Wong Wai Lun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 119-125). / Abstract also in Chinese. / Acknowledgments --- p.i / Legend for Figures --- p.ii / Legend for Tables --- p.iv / Abstract --- p.v / Abstract in Chinese --- p.ix / Chapter Chapter I --- Introduction --- p.1 / Objective --- p.5 / Chapter Chapter II --- Literature Review / Chapter II.1. --- Anatomy of the urinary system --- p.6 / Chapter II.2. --- Physiology of the urinary system --- p.10 / Chapter II.3. --- Methods for investigating the urinary system --- p.12 / Chapter II.3.1. --- Plain film radiography --- p.12 / Chapter II.3.2. --- Excretory Urogram --- p.12 / Chapter II.3.3. --- Ultrasound --- p.13 / Chapter II.3.4. --- Computed Tomography --- p.15 / Chapter II.3.5. --- Renal Angiography --- p.16 / Chapter II.3.6. --- Magnetic Resonance Imaging (MRI) --- p.16 / Chapter II.3.7. --- Radionuclide Imaging --- p.17 / Chapter II.4. --- Radiopharmaceuticals for renal parenchyma imaging --- p.17 / Chapter II.4.1. --- Tc-99m GHA --- p.18 / Chapter II.4.1.1. --- Chemistry of Tc-99m GHA --- p.18 / Chapter II.4.1.2. --- Preparation --- p.18 / Chapter II.4.1.3. --- Doses --- p.18 / Chapter II.4.1.4. --- Biological behavior --- p.19 / Chapter II.4.2. --- Tc-99m DMSA / Chapter II.4.2.1. --- Chemistry of Technetium-99m Dimercaptosuccinic Acid (Tc-99m DMSA) --- p.20 / Chapter II.4.2.2. --- Chemical property of Tc-99m DMSA --- p.21 / Chapter II.4.2.3. --- Preparation --- p.22 / Chapter II.4.2.4. --- Radiochemical purity measurement --- p.22 / Chapter II.4.2.5. --- Doses --- p.23 / Chapter II.4.2.6. --- Pharmacokinetic of Tc-99m DMSA --- p.23 / Chapter II.4.2.7. --- Renal handling of injected Tc-99m DMSA --- p.25 / Chapter II.5. --- General consideration for quantitative uptake measurement in organs --- p.26 / Chapter II.5.1. --- Clinical significance of renal Tc-99m DMSA uptake --- p.28 / Chapter II.5.2. --- Special consideration and problems for quantitative renal Tc-99m uptake measurement --- p.29 / Chapter II.5.3. --- Suggestions and solutions for quantitative renal Tc-99m uptake measurement --- p.29 / Chapter II.5.3.1. --- Planar images Vs SPECT images for quantification --- p.29 / Chapter II.5.3.2. --- Background subtraction --- p.31 / Chapter II.5.3.3. --- Choice of location for background ROI --- p.32 / Chapter II.5.3.4. --- Attenuation --- p.35 / Chapter II.5.3.5. --- Principle of the conjugate view method --- p.36 / Chapter II.5.3.6. --- Body thickness and kidney depth measurement --- p.37 / Chapter II.6. --- Glomerular Filtration / Chapter II.6.1. --- Introduction --- p.39 / Chapter II.6.2. --- Gold standard for GFR measurement --- p.40 / Chapter II.6.3. --- Laboratory studies for the measurement of glomerular filtration : Serum Creatinine and Blood Urea Nitrogen (BUN) levels --- p.41 / Chapter II.6.3.1. --- Calculation of Creatinine Clearance Rate --- p.43 / Chapter II.6.3.2. --- Critique for using creatinine clearance as a measurement of renal function --- p.44 / Chapter II.6.3.3. --- Limitation of the serum creatinine concentration used alone as a measurement of renal function --- p.46 / Chapter II.6.4. --- Radionuclide technique for the assessment of the glomerular function --- p.48 / Chapter II.6.4.1. --- Diethylene Triamine Penta Acetic acid (DTPA) --- p.49 / Chapter II.6.4.2. --- Methods / Chapter II.6.4.2.1. --- Measurement of Glomerular Filtration Rate using Tc-99m DTPA with single injection techniques --- p.51 / Chapter II.6.4.2.2. --- Compartment model --- p.52 / Chapter II.6.4.2.2a. --- Two-compartment model --- p.52 / Chapter II.6.4.2.2b. --- Single-compartment model --- p.54 / Chapter II.6.4.2.3. --- Single blood sample technique: a modification of Tauxe's OIH method in which counts in a single plasma sample correlated with a GFR nomogram --- p.56 / Chapter II.6.4.2.4. --- Gamma camera based method --- p.58 / Chapter II.6.4.2.4a. --- Gates-modification of Schlegel's OIH technique --- p.58 / Chapter II.6.4.2.4b. --- Critique for the Gamma camera technique for measuring GFR --- p.62 / Chapter II.7. --- The relationship between the Tc-99m DMSA uptake and GFR --- p.67 / Chapter Chapter III --- Material and Methods --- p.69 / Chapter III.1. --- Subjects and Sampling Methods --- p.69 / Chapter III.2. --- Quantitation of Absolute DMSA uptake --- p.70 / Chapter III.2.1. --- Parameters for Tc-99m DMSA uptake study --- p.70 / Chapter III.2.1.1. --- Materials and methods --- p.70 / Chapter III.2.1.1.1. --- Instrumentation --- p.70 / Chapter III.2.1.1.2. --- Dosage --- p.70 / Chapter III.2.1.1.3. --- Optimum acquisition start time --- p.70 / Chapter III.2.1.1.4. --- Length of acquisition time --- p.71 / Chapter III.2.1.1.5. --- Acquisition parameter --- p.71 / Chapter III.3. --- Calculation of absolute renal DMSA uptake --- p.72 / Chapter III.3.1. --- Attenuation Coefficient factor(μ) --- p.73 / Chapter III.3.2. --- Table attenuation --- p.75 / Chapter III.3.3. --- Body thickness measurement --- p.77 / Chapter III.3.4. --- Decay correction --- p.78 / Chapter III.3.5. --- Calculation of DMSA uptake --- p.78 / Chapter III.3.6. --- Counting dose injected --- p.80 / Chapter III.3.7. --- Calculation of absolute quantitation of Tc-99m DMSA uptake --- p.80 / Chapter III.3.8. --- Dose infiltration --- p.81 / Chapter III.4. --- GFR measurement --- p.82 / Chapter III.4.1. --- Instrumentation --- p.82 / Chapter III.4.2. --- Methods --- p.82 / Chapter III.5. --- Statistical and analytical methods --- p.84 / Chapter Chapter IV --- Results --- p.87 / Chapter IV. 1. --- Characteristics of experimental subjects and their serum creatinine profile --- p.88 / Chapter IV.2. --- Absolute Tc-99m DMSA uptake / Chapter IV.2.1. --- The change of absolute Tc-99m uptake with time --- p.89 / Chapter IV.2.2. --- Absolute Tc-99m DMSA uptake measurement at 6 and 24 hours --- p.90 / Chapter IV.2.3. --- Gender difference in absolute Tc-99m uptake measurement at 6 hour --- p.92 / Chapter IV.3. --- GFR measurement --- p.93 / Chapter IV.3.1. --- GFR measurement by single (3hr) and double (1&3 hrs) plasma sampling --- p.93 / Chapter IV.3.2. --- Gender difference in GFR measurement using single plasma sampling --- p.96 / Chapter IV.4. --- Univariate Correlation --- p.97 / Chapter IV.4.1. --- Correlation between GFR using single plasma sampling and absolute Tc-99m uptake --- p.97 / Chapter IV.4.2. --- Correlation between GFR using single plasma sampling and plasma creatinine levels --- p.98 / Chapter IV.4.3. --- Correlation between anthropometric variables on GFR(3 hr) --- p.99 / Chapter IV.4.4. --- Correlation between anthropometric variables and serum creatinine plasma level on absolute Tc-99m DMSA uptake measurement at 6 hour --- p.101 / Chapter IV.4.5. --- Multiple linear stepwise regression --- p.103 / Chapter Chapter V. --- Discussion / Chapter V. 1 --- . Review of the study --- p.104 / Chapter V.1.1. --- Experimental subjects and their absolute Tc-99m DMSA uptake (%) at 6 hr --- p.104 / Chapter V.1.2. --- Experimental subjects and their GFR(3 hr) --- p.105 / Chapter V.2. --- Discussion on subject --- p.105 / Chapter V.2.1. --- Subject preparation --- p.106 / Chapter V.3. --- Discussion of method --- p.106 / Chapter V.3.1. --- Equipment --- p.106 / Chapter (a) --- Dose calibrator --- p.106 / Chapter (b) --- The sensitivity of the head 1 and 2 of the gamma camera --- p.106 / Chapter (c) --- Validation of quantification of injected activity by gamma camera method--------constancy of performance for gamma camera --- p.110 / Chapter (d) --- LEHR Collimator --- p.112 / Chapter (f) --- Dead time loss --- p.112 / Chapter V.4. --- Discussion on measurement --- p.113 / Chapter (a) --- Length of acquisition time --- p.113 / Chapter (b) --- Attenuation Coefficient factor (\x) --- p.113 / Chapter (c) --- "Body thickness, L, measurement" --- p.113 / Chapter (d) --- Optimum acquisition time for data collection --- p.115 / Chapter v.5. --- Discussion on overall error estimation --- p.115 / Chapter (a) --- Tc-99m DMSA uptake measurement at 6 hr --- p.115 / Chapter (b) --- GFR measurement by single (3 hr) sample --- p.116 / Chapter Chapter VI --- Conclusion --- p.117 / Reference --- p.119 / Appendix I --- p.126 / Appendix II --- p.128 / Appendix III --- p.134

INTRODUÇÃO: O limite de tempo de isquemia renal sem causar um dano permanente à função ainda é um questionamento pertinente na prática cirúrgica urológica. Algumas cirurgias requerem um campo cirúrgico menos sangrante, necessitando de uma interrupção temporária do fluxo sanguíneo para o parênquima renal através de clampeamento do pedículo. Este estudo objetivou avaliar qual técnica de clampeamento em isquemia isotérmica é superior, em termos de preservação da função renal. MÉTODOS: Neste estudo, foram utilizados 28 coelhos da raça New Zealand distribuídos em quatro grupos de forma randomizada e submetidos à laparotomia com interrupção do fluxo sanguíneo renal esquerdo, conforme grupo: grupo 1 - Controle, sem isquemia (4 animais), grupo 2 - Isquemia seletiva (8 animais), grupo 3 - Isquemia não-seletiva (8 animais) e grupo 4 - Isquemia não-seletiva intermitente (8 animais). Os animais foram submetidos à análises cintilográficas da função renal com mercaptoacetiltriglicina (MAG3) e dosagens séricas de creatinina no pré-operatório, no primeiro, terceiro e sétimo dias pós-operatórios. Após 15 dias da cirurgia, os animais foram sacrificados e os rins submetidos à análise histológica. RESULTADOS: A análise cintilográfica da função renal mostrou que os três grupos submetidos à isquemia apresentaram um agravo semelhante, nas primeiras 24 horas; não havendo diferença estatística entre eles no tocante a perda de função renal do rim esquerdo (p= 0,165), neste período. No exame do terceiro dia pós-operatório, houve diferença estatística (p= 0,006) entre os grupos não-seletivo (3) e o intermitente (4), mostrando uma superioridade do fator desclampeamento na proteção à função renal. No sétimo dia pós-operatório, o grupo do clampeamento seletivo (2) mostrou-se superior (p< 0,001) ao grupo não-seletivo (3), mas não apresentou diferença estatística em relação ao grupo intermitente (4). Este último, por sua vez, também apresentou-se superior ao grupo 3, com diferença estatística (p< 0,001). Após sete dias não foi observada diferença estatística entre os grupos 2 e 4. A histologia e a creatinina não mostraram diferença estatisticamente significante entre os grupos isquêmicos. Do ponto de vista funcional, a isquemia seletiva e a intermitente foram superiores em relação a não-seletiva. CONCLUSÃO: O modelo utilizado neste estudo mostrou uma superioridade da isquemia isotérmica seletiva e da intermitente em relação a não-seletiva na proteção da função renal. Não houve diferença entre o clampeamento seletivo e o intermitente não-seletivo na função do rim / INTRODUCTION: The time limit of renal ischemia with no permanent damage to renal function still remains as a pertinent question in urologic surgical practice. Several procedures require a bloodless surgical field most of time needing an interruption of blood flow to the renal parenchyma and they can require hilum control and clamping. This study assessed which normothermic clamping technique is superior in order to preserve kidney function. METHODS: In this project, 28 New Zealand rabbits were distributed in four groups by randomization and submitted to laparotomy and blood flow interruption of left kidney: Group 1 - Control, no ischemia (four animals), Group 2 Selective ischemia (eight animals), Group 3 Nonselective ischemia (eight animals) e Group 4 intermittent nonselective ischemia (eight animals). The animals were submitted to renal scintigraphy with mercaptoacetiltriglicin (MAG3) and serum creatinine analysis preoperatively and at days 1, 3 and 7 after left hilum clamping. The animals were submitted to nephrectomy and immediately sacrificed and the kidneys subjected to blinded evaluation by a nephropathologist. RESULTS: Renal scintigraphy showed equal damage in the three groups in first 24 hours, with no statistical difference in loss of left kidney function (p= 0,165) in this period. At third day examination, there was statistical difference (p= 0,006) between the nonselective group (3) and intermittent one (4), demonstrating a superiority of declamping factor in renal function protection. At seventh postoperative day, selective group (2) proved to be better (p< 0,001) than nonselective one (3), however there was not statistical difference between group 2 and the intermittent group (4). The intermittent clamping group was also superior to group 3 (p< 0,001). Histopathology and serum creatinine did not demonstrate statistical difference among groups. Functionally, selective and intermittent warm ischemia techniques are better than nonselective one. CONCLUSION: The model used in this study presented a superiority of selective clamping and intermittent arteriovenous clamping in shielding the renal function. No difference occurred between selective clamping and intermittent nonselective one

INTRODUÇÃO: O limite de tempo de isquemia renal sem causar um dano permanente à função ainda é um questionamento pertinente na prática cirúrgica urológica. Algumas cirurgias requerem um campo cirúrgico menos sangrante, necessitando de uma interrupção temporária do fluxo sanguíneo para o parênquima renal através de clampeamento do pedículo. Este estudo objetivou avaliar qual técnica de clampeamento em isquemia isotérmica é superior, em termos de preservação da função renal. MÉTODOS: Neste estudo, foram utilizados 28 coelhos da raça New Zealand distribuídos em quatro grupos de forma randomizada e submetidos à laparotomia com interrupção do fluxo sanguíneo renal esquerdo, conforme grupo: grupo 1 - Controle, sem isquemia (4 animais), grupo 2 - Isquemia seletiva (8 animais), grupo 3 - Isquemia não-seletiva (8 animais) e grupo 4 - Isquemia não-seletiva intermitente (8 animais). Os animais foram submetidos à análises cintilográficas da função renal com mercaptoacetiltriglicina (MAG3) e dosagens séricas de creatinina no pré-operatório, no primeiro, terceiro e sétimo dias pós-operatórios. Após 15 dias da cirurgia, os animais foram sacrificados e os rins submetidos à análise histológica. RESULTADOS: A análise cintilográfica da função renal mostrou que os três grupos submetidos à isquemia apresentaram um agravo semelhante, nas primeiras 24 horas; não havendo diferença estatística entre eles no tocante a perda de função renal do rim esquerdo (p= 0,165), neste período. No exame do terceiro dia pós-operatório, houve diferença estatística (p= 0,006) entre os grupos não-seletivo (3) e o intermitente (4), mostrando uma superioridade do fator desclampeamento na proteção à função renal. No sétimo dia pós-operatório, o grupo do clampeamento seletivo (2) mostrou-se superior (p< 0,001) ao grupo não-seletivo (3), mas não apresentou diferença estatística em relação ao grupo intermitente (4). Este último, por sua vez, também apresentou-se superior ao grupo 3, com diferença estatística (p< 0,001). Após sete dias não foi observada diferença estatística entre os grupos 2 e 4. A histologia e a creatinina não mostraram diferença estatisticamente significante entre os grupos isquêmicos. Do ponto de vista funcional, a isquemia seletiva e a intermitente foram superiores em relação a não-seletiva. CONCLUSÃO: O modelo utilizado neste estudo mostrou uma superioridade da isquemia isotérmica seletiva e da intermitente em relação a não-seletiva na proteção da função renal. Não houve diferença entre o clampeamento seletivo e o intermitente não-seletivo na função do rim / INTRODUCTION: The time limit of renal ischemia with no permanent damage to renal function still remains as a pertinent question in urologic surgical practice. Several procedures require a bloodless surgical field most of time needing an interruption of blood flow to the renal parenchyma and they can require hilum control and clamping. This study assessed which normothermic clamping technique is superior in order to preserve kidney function. METHODS: In this project, 28 New Zealand rabbits were distributed in four groups by randomization and submitted to laparotomy and blood flow interruption of left kidney: Group 1 - Control, no ischemia (four animals), Group 2 Selective ischemia (eight animals), Group 3 Nonselective ischemia (eight animals) e Group 4 intermittent nonselective ischemia (eight animals). The animals were submitted to renal scintigraphy with mercaptoacetiltriglicin (MAG3) and serum creatinine analysis preoperatively and at days 1, 3 and 7 after left hilum clamping. The animals were submitted to nephrectomy and immediately sacrificed and the kidneys subjected to blinded evaluation by a nephropathologist. RESULTS: Renal scintigraphy showed equal damage in the three groups in first 24 hours, with no statistical difference in loss of left kidney function (p= 0,165) in this period. At third day examination, there was statistical difference (p= 0,006) between the nonselective group (3) and intermittent one (4), demonstrating a superiority of declamping factor in renal function protection. At seventh postoperative day, selective group (2) proved to be better (p< 0,001) than nonselective one (3), however there was not statistical difference between group 2 and the intermittent group (4). The intermittent clamping group was also superior to group 3 (p< 0,001). Histopathology and serum creatinine did not demonstrate statistical difference among groups. Functionally, selective and intermittent warm ischemia techniques are better than nonselective one. CONCLUSION: The model used in this study presented a superiority of selective clamping and intermittent arteriovenous clamping in shielding the renal function. No difference occurred between selective clamping and intermittent nonselective one