Table 25 Summary of the subjective and objective success of PTNS ..................... 199
Table 26 AAR and HRAM variables with objective success 50 for PTNS. ............ 201
Table 27 AAR and HRAM variables with objective success 70 for PTNS ............. 202
Table 28 AAR and HRAM variables with objective success for PTNS .................. 203
Table 29 Success of PTNS and the subgroups of urge and passive FI .................... 204
Table 30 AAR and HRAM variables with subjective success for PTNS ................ 235
Table 31 Subjective and objective agreement at the 50% threshold. ....................... 236
Table 32 Subjective and objective agreement at the 70% threshold. ....................... 237
Table 33 Pre PTNS questionnaire data and objective measures of success. ............ 239
Table 34 Pre PTNS bowel diary variables and objective success ............................ 240
Table 35 Success of PTNS with type of incontinence and previous surgery .......... 241

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List of Figures

Figure 1 Pelvic view of the levator ani. ..................................................................... 20
Figure 2 Puborectalis Muscle. .................................................................................... 21
Figure 3 Lateral view of Denonvilliers Fascia ........................................................... 23
Figure 4 Diagram of the Anal Canal .......................................................................... 25
Figure 5 The Internal and External anal sphincter. .................................................... 26
Figure 6 Historical views of the composition of the external anal sphincter. ............ 29
Figure 7 3 part structure to the external anal sphincter. ............................................. 30
Figure 8 Nerve supply to the anorectum .................................................................... 35
Figure 9 Algorithm for the investigation of Faecal Incontinence .............................. 60
Figure 10 Endoanal Ultrasound Probe ....................................................................... 61
Figure 11 Normal EAUSS orientation and anatomy ................................................. 62
Figure 12 EAUSS Schematic representation ............................................................. 63
Figure 13 3D EAUSS cube ........................................................................................ 64
Figure 14 2D High Resolution Anorectal manometry versus Manometry ................ 72
Figure 15 3D High definition anorectal manometry versus manometry.................... 73
Figure 16 Concentric EMG needle ............................................................................ 77
Figure 17 Electromyography trace ............................................................................. 78
Figure 18 AAR Polyurethane catheter ....................................................................... 86
Figure 19 Cross-sectional area vs. distance into the urethra ...................................... 87
Figure 20 UPR Opening and Closing graph .............................................................. 88
Figure 21 AAR Opening and Closing graph .............................................................. 91
Figure 22 AAR equipment ....................................................................................... 102
Figure 23 Schematic representation of AAR setup .................................................. 102
Figure 24 Manometry catheter ................................................................................. 106
Figure 25 Electromyography system. ...................................................................... 109
Figure 26 Pudendal nerve block needle ................................................................... 112
Figure 27 Landmarks for a transgluteal pudendal nerve block ................................ 114
Figure 28 PTNS needle placement ........................................................................... 116
Figure 29 Surrogate marker of anal canal length graph. .......................................... 120
Figure 30 Overview of Process - Order of data collection....................................... 128
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Figure 31 Agreement for AAR variable Opening pressure depending on order. .... 133
Figure 32 Agreement for AAR variable Opening elastance depending on order .... 133
Figure 33 Agreement for AAR variable Closing pressure depending on order ....... 134
Figure 34 Agreement for AAR variable Closing elastance depending on order ..... 134
Figure 35 Agreement for AAR variable hysteresis depending on order .................. 135
Figure 36 Agreement for AAR variable SOP depending on order .......................... 135
Figure 37 Agreement for AAR variable SOE depending on order .......................... 136
Figure 38 Agreement for manometry variable MRP depending on order ............... 136
Figure 39 Agreement for manometry variable MSP depending on order ................ 137
Figure 40 Overview of Process – Rate of filling...................................................... 146
Figure 41 Agreement for AAR variable opening pressure depending on rate. ........ 151
Figure 42 Agreement for AAR variable opening elastance depending on rate ....... 151
Figure 43 Agreement for AAR variable closing pressure depending on rate .......... 152
Figure 44 Agreement for AAR variable closing elastance depending on rate ......... 152
Figure 45 Agreement for AAR variable hysteresis depending on rate .................... 153
Figure 46 Agreement for AAR variable SOP depending on rate............................. 153
Figure 47 Agreement for AAR variable SOE depending on rate ............................ 154
Figure 48 Agreement for manometry variable MRP depending on AAR rate ........ 154
Figure 49 Agreement for manometry variable MSP depending on AAR rate. ........ 155
Figure 50 Overview of Process – AAR and bPNB ................................................. 168
Figure 51 AAR and manometry variables against EMG activity after bPNB ......... 178
Figure 52 Reduction in Op against the reduction in EMG activity.......................... 179
Figure 53 Overview of Process – AAR and PTNS .................................................. 193
Figure 54 Reduction in SOP against the reduction in MSP ..................................... 233
Figure 55 Reduction in SOP against the reduction in ISP ....................................... 234

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Abbreviations

AAR Anal acoustic reflectometry
AGA American gastroenterology association
ANS Autonomic nervous system
AR Acoustic reflectometry
ARA Anorectal angle
ARM Anorectal physiology measurement
AVFS Anal verge to function sphincter
BET Balloon expulsion Test
bPNB Bilateral pudendal nerve block
Ce Closing elastance
CLM Conjoined longitudinal muscle
CNS Central nervous system
Cp Closing pressure
CSA Cross sectional area
CT Computer tomography
DRE Digital rectal examination
DSP Digital signal processor
DVE Digital vaginal examination
DVF Denonvilliers fascia
EAS External anal sphincter
EAUSS Endoanal ultrasound scan
EMG Electromyography
FI Faecal incontinence
FIQL Faecal incontinence quality of life score
FISI Faecal incontinence severity index
FRI Fatigue rate index
GA General anaesthetic
GIQLI Gastrointestinal quality of life index
HAD Hospital anxiety and depression Scale
HPZ High pressure zone
HRAM High resolution anorectal manometry
Hy Hysteresis
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IAS Internal anal sphincter
IBS Irritable bowel syndrome
ICC Interstitial cells of Cajal
ICS International continence society
MDT Multidisciplinary team
MEP Motor evoked potential
MHQ Manchester health questionnaire
MRI Magnetic resonance imaging
MRP Maximum resting pressure
MSP Maximum squeeze pressure
MU Motor unit
MUP Motor unit potential
NICE National institute of clinical excellence
NMB Neuromuscular block
ODS Obstructive defecation syndrome
Oe Opening elastance
Op Opening pressure
PCO Patient centred outcomes
PNE Peripheral nerve evaluation
PNTML Pudendal nerve terminal motor latencies
PTNS Posterior tibial nerve stimulation
PSNS Parasympathetic nervous system
QOL Quality of life
RAIR Recto-anal inhibitory reflex
RBL Rubber band ligation
RCT Randomised control trial
REC Regional Ethics Committee
rIGLE’s Rectal intraganglionic laminar endings
SF-36 Medical Outcomes Survey Short-Form
SM Smooth muscle
SNS Sacral nerve stimulation
SOE Squeeze opening elastance
SOP Squeeze opening pressure
SPSS Statistical package for the social sciences
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SyNS Sympathetic nervous system
SqOe Squeeze opening elastance
SqOp Squeeze opening pressure
SUI Stress urinary incontinence
TTNS Transcutaneous tibial nerve stimulation
UI Urinary incontinence
UPR Urethral pressure reflectometry
WPAM Water perfused anal manometry

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